Imminium ion chemistry at C-2 of pyroglutamates: Unexpected formation of 1,4- Methano-3-oxa-6-t-butyl-7 -azabicyc1o[7.3.0]decan-2,8-dione^†

Abstract

154-158α-Bromination of the cyclically protected S-pyroglutamic acid, its subsequent reactions with nucleophillic reagents via corresponding N-acylimminium intermediate is described