Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Enantioselective reduction of ketones with (EtO)(2)MeSiH catalyzed by an in-situ generated N-heterocyclic carbene (NHC) Ir complex at room temperature has been developed. A series of benzimidazolium salts were synthesized and screened in the asymmetric hydrosilylation reaction. As a result, propiophenone was efficiently reduced by the combined catalytic system of [IrCl(cod)](2) and NHC-Ag complex derived from N-(1-naphthalenylmethyl)-substituted benzimidazolium salt L12, affording the corresponding alcohol in 92% yield and with 92% ee. Moreover, the evaluation of an Ir catalyst precursor showed that cationic [Ir(cod)(2)]BF4 complex could be used. Furthermore, the introduction of a chiral hydroxyamide side arm into the benzimidazolium salt was critical for the successful design of the NHC ligand. (C) 2016 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.molcata.2016.05.020

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

The asymmetric 1,4-addition of Et2Zn to 2-cyclohexen-1-one using a Cu(I) salt/N-heterocyclic carbene (NHC)-Ag complex catalytic system afforded optically active 3-ethylcyclohexanone. The reversal of enantioselectivity using the same catalytic system was achieved by changing the order of the addition of substrates.

DOI： 10.1039/c5ra25926f

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

A hydroxyamide-functionalized azolium salt as the precursor of a (+/-)-trans-1,2-cyclohexanediamine-based bis(NHC) ligand was designed and synthesized from readily accessible l-leucinol. The combination of a Cu salt with this chiral ligand precursor promoted the asymmetric conjugate addition of Et2Zn to 2-cyclohexen-1-one at room temperature without the need for temperature control to afford the corresponding 1,4-adduct with up to 95% ee.

DOI： 10.1055/s-0034-1378916

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

C-2-symmetric ester-amide functionalized azolium salt was synthesized from readily available a-amino ester such as L-serine methyl ester. The combination of a Cu salt and the chiral azolium salt promoted the asymmetric conjugate addition reaction of enones with dialkylzincs. Thus, treatment of acyclic enone such as chalcone with Et2Zn afforded the corresponding 1,4-adduct with up to 85% ee. An excellent ee value of 93% was obtained when 3-nonen-2-one was reacted with Et2Zn. The present catalytic system was found to be useful for the 1,4-addition reaction of cyclic enone. For example, the reaction of 2-cyclohepten-1-one with Et2Zn produced (R)-3-ethylcycloheptanone with 80% ee. (C) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.molcata.2014.08.006

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

A series of functionalized azolium compounds were synthesized from chiral alpha-amino acid derivatives such as beta-amino alcohols. Reaction of hydroxy-amide-functionalized azolium salts thus obtained with Ag2O afforded N-heterocyclic carbene-Ag (NHC-Ag) complexes. Subsequent treatment of the resulting silver compound with [IrCl(cod)](2) yielded monodentate IrCl(cod)(NHC), which was stable in air. The NHC-Ir complex facilitated efficient asymmetric hydrosilylation of ketones using (EtO)(2)MeSiH under ambient conditions. A chiral ligand containing an isobutyl stereodirecting group was found to be the best ligand for the functionalized NHC-Ir complexes that were examined. A linear relationship was found between the catalyst ee and the product ee. The hydroxy functional group on the NHC ligand side-arm not only induced stereocontrol but also enhanced the reaction rate.

DOI： 10.1002/ejoc.201402279

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

A series of new N-heterocyclic carbene (NHC)-Ru(II) complexes functionalized with additional hemilabile donor groups, such as a hydroxy-amide group, were successfully synthesized and structurally characterized. Preliminary studies indicated that the complexes acted as precatalysts with moderate activity in the asymmetric transfer hydrogenation at room temperature without temperature control. The investigation of the effect of varying the eta(6)-arene ligands showed that these ligands appeared to significantly alter the activity of the complexes as precatalysts. Furthermore, it was revealed that the hydroxy functional group on the NHC ligand side-arm not only induced the stereoselectivity of the reaction but also enhanced the reaction rate. (C) 2013 Elsevier B. V. All rights reserved.

DOI： 10.1016/j.jorganchem.2013.04.028

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Language：Japanese   Publisher：The Society of Synthetic Organic Chemistry, Japan  

The Cu-catalyzed 1,4-addition of organometallic reagents to α,β-unsaturated compounds is a powerful method for the efficient construction of carbon-carbon bonds. In the past decade, catalytic asymmetric conjugate addition reactions with high enantioselectivities have been successfully achieved by using a variety of chiral ligands. Among the growing number of the chiral ligands, <i>N</i>-heterocyclic carbenes (NHCs) have been recognized as useful ligands. One of the most attractive features that make NHCs a very interesting class of ligands is the easy access to their ligand precursors (mostly azolium salts). The azolium salts are very easy to functionalize often by simple reactions that allows the design of a wide variety of NHC ligands and the rapid elaboration of NHC ligand libraries. In this review article, the Cu-catalyzed asymmetric conjugate addition reactions by employing easy accessible and highly tunable functionalized azolium salts are summarized.

DOI： 10.5059/yukigoseikyokaishi.71.319

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Other Link： https://jlc.jst.go.jp/DN/JALC/10017543513?from=CiNii

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

The versatility of the anionic tethered NHC ligand system for the Pd-catalyzed allylic asymmetric alkylation (AAA) reaction was investigated. A well defined anionic amidate/NHCePd(II) complex catalyzed the AAA reaction of 1,3-diphenylprop-3-en-1-yl acetate (5) with NaCH(CO2Me)(2). Similarly, the AAA reaction occurred by employing an NHC-Pd(II) complex that was generated in situ. Screening of a wide variety of NHC ligand precursors revealed that the combination of [Pd(allyl)Cl](2) and the azolium salt 9, containing a 3-pentyl group at N(3) position in the NHC ring, efficiently promoted the AAA reaction to afford the corresponding alkylated product 7 with 67% ee. Furthermore, it was found that the Pd/NHC ratio was an important factor; the AAA reaction with a Pd/NHC ratio of 1:1 took place smoothly, whereas utilization of a Pd/NHC ratio of 1:2 resulted in low conversion of the substrates probably by the formation of the catalytically inert bis(NHC)-Pd(II) complex. In fact, an independent experiment showed that the bis(NHC)-Pd(II) complex was formed by treating [Pd(allyl)Cl](2) with two equivalents of NHC-Ag complex. Further investigations on the catalytic AAA reaction revealed significant improvements in both the product yield (99%) and the enantioselectivity (81% ee) when cyclopentyl methyl ether was used as a solvent. A plausible reaction intermediate was discussed. (C) 2012 Elsevier B. V. All rights reserved.

DOI： 10.1016/j.jorganchem.2012.12.015

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

A series of highly tunable, functionalized azolium compounds have been synthesized from chiral alpha-amino acid derivatives such as beta-amino alcohols or alpha-amino esters. The combination of a Cu salt and a chiral azolium efficiently facilitated the asymmetric conjugate addition (ACA) reactions of acyclic enones with dialkylzinc under ambient conditions without temperature control. Of the (hydroxy amide)-functionalized azolium ligand precursors, which were derived from beta-amino alcohols, an azolium salt containing a tert-butyl group as the stereodirecting group was found to be the best choice of ligand. Ligand screening revealed that the use of an azolium salt containing a sterically bulky alkyl substituent such as N-CHRR' on the azolium ring led to a marked increase in the enantioselectivity of the ACA reaction. Thus, a new efficient (hydroxy amide)-functionalized azolium ligand precursor such as 26, which was prepared from 1-(diphenylmethyl)benzimidazole and (S)-tert-leucinol, has been developed. The treatment of benzalacetone (30) with Et2Zn in the presence of catalytic amounts of [Cu(OTf)]2(C6H6) and 26 at room temperature gave the corresponding 1,4-adduct 31 with excellent enantioselectivity (92?% ee). On the other hand, the enantioselectivity of the ACA reactions of acyclic enones with dialkylzinc was successfully reversed by the use of (ester amide)-functionalized azolium salts, which were obtained from alpha-amino esters. Several functionalized azolium ligand precursors from readily available serine esters have been designed and synthesized. Finally, it was found that 30 could react with Et2Zn under the influence of a bis(hexafluoroacetylacetonato)copper(II) salt and C2-symmetric azolium salt 36 to afford ent-31 in almost quantitative yield with 89?% ee. A plausible reaction mechanism for the switching of the stereoselectivity in the ACA reaction by these two functionalized azolium compounds is described.

DOI： 10.1002/ejoc.201201082

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

A series of hydroxy-amide functionalized azolium salts have been designed and synthesized for Cu-catalyzed asymmetric conjugate addition reaction. The (CH2)(2)-bridged hydroxy-amide functionalized azolium ligand precursors 2, in addition to the previously reported CH2-bridged azolium salts 1, have been prepared from readily available enantiopure beta-amino alcohols. The combination of a Cu species with 1 or 2 efficiently promoted the 1,4-addition reaction of cyclic enones with dialkylzincs. For example, the reaction of 2-cyclohepten-1-one (17) with Bu2Zn in the presence of catalytic amounts of Cu(OTf)(2) and 1 gave (S)-3-butylcycloheptanone (20) in 99% yield and 96% ee. On the other hand, when the reaction was carried out under the influence of Cu(OTf)(2) combined with 2, (R)-20 in preference to (S)-20 was obtained in 98% yield and 80% ee. In this manner, the enantioselecvity was switched by controlling the structure of chiral ligand. Additionally, the reversal of enantioselectivity was also achieved by changing the Cu precatalyst from Cu(OTf)(2) to Cu(acac)(2) with the same ligand. The combination of Cu(acac)(2) with CH2-bridged azolium salt 1 in the reaction of 17 with Bu2Zn led to formation of (R)-20 as a major product in 55% yield and 80% ee. This result was in contrast to the Cu(OTf)(2)/1 catalytic system, where the 1,4-adduct with opposite configuration was obtained. Moreover, use of the Cu(acac)(2)/2 catalytic system produced (S)-20, while (R)-20 was formed by the Cu(OTf)(2)/2 catalytic system. Thus, it was found that either varying the linker of the chiral ligands or changing the counterion of Cu species between a OTf and acac ligand initially on the metal led to dual enantioselective control in the 1,4-addition reaction.

DOI： 10.1021/jo300472r

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

A new chiral N-heterocyclic carbene (NHC) ligand derived from a natural alpha-aminoester has been designed and synthesized. The coupling of N-methylbenzimidazole with an alpha-chloroacetamide derivative, which was prepared from chloroacetyl chloride and (S)-serine methyl ester, gave the corresponding ester/amide-functionalized azolium compound 20. The reaction of 2-cyclohexen-1-one (17) with Et2Zn in the presence of catalytic amounts of Cu(OTf)(2) and 20 produced (R)-3-ethylcyclohexanone (18) as a major product. In contrast, the enantioselective conjugate addition (ECA) reaction catalyzed by Cu(OTf)(2) under the influence of a hydroxy-amide-functionalized azolium compound 15, which was derived from (S)-tert-leucinol, produced (S)-18 in preference to (R)-18. A series of azolium salts were synthesized from (S)-serine esters, and the reaction conditions for the ECA reaction were optimized to produce (R)-18 with 69% ee. The best results were obtained in the case of the reaction of 4,4-dimethyl-2-cyclohexen-1-one (34) with Et2Zn catalyzed by Cu(OTf)(2) in combination with azolium compounds. When the reaction of 34 with Et2Zn was carried out in the presence of catalytic amounts of Cu(OTf)(2) and 20, (S)3-ethyl-4,4-dimethylcyclohexanone (35) was obtained with 97% ee, whereas the ECA reaction under the influence of hydroxy-amide-functionalized azolium 15 afforded (R)-35 with &gt;99% ee. In this manner, the reversal of enantioselectivity was achieved by controlling the structure of chiral ligands. (C) 2011 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2011.04.028

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

An enantioselective hydrosilylation of prochiral ketones was achieved by using a catalytic amount of the readily accessible and air- and moisture-stable iridium complex [IrCl(cod)(NHC)] at room temperature.

