presence of hexamethylphosphorous triamide (HMPT) or hexaethylphosphorus triamide (HEPT) results in fullerene derivatives incorporating HMPT or HEPT ylides. The ylidederivatives exhibit unusual electronic absorptions in the visible region (435−660 nm), likely due to the presence of the ylide moiety. Electrochemical studies revealed that the first reductive potential of these compounds was more negative