Generation and electrophile trapping of N -Boc-2-lithio-2-azetine: Synthesis of 2-substituted 2-azetines

Abstract

s-BuLi-induced α-lithiation-elimination of LiOMe from N-Boc-3-methoxyazetidine and further in situ α-lithiation generates N-Boc-2-lithio-2-azetine which can be trapped with electrophiles, either directly (carbonyl or heteroatom electrophiles) or after transmetalation to copper (allowing allylations and propargylations), providing a concise access to 2-substituted 2-azetines. © 2014 American Chemical Society.