Development of Chiral Ureates as Chiral Strong Brønsted Base Catalysts
作者:Azusa Kondoh、Sho Ishikawa、Masahiro Terada
DOI:10.1021/jacs.9b13922
日期:2020.2.26
Recently, chiralBrønsted bases having high basicity have emerged as a powerful tool in developing new catalytic enantioselective reactions. However, such chiral strong Brønsted base catalysts are still very scarce. Herein, we report the development of a chiral anionic Brønsted base having a N,N'-dialkyl ureate moiety as a basic site. Its prominent catalytic activity was demonstrated in the enantioselective
A novel class of synthetically important glycidic esters has been obtained via an asymmetric epoxidation of trans‐α‐cyano‐α,β‐unsaturated esters catalysed by a multifunctional Cinchona alkaloid‐derived thiourea/tert‐butyl hydroperoxide (TBHP) system. The glycidic esters, isolated in excellent yield with complete trans‐diastereocontrol and high enantioselectivity, proved to be versatile building blocks