Regioselective synthesis of functionalized 1,2,3-triazoles via oxidative [3+2]-cycloaddition using Zn(OAc)2 - tBuOOH or ZnO nanoparticle as catalyst system in aqueous medium

Abstract

The regioselective synthesis of functionalized pyrazole˗1,2,3-triazoles is reported via oxidative [3+2]-cycloaddition reactions of azides with β-nitrostyrenes and chalcone derivatives using Zn(OAc)2 - tBuOOH or ZnO nanoparticles as catalyst system in aqueous medium. The catalyst dependent product selectivity was observed with β-nitrostyrenes to give the triazoles with and without -NO2 group Zn(OAc)2 and ZnO nanoparticles. The chalcones gave the triazoles selectively as sole products with good regioselectivity. The resulting products were further converted into sulfonamides and oxazoles respectively.