Catalyzed β scission of a carbenium ion II – Variations leading to a general mechanism

Qingbin Li; East, Allan L. L.
September 2006
Canadian Journal of Chemistry;Sep2006, Vol. 84 Issue 9, p1159
Academic Journal
The β-scission mechanisms of catalytically chemisorbed carbenium ions are further investigated using density functional theory computations and explicit-contact modelling, but with slightly larger catalyst fragment models than in our previous work. Some variations are seen, including the existence of formal one-step and three-step (rather than two-step) mechanisms. The activation barriers are most affected by the basicity of the catalyst model than by any other characteristics: the stronger the base, the greater the barrier. A general mechanism for β scission is presented, as are the specific mechanisms for all the step variations observed from computations to date.


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