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N. S. Zhulyaev, I. P. Gloriozov, Yu. F. Oprunenko, J. -Y. Saillard
DFT Study of chromium tricarbonyl
complexes of coronene and kekulene
Abstract
Structure and
mechanisms of η6,η6-inter-ring haptotropic rearrangements, consisting
in shifting of organometallic group from one s-x-membered ring to another, were
investigated by means of DFT for chromium tricarbonyl complexes of coronene I
and kekulene II IIa,b and IVa,b, respectively. For both isomer pair of
complexes IIa,b and IVa,b two mechanisms differentiated by transition states
and intermediates were found. Stationary points on PPE have reduced hapticity
which is important for catalysis. These alternative mechanisms have activation
barriers (~23–25 kcal/mol), which are usually lower on ~5 kcal/mol than
corresponding activation barriers for naphthalene and other middle-size PAH
(~30 kcal/mol).
Key words: polyaromatic complexes of
chromium, density functional theory, quantum chemical modeling of reaction
mechanism, transition states and intermediates.
Copyright (C) Chemistry Dept., Moscow State University, 2002
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