Recent Developments in the Chemistry of Sulfur-and Nitrogen-Containing Heterocycles and Related Compounds

Abstract

Abstract Interesting ring transformation reactions of thiazolines, thiazines and related compounds are described. Thiazoline derivatives and their sulfoxides undergo ring expansion under various reaction conditions to afford the corresponding thiazine derivatives. Photochemical and thermal addition reactions of benzisothiazoles, benzothiazoles, and their derivatives with alkenes or alkynes give various types of addition products, depending on the substrates. Photochemical or metal-catalyzed ring contractions of thiazines afford thiazolines, thiazetidines, or thiazoles, respectively. Thiazine derivatives undergo ring expansion by treatment with acid or base to give the corresponding thiazepine derivatives. The stereospecificity of the ring expansion of benzothiazine sulfoxides is also described. Preparation, properties and reactions of azathiabenzene derivatives are described. Recently reported interesting reactions of thiazine derivatives and thiazine formation reactions are described.