Kinetic resolution of 1-(benzofuran-2-yl)ethanols by lipase-catalyzed enantiomer selective reactions
摘要:
Kinetic resolution of racemic 1-(benzofuran-2-yl)ethanols rac-1a-d was performed by lipase-catalyzed enantiomer selective acylation (Emuch greater than100) yielding (1R)-1-acetoxy-1-(benzofuran-2-yl)ethanes (R)-2a-d and (1S)-1-(benzofuran-2-yl)ethanois (S)-1a-d in highly enantiopure form. The degree of enantiomer selectivity for enzymatic alcoholysis/hydrolysis processes starting from racemic 1-acetoxy-1-(benzofuran-2-yl)ethane rac-2 was also tested under various conditions including supercritical CO2 medium. Racemization-free lipase-catalyzed ethanolysis of the (1R)-1-acetoxy-1-(benzofuran-2-yl)ethanes (R)-2a-d yielded almost quantitatively the enantiopure (1R)-1-(benzofuran-2-yl)ethanols (R)-1a-d. (C) 2003 Elsevier Science Ltd. All rights reserved.
Optically active 1-(benzofuran-2-yl)ethanols and ethane-1,2-diols by enantiotopic selective bioreductions
摘要:
Enantiotopic selective reduction of 1-(benzofuran-2-yl)ethanones 1a-d, 1-(benzofuran-2-yl)-2-hydroxyethanones 4a-c and 2-acetoxy-1-(benzofuran-2-yl)ethanones 3a-c was performed by baker's yeast for preparation of optically active (benzofuran-2-yl)carbinols [(S)-5a-d, (S)-6a-c and (R)-6a-c, enantiomeric excess from 55 to 93% ee]. (C) 2003 Elsevier Science Ltd. All rights reserved.
Efficient Transfer Hydrogenation of Ketones using Methanol as Liquid Organic Hydrogen Carrier
作者:Nidhi Garg、Soumen Paira、Basker Sundararaju
DOI:10.1002/cctc.202000228
日期:2020.7.6
an efficient protocol for transferhydrogenation of ketones using methanol as practical and useful liquid organic hydrogen carrier (LOHC) under Ir(III) catalysis. Various ketones, including electron‐rich/electron‐poor aromatic ketones, heteroaromatic and aliphatic ketones, have been efficiently reduced into their corresponding alcohols. Chemoselective reduction of ketones was established in the presence
Reductive 3-Silylation of Benzofuran Derivatives via Coupling Reaction with Chlorotrialkylsilane
作者:Suhua Zheng、Tianyuan Zhang、Hirofumi Maekawa
DOI:10.1021/acs.joc.0c01995
日期:2020.11.6
yields under mild reaction conditions with wide substituent scope. The silyl group introduced on the five-membered ring by the reductive coupling could survive with no elimination throughout the oxidation process. The silylated heteroaromatic skeleton is useful as an intermediate in organic synthesis, and its practical utility was also demonstrated by several transformation reactions.
Enantiotopic selective reduction of 1-(benzofuran-2-yl)ethanones 1a-d, 1-(benzofuran-2-yl)-2-hydroxyethanones 4a-c and 2-acetoxy-1-(benzofuran-2-yl)ethanones 3a-c was performed by baker's yeast for preparation of optically active (benzofuran-2-yl)carbinols [(S)-5a-d, (S)-6a-c and (R)-6a-c, enantiomeric excess from 55 to 93% ee]. (C) 2003 Elsevier Science Ltd. All rights reserved.
Kinetic resolution of 1-(benzofuran-2-yl)ethanols by lipase-catalyzed enantiomer selective reactions
Kinetic resolution of racemic 1-(benzofuran-2-yl)ethanols rac-1a-d was performed by lipase-catalyzed enantiomer selective acylation (Emuch greater than100) yielding (1R)-1-acetoxy-1-(benzofuran-2-yl)ethanes (R)-2a-d and (1S)-1-(benzofuran-2-yl)ethanois (S)-1a-d in highly enantiopure form. The degree of enantiomer selectivity for enzymatic alcoholysis/hydrolysis processes starting from racemic 1-acetoxy-1-(benzofuran-2-yl)ethane rac-2 was also tested under various conditions including supercritical CO2 medium. Racemization-free lipase-catalyzed ethanolysis of the (1R)-1-acetoxy-1-(benzofuran-2-yl)ethanes (R)-2a-d yielded almost quantitatively the enantiopure (1R)-1-(benzofuran-2-yl)ethanols (R)-1a-d. (C) 2003 Elsevier Science Ltd. All rights reserved.