Computational note on ab initio studies of 1,3-dipolar cycloaddition reactions between 7-10 membered simple cycloalkynes and nitriloxide

The energy content in alkynes may be increased further by bending the normally linear triple bond, as in the small cycloalkynes. Cycloadditions of 1,3-dipoles may occur by concerted mechanisms. In this study, the reactivity and strain energy effect of these cycloalkynes with nitrile oxide will be discussed in light of computational studies using ab initio methods (RHF/6-31 G* and 133LYP/6-31 G* levels). The investigation of the structural properties, theoretical thermodynamic and kinetic data i.e. Delta rG, Delta G# and rate constants of the reactions at 298 degrees K will be presented. (c) 2007 Elsevier B.V. All rights reserved.