Application of spin trapping in the study of the electrochemical and photochemical synthesis of phenylated C60 derivatives with iodonium salts

A spin trap technique was used to investigate the fullerene phenylation both electrochemically and photochemically using the reactions of iodonium salts. Phenyl radicals, produced in the cathodic reduction as well as during the photolysis of iodonium salts, were trapped by nitroso-tert-butane ( t BuNO) and nitrosodurene (ND) spin traps. However, no phenyl radicals could be detected by ESR during the irradiation of diphenyliodonium iodide, or during its electrochemical reduction, in the presence of C 60 . This indicates that prior trapping of phenyl radicals to t BuNO and ND spin trap agents, their trapping by fullerenes occurred. The radical mechanism of electrochemical and photochemical phenylation of C 60 using iodonium salts are discussed and these two phenylation techniques are compared