writer：Gai Jinggang, Ren Yi
keywords：S(N)2 reactions， CH3OY
source：期刊
specific source：Int. J. Quantum Chem., 2007, 107(5): 1142-1149.
Issue time：2007年

The

gas-phase nucleophilic substitution reactions at saturated oxygen X_ _ CH3OY

(X, Y _ Cl, Br, I) have been investigated at the level of CCSD(T)/6- 311_G(2df,p)//B3LYP/6-11_G(2df,p). The calculated results

indicate that X_preferably attacks oxygen atom of CH3OY via a SN2 pathway. The

central barriers and overall barriers are respectively in good agreement with

both the predictions of Marcus equation and its modification, respectively.

Central barrier heights (_HXY_ and _HYX_ ) correlate well with

the charges (Q) of the leaving groups (Y), Wiberg bond orders (BO) and the

elongation of the bonds (OOY and OOX) in the transition

structures.