Reactions of aryl acetates with secondary alicyclic amines in ethanol/water mixtures: Effect of the solvent composition on the kinetics and mechanism

Abstract

We report a kinetic study on the reactions of secondary alicyclic amines toward 4-nitrophenyl, 2,4-dinitrophenyl, and 2,4,6-trinitrophenyl acetates (1, 2, and 3) in ethanol/water mixtures of different compositions. It is found that (i) the intermediate in the reaction of 1 is stabilized in a mixture of 90 vol% ethanol; (ii) for the reaction of 2, the mechanism is stepwise in water but concerted in the mixtures; (iii) For the reaction of 3, the mechanism is concerted along the whole range of composition; (iv) the effect of NO 2 outweighs the solvent effect; (v) preferential solvation in the core of reaction can be ruled out. C 2011 Wiley Periodicals, Inc. Int J Chem Kinet 43: [687][688][689][690][691][692][693] 2011

Enthalpy–Entropy Correlations in Reactions of Aryl Benzoates with Potassium Aryloxides in Dimethylformamide

“…One of the most common and important reactions in organic chemistry is that of aryl esters with nucleophiles. Acyl group transfer reactions have been studied by several groups, and there is now considerable data on the kinetics and mechanisms of those processes . Two distinct reaction mechanisms, concerted A N D N and stepwise addition‐elimination A N + D N , have been suggested.…”

Kinetic study of solvent effects on the aminolysis of O‐ethyl S‐aryl dithiocarbonates

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Reaction Mechanism in Ionic Liquids: Kinetics and Mechanism of the Aminolysis of 4-Nitrophenyl Acetate

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