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8711736 
Journal Article 
Mechanism of the Reaction of Lithium Reagents with Esters 
Al-Aseer, MA; Allison, BD; Smith, SG 
1985 
Yes 
Journal of Organic Chemistry
ISSN: 0022-3263
EISSN: 1520-6904 
50 
15 
2715-2719 
English 
The kinetics and mechanism of the reactions of esters with alkyllithium reagents in cyclohexane and benzene have been investigated by infrared stopped-flow spectroscopy. Esters have been found to form complexes with sec-butyllithium, n-butyllithium, and cyclopentyllithium aggregates and the equilibrium constants for complexation were evaluated for several compounds. The rates of disappearance of esters are inversely dependent on the concentration of the lithium reagent. Complexation equilibrium constant data and rate data for the reactions of a series of substituted ethyl benzoates with sec-BuLi exhibit a substituent effect. A mechanism in which complexed ester can yield ketone and free ester can react with monomeric alkyllithium to give free ketone followed by a similar scheme for free and complexed ketone to give final products is proposed. 1985, American Chemical Society. All rights reserved.