Frédéric Eymery

Controlled monohalogenation of phosphonates: A new route to pure α-monohalogenated diethyl benzylphosphonates

Abstract Starting from diethyl benzylphosphonates, a wide variety of diethyl α-monofluoro, chloro, bromo and iodobenzylphosphonates have been obtained in pure form by a one-pot procedure. This high yielding method implies the intermediate protection of the benzyl anion with TMSCl followed by halogenation with an electrophilic halogenating reagent.

Dialkyl 1-Alkynylphosphonates: a Range of Promising Reagents

This review covers the preparations of 1-alkynylphosphonates by Michaelis–Arbuzov and Michaelis–Becker reactions, by nucleophilic substitutions at phosphorus (SNPV), and by elimination from 1-alkenylphosphonates. The reactivity and versatility of 1-alkynylphosphonates have made them valuable precursors for other phosphonates, and particularly for the synthesis of heterocycles by [2+2], [3+2], and [4+2] cycloaddition reactions.

An efficient synthesis of tetraethyl fluoromethylenediphosphonate and derivatives from diethyl dibromofluoromethylphosphonate

Abstract Treatment of diethyl 1,1-dibromo-1-fluoromethylphosphonate with n -BuLi (1:1) at low temperature affords by self-trapping in quantitative yield the lithiated derivative of tetraethyl fluoromethylenediphosphonate which is reacted with alkylating and halogenating agents or converted with high selectivity into (E) diethyl fluorovinylphosphonates by reaction with carbonyl compounds.

A highly selective synthesis of α-monofluoro- and α-monochloro- benzylphosphonates using electrophilic halogenation of benzylphosphonates carbanions

Abstract The selective electrophilic monofluorination and monochlorination of a wide variety of diethyl benzylphosphonates have been realized in a one-pot procedure. The monohalogenation was accomplished by intermediate of a benzylic carbanion protected with TMSCI using N-fluorobenzenesulfonimide (NFBS) and hexachloroethane, respectively. After mild removal of protecting group, this procedure delivers the α-monohalogenobenzylphosphonates in high yields (68–97%) and pure form.