A new three-carbon synthon for efficient synthesis of benzannelated and 1-(2-arylethenyl) heterocycles
The novel three-carbon synthon 1-(1H-1,2,3-benzotriazol-1-yl)-3-chloroacetone for the synthesis of benzothiazoles, pyrido[1,2-a]indoles, and styryl-substituted indolizines and imidazo[1,2-a]pyridines is reported. The proposed routes are a general and efficient approach for heterocyclizations followed by benzannelations or attachment of arylethenyl pharmacophores.