Reactions of C2ν-symmetrical C60 pentakis-adducts with diazomethane: regioselective formation of hexakis- to octakis-adducts and mechanism of methanofullerene formation by addition of diazomethane followed by dinitrogen extrusion

Abstract

Repeated treatment of the C _2ν -symmetrical C ₆₀ pentakis-adducts 1a,b with diazomethane provided with high regioselectively the novel heptakis- 5 and octakis-adducts 4a,b via hexakis-adducts 3a,b; an orbital symmetry-controlled reaction mechanism for the thermal dinitrogen extrusion from the pyrazoline intermediates in the addition of diazomethane to fullerenes is proposed.