A thermal reaction of 2-(thiolan-2-yl)oxaziridines and related compounds. Evidence for neighbouring group participation in the displacement of oxygen by sulphur at nitrogen

Abstract

3,3-Diphenyl-2-(thiolan-2-yl)oxaziridine decomposes thermally by a first-order reaction, forming benzophenone and 5,6-dihydro-4H-1,2-thiazine. The entropy of activation (average ΔS‡–16 cal K^–1 mol^–1), solvent effects, and other results point to a mechanism involving rate-determining intramolecular attack by sulphur on the nitrogen of the oxaziridine ring. Other sulphur-containing oxaziridines behave in like manner.