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.