Synthesis and Solubility Properties of Methanofullerenes Containing Primary Ammonium Ion Functionalities

The synthesis of novel methanofullerene derivatives bearing a primary ammonium ion functionality is described. They are obtained by a Bingel cyclopropanation reaction on C-60 with malonate esters, bearing both a solubilizing poly(oxyethylene) chain and an aliphatic chain ending with a BOC-protected amine. After removal of the protecting group, a counterion exchange methodology allows for the introduction of a perfluorinated anion, bringing the overall solubility of these derivatives to 98 mg/mL in an organic CH2Cl2 solution.