Rapid Chemoselective Deprotection of Benzyl Esters by Nickel Boride

Abstract

Benzyl esters of a variety of acids can be chemoselectively cleaved on treatment with nickel boride in methanol at ambient temperature to give the parent carboxylic acids in high yields. Other protecting functionalities such as methyl, ethyl, tert-butyl, and trityl esters as well as benzyl ethers, tert-butyl ethers, and N-benzylamides are unaffected under these conditions.

Key words

benzyl esters - chemoselectivity - carboxylic acids - cleavage - nickel boride

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