DOI： 10.1002/adsc.201100897

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

A new monodentate iridium(III) complex bearing a readily accessible and tunable chiral hydroxy-amide functionalized N-heterocyclic carbene ligand, Cp*lr(NHC)Cl-2, has been synthesized and characterized by crystallographic methods. The monodentate Cp*lr(NHC)Cl-2 complex was found to act as a catalyst precursor for the stereoselective transfer hydrogenation of acetophenone in the presence of KOH even at room temperature. Moderate enantioselectivity was observed in the initial screening of the chiral ligands. (C) 2011 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2011.10.057

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DOI： 10.1016/j.jourganchem.2011.02.009

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

A new chiral N-heterocyclic carbene (NHC) ligand was designed. Thus, an efficient synthetic route to C-2-symmetric bis(hydroxyamide)-functionalized benzimidazolium salts from chiral beta-amino alcohols was developed. The combination of Cu(OTf)(2) and the chiral azolium compound efficiently promoted the conjugate addition reaction of cyclic enone with dialkylzinc to give the corresponding adduct in good yield. Among a series of chiral NHC proligands, the functionalized benzimidazolium chloride possessing a tert-butyl group as a stereodirecting group was found to be the best choice of ligand. Under optimized reaction conditions, an excellent enantioselectivity (96% ee) was realized by allowing 2-cyclohepten-1-one to react with Bu2Zn at room temperature. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jorganchem.2010.07.038

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Reversal of enantioselectivity in a Cu-catalyzed asymmetric conjugate addition reaction of dialkylzinc to cyclic enone with use of the same chiral ligand was successfully achieved. The reaction of 2-cyclohexen-1-one (30) with Et2Zn catalyzed by Cu(OTf)(2) in the presence fan azolium salt derived from a chiral beta-amino alcohol gave (S)-3-ethylcyclohexanone (31) in good enantioselectivity. Among a series of chiral azolium compounds examined, the benzimidazolium salt (10) having both a tert-butyl group at the stereogenic center and a benzyl substituent at the azolium ring was found to be the best choice of ligand in the Cu(OTf)(2)-catalyzed reaction. Good enantioselectivity was observed when the reaction was conducted by employing a benzimidazolium derivative rather than an imidazolium derivative. The influence of the substituent at the azolium ring on the stereoselectivity of the reaction was also examined. In addition, from the results of the reaction catalyzed by Cu(OTf)(2) combined with an azolium compound derived from (5)leucine methyl ester, it was found that the hydroxy side chain in the chiral ligand is probably crucial for the enantiocontrol of the conjugate addition reaction. On the other hand, it was discovered from a screening test of copper species that the reversal of enantioselectivity was realized by allowing 30 to react with Et2Zn in the presence of Cu(acac)(2) combined with the same ligand precursor to afford (R)-31 as a major product. The influence of the stereodirecting group at the chiral ligand on the stereoselectivity in the Cu(acae)(2)-catalyzed reaction differed completely from that observed in the Cu(OTf)(2)-catalyzed reaction. Reaction with a cyclic enone consisting of a seven-membered ring such as 2-cyclohepten-1-one (40) resulted in increasing the enantioselectivity of the reaction. Thus, treatment of 40 with Et2Zn catalyzed by Cu(OTf)(2) combined with a benzimidazolium salt produced the corresponding (5)-conjugate adduct in a 92:8 enantiomer ratio (er), while the Cu(acac)(2)-catalyzed reaction with the same ligand afforded (R)-product in a 9:91 er.

DOI： 10.1021/jo101147p

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

A simple and efficient one-pot procedure for the synthesis of alpha-diketones from aldehydes via benzoin condensation under the influence of a catalytic amount of azolium salt combined with DBU has been developed. Thus, aldehyde was allowed to react with the azolium salt/DBU catalytic system at room temperature, and then the reaction mixture was heated to 70 degrees C under air atmosphere to afford the corresponding 1,2-diketone in good yield. This would be an efficient alternative method of synthesizing alpha-diketones from alclehydes under metal-free conditions. Crown Copyright (C) 2010 Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2010.01.103

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Chiral dimeric tridentate NHC-amidate-alkoxide palladium(II) complexes, 3a and 3b, effected oxidative boron Heck-type reactions of aryl boronic acids with both acyclic and cyclic alkenes at room temperature to afford the corresponding coupling products with high enantioselectivities. The high degree of enantioselection, far superior to existing methods, stems from differences in the nonbonding interactions in the proposed transition states, due to the influence from bulky substituents of the alkene substrates and the "Counter axial groups" of the palladium(II) catalysts.

DOI： 10.1021/jo901977n

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

The synthesis of a series of azolium salts such as azolium iodides and chlorides having both N-anionic functional group and N-alkyl group have been developed. Reaction of azolium iodides or chlorides with Ag(2)O gave the corresponding NHC-Ag complexes. It was found that the resulting NHC-Ag complexes derived from azolium iodides or chlorides differ in their physical properties. The azolium chlorides as well as azolium iodides were successfully converted into the NHC-Ag complexes, which subsequently reacted with PdCl(2)(CH(3)CN)(2) to give the anionic amidate/NHC-Pd complexes. Thus, a variety of the NHC-Pd complexes could be obtained from benzimidazolium and imidazolium salts. Published by Elsevier B.V.

DOI： 10.1016/j.jorganchem.2009.10.011

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Language：Japanese   Publisher：The Japan Petroleum Institute  

DOI： 10.11523/sekiyu.2010f.0.10.0

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

While developing novel catalysts for carbon-carbon or carbon-heteroatom coupling (nitrogen, oxygen, or fluorine), we were able to introduce tridentate N-heterocyclic carbene (NHC)-amidate-alkoxide palladium(II) complexes. In aqueous solution, these NHC-Pd(II) complexes showed high ability for C-H activation of various hydrocarbons (cyclohexane, cyclopentane, dimethyl ether, tetrahydrofuran, acetone, and toluene) under mild conditions.

DOI： 10.1002/adsc.200800698

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Conjugate addition of Et(2)Zn to 2-cyclohexen-1-one catalyzed by Cu(OTf)(2) combined with an azolium salt derived from (S)-leucinol produced the corresponding (S)-adduct, while the use of Cu(acac)(2) in combination with the same ligand afforded the (R)-adduct as a major product.

DOI： 10.1039/b916103a

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Direct conversion of benzene to phenol was achieved by allowing it to react with a mixed gas of air and CO in the presence of HPMoV and a very small amount of Pd-5%/C in aqueous acetic acid at 150 degrees C for 2h. The TON of HPMoV for the formation of phenol goes up to over 1300. The active species of the present reaction is thought to be V4+ generated from HPMoV catalyst by the reduction with CO. The role of the I'd species seems to promote the generation of V4+ from HPMoV. This method is expected to provide a direct route to phenol from benzene. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.molcata.2008.04.002

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

omega-Hydroxy ketones and diketones, which are important starting materials for the synthesis of cycloalkanones and heterocyclic compounds, were prepared by the one-step reaction of methyl ketones with alpha,omega-diols under the influence of an iridium complex and a base. The selectivity of omega-hydroxy ketones and diketones could be controlled by varying the starting ratio of methyl ketones to alpha,omega-diols. For example, reaction using acetophenone (5 equiv) with respect to 1,6-hexanediol (1 equiv) in the presence of [IrCl(cod)](2), PPh3, and KOH without solvent gave 1,10-diphenyl-1,10-decanedione in almost quantitative yield, while reaction using acetophenone (1 equiv) to 1,6-hexanediol (4 equiv) led to 8-hydroxy-1-phenyl-1-octanone in 92% yield. This methodology was successfully extended to the reaction of arylacetonitriles with alpha,omega-diols leading to diaryldinitriles.

DOI： 10.1246/bcsj.81.689

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Triphosphazene, 1,3,5-triazo-2,4,6-triphosphorine-2,2,4,4,6,6-chloride (TAPC), was found to be an efficient catalyst for the Beckmann rearrangement of cyclohexanone oxime and cyclododecanone oxime to E-caprolactam and laurolactam, which are raw materials of nylon-6 and nylon-12, respectively.

DOI： 10.1021/jo702277g

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Carboxylation of benzenes with CO was successfully achieved by a combined catalytic system of Pd(OAc)(2) with H5PMo10V2O40-nH(2)O (HPMo10V2) under the influence of O-2 to form the corresponding benzoic acids in relatively high selectivity and moderate yields. The regioselectivity in the carboxylation of alkylbenzenes with CO was dominated by the steric factor rather than the electronic effect of substituents. However, the carboxylation of benzoic acid proceeded with high ortho-selectivity to give phthalic acid in preference to terephthalic acid, which shows coordination of Pd species to the carboxyl group of benzoic acid. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.molcata.2007.11.022

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Oxidative arylation of ethylene with benzene was examined by using a Pd(OAc)(2)/heteropoly acid/O(2) system under mild conditions. The reaction of benzene with ethylene in the presence of catalytic amounts of Pd(OAc)(2) combined with H(4)PMo(11)VO(40) center dot 15H(2)O (or H(3)PMo(12)O(40) center dot 30H(2)O), AcONa, and dibenzoylmethane under air at 90 - 120 degrees C produced oxidative coupling products, styrene and stilbene, in fair yields (up to 167 total turnovers). From the examination of the catalyst performance of Pd(OAc)(2) combined with various heteropoly acids, it was found that the employment of heteropoly acids including molybdenum ion in their structure is very important to obtain high turnover numbers of Pd.

DOI： 10.1039/b716425d

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

DOI： 10.1002/anie.200803793

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

A new synthetic method of substituted furoates from acrylates and aldehydes was developed by Pd-(OAc)(2) combined with molybdovanadophosphoric acid and Lewis acid under atmospheric dioxygen. The reaction was found to proceed through the palladium-catalyzed acetalization of acrylates with methanol followed by the reaction of the resulting acetals with aldehydes.

DOI： 10.1021/jo701635f

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Herein, we report an asymmetric intermolecular Heck-type reaction of acyclic alkenes by using a palladium-pyridinyl oxazoline diacetate complex under oxidative palladium(II) catalysis conditions. A premade palladium-ligand complex afforded higher enantioselectivities than a corresponding premixed palladium-ligand system, while offering enhanced asymmetric induction when compared to known intermolecular Heck-type protocols.

DOI： 10.1021/0l701584f

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

A new type of carbonylation of styrenes was achieved under a 1: 1 mixture of CO (0.5 atm) and O-2 (0.5 atm) in the presence of Pd(OAc)(2) combined with H5PMo10V2O40 center dot nH(2)O to give 4-methyl-2-phenylnaphthalen-1(4H)-one in 78 % yield. Various substituted styrenes were also carbonylated to the corresponding substituted arylnaphthalen-1(4H)-ones in moderate yields. The reaction was found to proceed in two stages involving the head-to-tail dimerization of styrenes, followed by carbonylation of the resulting dimers. Styrenes were efficiently dimerized under air (1 atm) in the absence of CO even at room temperature to produce head-to-tail dimers in good yields.

DOI： 10.1246/bcsj.80.1194

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

A new type of trisannelation reaction of acrylates through acetal formation was developed by Pd(OAc)(2) combined with molybdovanadophosphoric acid (HPMo8V4) and Lewis acid under atmospheric dioxygen. Thus, the reaction of isobutyl acrylate in the presence of Pd(OAc)(2), HPMo8V4, and CeCl3 under O-2 (1 atm) in MeOH/AcOH afforded isobutyl 1,3,5-benzenetricarboxylate in fair yield. The reaction was found to proceed through the palladium-catalyzed acetalization of acrylate with methanol followed by the trisannelation reaction of the resulting acetal promoted by CeCl3.

