A novel metal-free synthesis of thiazole-substituted α-hydroxy carbonyl compounds and 2-alkenylthiazoles from thiazole N-oxides and olefins

Abstract

A metal-free and highly atom-economic synthesis of thiazole-substituted α-hydroxy carbonyl compounds has been developed. Catalyzed by 5 mol% of p-toluenesulfonic acid (TsOH), a variety of thiazole-substituted α-hydroxy carbonyl compounds were obtained in moderate to good yields via 1,3-dipolar cycloaddition of thiazole N-oxides with olefins, followed by a ring-opening reaction. Furthermore, the corresponding 2-alkenylthiazoles could be produced in excellent yields from synthesized α-hydroxy carbonyl compounds through a one-pot, two-step dehydration process.