Highly stereo-selective synthesis of (Z)-2,3-diiodo-1,4-diarylbut-2-ene-1,4-diones via oxidative iodination of 1,4-diarylbuta-1,3-diynes

Abstract

A novel and highly stereo and regioselective oxidative iodination of 1,4-diarylbuta-1,3-diynes promoted by N-iodosuccinamide results in (Z)-2,3-diiodo-1,4-diarylbut-2-ene-1,4-diones. In the case of NBS, the stereo-selectivity is moderate while NIS gives exclusively Z product. A plausible mechanism for the formation of both E and Z products is also proposed.