Novel and efficient method for esterification, amidation between carboxylic acids and equimolar amounts of alcohols, and amines utilizing Me2NSO2Cl and N,N-dimethylamines; its application to the synthesis of coumaperine, a natural chemopreventive dieneamide
作者:Kazunori Wakasugi、Atsushi Nakamura、Akira Iida、Yoshinori Nishii、Nobuji Nakatani、Shoji Fukushima、Yoo Tanabe
DOI:10.1016/s0040-4020(03)00734-8
日期:2003.7
(0–45°C; within 3 h) using dimethylsulfamoyl chloride (Me2NSO2Cl; 1) combined with N,N-dimethylamines (Me2NR: 2a; R=Me, 2b; R=Bu). The choice of the sulfamoyl chloride and the amine is crucial for the reaction; that is, sterically uncrowded amines accelerated the present esterification and amidation. This agent had some advantages over methanesulfonyl chloride (3)/amines as for the atom-economy, avoidance
使用二甲基氨磺酰氯(Me 2 NSO 2 Cl; 1),在非常温和的条件下(0-45°C; 3 h内),以良好的收率制备了羧酸与等摩尔量的醇或胺之间的各种羧酸酯或酰胺用N,N-二甲胺(Me 2 NR:2a; R = Me,2b; R = Bu)。氨磺酰氯和胺的选择对反应至关重要。即,空间上不拥挤的胺促进了本发明的酯化和酰胺化。该试剂比甲磺酰氯(3)/胺的原子经济性,避免了副反应,并且对羧基和羟基的化学选择性很高;通过在羧酸和醇的混合物中添加1进行实验。使用本发明的酰胺化作为关键步骤,将该方法应用于合成香豆精(一种化学预防的天然产物)。