Diethyl 1-fluoromethylphosphonocarboxylic esters 4, bearing a variety of ester groups (alkyl, aryl), have been conveniently prepared in a one-pot process, by reaction of chloroformates with 1-lithio-1-fluoro-1-(trimethylsilyl) methylphosphonate 2 derived from 1, 1-dibromo-1- fluoromethylphosphonate 1. The overall yields generally range from 80 to 91%. Reaction of 2 with CO2 leads to a novel efficient synthesis of diethyl 1- ...