DOI： 10.1021/jo070323e

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Concomitant introduction of COOH and OH groups to biphenyl was achieved by allowing biphenyl to react with CO and O-2 using the Pd/molybdovanadophosphoric acid catalytic system. For instance, biphenyl reacted under a mixed gas of CO (0.5 atm) and O-2, (0.5 atm) in the presence of catalytic amounts of Pd(OAc)(2) and H5PMo10V2O40 center dot 26H(2)O in acetic acid to give the corresponding hydroxybiphenylcarboxylic acids. The reaction was found to proceed through the formation of biphenylcarboxylic acid followed by hydroxylation of the resulting carboxylic acid. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.molcata.2006.08.045

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

Lactams were successfully synthesized in the one-pot reaction of cycloalkanes and tBuONO in the presence of N-hydroxyphthalimide as a key catalyst. Cyclododecane and cyclohexane were treated with tBuONO followed by triethylamine and then cyanuric chloride in a one-pot manner to give laurolactam and epsilon-caprolactam, respectively, in good yields. The Beckmann rearrangement of oximes by cyanuric chloride was found to be accelerated by the use of 1,1,1,3,3,3-hexafluoro-2-propanol as solvent. The method provides the first successful environmentally benign direct synthetic route to lactams from cycloalkanes without the formation of any salt.

DOI： 10.1002/asia.200600187

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

alpha-Hydroxy carbon radicals generated from alcohols by the action of NHPI smoothly added to electron-deficient alkynes like acetylenedicarboxylates. For instance, the reaction of 2-propanol with dimethyl acetylenedicarboxylate afforded maleate derivative 3, 3-methoxycarbonyl-4,4-dimethyl-2-buten-4-olide (4), and a fused bis-y-butyrolactone 5 formed by further addition of 2-hydroxy-2-propyl radical to 4.

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[IrCl(cod)](2) and [Cp*IrCl(2)](2) complexes catalyzed efficiently the Guerbet reaction of primary alcohols to beta-alkylated dimer alcohols in good yields. For instance, the reaction of 1-butanol in the presence of [ Cp*IrCl(2)](2) (1 mol %), t-BuOK (40 mol %), and 1,7-octadiene (10 mol %) produced 2-ethyl1- hexanol in 93% yield. Various primary alcohols undergo the Guerbet reaction under the influence of Ir complexes to give the corresponding dimer alcohols in good yields. This method provides an alternative direct route to beta-alkylated primary alcohols which are prepared by aldol condensation of aldehydes followed by hydrogenation.

DOI： 10.1021/jo061400t

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新エネルギー・産業技術総合開発機構 平成15年度産業技術研究助成プロジェクト

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The oxidation of trimethylbenzenes was examined with air or O-2 using N,N',N"-trihydroxyisocyanuric acid (THICA) as a key catalyst. Thus, 1,2,3-, 1,2,4-, and 1,3,5-trimethylbenzenes under air (20 atm) in the presence of THICA (5 mol %), Co(OAc)(2) (0.5 mol %), Mn(OAc)(2), and ZrO(OAc)(2) at 150 degrees C were oxidized to the corresponding benzenetricarboxylic acids in good yields (81-97%). In the aerobic oxidation of 1,2,4-trimethylbenzene by the THICA/Co(II)/Mn(II) system, remarkable acceleration was observed by adding a very small amount of ZrO(OAc)2 to the reaction system to form 1,2,4-benzenetricarboxylic acid in excellent yield (97%). In contrast, no considerable addition effect was observed in the oxidation of 1,3,5-trimethylbenzene. This aerobic oxidation by the present catalytic system provides an economical and environmentally benign direct method to benzenetricarboxylic acids, which are very important polymer materials. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2005.12.079

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Radical addition of 1,3-dimethyladamantane to diethyl acetylenedicarboxylate was catalyzed by NHPI combined with Co species under O-2 to give different adducts, ethyl 2-(3,5-dimethyladamantyl)-2-oxoethanoate and a normal adduct whose ratio was found to depend on the O-2 concentration of the reaction system. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2006.05.172

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A new reductive coupling reaction of secondary amines, aldehydes, and alkynes using an iridium complex as catalyst has been developed. For example, dibutylamine was allowed to react with butyraldehyde and 1-octyne in 1,4-dioxane at 50 degrees C under the influence of a catalytic amount of [IrCl(cod)](2) to give the corresponding allylamines such as N, N-dibutyl-2-butylideneoctylamine and N, N-2-tributyl-2-octenylamine in excellent yields.

DOI： 10.1021/ol060578z

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The addition of water and alcohols to non-activated terminal alkynes was found to be promoted by an iridium complex combined with Lewis acid and phosphite. Thus, terminal alkynes reacted with water or alcohols to give ketones or ketals, respectively, in good to excellent yields. alpha,omega-Diyne like 1,7-octadiyne, was converted into 1-(2-methyl-cyclopent-1-enyl)ethanone through the intramoleculer aldol condensation of the resulting 2,7-octanedione induced by Lewis acid. (c) 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2005.12.010

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Aerobic oxidation of hydroaromatic compounds and diarylalkanes by N-hydroxyphthalimide (NHPI) under mild conditions afforded the corresponding hydroperoxides in high selectivity. Treatment of the resulting hydroperoxides with sulfuric acid followed by neutralization by a base resulted in phenol and aromatic aldehydes in high selectivity. This method provides a convenient synthetic route to aldehydes involving an aromatic moiety. (c) 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2005.12.048

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Arylphosphonates were first synthesized through a catalytic phosphonation of various arenes with dialkyl phosphites under the influence of an Mn(OAc)(2)/Co(OA(C))(2)/O-2 redox couple. For instance, the reaction of benzene with diethyl phosphite in the presence of Mn(OAc)(2) (5 mol %) and Co(OAc)(2) (1 mol %) under a mixed gas of O-2 (0.5 atm) and N-2 (0.5 atm) at 45 degrees C led to diethyl phenylphosphonate in 81% selectivity at 62% conversion. This is the first successful phosphonation of benzene with dialkyl phosphites through a catalytic radical process.

DOI： 10.1021/ol052406s

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A remarkable addition effect of bases, like AcOK, was observed in the radical addition of cyanoacetates to alkenes catalyzed by a Mn(II)/CO(II)/O-2 redox system. Thus, a carbon radical from ethyl cyanoacetate could be catalytically generated by adding AcOK to the Mn(II)/CO(II)/O-2 redox system, even at room temperature, and the resulting carbon radical readily added to 1-octene to give an adduct, ethyl 2-cyanodecanoate, in good yield, while no reaction took place at all in the absence of AcOK. Ethyl cyanoacetate added smoothly to a variety of alkenes under mild conditions in the presence of a base to lead to the corresponding adducts in fair-to-good yields. It is reasonable to assume that the base added accelerated the deprotonation from a transient carbocation intermediate generated by the one-electron oxidation of ethyl cyanoacetate by the Mn(III) ion. This method provides an alternative route to alkylation of cyanoacetates under mild conditions.

DOI： 10.1246/bcsj.78.1673

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The oxidative coupling reaction of benzene with an (x,P-unsaturated aldehyde was examined by the combined catalytic system of Pd(OAc)(2) with molybdovanadophosphoric acid (HPMoV) under atmospheric dioxygen. Thus, the reaction of benzene with acrolein under dioxygen (1 atm) by the use of catalytic amounts of Pd(OAc)(2) and H4PMo11VO40 (.) 26H(2)O in the presence of dibenzoylmethane as, a ligand in propionic acid at 90 degrees C for 1.5 h afforded cinnamaldehyde in 59% yield and beta-phenyleinnamaldehyde in 5% yield. This catalytic system was extended to the direct oxidative coupling through the C-H bond activation of various arenes with acrolein and methacrolein.

DOI： 10.1021/jo050534o

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2-Aminobenzyl alcohol reacted with 2 equiv amount of ketones under the influence of [IrCl(cod)](2) or IrCl3 and KOH without any solvent, giving the corresponding quinoline derivatives in good yields. (c) 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2005.05.013

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A new route to &alpha;-hydroxy-&gamma;-butyrolactones through three-component radical coupling of 1,3-dioxoranes, acrylates, and molecular oxygen using N-hydroxyphthalimide (NHPI) as a key catalyst has been developed. For example, the addition of 1,3dioxarane to methyl acrylate under dioxygen by NHPI followed by catalytic hydrogenation of the resulting adduct on Pd/C afforded &alpha;-hydroxy-&gamma;-butyrolactone in good yield. This method provides a facile approach to &alpha;-hydroxy-&gamma;-butyrolactones, which are difficult to synthesize by conventional methods. &COPY; 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2005.03.137

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

The cross-dimerization of an electron-rich terminal alkyne with an electron-deficient internal alkyne was promoted by an iridium complex to produce a 1:1 adduct in high regio- and stereoselectivities. This reaction was extended to various combinations of terminal alkynes with internal alkynes such as alkynyl esters and alkynyl aldehydes. The selectivity of the reaction was found to markedly depend on the ligands used. When dppe was used as a ligand, the 1:2 cross-cyclotrimerization reaction took place to form substituted benzene derivatives. A plausible reaction path was suggested based on a labeling experiment. This reaction provides a method for the production of complicated enynes which are difficult to be prepared by conventional methods.

DOI： 10.1002/adsc.200404359

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Synthesis of phenol and cyclohexanone in one pot was examined by means of the NHPI-catalyzed aerobic oxidation of cyclohexylbenzene. The aerobic oxidation of cyclohexylbenzene catalyzed by NHPI followed by treatment with sulfuric acid afforded phenol and cyclohexanone in good selectivities. Thus, the reaction of cyclohexylbenzene under atmospheric dioxygen (1 atm) by NHPI at 100 degrees C for 3 h followed by treatment with 0.3 M sulfuric acid at room temperature for 2 h resulted in phenol and cyclohexanone in 96 and 91% selectivity, respectively, at 25% conversion. This method was successfully extended to the one-pot synthesis of 4-hydroxyacetophenone and cyclohexanone. (c) 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2005.03.079

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An efficient methodology for the reductive alkylation of secondary amine with aldehyde and Et3SiH using an iridium complex as a catalyst has been developed. For example, treatment of dibutylamine with butyraldehyde and Et3SiH (a 1: 1: 1 molar amount of amine, aldehyde, and silane) in 1,4-dioxane at 75 degrees C under the influence of a catalytic amount of [IrCl(cod)](2) gave tributylamine in quantitative yield. In this reaction, no reduction of aldehyde took place. It was found that IrCl3, which is a starting material for preparation of iridium complexes such as [IrCl(cod)](2), acts as an efficient catalyst for the present reductive alkylation of amine. In addition, a cheaper, easy-to-handle, and environmentally friendly reducing reagent such as polymethylhydrosiloxane (PMHS) in place of Et3SiH was also useful. Thus, a variety of secondary amines could be alkylated by allowing them to react with aldehydes and PMHS in the presence of an iridium catalyst to afford the corresponding tertiary amines in good to excellent yields. From the deuterium label experiments, it was revealed that silane and water, generated during the formation of enamine by the reaction of amine and aldehyde, seem to behave as a hydrogen source. The catalytic cycle was discussed.

DOI： 10.1021/jo0481708

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Anisole and its homologues were carboxylated under the influence of CO and O-2 catalyzed by Pd(OAc)(2) combined with molybdovanadophosphates (HPMoV) under mild conditions to give the corresponding carboxylic acids in fair to good yields; for instance, anisole underwent the carboxylation under a mixed gas of CO (0.5 atm) and O-2 (0.5 atm) in the presence of Pd(OAc)(2) (5 mol%) and H(5)PMo(10)V(2)O(40)(.)nH(2)O (2 mol%) to form an isomeric mixture of anisic acids in good yield.

DOI： 10.1039/b411394g

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

DOI： 10.1002/anie.200462769

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科研費奨励研究

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1,3,5-Trihydroxyisocyanuric acid (THICA), which serves as an efficient radical-producing catalyst from hydrocarbons, was successfully prepared by two methods. The reaction of O-benzylhydroxyamine with phenyl chloroformate gave formbenzyloxycarbamic acid phenyl ester of which subsequent treatment with dimethylaminopyridine (DMAP) produced 1,3,5-tribenzyloxyisocyanurate leading to THICA by hydrogenation with H-2 on Pd/C. The other method involved the direct synthesis of 1,3,5-tribenzyloxyisocyanurate from O-benzylhydroxyamine and diphenyl carbonate. The aerobic oxidation of p-methylanisole catalyzed using THICA as a key catalyst afforded p-anisic acid in almost quantitative yield (&gt;99%). (C) 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2004.09.086

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[GRAPHICS]
Oxidative cross-coupling of acrylates with vinyl carboxylates was first successfully achieved by the use of a Pd(OAc)(2)/HPMoV/O-2 system in fair to good yields. For instance, the reaction of n-butyl acrylate with vinyl acetate in the presence of catalytic amounts of Pd(OAc)(2) and H(4)PMo(11)Vo(40)(.)nH(2)O under O-2 in acetic acid at 70 degreesC for 12 In afforded the corresponding cross-coupling product, n-butyl 5-(acetoxy)-2,4-pentadienoate, in 70% yield.

