I2‐Induced Stereospecific Synthesis of 4‐Piperidones through Double Mannich Reaction and Tandem Cyclization

Abstract

AbstractAn I2‐induced double Mannich reaction and tandem cyclization of imines and ketones was investigated for the synthesis of a series of 1,2,6‐triaryl‐4‐piperidones. During the process of cyclization, only one product was produced out of four possible 4‐piperidones. Two pathways involving the balance between chelation effects and hydrogen bonding were proposed to rationalize the formation of the products, which was supported by further investigation of the reaction between β‐aminoketones and imines.