Controlled Monohalogenation of Phosphonates, Part II: Preparation of Pure Diethyl α-Monohalogenated Alkylphosphonates

Bogdan Iorga (1) , Frédéric Eymery (1) , Philippe Savignac (1)

1 DCPH - Laboratoire Hétéroéléments et Coordination

The reaction of diethyl alkylphosphonates with chlorotrimethylsilane in the presence of LDA leads to the corresponding diethyl 1-lithio(trimethylsilyl)alkylphosphonates which are cleanly halogenated (X=F, Cl, Br, I) with electrophilic reagents then deprotected to give pure diethyl α-monohalogenoalkylphosphonates. The reaction has been extended by the one pot conversion of triethyl phosphate into diethyl α-monohalogenobutylphosphonates in 85-97% overall yields.

Mots clés: diethyl alkylphosphonates; electrophilic halogenating agents; LDA; triethyl phosphate; diethyl α-monohalogenoalkylphosphonates

Domaines: Chimie organique

Bogdan Iorga, Frédéric Eymery, Philippe Savignac. Controlled Monohalogenation of Phosphonates, Part II: Preparation of Pure Diethyl α-Monohalogenated Alkylphosphonates. Synthesis: Journal of Synthetic Organic Chemistry, 2000, 2000 (4), pp.576-580. ⟨10.1055/s-2000-6375⟩. ⟨hal-03161494⟩