Chiral Sulfur Compounds. XXI. Addition of Azide Ion to β-Aryl-α-phenylsulfinylacrylates

Abstract

The reaction of methyl β-aryl-α- phenylsulfinylacrylates (1) with sodium azide /acetic acid gives triazoles (6) while the reaction of (1) with sodium azide /hydrochloric acid gives β-azido esters (7a,b). Reaction of (7a) with 1,8-diazabicyclo[5.4.0]undec-7-ene, and (7b) with triethylamine gave the corresponding triazoles (6a) and (6b), respectively. Thus the formation of triazoles from the reaction of acrylates with azide ion most likely involves Michael addition of azide ion followed by cyclization of an incipient β-azido α-anion.