DOI： 10.1021/ol047971u

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A facile method for the synthesis of organophosphonates from alkenes and dialkyl phosphites was developed by the use of Mn(II) under air. Thus, the reaction of 1-octene with diethyl phosphite in the presence of Mn(OAc)(2) (5 mol %) under air at 90 degreesC led to diethyl octylphosphonate (78%) and diethyl (2-hexyl)decylphosphonate (6%). Internal alkenes such as cis-2-octene gave a regioisomeric mixture of the corresponding hydrophosphorylation products in 84% yields.

DOI： 10.1021/jo049657j

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A facile method for the synthesis of allyl alkyl ethers from alcohols with allyl acetate was developed by the use of [Ir(cod)(2)]+BF4- complex. For instance, the reaction of allyl acetate with n-octyl alcohol in the presence of a catalytic amount of [Ir(cod)(2)]+BF4- complex afforded allyl octyl ether in quantitative yield. Allyl carboxylates were also prepared by the exchange reaction between carboxylic acids and allyl acetate in good yields. The [Ir(cod)(2)]+BF4- complex catalyzed the reaction of alkyl and aromatic amines with allyl acetate to lead to the corresponding allylamines in fair to good yields.

DOI： 10.1021/jo049828k

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Language：English   Publisher：CHEMICAL SOC JAPAN  

We have found that the [(IrCl(cod)}(2)] complex catalyzes several reactions involving three-component couplings, hydrogen migration, vinyl ethers synthesis, and alpha-alkylation of ketones with alcohols, etc. Thus, the reaction of aldehydes, amines, and alkynes under the influence of a catalytic amount of [{IrCl(cod)}(2)] complex led to three-component coupling products through a new type of C-H bond activation adjacent to the nitrogen atom of imines. Aziridines were also synthesized by three-component couplings of aldehydes, amines, and ethyl diazoacetate in the presence of a catalytic amount of [{lrCl(cod)}(2)]. An innovation in the synthesis of vinyl ethers, which are very useful monomer materials in polymer syntheses but have been difficult to synthesize so far, was made by a simple exchange reaction of alcohols with vinyl acetates through a catalytic process using [(IrCl(cod)}(2)]. A unique alpha-alkylation of ketones with alcohols was successfully achieved under the influence of [{IrCl(cod)}(2)] and KOH without any solvents, leading to saturated ketones that elongated the carbon chain. Allyl homoallyl and diallyl ethers were converted by [{IrCl(cod)}(2)] into gamma, delta-unsaturated aldehydes via a Claisen rearrangement of in situ-generated allyl vinyl ethers. These reactions provide a novel synthetic tool for important chemicals like vinyl ethers and ketones, which are practically synthesized in the chemical industry.

DOI： 10.1246/bcsj.77.909

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The direct oxidative coupling reaction of benzenes with alkenes bearing an electron-withdrawing group was successfully achieved by the use of Pd(OAc)(2)/molybdovanadophosphoric acid (HPMoV) as the key catalyst under O-2 or air atmosphere. Thus, the reaction of benzene with ethyl acrylate under air (1 atm) assisted by Pd(OAc)(2)/HPMoV afforded ethyl cinnamate as a major product in satisfactory yield (74%). This catalytic system could be extended to the coupling reactions between various substituted benzenes and alkenes through the direct aromatic C-H bond activation. In the reaction of benzene with ethyl acrylate under O-2 (1 atm), the best turn-over number (TON) of Pd(OAc)2 reached was 121. This reaction provides a green route to cinnamate derivatives, which are important precursors of a variety of pharmaceuticals.

DOI： 10.1021/jo035568f

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Naphthalenediols were successfully synthesized in a one-pot reaction through the oxidation of diisopropylnaphthalenes with air catalyzed by N-hydroxyphthalimide (NHPI) combined with azobisisobutyronitrile (AIBN) followed by decomposition with sulfuric acid. Thus, the oxidation of 2,6-diisopropylnaphthalene with air (20 atm) in the presence of AIBN (3 mol %) and NHPI (10 mol %) in CH3CN at 75degreesC for 21 h followed by treatment with 0.3 M H2SO4 gave 2,6-naphthalenediol in 92% yield.

DOI： 10.1002/adsc.200303168

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The coupling of amines, aldehydes and trimethylsilylacetylene was found to be promoted in the presence of a catalytic amount of [IrCl(cod)](2); 1 : 1 : 1 or 1 : 2 : 2 coupling products were obtained by allowing primary amine to react with aldehyde and trimethylsilylacetylene.

DOI： 10.1039/b404430d

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

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Language：English   Publisher：SOC SYNTHETIC ORGANIC CHEM JPN  

Innovative carbon radical generation from hydrocarbons through a catalytic process under mild conditions has been achieved by the use of N-hydroxyphthalimide (NHPI) as a catalyst. This method can be successfully applied to a wide variety of functionalizations of hydrocarbons. Thus, alkanes are converted into alcohols, ketones, carboxylic acids, nitro alkanes and alkyl sulfonic acids through alkyl radicals generated by the action of NHPI. Hydroxysilylation was first performed by the addition of hydrosilanes and oxygen to alkenes bearing electron-withdrawing substituents. A new approach to oxyalkylation based on the concomitant addition of carbon radicals derived from alkanes or alcohols and molecular oxygen to alkenes or alkynes has been described.

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N,N',N"-Trihydroxyisocianuric acid (THICA) was found to be a very efficient catalyst for the oxidation of alkylbenzenes with dioxygen. Thus, a variety of meta- and para-substituted toluenes bearing an electron-withdrawing substituent such as cyanotoluene, chlorotoluene, and toluic acid under O-2 (1 atm) in the presence of THICA (5 mol %) and Co(OAc)(2) (0.5 mol %) at 100 degreesC were smoothly oxidized to the corresponding benzoic acids in almost quantitative yields. The aerobic oxidation of toluene by THICA was compared with that by N-hydroxyphthalimide. p-Xylene was efficiently oxidized by THICA to telephthalic acid in high yield (over 95%) under mild conditions.

DOI： 10.1021/jo034313z

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Radical addition of aldehydes and masked aldehydes like 1,3-dioxolanes to electron-deficient alkenes was achieved by the use of catalytic amounts of BPO and N-hydroxyphthalimide (NHPI) as a polarity-reversal catalyst under mild conditions. Three-component radical coupling of 1,3-dioxolanes, maleates, and alkenes was performed in the presence of BPO and NHPI under similar conditions. (C) 2003 Elsevier Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(03)01375-3

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

A novel strategy for production of mono- and dicarboxylic acids by the addition of carboxyalkyl radicals to alkenes and dienes, respectively, was successfully developed through a catalytic process with use of Mn(II)/CO(II)/O-2 system. Thus, a variety of carboxylic acids were prepared by the reaction of alkenes and dienes with acid anhydrides in the presence of a very small amount of Mn(OAc)(2) (0.5 mol %) and Co(OAc)(2) (0.1 mol %) under dilute dioxygen.

DOI： 10.1021/jo034584+

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

Catalytic hydroxysilylation of alkenes with trialkylsilane under dioxygen through a radical process was successfully achieved by the use of N-hydroxyphthalimide (NHPI) as a catalyst under mild conditions. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003).

DOI： 10.1002/ejoc.200300074

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Nitrotoluenes are efficiently oxidized with air to the corresponding nitrobenzoic acids by the use of N-acetoxyphthalimide (NAPI) as a key catalyst. Thus, p- and m-nitrotoluenes under 10 atm of air in the presence of NAPI combined with Co(OAC)2 (0.5 mol%) and Mn(OAc)(2) (0.05 mol%) at 130degreesC afforded p- and m-nitrobenzoic acids in 81 and 92% yields, respectively. o-Nitrotoluene was oxidized to o-nitrobenzoic acid in 51% yield by the aid of NO(2). (C) 2003 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(03)00212-0

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DOI： 10.1021/ja028903a

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Language：English   Publisher：JAPAN PETROLEUM INST  

Molybdovanadophosphoric acids (HPMoV) and their salts (NPMoV) partly substituted with an ammonium cation are efficient reoxidation systems for the Pd(OAc)(2)-catalyzed oxidation of alkenes and arenes with molecular oxygen. Acetoxylation of various cycloalkenes to 3-acetoxy-1-cycloalkenes was performed in good yields by the Pd(OAc)(2)/NPMOV/O-2 system combined with hydroquinone. Oxidation of cyclohexene and styrene to the corresponding ketones by the same catalytic system in a mixed solvent of ethanol and water formed cyclohexanone and acetophenone, respectively, in fair to good yields. Monosubstituted alkenes such as ethyl acrylate and acrylonitrile underwent acetalization by this catalytic system to give the corresponding acetals in quantitative yields. Wacker-type oxidation of long-chain terminal alkenes by the present catalytic system was successfully achieved in the presence of a small amount of chloride ion. For example, oxidation of I-octene formed 2-octanone (83%) as the major product, and the formation of undesired 3-octanone was less than 1%. The regioselectivity and yield of ketones were improved by dropwise addition of alkenes to the reaction system. The Pd(OAc)(2)/NPMOV/O-2 system also acts as a good oxidation system for the carbomethoxylation of alkenes. Cyclopentene was carbomethoxylated under a mixture of CO (0.5 MPa) and air (0.5 MPa) to give dimethyl cis-1,2- and cis-1,3-cyclopentanedicarboxylates in good yields. Oxidative coupling reaction of benzene to biphenyl was performed by Pd(OAc)(2) combined with HPMoV under dioxygen at 90degreesC. The best turn-over number of Pd(OAC)(2) reached 109 and the yield of biphenyl was 14.3% based on the benzene used.

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Enol and vinyl esters were successfully synthesized by the use of an iridium complex as a catalyst. The reaction of carboxylic acid with terminal alkynes in the presence of catalytic amounts of [Ir(cod)Cl](2) and Na2CO3 gave the corresponding I-alkenyl esters. The addition of carboxylic acids to alkynes principally took place in the Markovnikov fashion. In addition, by the use of an Ir complex combined with NaOAc various vinyl esters were prepared through the transvinylation between carboxylic acids and vinyl acetate. (C) 2002 Elsevier Science Ltd. All rights reserved.

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A methodology for the preparation of e-caprolactam (CL) precursors like 1,1'-peroxydicyclohexylamine (PDHA) and/or cyclohexanone oxime from K/A-oil (a mixture of cyclohexanone and cyclohexanol) has been established by the use of N-hydroxyphthalimide (NHPI) as a key catalyst. Thus, the aerobic oxidation of K/A-oil catalyzed by NHPI followed by treatment with ammonia afforded CL precursors in high selectivities.

DOI： 10.1039/b300354j

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Head-to-tail dimerizations of acrylates and vinyl ketone were successfully performed by the use of iridium complexes in good yields. An iridium hydride complex generated in situ from [IrCl(cod)](2) and alcohols in the presence of Na2CO3 and (MeO)(3)P was found to be an active species promoting the head-to-tail dimerization of acrylates. Thus, butyl acrylate afforded the corresponding head-to-tail dimer in 86% yield.

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Selective Wacker-type oxidation of long-chain terminal alkenes to methylketones was successfully achieved by using Pd(OAC)(2)/molybdovanadophosphate (NPMoV)/O-2 system. The selectivity of the reaction increased by slow addition of the alkenes to the catalytic solution. The oxidation of alpha,omega-dienes was also examined, and the selectivity of the oxidation was found to depend on the chain length of the dienes used. (C) 2002 Elsevier Science Ltd. All rights reserved.

