Stereoselective Koenigs-Knorr Glycosylation Catalyzed by Urea

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• 作者：Lifeng Sun ; Xiaowei Wu ; Dr. De-Cai Xiong and Prof. Xin-Shan Ye
• 刊名：Angewandte Chemie
• 出版年：2016
• 出版时间：July 4, 2016
• 年：2016
• 卷：128
• 期：28
• 页码：8173-8176
• 全文大小：729K
• ISSN：1521-3757

文摘

A stereoselective Koenigs–Knorr glycosylation reaction under the catalysis of urea is described. This method is characterized by urea-mediated hydrogen-bond activation and subsequent glycosylation with glycosyl chlorides or bromides. Excellent yields and high anomeric selectivity can be achieved in most cases. Moreover, the low α-stereoselectivity of glycosylations observed when using perbenzylated glucosyl donors can be greatly improved by the addition of tri-(2,4,6-trimethoxyphenyl)phosphine (TTMPP).