Special Issue

Ei-ichi Negishi's Special Issues, Vol. 86, No. 1, 2012

65 data found. 61 - 65 listedFirst Previous
Short Paper | Special issue | Vol 86, No. 1, 2012, pp. 745 - 757
Published online: 8th August, 2012
DOI: 10.3987/COM-12-S(N)34
■ Direct Asymmetric α-Allylation of Ketones with Allylic Alcohols via Pd/Enamine Cooperative Function

Shigeo Yasuda, Naoya Kumagai,* and Masakatsu Shibasaki*

*Institute of Microbial Chemistry, 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo 141-0021, Japan

Abstract

Direct asymmetric α-allylation of ketones with allylic alcohols is described. The combination of palladium with a new phosphine ligand bearing a chiral proline moiety promoted the reaction to afford the corresponding α-allylated ketones in moderate yield and enantioselectivity.

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Short Paper | Special issue | Vol 86, No. 1, 2012, pp. 759 - 766
Published online: 6th July, 2012
DOI: 10.3987/COM-12-S(N)36
■ PALLADIUM-CATALYZED INTRAMOLECULAR HYDROARYLATION OF 6-BENZOFURANYL ALKYNOATES

Tsugio Kitamura* and Kensuke Otsubo

*Department of Applied Chemistry, Faculty of Science and Engineering, Saga University, Honjo-machi 1, Saga 840-8502, Japan

Abstract

Intramolecular hydroarylation of 6-benzofuranyl alkynoates efficiently proceeded using Pd(OAc)2 as catalyst in TFA and CH2Cl2 at room temperature. This intramolecular hydroarylation gave a mixture of regioisomers of furocoumarins, i.e., psoralens and allopsorallens.

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Short Paper | Special issue | Vol 86, No. 1, 2012, pp. 767 - 776
Published online: 17th July, 2012
DOI: 10.3987/COM-12-S(N)39
■ HYPERVALENT IODINE INDUCED OXIDATIVE CROSS COUPLING VIA Thiophene CATION RADICAL INTERMEDIATE

Toshifumi Dohi, Motoki Ito, Sho Sekiguchi, Yohei Ishikado, and Yasuyuki Kita*

*College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan

Abstract

The hypervalent iodine-induced arene cross coupling via a single- electron-transfer (SET) oxidation process could proceed in some extent even in heteroaromatic compounds, that is, several types thiophenes 1, using alkyl benzenes 2 as coupling partners. The structure of the obtainable heteroaromatic biaryl products could be elaborated by utilizing the known metal-catalyzed coupling technology, i.e., Negishi cross coupling, for the synthesis of multiple arylated (bi)thiophenes.

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Short Paper | Special issue | Vol 86, No. 1, 2012, pp. 777 - 783
Published online: 13th August, 2012
DOI: 10.3987/COM-12-S(N)61
■ Synthesis of 2-Arylbenzimidazoles in Microfluidic Chip Reactor

Ming Lei,* Wei Li, Ruijun Hu, Wan Tian, Yanguang Wang, and Hong Zhang*

*Department of Chemistry, Zhejiang University , 38 Zheda Road, Hangzhou, 310027, China

Abstract

A simple and efficient continuous flow synthesis of 2-arylbenzimidazoles from phenylenediamines and aromatic aldehydes in the presence of iodobenzene diacetate (IBD) has been developed by using a microfluidic chip reactor system. Various substituted 2-arylbenzimidazoles were obtained in high yields within 3 min under mild conditions. Compared with the classical batch systems, the present smooth procedure afforded highly selective due to the enhanced thermal and mass transfer.

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Short Paper | Special issue | Vol 86, No. 1, 2012, pp. 785 - 789
Published online: 6th August, 2012
DOI: 10.3987/COM-12-S(N)87
■ SYNTHESIS OF NEO-tANSHINLACTONE VIA THE PALLADIUM-MEDIATED INTRAMOLECULAR BIARYL COUPLING REACTION

Hitoshi Abe,* Toshitaka Kawai, Yoshinori Komatsu, Mayu Kamimura, Yasuo Takeuchi, and Yoshikazu Horino

*Department of Environmental Applied Chemistry, Faculty of Engineering, Toyama University, Gofuku 3190, Toyama 930-8555, Japan

Abstract

Neo-tanshinlactone (1) was synthesized by the intramolecular aryl-aryl coupling reaction of the precursor ester, which was prepared from the corresponding furan carboxylic acid (13) and naphthol (3), using a palladium reagent.

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65 data found. 61 - 65 listedFirst Previous