Chemistry at cyclopentene addends on [60]fullerene. Matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) as a quick and facile method for the characterization of fullerene derivatives

The reaction of Schwartzʹs reagent (1, (η5-C5H5)2Zr(H)Cl), and N-bromo-succinimide or m-chloroperbenzoic acid with [60]fullerene leads to the formation of Diels-Alder products with bromo- and hydroxy-cyclopentadiene, respectively. A three-step mechanism to explain this unusual reaction pathway is proposed. Epoxidation and hydrogenation of the double bond in the addend have been performed. Semi-empirical AM1 calculations are used to discuss the stereo-chemistry of the epoxides. All fullerene derivatives are characterized by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS). A routine method for the sample preparation is presented.