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Aerobic oxidation of ethane to acetic acid was successfully performed through a catalytic radical process using N,N'-dihydroxypyromellitimide (NDHPI) combined with a Co(II) salt in acetonitrile or propionic acid. The turnover number of NDHPI reached 9.5 in acetonitrile and 15.3 in propionic acid. (C) 2002 Elsevier Science Ltd, All rights reserved.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Nitration of light alkanes and the alkyl side-chain of aromatic compounds with NO2 and HNO3 was successfully achieved by the use of N-hydroxyphthalimide (NHPI) as a catalyst under relatively mild conditions. For example, the nitration of propane with NO2 catalyzed by NHPI at 100 degreesC for 14 h gave 2-nitropropane in good yield without formation of 1-nitropropane and cleaved products such as nitroethane and nitromethane. Various aliphatic nitroalkanes, which are difficult to prepare by conventional methods, could be selectively obtained by means of the present methodology by using NHPI as the key catalyst. In addition, the side-chain nitration of alkylbenzenes such as toluene was selectively carried out to lead to alpha-nitrotoluene without the ring nitration. The present reaction provides an efficient selective method for the nitration of light alkanes and alkylbenzenes, which has been very difficult to carry out so far.

DOI： 10.1021/jo025632d

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Oxidative carbomethoxylation of cyclopentene (1) under carbon monoxide and air by the use of a catalytic amount of Pd(OAc)(2) and molybdovanadophosphate (NPMoV) led to dimethyl cis-1,2-cyclopentanedicarboxylate (2) and dimethyl cis-1,3-cyclopentanedicarboxylate (3) in good yields. Total yields of 2 and 3 were found to be improved by adding a small amount of NH4Cl. Several alkenes were similarly converted into the corresponding dimethyl dicarboxylates. The role of Cl- in the present catalytic system is suggested.

DOI： 10.1021/jo0255779

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The reaction of various others with alkenes bearing an electron-withdrawing substituent in the presence of N-hydroxyphthalimide combined with Co(OAc)(2) under dioxygen produced the corresponding adducts in which oxygen is incorporated to alkenes in good yields. Oxcetane, furan and pyrane smoothly added to ethyl fumarate even at room temperature to give coupling products in high yields. An acyclic ether like dibutyl ether also added to fumarate under mild conditions to give a hydroxylated adduct in satisfactory selectivity. (C) 2002 Published by Elsevier Science Ltd.

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DOI： 10.1021/ja0173932

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The radical addition of enolizable carbonyl compounds such as malonates and malononitrile to alkenes was successfully achieved through a catalytic process using the Mn(II)/Co(II)/O-2 system to afford the corresponding adducts in fair to good yields. Dimethyl malonate added to 1,5-cyclooctadiene to produce a fused bicycle compound.

DOI： 10.1021/jo0162282

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The first Ritter-type reaction of alkylbenzenes with nitriles has been succesfully achieved by the use of N-hydroxyphthalimide (NHPI) as a key catalyst. Thus, treatment of ethylbenzene with ammonium hexanitratocerate(IV) (CAN) in the presence of a catalytic amount of NHPI in EtCN under argon produced the corresponding amide in good selectivity.

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Aerobic oxidation of methylquinolines was successfully achieved by the use of N-hydroxyphthalimide/Co(OAc)(2)/Mn(OAc)(2) as catalyst in the presence of a small amount of nitrogen dioxide as an initiator.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

An efficient approach to phenols and aldehydes through the formation of hydroperoxides from alkylbenzenes was successfully achieved by aerobic oxidation using N-hydroxyphthalimide (NHPI) as a catalyst. The oxidation of various alkyl, benzenes with dioxygen by NHPI followed by treatment with a Lewis acid or triphenylphosphine led to phenols or aldehydes, respectively, in good yields. For example, the aerobic oxidation of cumene in the presence of a catalytic amount of NHPI at 75degreesC and subsequent treatment with H2SO4 gave phenol in 77% yield. 1,4-Dihydroxybenzene (61%) and 4-isopropylphenol (33%) were obtained from 1,4-disopropylbenzene. On the other hand, dibenzyl ether was converted into phenol or benzaldehyde upon treatment of the resulting hydroperoxide with InCl3 or PPh3, respectively.

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DOI： 10.1021/jo0158276

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A novel catalytic method for the radical addition of alkanes and molecular oxygen to electron-deficient alkenes was achieved by the use of N-hydroxyphthalimide (NHPI) combined with a Co species as the catalyst. This reaction is referred to as oxyalkylation of alkenes with alkanes and O(2). For instance, the reaction of 1,3-dimethvladamantane with methyl acrylate under molecular oxygen in the presence of catalytic amounts of NHPI and Co(acac)(3) at 70 degreesC for 16 h gave oxyalkylated products in 91% yield. Other alkenes such as fumarate and acrylonitrile also serve as good acceptors of alkyl radicals and O(2) to afford the corresponding adducts in high yields. The generality of the present reaction was examined between various alkanes and alkenes under dioxygen. The behavior of Co ions during the reaction course was discussed. The present reaction involves (i) an alkyl radical generation via hydrogen abstraction of alkane by phthalimide N-oxyl generated in situ from NHPI and O(2) assisted by Co(II), (ii) the addition of the resulting alkyl radical to an electron-deficient alkene to form an adduct radical, (iii) trapping of the adduct radical by O(2) yielding a hydroperoxide, and (iv) the decomposition of the hydroperoxide by Co ions to form an adduct in which a hydroxy or a carbonyl function is incorporated.

DOI： 10.1021/jo0157977

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An innovation of the aerobic oxidation of hydrocarbons through catalytic carbon radical generation under mild conditions was achieved by using N-hydroxyphthalimide (NHPI) as a key compound. Alkanes were successfully oxidized with O(2) or air to valuable oxygen-containing compounds such as alcohols, ketones, and dicarboxylic acids by the combined catalytic system of NHPI and a transition metal such as Co or Mn. The NHPI-catalyzed oxidation of alkylbenzenes with dioxygen could be performed even under normal temperature and pressure of dioxygen. Xylenes and methylpyridines were also converted into phthalic acids and pyridinecarboxylic acids, respectively, in good yields. The present oxidation method was extended to the selective transformations of alcohols to carbonyl compounds and of alkynes to ynones. The epoxidation of alkenes using hydroperoxides or H(2)O(2) generated in situ from hydrocarbons or alcohols and O(2) under the influence of the NHPI was demonstrated and seems to be a useful strategy for industrial applications. The NHPI method is applicable to a wide variety of organic syntheses via carbon radical intermediates. The catalytic carboxylation of alkanes was accomplished by the use of CO and O(2) in the presence of NHPI. In addition, the reactions of alkanes with NO(2) and SO(2) catalyzed by NHPI provided efficient methods for the synthesis of nitroalkanes and sulfonic acids, respectively. A catalytic carbon-carbon bond forming reaction was achieved by allowing carbon radicals generated in situ from alkanes or alcohols to react with alkenes under mild conditions.

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Catalytic Baeyer-Villiger oxidation of KA-oil (a mixture of cyclohexanone and cyclohexanol) with molecular oxygen has been developed. The oxidation of KA-oil under dioxygen atmosphere in the presence of a catalytic amount of N-hydroxyphthalimide followed by treatment with indium trichloride gave epsilon -caprolactone. (C) 2001 Elsevier Science Ltd. All rights reserved.

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A new methodology for the production of terephthalic acid (3) by the aerobic oxidation of p-xylene (1) using a combined catalytic system of N-hydroxyphthalimide (NHPI)/Co(OAc)(2)/Mn(OAc)(2) was developed. The oxidation of 1 under a dioxygen atmosphere in the presence of a catalytic amount of NHPI/Co(OAc)(2)/Mn(OAc)(2) at 100 degreesC for 14h afforded terephthalic acid in 82% yield. Removal of Mn(OAc)(2) from the catalytic system resulted in considerable reduction in the yield of 3. When the oxidation of 1 was carried out under a pressure of air (30 atm) at 150 degreesC, the reaction was completed with in 3 h to give 3 in 84% yield. The oxidation of p-toluic acid (2), which can be prepared by the oxidation of 1 using the NHPI/Ca(OAc)(2) system at room temperature, by the NHPI/Co(OAc)(2)/Mn(OAc)(2) system under pressure of air (30 atm) at 150 degreesC gave 3 in 95% yield. N-Acetoxyphthalimide (NAPI) was found to require a lower catalyst loading than NHPI, but oxidation with NAPI was slower. Thus, the oxidation of 1 catalyzed by NAPI (5 mol %)/Co(OAc)(2) (0.5 mol %)/Mn(OAc)(2) (0.5 mol %) under a dioxygen atmosphere (1 atm) in acetic acid at 100 degreesC gave 5 in 80% yield.

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Catalytic nitration of alkanes with nitric acid was first successfully achieved by the use of N-hydroxyphthalimide (NHPI) under mild conditions; the key to the present nitration was found to be the in situ generation of NO2 and phthalimide N-oxyl radical by the reaction of NHPI with nitric acid.

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Hydroacylation of simple alkenes with aldehydes via a radical process was successfully achieved by the use of N-hydroxyphthalimide (NHPI) as a polarity-reversal catalyst. Thus, 5-tridecanone was obtained by the reaction of oct-1-ene with pentanal in the presence of small amounts of NHPI and dibenzoyl peroxide (BPO).

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Catalytic nitration of alkanes with nitric acid was first successfully achieved by the use of N-hydroxyphthalimide (NHPI) under mild conditions; the key to the present nitration was found to be the in situ generation of NO2 and phthalimide N-oxyl radical by the reaction of NHPI with nitric acid.

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Iridium complexes were found to promote the conversion of allyl homoallyl ethers to gamma,delta -unsaturated carbonyl compounds. For example, treatment of 1-allyl-1-allyloxycyclohexane in the presence of catalytic amounts of [Ir(cod)Cl](2), PCy3, and Cs2CO3 in toluene at 100 degreesC afforded 4-cyclohexyliden-2,3-dimethylbutanal in 74% yield. The reaction presumably proceeds through double bond migration to allyl vinyl ethers, which then undergo the Claisen rearrangement.

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Treatment of homoallylic alcohols with NaIO4/NaHSO3 reagent in aqueous t-BuOH under mild conditions produced tetrahydrofuran derivatives together with iodohydrins in a stereospecific manner. The reaction pathways of the formation of tetrahydrofurans from trans- and cis-homoallylic alcohols were found to be different. The present method provides a new approach to Various alkylated tetrahydrofuran derivatives. (C) 2000 Elsevier Science Ltd. All rights reserved.

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Selective aerobic oxidation of methylpyridines to pyridinecarboxylic acids was successfully achieved by the use of a radical catalyst, N-hydroxyphthalimide (NHPI), in the presence of Co(II) and/or Mn(II) salts. The oxidation of 3-methylpyridine by NHPI combined with Co(OAc)(2) under O-2 (1 atm) in AcOH at 100 degreesC gave 3-pyridinecarboxylic acid (76%), The reaction was found to be enhanced by addition of a small amount of Mn(OAc)(2) to the catalytic system. The reaction with 20 atm of air, catalyzed by NHPI-Co(OAc)(2)-Mn(OAC)(2) at 150 degreesC for 1 h, gave 3-pyridinecarboxylic acid (85%). 4-Methylpyridine was much less easily oxidized than 3-methylpyridine. The cooxidation of 3-methylpyridine and 4-methylpyridine by NHPI-Co(OAc)(2)-Mn(OAc)(2) at 150 degreesC for 5 h gave results that were better than those obtained from individual oxidations, forming 3-pyridinecarboxylic acid (93%) and 4-pyridinecarboxylic acid (70%). The NHPI-catalyzed oxidation of methylpyridines would provide an attractive direct method which has long been desired in the chemical industry for the manufacturing of pyridinecarboxylic acids.

DOI： 10.1021/op000061h

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Highly efficient catalytic oxidation of alcohols with molecular oxygen by N-hydroxyphthalimide (NHPI) combined with a Co species was developed. The oxidation of 2-octanol in the presence of catalytic amounts of NHPI and Co(OAc)(2) under atmospheric dioxygen in AcOEt at 70 degrees C gave 2-octanone in 93% yield. The oxidation was significantly enhanced by adding a small amount of benzoic acid to proceed smoothly even at room temperature. Primary alcohols were oxidized by NHPI in the absence of any metal catalyst to form the corresponding carboxylic acids in good yields. In the oxidation of terminal vic-diols such as 1,2-butanediol, carbon-carbon bond cleavage was induced to give one carbon less carboxylic acids such as propionic acid, while internal vic-diols were selectively oxidized to 1,2-diketones.

