Carboxylic esterification with benzyl bromide

Benzyl and p-nitrobenzyl esters are usually made by classical methods such as reaction of benzyl alcohol with an acid chloride in the presence of pyridine or with a carboxylic acid in the presence of a carbodiimide (see general esterification methods). We have already shown the conversion of the cesium salt of a carboxylic acid to its benzyl ester by reaction with benzyl bromide [Scheme 6.40] ... 

There have been a number of reagents employed for the esterification of carboxylic acids. 2-Naphthacyl bromide has been used for the esterification of fatty acids and barbiturates (33), the absorption provided by the naphthalene ring giving sensitivity levels of detection of about 4 x 10 g/ml. The benzyl esters of fatty acids have been prepared with the use of l-benzyl-3-p-tolytriazine (34) and the p-methoxyanilides of fatty acids prepared by means of triphenylphosphine (35). The... 

In studies directed towards the synthesis of pseurotin A, the unsaturated acetal 3 has been used as a common starting material to prepare two different C-2-branched intermediates. In one route, 3 was 0-benzylated, the aldehyde im-masked with hydrochloric acid and oxidized to its carboxylic acid derivative. Esterification, dihydroxylation of the alkene then dimethylsulfoxide-thionyl chloride oxidation, addition of ethylmagnesium chloride and removal of the isopropylidene group gave compounds 4. In an alternative route, 3 was first epoxidized then treated sequentially with hydroxide, benzyl bromide-base and hydrochloric acid to give compounds 5. ... 

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