Photochemical reactions of thiobenzamides bearing an allylic substituent on the nitrogen atom: double-bond migration via tandem 1,4- and 1,6-hydrogen transfer

Abstract

N-(2-Phenylprop-2-enyl)thiobenzamides 1a–d underwent double-bond migration on irradiation to give N-(2-phenylprop-1-enyl)thiobenzamides 2a–d via consecutive 1,4- and 1,6-hydrogen transfer. Photoreaction of an N-(prop-2-enyl)thiobenzamide 1e and an N-(3-phenylprop-2-enyl)thiobenzamide 1f did not give migration products, but afforded pyrroles 3e and 3f and dealkylation products 4a in low yields.