Design and synthesis of diphenyldiazomethanes possessing stable aminoxyl radicals: photolytic generation of quartet species and their reaction with C60

Abstract

Diphenyldiazomethanes possessing stable tert-butylaminoxyl and Ullman’s ‘nitronyl nitroxide’§ radicals were prepared. The corresponding diphenylcarbenes substituted with the free radicals were generated by photolysis of the parent diazomethanes. From EPR fine structures and their temperature dependence, the carbene and the radical centers were shown to couple ferromagnetically in these molecules as expected from the topological symmetry of the π-framework. These diazo compounds were reacted with C₆₀ to afford a fulleroid carrying one to four nitronylaminoxyl groups.