A series of mono-ester of alkylphosphonates was synthesized by hydrolysis of corresponding phosphonates. As indicated by our experimental results, both quaternary ammonium halides and sodium iodide served as good catalysts for the hydrolysis reaction. It is possible to find wider application in industry. It was found that the reaction between dibutyl phosphite and Grignard reagent of tert- alkylchloride is a new synthetic method for the preparation of monoester of highly hindered alkylphosphonic acids.

Key words: GRIGNARD REAGENT