DOI： 10.1021/jo000760s

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The reaction of oxime esters with cyanotrimethylsilane (Me3SiCN) under the influence of a catalytic amount of lanthanide compounds produced alpha-trimethylsilyloxydinitrile derivatives in excellent yields accompanied with the formation of trimethylsilyl oxime ethers. Among the lanthanoid catalysts examined, La((OPr)-Pr-i)(3) was found to be the best catalyst. The reaction seems to proceed through the formation- of acyl cyanides as intermediates, followed by the addition of Me3SiCN to them. Additionally, the reaction of acetic anhydride with Me3SiCN catalyzed by La((OPr)-Pr-i)(3) gave 1-trimethylsilyloxyethane dinitrile. Thus, various alpha-trimethylsilyloxydinitriles were synthesized in good yields by allowing oxime esters or acid anhydrides to react with Me3SiCN in the presence of a catalytic amount of La((OPr)-Pr-i)(3).

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A new method for the synthesis of 1,3-oxazolidine derivatives has been developed. Thus, a variety of 1,3-oxazolidines was prepared by the reaction of imines with epoxides in the presence of a catalytic amount of a samarium compound such as SmI2, SmI3, or Cp*Sm-2(thf)(2). (C) 2000 Elsevier Science Ltd. All rights reserved.

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An efficient method for production of hydrogen peroxide via aerobic oxidation of alcohols was achieved by the use of N-hydroxyphthalimide (NHPI) as a catalyst. For instance, the oxidation of benzhydrol in the presence of a catalytic amount of NHPI under dioxygen (1 atm) in ethyl acetate at 75 degrees C gave H2O2 in 51% yield along with benzophenone (72%). The production of H2O2 from various alcohols was also examined. The reaction proceeds through the formation of an alpha-hydroxy hydroperoxide as a transient intermediate derived from an alcohol and dioxygen by the action of NHPI.

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Meerwein-Ponndorf-Verley-type reductive acetylation of carbonyl compounds to acetates was successfully carried out in the presence of isopropenyl acetate under the influence of a catalytic amount of Ln((OPr)-Pr-i)(3) at room temperature. Various carbonyl compounds were converted into the corresponding acetates in fair to good yields. (C) 2000 Elsevier Science Ltd. All rights reserved.

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The acetalization of terminal alkenes such as ethyl acrylate and acrylonitrile with alcohols under O-2 was efficiently achieved by Pd(OAc)(2) supported on activated carbon combined with molybdovanadophosphate (NPMoV). For example, ethyl acrylate was subjected to acetalization with EtOH acidified by CH3SO3H under O-2 (1 atm) in the presence of [8(wt%)Pd(OAc)(2)/C] and NPMoV to form ethyl 3,3 diethoxypropionate in quantitative yield.

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A new epoxidation method of olefins with hydrogen peroxide and/or a-hydroxy hydroperoxide which are generated in situ from an alcohol and molecular oxygen was developed. A variety of alkenes were smoothly epoxidized with molecular oxygen in the presence of an alcohol under the influence of hexafluoroacetone (HFA) and N-hydroxyphthalimide (NHPI) as catalysts. The reaction involves the formation of alpha-hydroxy hydroperoxide and/or hydrogen peroxide derived from 1-phenylethanol and dioxygen by the action of NHPI and the active oxygen transfer from these hydroperoxides to HFA, giving 2-hydroperoxyhexafluoro-2-propanol which serves as the actual epoxidizing agent.

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Wacker-type oxidation of cyclopentene to cyclopentanone under dioxygen atmosphere was successfully achieved by the use of Pd(OAc)(2) and molybdovanadophosphate supported on activated carbon, [Pd(OAc)(2)-NPMoV/C], catalyst. Thus, the reaction of cyclopentene under O-2 (1 atm) in aqueous acetonitrile acidified by CH3SO3H in the presence of [Pd(OAc)(2)-NPMoV/C] at 50 degrees C produced cyclopentanone in 85% yield along with a small amount of cyclopentenone (1%). (C) 1999 Elsevier Science Ltd. All rights reserved.

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A catalytic method for alpha-hydroxy carbon radical generation from alcohols has been developed and a convenient and synthetically useful approach to alpha-hydroxy-gamma-lactones constructed.

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Radical addition of ketones to alkenes catalyzed by Mn(OAc)(2) combined with Co(OAc)(2) using dioxygen as oxidant was developed; for instance, the reaction of cyclohexanone with oct-1-ene in the presence of very small amounts of Mn(OAc)(2) and Co(OAc)(2) under air (1 atm) gave 2-octylcyclohexanone in good selectivity; from styrene, a six-membered cyclic peroxide was isolated in good yield.

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A novel catalytic hydroxyacylation of alkenes using 1,3-dioxolanes and molecular oxygen has been developed, and the reaction of 2-methyl-1,3-dioxolane with methyl acrylate under dioxygen atmosphere in the presence of catalytic amounts of NHPI and Co(OAc)(2) produced the corresponding adduct in 81% yield.

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Three-component coupling reactions of aliphatic aldehydes, aliphatic amines and ethyl diazoacetate to the corresponding aziridine derivatives has been achieved by the use of [Ir(cod)Cl](2) as a catalyst under mild conditions; for instance, the reaction of n-butyraldehyde, tert-butylamine and ethyl diazoacetate in the presence of a catalytic amount of [Ir(cod)Cl](2) in THF at -10 degrees C gave 1-tert-butyl-2-ethoxycarbonyl-3-propylaziridine in 85% yield in high stereoselectivity (cis : trans = 96 : 4).

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Olefins were smoothly epoxidized under O-2 (1 atm) in the presence of a hydrocarbon such as ethylbenzene or tetralin, using N-hydroxyphthalimide (NHPI) and Mo(CO)(6) as catalyst; the present reaction involves autoxidation of the hydrocarbon assisted by NHPI and epoxidation of alkenes with the resulting hydroperoxide catalyzed by Mo(CO)(6); cis-alkene was epoxidized in a stereospecific manner to form the corresponding cis-epoxide in high yield.

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Various types of substituted alkylpyrroles were synthesized in regioselective manner by the cyclization of nitroalkenes with imines catalyzed by Sm(Oi-Pr)(3) under mild conditions. Tetrahydroindole derivative was also synthesized in fair yield by the use of cyclic nitroalkene and imine as starting material. This method provides a novel alternative route for the regioselective synthesis of substituted alkylpyrrole derivatives. (C) 1999 Elsevier Science Ltd. All rights reserved.

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A variety of vic-diols were first successfully cleaved to the corresponding aldehydes with dioxygen catalyzed by RU(PPh3)(3)Cl-2 on active carbon in fair to good yields. For example, treatment of 1,2-octandiol and 1,2-cyclooctanediol with dioxygen in the presence of Ru(PPh3)(3)Cl-2/C in PhCF3 at 60 degrees C for 15 h produced heptanal and 1,8-octanedial in 77% and 76% yields, respectively.

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Dehomologation of aldehydes has been first successfully achieved via oxidative cleavage of silyl enol ethers, derived from aldehydes and trimethylchlorosilane, using aqueous hydrogen peroxide in the presence of a catalytic amount of peroxotungstophophate (PCWP) under phase-transfer conditions. For instance, the oxidation of 1-[(trimethylsilyl)oxy]-1-octene resulting from octanal and Me3SiCl with 35% H2O2 catalyzed by PCWP in dichloromethane at room temperature afforded the one-carbon shorter aldehyde, heptanal, in 79% yield. A variety of silyl enol ethers were also converted into one-carbon shorter aldehydes in good yields. The oxidation under homogeneous conditions using tert-butyl alcohol gave hydrolysis products such as 2-oxooctanol and octanal. It is of interest that [1-(trimethylsilyl)oxy]-1,10-undecadiene involving an enol moiety and a terminal double bond afforded exclusively 9-decenal, in which the enol moiety was selectively oxidized. A plausible reaction path for the oxidative cleavage of silyl enol ethers by the present system has been suggested from the oxidation results of alpha-[(trimethylsilyl)oxy]styrene.

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An approach for partial oxygenation through a carbocation as an intermediate was successfully developed by using nitric oxide under the influence of N-hydroxyphthalimide. Thus, a variety of benzylic ethers were converted into the corresponding partially oxidized compounds, which are difficult to prepare by conventional methods, in high yields. For example, the reaction of phthalane with NO in the presence of a catalytic amount of NHPI at 60 degrees C gave phthalaldehyde in 80% yield. The reaction was found to proceed through the formation of a hemiacetal, such as 1-hydroxyphthalane. In addition, 1,3-di-tert-butoxymethyl benzene afforded 1,3-benzenedicarbaldehyde in good yield. On the other hand, isochroman was converted into 1,1'-oxodiisochromane under these reaction conditions. The reaction of ethers with NO in the presence of a NHPI catalyst is thought to proceed via the formation of a carbocation as an intermediate. A possible reaction path was suggested.

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A new approach for the epoxidation of alkenes using O-2 without any metal catalyst was developed; a variety of alkenes were epoxidized in a regio- and stereoselective manner with O-2 in the presence of benzhydrol catalyzed by N-hydroxyphthalimide and hexafluoroacetone.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Kluwer Academic/Plenum Publishers  

A practical catalytic method to convert alkanes into the corresponding oxygen-containing compounds with O2 under mild conditions using N-hydroxyphthalimide (NHPI) in the presence or absence of a transition metal was developed. Thus, cyclohexane was successfully converted into adipic acid in good conversion and selectivity by a combined catalytic system consisting of NHPI and Mn(acac)2. Lower alkane such as isobutane was converted into t-butyl alcohol (83%) under 10 atm of air by NHPI-Co(OAc)2 system. Alkylbenzene such as toluene was oxidized to benzoic acid in high yield (81%) under normal temperature and pressure of dioxygen in the presence of a catalytic amount of NHPI and Co(OAc)2. ESR measurements showed that phthalimide-N-oxyl generated from NHPI under dioxygen atmosphere is a key species in this oxidation and functions as a radical catalyst.

DOI： 10.1023/A:1019059315516

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Exposure of a mixture of adamantane and biacetyl under O-2 in the presence of Co(OAc)(2) (0.1 mol%) in AcOH led to 1-acetyladamantane (47%) and 1,3-diacetyladamantane (20%) as major products along with small amounts of adamantan-1-ol (4%) and adamantan-2-one (3%).

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Pyrroles were synthesized by three-component coupling reaction of aldehydes, amines, and nitroalkanes in the presence of a catalytic amount of a samarium species under mild conditions. The reaction is considered to involve the coupling of alpha,beta-unsaturated imines,which are provided by the samarium-catalyzed aldol-type condensation of imines generated from amines and aldehydes, with nitroalkanes. In the case of the three-component coupling of alpha,beta-unsaturated aldehydes (or ketones) with amines and nitroalkanes, alkylpyrroles were obtained by only heating in the absence of any catalyst. For instance, a mixture of butylamine, 2-butylidenecyclohexanone, and nitroethane, allowed to react at 60 degrees C for 15 h, produced isoindole, 4r, which is difficult to prepare by conventional methods, in 39% yield.

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Alkynes were successfully converted into alpha,beta-acetylenic carbonyl compounds through radical-catalyzed aerobic oxidation using N-hydroxyphthalimide (NHPI) combined with a transion metal under mild conditions.

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Aliphatic aldehydes underwent trimerization in the presence of a catalytic amount of Cp*Sm-2(thf)(2) under ambient conditions to form 1,3-diol monoesters in good yields. For example, the reaction of acetoaldehyde catalyzed by Cp*Sm-2(thf)(2) gave 4-acetoxy-2-butanol (2a) and 3-acetoxy- 1-butanol (3a) in 86% yield. (C) 1998 Elsevier Science Ltd. All rights reserved.

