Synthesis of diarylazolo[a]pyridines from [(Z)-2,4-diaryl-4-oxo-2-butenyl] azolium salts

A method for the synthesis of derivatives of [1,3]thiazolo[3,2-a]pyridines, pyrido[2,1-b][1,3]benzothiazole, [1,3,4]thiadiazolo[3,2-a]pyridine, and [1,2,4]triazolo[4,3-a]pyridine, which includes base initiated cyclization of quaternary azolium salts, formed by the interaction of (Z)-1,3-diaryl-4-bromo-2- buten-1-ones with 1-alkyl-1H-1,2,4-triazoles, 4-methyl-1,3-thiazole, 1,3-benzothiazole, and N-phenyl-1,3,4-thiadiazole-2-amine. Derivatives of 2-chloroimidazo[1,2-a]pyridine were obtained when 5-chloro-1-methyl-1H-imidazole was used.