| abstract |
A process for preparing N-phosphonomethylglycine which comprises contacting in an aqueous medium a glycinate salt, formaldehyde and a trialkylphosphite at a pH above about 9 wherein the molar ratio of glycine equivalents to trialkylphosphite is about 1.5:1 to about 5:1 to produce a reaction mixture comprising N-phosphonomethylglycine dialkylester, and hydrolyzing the dialkylester under neutral, acidic or basic conditions. In one embodiment, a triarylphosphite, alcohol and sodium ethoxide are used to produce the trialkylphosphite, which is used without purification. In another embodiment, a dialkylester is extracted from the reaction mixture prior to hydrolysis. |