A sequence of nucleophilic ring opening of cyclopropyl ketones, N-quaternization, deprotonation, and [2,3]-sigmatropic rearrangement of ammonium ylides has been developed. This method enables efficient synthesis of bicyclic indolizidines bearing bridgehead aza-quaternary stereocenters from easily available chiral cyclopropyl ketones. The reactions proceeded with an excellent level of chirality transfer
已经开发了一系列环丙基酮的亲核开环、N-季
铵化、去质子化和
铵叶立德的 [2,3]-σ 重排。该方法能够从容易获得的手性环丙基酮中有效合成带有桥头氮杂季立体中心的双环中氮
茚。反应以优异的手性转移
水平进行,并耐受各种官能团,提供了多种具有高对映体纯度(高达 >99% ee)的烯丙基或烯丙基取代的中氮
茚。