A versatile approach to functionalisation of [60]fullerene using 3-trifluoromethyl-3-phenyldiazirine derivatives as photolabelling reagents

Abstract

The photolysis of para-substituted 3-trifluoromethyl-3-phenyldiazirine derivatives in the presence of [60]fullerene (C₆₀) allowed easy access to the functionalised methanofullerenes 2b–2d in reasonable yields. The reaction is believed to take place via the addition of the carbene intermediate to a [6,6] double bond of C₆₀. Succinimidyl-appended methanofullerene 2b serves as an active site for the attachment of other molecules via amidation. In fact, not only 2c–2d but also biotin-appended methanofullerene 2e were successfully synthesised by the amidation of 2b with the corresponding amines under mild conditions. The electrochemical properties of 2b–2d were characterised using cyclic voltammetry and differential pulse voltammetry. In addition, standard HABA assays in DMSO revealed the binding ability of the biotin moiety in 2e to avidin.