Synthesis and electron transporting properties of methanofullerene-o-carborane dyads in organic field-effect transistors.

A series of methanofullerene-o-carborane dyads (PCB-Ph-CB, PCB-Cn-CB, n = 1, 3, 6, 11) were synthesized via esterification of [6,6]-phenyl-C61-butyric acid (PCBA) with 2-alcohol functionalized o-carborane derivatives, 1-(4-n-BuC6H4)-2-R-1,2-closo-C2B10H10 (R = p-C6H4OH, (CH2)nOH, n = 1, 3, 6, 11). All the dyads are highly soluble in chlorinated and aromatic solvents under ambient conditions. UV-vis absorption and electrochemical reduction of the dyads exhibited features almost identical to each other, as well as to their parent PCBM, suggesting that the electronic properties of the dyads would be dominated by the methanofullerene moiety.