Ultrasound-assisted catalyst free synthesis of 1,4-/1,5-disubstituted-1,2,3-triazoles in aqueous medium

A convenient and straight forward strategy for the synthesis of 1-substituted-4-acyl-1,2,3-triazoles and 1,5-disubstituted-1,2,3-triazoles via eliminative [3 + 2] cycloaddition of azides with β-enaminones/nitroolefins is described. This catalyst free approach proceeds under ultrasound irradiation with features like broad substrates scope, short reaction time, simple work-up, high regioselectivity and large-scale synthesis.