An environmentally benign and solvent-free synthesis of 3-aryl[1,2,4]triazolo[4,3-a]pyridines and 1-aryl-5-methyl[1,2,4]triazolo[4,3-a]quinolines using phenyliodine bis(trifluoroacetate) or iodobenzene diacetate

A simple, solvent-free and effective method for oxidative cyclization of 2-pyridyl- and 2-quinolyl-hydrazones with phenyliodine bis(trifluoroacetate) and iodobenzene diacetate to the corresponding 3-aryl[1,2,4]triazolo[4,3-a]pyridines and 1-aryl[1,2,4]triazolo[4,3-a]quinolines is described. All reactions were characterized by short reaction times and high yields at room temperature. All reactions were carried out by just grinding the reaction components.