(Cyclopentadienyl)chromiumtricarbonyl dimers as a source of metal-centered free-radicals to form stable η2-bonded spin-adducts with fullerenes

Spin-adducts of C60 and C70 with metal-centered free radicals CpCr(CO)3 have been generated in toluene via interaction between fullerenes and the metal-metal bonded dimeric complexes [CpCr(CO)3]2 (Cp = η5-C5H5; Cp = η5-C5Me5). Their structures have been investigated using ESR spectroscopy and DFT-PBE calculations.