A regioselective synthesis of 3,4-diaryl-1H-pyrazoles through a 1,3-dipolar cycloaddition of tosylhydrazones and nitroalkenes

A cycloaddition protocol that enables the regioselective synthesis of 3,4-diarylpyrazole and, for the first time, 3,4-diheteroaryl analogs is reported. The procedure employed mild conditions and easy to prepare starting materials.