| Abstract
| - Both benzylic cations and anions are strongly stabilized by chromium tricarbonyl complexation,while benzylic radicals are largely unaffected. Density functional theory calculations were performedon primary, secondary, and tertiary benzylic species to explore the effect of substitution on thestabilizing ability of the chromium tricarbonyl moiety. Complexed 1-indanyl species were alsoexamined to elucidate the effect of conformational restraint. It was found that the strong stabilizationof benzylic anions and the slight destabilization of benzylic radicals by chromium tricarbonyl areinsensitive to skeletal changes. Chromium-complexed benzylic cations, however, are highly sensitiveto changes in the organic framework, with increased substitution or constriction of conformationalmobility eroding the effect of the metal. 2-Indanyl species were also examined to study the effectof the chromium tricarbonyl fragment on homobenzylic species. It was found that the metal fragmentstabilizes distant anions by field and inductive effects and cations by a direct interaction of themetal with the cationic carbon. Homobenzylic radicals, however, do not interact with the chromiumtricarbonyl moiety and suffer a slight inductive destabilization.
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