A simple and intuitive description of C-H bond energies

Thirty-five different C-H bond dissociation energies (BDEs) of cycloalkanes and cycloalkenes, including secondary, tertiary, allyl and vinyl, of hydrocarbons, bridgeheads in bicyclic hydrocarbons, difluoro, tetrafluoro, disilyl and tetrasilyl derivatives were studied computationally. It is shown that all these BDEs can be rationalized to a large extent using the hybridization of the lobe that forms the broken C-H bond and the stabilization of the radical. This rationalization is used in a semi-quantitative manner to predict BDEs based on low-level computations of the hybridization.