Anomeric selectivity in the synthesis of galloyl esters of D-glucose
Anomeric selectivity in the synthesis of galloyl esters of D-glucose
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DOI：
10.1016/j.carres.2008.10.024
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发表时间：
2009-01-26
影响因子：
3.1
通讯作者：
Himmeldirk, Klaus B.
中科院分区：
文献类型：
--
作者：
Binkley, Robert C.;Ziepfel, Jessica C.;Himmeldirk, Klaus B.
研究了d -葡萄糖吡喃糖与没食子酸在不同条件下形成酯的选择性。建立了一个新的方案，允许在突变非常缓慢的条件下进行反应。当分别从α -或β - d -葡萄糖开始时，高度α -或β -选择性转化是可能的。由于动力学异构效应，高x选择性比高β选择性更难实现。本文提出的新方法与现有的没食子丹宁合成方法进行了比较。除了高产量和简单的纯化方案的优点，新程序独特地允许高选择性合成α产物。(C) 2008 Elsevier Ltd版权所有。
The anomeric selectivity of the ester formation between D-glucopyranose and gallic acid was investigated under a variety of conditions. A new protocol was established that allows performing the reaction under conditions where mutarotation is very slow. Highly alpha- or beta-selective transformations are possible when starting with alpha- or beta-D-glucopyranose, respectively. Due to the kinetic anomeric effect, a high (x-selectivity is more difficult to achieve than a high beta-selectivity. The new methodology presented in this article was compared with established procedures for the synthesis of gallotannins. In addition to the advantages of a high yield and an easy purification protocol, the new procedure uniquely allowed for a highly selective synthesis of alpha-products. (C) 2008 Elsevier Ltd. All rights reserved.