A New Mild Deprotecting Method for O-Benzylsulfonyl Phenols and Alcohols Based on a DTBB-Catalyzed Lithiation

Abstract

A variety of alcohols and phenols, protected as the corresponding benzylsulfonic esters, were efficiently deprotected by selective reductive cleavage of the sulfur-oxygen bond, using an excess of lithium sand and a catalytic amount (5 mol%) of 4,4′-di-tert-butylbiphenyl (DTBB) as electron carrier, in THF at 0° C. This deprotection system was also efficient at -50 °C and was compatible with a wide range of other functional groups.

Key words

benzylsulfonyl - protecting group - alcohols - phenols - reductive deprotection

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