Process for the preparation of trimethylsulfonium n-phosphonomethylglycine, and process for preparing an aqueous formulation having trimethylsulfonium n-phosphonomethylglycine mixed with ammonium sulfate

摘要

A compound of formula (I) IMAGE (I) where R1, R2, and R3 are alkyl or aralkyl or any two of R1, R2, and R3 together form a cycloalkyl ring and Y is S or S(O) is prepared by reacting N-phosphonomethylglycine with a compound of formula (II) IMAGE (II) where m is 0 or 1 in the presence of a base. A preferred compound of formula (I) is trimethylsulphonium N-phosphonomethylglycine and a preferred compound of formula (II) is trimethylsulphonium hydrogen sulphate.