Preparation of n-phosphonomethyl glycine

A process for the production of N-phosphonomethyl glycine which comprises (a) reacting a 1,3,5-tricarbohydrocarbonoxy-methyl-hexahydrotriazine of the formula ##STR2## wherein R is a monovalent hydrocarbon or substituted hydrocarbon radical in which the substituent is inert to the reaction;

• with a phosphite ester of the formula ##STR3## wherein the R' is the same or different radical as defined for R, in the absence of a catalyst, by heating a mixture of said triazine and said ester to a temperature sufficiently elevated to initiate and maintain the reaction to form a triester of N-phosphonomethyl glycine of the formula ##STR4## wherein R and R' are as above defined, (b) hydrolyzing the triester and (c) recovering N-phosphonomethyl glycine.