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Aerobic oxidation of primary alcohols to aldehydes was efficiently performed using a Ru(PPh3)(3)Cl-2/hydroquinone system under atmospheric oxygen at 60 degrees C. A primary alcohol even in the presence of a secondary one was selectively oxidized to the corresponding aldehyde in high yield. (C) 1998 Elsevier Science Ltd. All rights reserved.

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Direct conversion of cyclohexane into adipic acid was achieved by the use of the radical catalyst, N-hydroxyphthalimide (NHPI), in the presence of a small amount of a transition metal. For instance, cyclohexane could be converted into adipic acid in 73% selectivity at 73% conversion under atmospheric oxygen (1 atm) in the presence of NHPI (10 mol %) and Mn(acac)(2) (1 mol %) at 100 degrees C for 20 h, ESR measurements show that the formation of phthalimide N-oxyl generated from NHPI with O-2 was assisted by Co(II) species. Thus, the oxidation of cyclohexane to adipic acid was found to be enhanced by the addition of a small amount of Co(OAc)(2) to the NHPI/Mn(acac)(2) system. The NHPI-catalyzed oxidation of cyclohexane provides an attractive direct method which has long been desired in the chemical industry for the manufacturing of adipic acid. The present oxidation seems to be the first practical environmentally friendly process, in which nitric acid is not used as the oxidant, for the Production of adipic acid from cyclohexane.

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Highly selective aerobic oxidation of isobutane to t-butyl alcohol was successfully achieved by the use of a radical catalyst, N-hydroxyphthalimide (NHPI) in the presence of Co(II) salt under relatively mild conditions. The oxidation of isobutane by NHPI combined with Co(acac)(2) under a pressure of air (10 atm) in benzonitrile at 100 degrees C gave t-butyl alcohol in high yield (84%) along with acetone (13%). The reaction is thought to proceed via hydrogen abstraction from isobutane by the phthalimidooxyl radical (PINO), which seems to be a key active species. The formation of acetone can be explained by a partial beta-scission of the t-butoxy radical, generated from the redox decomposition of t-butyl hydroperoxide by cobalt ion. Alkyl-substituted butanes and pentanes were difficult to be oxidized selectively under these conditions because of easy degradation to smaller fragments of the resulting alkoxyl radical intermediates.

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Cp*Sm-2(thf)(2) was found to be an efficient catalyst for the synthesis of 1,3-diol diesters by the coupling reaction of aldehydes with oxime esters under mild conditions. For instance, the reaction of acetaldehyde with cyclohexanone oxime acetate catalyzed by CP*Sm-2(thf)(2) gave 1,3-diacetoxybutane in 70% yield. Treatment of acetaldehyde with isopropenyl acetate in the presence of a small amount of cyclohexanone oxime acetate and Cp*Sm-2(thf)(2) resulted in the corresponding 1,3-diol diester in good yield.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

An efficient method for the acylation of tertiary alcohols with isopropenyl acetate (1) by the use of an oxime and Cp*Sm-2(thf)(2) as catalyst was developed. Thus, various types of tertiary alcohols could be acylated with 1 in the presence of a catalytic amount of cyclohexanone oxime acetate (2) and Cp*Sm-2(thf)(2) under mild conditions to form the corresponding acetates in excellent yields. Acid-sensitive terpene alcohols such as linalool were successfully acetylated by the present method to give acetyl linalool in quantitative yield. This method enables an alternative acylation of tertiary alcohols under acid-free conditions.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

A practical catalytic method to convert alkylbenzenes into the corresponding carboxylic acids under atmospheric dioxygen at ambient temperature using a combined catalytic system consisting of N-hydroxyphthalimide (NHPI) and Co(OAc)(2) was developed. For instance, the oxidation of toluene was completed by NHPI combined with Co(OAc)(2) under an oxygen atmosphere at room temperature to give benzoic acid in 81% yield. Under these conditions, o- and p-xylenes were selectively converted into the corresponding monocarboxylic acids without the formation of the dicarboxylic acids. ESR measurements showed that Co(II) species assists in the formation of phthalimide-N-oxyl (PINO), which is a key species in this oxidation, from NHPI.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

NaBrO3 combined with NaHSO3 was found to be an excellent oxidizing reagent of alcohols, diols, and ethers under mild conditions. A variety of aliphatic and cyclic diols were selectively oxidized with satisfactory yields to the corresponding hydroxy ketones and/or diketones, which are difficult to selectively prepare due to a concomitant formation of cleaved products. For example, 2-hydroxycyclohexanone and 1,2-cyclohexanedione were selectively formed by allowing 1,2-cyclohexanediol to react with NaBrO3/NaHSO3 reagent in a selected solvent. On the other hand, an alkyl ether, such as dioctyl ether, reacted with NaBrO3/NaHSO3 in water at room temperature to give octyl octanoate in 82% yield. The same oxidation at higher temperature (60 degrees C) produced the cr-brominated ester, octyl 2-bromooctanoate, which is considered to be formed through an alkenyl alkyl ether as the intermediate. The treatment of 1-ethoxy-1-heptene with NaBrO3/NaHSO3 afforded ethyl 2-bromoheptanoate and 2-bromoheptanoic acid as the major products.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

The oxidation of vinyl and silyl enol ethers with aqueous hydrogen peroxide was first achieved by the use of peroxotungstophosphate (PCWP) as the catalyst. For example, the oxidation of 1-ethoxy-1-octene with a stoichiometric amount of 35% H2O2 in the presence of PCWP (0.5 mol %) in a mixed solvent of methanol and dichloromethane at room temperature gave 1-ethoxy-1-methoxy-2-hydroxyoctane, a synthetic equivalent of 2-hydroxyoctanal, in 70% yield. The oxidation of acyclic silyl enol ethers such as 1-[(trimethylsilyl)oxy]-1-octene under these conditions gave 1-hydroxy-2-octanone in 72% yield, while the same oxidation in dichloromethane alone resulted in cleavage of the enol double bond to form heptanal in 71% yield. Cyclic silyl enol ethers were converted into the corresponding a-hydroxy ketones in 48-71% yields under similar reaction conditions.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The reaction of adamantane under atmospheric nitric oxide in the presence of N-hydroxyphthalimide (NHPI) which serves as the radical catalyst in a mixed solvent of benzonitrile and acetic acid afforded 1-N-adamantylbenzamide as a principal product along with small amounts of 1-nitroadamantane and 1-hydroxyadamantane. On the other hand, 1-nitroadamantane was obtained in good yield upon treatment of adamantane with NO/O-2. (C) 1997 Elsevier Science Ltd.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Isophorone was smoothly oxidized with molecular oxygen by molybdovanadophosphate supported on the active carbon (NPMoV/C) to give 3-formyl-5,5-dimethyl-2-cyclohexen-1-one in relatively high selectivity. The regioselectivity of the oxidation by NPMoV/C was found to be just opposite to that of the conventional oxidations. The pore size of the supports appears to be an important factor governing the regioselectivity. (C) 1997 Elsevier Science Ltd.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Cyclotrimerization of internal and terminal alkynes was performed using a new triple catalytic system, Pd(II)/chlorohydroquinone/NPMoV, under atmospheric oxygen. Internal alkynes such as 3-hexyne and 4-octyne were converted into hexaethyl- and hexapropylbenzenes in quantitative yields. Terminal alkyne, t-butylacetylene, afforded 1,3,5-tri-t-butylbenzene without formation of unsymmetrical tri-t-butylbenzenes. The reaction did not take place in the absence of oxygen. (C) 1997 Elsevier Science Ltd.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MYU K K  

In this review, we describe a new method of generating samarium (II) species under mild conditions and new catalytic reactions using samarium (II) complexes. A samarium (II) equivalent can be efficiently generated in situ from the reaction of elemental samarium with chlorotrimethylsilane (Me3SiCl)/sodium iodide (NaI) or bromotrimethylsilane (Me3SiBr) under mild conditions. The in situ generated samarium (II) equivalent can be used for intermolecular carbon-carbon bond formation in carbonyl compounds. The reducing ability of samarium (II) species can also be controlled by changing the method by which organohalosilanes (RnSiX4-n) are combined with Sm as well as the relative ratio of organohalosilanes to Sm in the Sm/RnSiX4-n system. Sm (II) complexes such as Cp-2*Sm(thf)(2) and SmI2 catalyze a new type of 1:2 cross-coupling reaction of vinyl esters with aldehydes to afford the corresponding diesters. Alcohols and amines were acylated by vinyl esters in the presence of Cp-2*Sm(thf)(2) catalyst, giving the corresponding esters and amides in good yields. The Cp-2*Sm(thf)(2)-catalyzed acylation of tertiary alcohols is achieved by the combination of an oxime ester with a vinyl ester as an acylation agent. SmI2 also acts as a catalyst in the aldol-type condensation of imines to alpha,beta-unsaturated imines. Pyrroles are prepared by three-component coupling of aldehydes, amines and nitroalkanes in the presence of SmI2.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Molybdovanadophosphate (NPMoV)/hydroquinone/O-2 system was found to be an efficient reoxidation system in palladium-catalyzed oxidations of alkenes and related compounds. Thus, acetoxylations of cycloalkenes utilizing molecular oxygen as the final oxidant were cleanly performed using the multicatalytic system consisting of Pd(OAc)(2)/hydroquinone/NPMoV to form 3-acetoxy-1-cycloalkenes in good yields. For example, cyclopentene and cyclohexene were converted into the corresponding allylic acetates in almost quantitative yields. Omitting hydroquinone from the catalytic system led to low yields of the acetates. Acetoxylation of cyclooctene was satisfactorily achieved by replacing hydroquinone of the multicatalytic system by chlorohydroquinone. Molybdovanadophosphates, which catalyze the smooth dehydrogenation of hydroquinone to benzoquinone with dioxygen, were found to rapidly promote the present Pd(II)-catalyzed acetoxylation of cycloalkenes. By the use of a mixed solvent of ethanol and water under these conditions, Wacker type oxidations of cyclohexene and styrene were accomplished in fair to good yields. Monosubstituted alkenes such as ethyl acrylate and acrylonitrile underwent the acetalization by the present catalytic system to give the corresponding acetals in quantitative yields.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Aldol type condensation of imines has first been achieved via a catalytic process using samarium diiodide (SmI2) at room temperature to form alpha,beta-unsaturated imines in good yields. The condensation was markedly facilitated by the presence of formates or aldehydes which promote the elimination of amines from aldol adducts. It was found that the 1:2 reaction of amines with aldehydes under the influence of SmI2 also led to alpha,beta-unsaturated imines in satisfactory yields. Copyright (C) 1996 Elsevier Science Ltd

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Catalytic epoxidation of monoterpenes with aqueous hydrogen peroxide catalyzed by peroxotung-stophosphate (PCWP) under biphase conditions using chloroform as the solvent was examined. A variety of terpenes was oxidized to the corresponding monoepoxides or diepoxides in good yields under mild conditions. For example, limonene (1) was converted into limonene oxide (la) in which the cyclohexene double bond was selectively epoxidized in almost quantitative yield. The oxidation of gamma-terpinene (2) with 2.2 equiv of 35% H2O2 took place with high stereoselectivity to give cis-diepoxide 2c. In terpenes bearing electron-withdrawing groups such as neryl acetate (3), geranyl acetate (4), citral (5), and geranyl nitrile (6), the double bonds remote from the substituents were epoxidized in preference to the others. The epoxidation of linalool (9) by the present catalyst-oxidant system produced the cyclic products, hydroxy furan 9a and hydroxy pyran 9b, rather than epoxide. tert-Butyl alcohol was successfully employed as the solvent by treating a hydrogen peroxide solution of tert-butyl alcohol with MgSO4 prior to use. The regioselectivities in the epoxidation of monoterpenes can be favorably explained from the electron densities of the double bonds which were estimated using the CAChe system.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Various organic compounds were oxidized by molecular oxygen in the presence of a catalytic amount of mixed-addenda heteropolyoxometalates containing molybdenum and vanadium. The catalytic activity of the molybdovanadophosphate was found to be greatly enhanced by supporting on charcoal. The supported catalyst has high catalytic activity for oxidative dehydrogenation of benzylic and allylic alcohols to the corresponding aldehydes and ketones (46-92%), nevertheless, the non-supported catalyst was inactive for the same oxidations under these conditions. 2,3,6-Trimethylphenol was selectively oxidized to trimethyl-p-benzoquinone, which is a precursor of vitamin E, in the presence of a catalytic amount of molybdovanadophosphate. In addition, the aerobic oxidation of amines, alkyl-substituted phenols, and alkanes were also examined.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

