Regioselective 1,3-Dipolar Cycloaddition in the Vinyl-1,2,4-Triazole Series: A Straightforward Approach to Bis-Heterocycles

Abstract

A novel and straightforward approach to bis-heterocyclic compounds based on 1,2,4-triazoles and isoxazolidines is presented. The synthesis of these compounds is demonstrated through regioselective 1,3-dipolar cycloaddition reactions between 5-vinyl-1,2,4-triazole and nitrone derivatives. NMR and X-ray data allowed for determining the regioselectivity of the 1,3-dipolar cycloaddition and overall topology of bis-heterocyclic architectures. Additional theoretical calculations were carried out to analyze the critical bond-forming steps in constructing the heterocycle in more detail. Finally, the experimental and theoretical data correlation was studied using Hirschfeld surfaces.