Total synthesis of (+/-)-monomorine I and (+/-)-indolizidine 195B by an aza-[2,3]-Wittig rearrangement of a vinylaziridine.

Abstract

A novel synthesis of (+/-)-monomorine I (1) and (+/-)-indolizidine 195B (2) is described in which the key step is the highly efficient aza-[2,3]-Wittig rearrangement of vinylaziridine 12 into tetrahydropyridine 13. Functional group manipulation then gave ketone 16 which could be converted into the target alkaloids by reductive amination (1:2 1.5:1).