Addition of phosphoryl radicals to [76]fullerene gives six stable regioisomeric spin-adducts: MNDO/PM3 calculations of spin densities

Abstract

The addition of photochemically generated phosphoryl radicals [˙P(O)(OPrⁱ)₂] to [76]fullerene has been studied by EPR and seven out of the nineteen possible RC₇₆˙ regioisomers are obtained, six of which are stable. This compares with the previously observed addition of phosphoryl radicals to [70]fullerene which afforded three of the five expected RC₇₀˙ regioisomers (only one being stable). Semi-empirical MNDO/PM3 calculations of the energies of all nineteen HC₇₆˙ models and the unpaired electron distributions within them, were carried out in order to aid the assignment of the observed spectra to specific P(O)(OPrⁱ)₂C₇₆˙ regioisomers.