Electrochemistry of adducts of 2-cyano-2-propyl radicals to C60

Thermal decomposition of azo(bisiosbutyronitrile) in a 1,2-dichloro-benzene solution of C-60 gave three isomers of I,x-di(2-cyano-2-propyl)-1,x-dihydro[60]Fullerene that were assigned 1,4-, 1,2- and unknown structures on the basis of NMR spectra. The 1,4- and unknown isomers underwent three reversible reduction steps by cyclic voltammetry. The first two redox potentials of the 1,4-isomer were the same as those of C-60, but those of the third isomer were shifted positively by 0.23 and 0.21 V from those of C-60 The heats of formation and LUMO energies of possible structures were calculated by the PM3 method. No single structure of the unknown isomer is supported by correlation of reduction potentials With LUMO energies, heats of formation, and symmetry of the C-13 NMR spectrum.