Energetics and structural effects in the fragmentation of protonated esters in the gas phase
نویسنده
چکیده
JAN A. HERMAN and ALEX. G. HARRISON. Can. J . Chem. 59,2133 (1981). A series of formate (methyl through butyl) and acetate (methyl through pentyl) esters have been protonated in the gas phase by the Brgnsted acids H3+, N2H+, C02H+, N20H+, and HCO+. Carbonyl oxygen protonation is 87-97 kcal mol-' exothermic for H,+ and 47-57 kcal mol-' exothermic for the weakest acid HCO+, permitting a study of the effect of protonation exothermicity on the decomposition modes of the protonated esters. With the exception of protonated methyl formate, three decomposition modes, (a) to (c) are observed. OH I:.---+ R'-C-OR + R'-CEO+ + HOR (a)
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