CF2-Driven Regioselectivity in C70 Hydrogenation
Nikita A Malkin1, Victor A Brotsman1, Natalia S Lukonina1
1Chemistry Department, M.V.Lomonosov Moscow State University, Moscow, Russia.
Abstract:
We report the theoretical modeling of the reductive hydrogenation of [6,6]-closed, [6,6]-open, and near-equatorial [5,6]-open C70(CF2)-I-III as well as the regioselective synthesis of three novel C70(CF2)H2 isomers I-III, their spectral characterization using mass spectrometry, UV/Vis, FTIR, Raman, and NMR spectroscopy. We have shown that regardless of the configuration of CF2 moiety and its position at the fullerene cage, the bridgehead carbon atoms are activated in the anionic state and undergone protonation in the presence of water. The regioselectivity of the formation of C70(CF2)H2 isomers, as well as unexpected features of suppression of the C70 hydrogenation in the presence of C70(CF2), and the high reactivity of near-equatorial [5,6]-open C70(CF2) to polyhydrogenation are discussed from kinetic and thermodynamic aspects.
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