A flexible carbanionic approach to protected trans-(2R,3S)-2-substituted 3-aminopyrrolidines: application to the asymmetric synthesis of (+)-absouline

摘要

Based on the use of phenyl thioether (3S)-7 as a synthetic equivalent to the N- and alpha-dianions (3S)-2a, a new carbanionic approach to trans-(2R,3S)-2-substituted 3-aminopyrrolidines (10) is described. Application of the method to the asymmetric synthesis of 1-aminopyrrolizidine alkaloid (+)-absouline is also reported.