Convenient Formation of Diphenylmethyl Esters Using Diphenylmethyl Trichloroacetimidate

Abstract

Diphenylmethyl trichloroacetimidate is a useful reagent for the protection of carboxylic acids as their corresponding diphenylmethyl esters. These esterifications proceed rapidly without the need for an added catalyst or promoter. A variety of carboxylic acid substrates undergo esterification in excellent yields with the trichloroacetimidate reagent, including substrates possessing acid- or base-sensitive functionality. Protection of a carboxylic acid with a highly enolizable α-stereocenter using diphenylmethyl imidate was also accomplished without racemization.

Key words

esters - protecting groups - C–O bond formation - chemoselectivity - esterification

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