A convenient method for the conversion of hindered carboxylic acids to N-methoxy-N-methyl (Weinreb) amides

被引：45

作者：

Woo, JCS ^{[1
]}

Fenster, E ^{[1
]}

Dake, GR ^{[1
]}

机构：

[1] Univ British Columbia, Dept Chem, Vancouver, BC V6T 1Z1, Canada

来源：

JOURNAL OF ORGANIC CHEMISTRY | 2004年 / 69卷 / 25期

关键词：

D O I：

10.1021/jo048385h

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The conversion of sterically hindered carboxylic acids to N-methoxy-N-methyl amides can be efficiently carried out with 1.1 equiv of methanesulfonyl chloride, 3 equiv of triethylamine, and 1.1 equiv of N-methoxy-N-methylamine. Yields for this process range from 59% to 88%. The major byproduct in these reactions, N-methoxy-N-methylmethanesulfonamide, can be removed by placing the product mixture under vacuum for 14-24 h.

引用

页码：8984 / 8986

页数：3

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