Effect of Higher Order Solvation and Temperature on Sn2 and E2 Reactivity (postprint)
نویسندگان
چکیده
The reactivity of microsolvated fluoride ions, F (CH3OH)0–2, with methyl, ethyl, n-propyl, and t-butyl bromide is evaluated over a broad range of temperatures. Significant decreases in reactivity are observed as either solvation or temperature increases. Increasing solvation increases sensitivity to the reaction barrier as revealed by a larger temperature dependence. These reactions are dominated by an SN2 mechanism for themethyl bromide reaction,while the SN2 and E2mechanisms compete for the reactions with ethyl and n-propyl bromide reactions. The elimination mechanism, with some association, dominates the t-butyl bromide reactions. In all cases the unsolvated bromide ion is the primary ionic product. Branching ratios are discussed in both qualitative and quantitative terms for all reactions
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