A Practical Route for the Preparation of Bis(2,2,2-trifluoroethyl) 2-Oxoalkylphosphonates

Abstract

A generally applicable, practical route was developed for the preparation of bis(2,2,2-trifluoroethyl) 2-oxoalkylphosphonates starting from the corresponding dimethyl 2-oxoalkylphosphonates. The three-step procedure contains mild and easily scaled up transformations such as trimethylsilylation, chlorination with oxalyl chloride, and trifluoroethylation; the overall yield is ca. 50%.

Key words

Horner–Wadsworth–Emmons reaction - phosphorus - Z-enones - ketones - demethylation - halogenation - stereoselectivity

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