Theoretical study of 1,3-dipolar cycloaddition reactions between 7–10-membered simple cycloalkynes and triazoles R–N3 (R = H, CH3, Ph)

The energy contents in alkynes may be increased further by bending the normally linear triple bond, as in the small cycloalkynes. The strain energy in the cycloalkynes increases as the size of the ring decreases. Cycloadditions of 1,3-dipoles with alkynes occur by concerted mechanisms. In this study, the reactivity and strain energy effect of the cycloalkynes with substituted 1,2,3-triazoles R–N3 (R = H, CH3, and Ph) by the use of B3LYP/6-31G** level method will be discussed. The investigation of the structured properties, theoretical thermodynamic and kinetic data, i.e., ΔrG, ΔG* and rate constants of the reactions in 298 K will be presented.