- Reactions of carbonyl compounds in basic solutions. Part 21. The mechanisms of the alkaline hydrolysis of substituted methyl 2-(2-oxopropyl)- and 2-(2-oxo-2-phenylethyl)-benzoates and 2-(2-acetylphenyl)- and 2-(2-benzoylphenyl)-acetates
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Rate coefficients have been measured for the alkaline hydrolysis of methyl 2-[2-oxo-2-(3- or 4-substituted phenyl)ethyl]benzoates, 2-[2-(3- or 4-substituted benzoyl)phenyl]acetates,2-(2-oxopropyl) and 2-(1,1-dimethyl-2- oxopropyl)benzoates, 2-(2-acetylphenyl)acetate and 2-(2-acetylphenyl)-2,2- dimethylacetates in 70% (v/v) dioxane-water at 30.0 °C. Those for the six parent esters were also measured at 45.0 and 60.0 °C and the enthalpies and entropies of activation have been evaluated. The relative rates of hydrolysis, activation parameters and substituent effects have been used to demonstrate neighbouring participation by the keto-carbonyl groups in the alkaline hydrolysis of the esters under study. For comparable systems, participation by six-membered ring intermediates appears somewhat less advantageous than five-membered.
- Bowden, Keith,Byrne, Jane M.
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p. 2203 - 2206
(2007/10/03)
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