Development of C2-Symmetric Pyridine N-Oxides as New Nucleophilic Catalysts and Application for the Asymmetric Synthesis

点击翻译按钮获取中文摘要

We had found an effective coupling reaction of carboxylic acids and alcohols using aromatic anhydrides by the promotion of nucleophilic base catalysts, such as DMAP and DMAPO. Furthermore, we have developed a method for the preparation of optically active carboxylic esters by the kinetic resolution of racemic secondly alcohols using carboxylic anhydrides, and achiral carboxylic acids via mixed-anhydride formation method in the presence of chiral acyl-transfer catalysts. In this study, we succeeded in preparing new pyridine oxide compounds (DM-DMAPO and DM-DMQO) and other nucleophilic base catalysts. Moreover, the following reactions were performed in the presence of any of these as a catalyst, (1) a process for producing an ester or amide compound from a carboxylic acid equivalent and an alcohol or amine, (2) an asymmetric esterification reaction, and (3) an asymmetric aldol and allylation reactions.