所属单位：国家糖工程技术研究中心
论文名称：Catalytic Regioselective Benzoylation of 1,2-trans-Diols in Carbohydrates with Benzoyl Cyanide: The Axial Oxy Group Effect and the Action of Achiral and Chiral Amine Catalysts
发表刊物：ACS Catalysis
刊物所在地：American Chemical Society
关键字：chiral catalyst, bifunctional thiourea catalysis, regioselective acylation, carbohydrates, vicinal trans-diols
摘要：Regioselective protection of the polyfunctionalcarbohydrates with acyl groups under catalytic conditions is aprerequisite for efficient structural modification and chain extension via glycosidation. A general and also strong “axial oxy group effect”was now observed with benzoyl cyanide as the acylating agent and
4-dimethylaminopyridine as the catalyst, permitting the preferred
O-acylation of equatorial hydroxy groups next to axial oxy groups. This effect is substantiated with 2,3-O-unprotected β-D-galacto- and α-D-glucopyranosides and 3,4-O-unprotected mannopyranosides possessing vicinal trans-diol moieties. Moreover, vicinal trans-diols with axial oxy groups next to each hydroxy group, possessing expectedly comparable reactivity, could be differentiated with chiral tertiary amine catalysts. Particularly interesting in this regard is the action of bifunctional (S,S)-N-(N,N-dialkylaminocyclohexyl)-thioureas as catalysts; they favor 2-O-benzoylation of 2,3-O-unprotected α-galactopyranosides, as is also supported by density functional theory calculations. This directing effect can be reversed with quinidine as the catalyst or with bulky substituents at the
anomeric position.
全部作者：王凤山,Rainer F. Winter
第一作者：李天路,李彤,Michael Linseis
论文类型：期刊论文
通讯作者：Richard R. Schmidt,彭鹏
卷号：10
期号：19
页面范围：11406
是否译文：否
发表时间：2020-09-01
收录刊物：SCI
发表时间：2020-09-01