Selective functionalization of fullerenes with N,N-dihalosulfonamides as an N1 unit: versatile syntheses of aza[60]fulleroids and aziridino[60]fullerenes and their application to photovoltaic cells.

Highly selective and versatile methods for the synthesis of aza[60]fulleroids and aziridino[60]fullerenes from C(60) have been developed. The reactions utilized N,N-dihalosulfonamides as an N(1) source. The photophysical, electrochemical, and thermal properties of the iminofullerenes were investigated by means of UV/Vis spectroscopy, cyclic voltammetry, and thermogravimetry, respectively. Furthermore, photovoltaic cells based on the synthesized iminofullerenes were fabricated. The power conversion efficiencies (PCEs) of the devices showed moderate values ranging from 1.33 to 2.35 %.