Rapid syntheses of difluorinated polyols using a cleavable carbamate

Abstract

Trifluoroethyl N-[2-(tert-butyldiphenylsilyloxy)ethyl]-N-isopropylcarbamate undergoes smooth dehydrofluorination–metallation followed by BF₃·OEt₂ mediated addition to aldehydes to afford a range of allylic alcohols; aldol reaction with a second aldehyde, then reduction, affords products which can be deprotected to afford difluorinated polyols.

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