Monodealkylation of phosphonic esters - Synthesis of phosphonic monosalts and monoacids

This paper describes the synthesis and the characterization by H-1 and P-31 NMR of several monosalts and monoacids issued from phosphonates bearing al kyl groups (CI to CIS) or alkylene groups (allyl or vinyl), Functional comp ounds (alcohol or acetate) were also used and the results demonstrate the r eaction selectivity. The method involves sodium iodide in ketones (acetone or 2-butanone) under reflux. It is very selective for monosalts, but only methyl phosphonates ar e very reactive. The corresponding acids, were then obtained in quantitativ e yields with a cation exchange resin (sulfonic acid).