A novel class of catalysts for alkane oxidation with molecular oxygen was examined. N-Hydroxyphthalimide (NHPI) combined with Co(acac)(n) (n = 2 or 3) was found to be an efficient catalytic system for the aerobic oxidation of cycloalkanes and alkylbenzenes under mild conditions. Cycloalkanes were successfully oxidized with molecular oxygen in the presence of a catalytic amount of NHPI and Co(acac)(2) in acetic acid at 100 degrees C to give the corresponding cycloalkanones and dicarboxylic acids. Alkylbenzenes mere also oxidized with dioxygen using this catalytic system. For example, toluene was converted into benzoic acid in excellent yield under these conditions. Ethyl- and butylbenzenes were selectively oxidized at their alpha-positions to form the corresponding ketones, acetophenone, and 1-phenyl-1-butanone, respectively, in good yields. A key intermediate in this oxidation is believed to be the phthalimide N-oxyl radical generated from NHPI and molecular oxygen using a Co(II) species. The isotope effect (k(H)/k(D)) in the oxidation of ethylbenzene and ethylbenzene-d(10) with dioxygen using NHPI/Co(acac)(2) was 3.8.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Adamantanes were successfully converted into the corresponding mono- and dihydroxy adamantanes with molecular oxygen in the presence of N-hydroxyphthalimide (NHPI) combined with cobalt salts under mild conditions. For example, exposure of adamantane under oxygen atmosphere in the presence of NHPI (10 mol%) and Co(acac)(2) (0.5 mol%) in acetic acid at 75 degrees C for 6 h afforded adamantan-1-ol (43 %) and adamantane-1,3-diol (40 %) along with adamantan-2-one (8 %) in 93 % conversion. Similarly, 1,3-dimethyladamantane produced 3,5-dimethyladamantan-1-ol (47 %) and 5,7-dimethyladamantane-1,3-diol (37 %). Copyright (C) 1996 Elsevier Science Ltd

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

NaBrO3 combined with NaHSO3 was found to be an efficent reagent for the oxidative esterification of primary alcohols. Thus, a variety of esters was prepared from primary alcohols, aldehydes, and acetals in aqueous medium under mild conditions. Treatment of alpha,omega-diols with NaBrO3/NaHSO3 reagent afforded the corresponding lactones and/or dicarboxylic acids in fair yields.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Aerobic oxidation of various alcohols has been accomplished by using a new catalytic system, N-hydroxyphthalimide (NHPI) combined with Co(acac)(3). The oxidation of alcohols by NHPI was found to be markedly enhanced by adding a slight amount of Co(acac)(3) (0.05 equiv. to NHPI). Thus, secondary alcohols and vic-diols which are difficult to be oxidized by NHPI alone were smoothly oxidized with molecular oxygen (1 atm) to the corresponding carbonyl compounds under relatively mild conditions (65 similar to 75 degrees C).

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Language：English   Publisher：AMER CHEMICAL SOC  

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Language：English   Publisher：AMER CHEMICAL SOC  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

alpha-Hydroxy ketones and vic-diols were successfully oxidized to the corresponding diketones with agueous hydrogen peroxide in the presence of a catalytic amount of peroxotungstophosphate (PCWP). This method provides a straightforward route of 1,2-diketones which are difficult to prepare by conventional oxidation of vic-diols.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

The oxidation of allenes and alkynes with hydrogen peroxide catalyzed by peroxotungstophosphate (PCWP) was examined. A variety of allenes were first converted into the corresponding alpha-ethoxy ketones upon treatment with 35% H2O2 under the influence of PCWP in a mixed solvent consisting of ethanol and dichloromethane. When the reaction was carried out using tert-butyl alcohol as a solvent, approximately a 1:1 regioisomeric mixture of alpha-hydroxy ketones was obtained along with a small amount of alpha-tert-butoxy ketone. Oxidation of internal alkynes such as 4-octyne by the PCWP-H2O2 system under phase-transfer conditions using chloroform produced alpha,beta-epoxy ketones in good yields. The same reaction in a mixed solvent of ethanol and chloroform gave alpha,beta-unsaturated ketones rather than alpha,beta-epoxy ketones. Plausible reaction paths are proposed for the oxidation of allenes and alkynes by the PCWP-H2O2 system.

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酸化反応は、化学反応における最も基本的な反応であり、実験室のみならず工業的にも極めて重要な反応である。古くからCrO3、KMnO4などの重金属塩が酸化剤として使用されてきたが、反応後、有害な金属塩の副生が避けられない。 分子状酸素は原子効率が高く、環境への負荷がない。また、コストの面でも安価であり、理想的な酸化剤である。代表的な均一系酸素酸化反応に、フリーラジカルを経由する自動酸化反応がある。この方法は、20世紀半ばに確立され、工業的にも広く利用されている重要な反応である。その他、分子状酸素を酸化剤とする酸化反応として、Wacker型酸化反応のように還元された金属触媒の再酸化剤として酸素を利用する反応、還元剤存在下、モノオキシゲナーゼを模倣した錯体を触媒として用いる反応等が知られている。しかし、これらの反応には、未だ解決しなければならない多くの問題点がある。また最近、グリーンケミストリーが一般概念として浸透してきたことから、酸素を酸化剤とする種々の有機基質の触媒的な酸化反応の研究が、活発に行われるようになっている。ここでは、 アルカンおよびアルケンの酸素酸化反応の最近の研究動向について我々の研究成果を含め紹介する。

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Language：English   Publisher：ELSEVIER SCIENCE BV  

DOI： 10.1016/j.molcata.2008.03.018

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近年、遷移金属錯体を触媒として利用する新しい方法論が次々と開発され、これまでにない新しいタイプの反応や、従来法を一新する効率的な反応が報告されている。遷移金属錯体の中でも、パラジウム(Pd)、ルテニウム(Ru)、ロジウム(Rh)を触媒として用いた反応は広く研究されている。これに対し、イリジウム(Ir)錯体を利用する反応は比較的少ない。我々の研究室では、Ir錯体を触媒に用いた新規反応の開発を目的に研究を開始し、最近いくつかの新しい反応を開発することができた。ここでは、最近の我々の研究室で開発した成果を中心に紹介する。

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Event date： 2018.11

Venue：Kyoto  

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Event date： 2018.3

Venue：日本大学 理工学部船橋キャンパス  

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Venue：日本大学 理工学部船橋キャンパス  

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Event date： 2018.3

Venue：日本大学 理工学部船橋キャンパス  

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Event date： 2018.3

Venue：日本大学 理工学部船橋キャンパス  

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Event date： 2018.3

Venue：日本大学 理工学部船橋キャンパス  

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Event date： 2018.3

Venue：日本大学 理工学部船橋キャンパス  

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Event date： 2017.3

Venue：慶應義塾大学日吉キャンパス  

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Event date： 2017.3

Venue：慶應義塾大学日吉キャンパス  

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Event date： 2016.11

Venue：台北、台湾  

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Venue：早稲田大学西早稲田キャンパス  

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Event date： 2016.9

Venue：早稲田大学西早稲田キャンパス  

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Event date： 2016.9

Venue：早稲田大学西早稲田キャンパス  

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Venue：ANAクラウンプラザホテル神戸  

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Venue：同志社大学 京田辺キャンパス  

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Venue：同志社大学 京田辺キャンパス  

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Venue：同志社大学 京田辺キャンパス  

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Venue：同志社大学 京田辺キャンパス  

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Event date： 2015.12

Venue：姫路・西はりま地場産業センター  

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Event date： 2015.11

Venue：Kyoto  

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Venue：Kyoto  

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Event date： 2015.9

Venue：三重大学  

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Venue：関西大学 吹田キャンパス  

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Venue：関西大学 吹田キャンパス  

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Venue：ユトレヒト オランダ  

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Venue：日本大学 理工学部船橋キャンパス  

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Venue：日本大学 理工学部船橋キャンパス  

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Event date： 2015.1

Venue：⼤阪科学技術センター7階701号室  

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Event date： 2014.12

Venue：じばさんビル（JR 姫路駅)  

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Venue：じばさんビル（JR 姫路駅)  

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Event date： 2014.9

Venue：九州大学  

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Venue：九州大学  

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Venue：Sapporo  

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Venue：Sapporo  

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Event date： 2012.11

Venue：Kyoto  

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Event date： 2012.11

Venue：Kyoto  

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Event date： 2012.11

Venue：Kyoto  

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Event date： 2012.9

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Venue：慶応義塾大学  

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Event date： 2012.3

Venue：慶応義塾大学  

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Venue：慶応義塾大学  

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Venue：慶応義塾大学  

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Venue：慶応義塾大学  

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Event date： 2011.12

Venue：Nara  

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Venue：Nara  

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Venue：科学技術振興機構JSTホール  

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Event date： 2011.9

Venue：つくば国際会議場  

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Event date： 2011.9

Venue：つくば国際会議場  

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Event date： 2011.9

Venue：つくば国際会議場  

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Venue：岡山理科大学  

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Venue：岡山理科大学  

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Venue：名古屋大学  

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Event date： 2011.9

Venue：名古屋大学  

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Venue：名古屋大学  

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Event date： 2011.8

Venue：大阪府立大学 中百舌鳥  

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Venue：大阪府立大学 中百舌鳥  

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Event date： 2011.7

Venue：Shanghai China  

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Event date： 2011.3

Venue：神奈川大学  

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Event date： 2011.3

Venue：神奈川大学  

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Venue：神奈川大学  

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Event date： 2011.3

Venue：神奈川大学  

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Event date： 2011.3

Venue：神奈川大学  

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Venue：神奈川大学  

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Venue：神奈川大学  

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Event date： 2010.12

Venue：Honolulu, USA  

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Venue：Honolulu, USA  

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Venue：神戸国際会議場  

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Venue：大阪国際交流センター  

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Venue：大阪国際交流センター  

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Venue：中央大学多摩キャンパス  

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Event date： 2010.9

Venue：中央大学多摩キャンパス  

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Event date： 2010.3

Venue：近畿大学 大阪  

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Venue：近畿大学 大阪  

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Venue：近畿大学 大阪  

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Venue：近畿大学 大阪  

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Venue：近畿大学 大阪  

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Event date： 2010.3

Venue：近畿大学 大阪  

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Event date： 2009.12

Venue：Seoul Korea  

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Venue：名古屋大学  

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Event date： 2009.9

Venue：宮崎大学 宮崎  

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Event date： 2009.9

Venue：同志社大学 今出川  

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Event date： 2009.9

Venue：同志社大学 今出川  

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Event date： 2009.7

Venue：グラスゴー イギリス  

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Event date： 2009.3

Venue：日本大学 船橋  

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Event date： 2009.3

Venue：日本大学 船橋  

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Event date： 2009.3

Venue：日本大学 船橋  

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Event date： 2009.3

Venue：日本大学 船橋  

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Event date： 2008.9

Venue：大阪府立大学 中百舌鳥  

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Event date： 2008.9

Venue：ラスベガス アメリカ  

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Event date： 2008.7

Venue：フィレンツェ イタリア  

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Event date： 2008.3

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Event date： 2008.3

Venue：立教大学 池袋  

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Event date： 2007.8

Venue：ボストン アメリカ  

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Event date： 2006.6

Venue：タリン エストニア  

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Event date： 2006.4

Venue：淡路島 神戸  

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Event date： 2006.4

Venue：淡路島 神戸  

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Event date： 2005.7

新エネルギー・産業技術総合開発機構 平成15年度産業技術研究助成プロジェクト

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Event date： 2005.7

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Event date： 2004.12

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Event date： 2004.7

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Event date： 2003.9

Grant-in-Aid for Encouragement of Young Scientists

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Event date： 2003.1

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Event date： 2002.9

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Event date： 2002.7

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Event date： 2000.7

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Venue：オンライン開催  

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Venue：オンライン開催  

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