Tin Powder-Promoted One-Pot Construction of alpha-Methylene-gamma-lactams and Spirolactams from Aldehydes or Ketones, Acylhydrazines, and 2-(Bromomethyl)acrylate

摘要

A concise and efficient method for the synthesis of alpha-methylene-gamma-lactams is developed from multicomponent one-pot reactions of aldehydes or ketones, hydrazides, and ethyl 2-(bromomethyl)acrylate promoted by tin powder. The reaction proceeds smoothly under mild reaction conditions without using any catalyst to give the corresponding products in high yields. alpha-Methylene-gamma-spirolactams can also be prepared from cyclic ketones.