A bond energy scheme—II : Strain and conjugation energies in cyclic compounds

Abstract

Strain energies in certain cyclic compounds, and conjugation energies in other cyclic compounds with delocalized π-electron systems are estimated with the aid of bond energy terms, of which some have been published and some are derived in the paper. The magnitudes of the strain energies found can in general be understood in terms of likely angular or torsional strain. The magnitudes of the conjugation energies found are appreciably lower than some previous estimates of these energies; attention is drawn to the uncertainties which remain in the calculation of conjugation energies from thermochemical data.