Hydrochloric Acid → Glyphosate

Participants

Reaction Conditions

Reaction Steps

In a 100 ml Monel autoclave were mixed 2.30 g (11.7 mmol) of N-(2-hydroxyethyl)-N-isopropylaminomethylphosphonic acid and 3.73 g (93.0 mmol) of dry, powdered NaOH. The reagents were mixed together well. The reaction vessel was flushed with N2, and the mixture was heated to 315° C. for three hours. During the heating period at 315° C. the internal pressure in the vessel rose from 5×105N/M2 to 1.3×106N/M2. At the end of the heating period the excess pressure that was generated was released and 8 ml of water were introduced. The temperature of the reaction was maintained at 300° C. for three hours while the internal pressure rose from 3.1×106N/M2 to 3.9×106N/M2. The vessel was then cooled to room temperature and the residual pressure was released. The reaction mixture was diluted with water and neutralized with 93 mmol of HCl. This solution was concentrated to dryness. The residue was taken up in conc. HCl and the precipitated NaCl was filtered off. The filtrate was concentrated and purified by ion exchange chromatography (Dowex 50×8-400), to yield 1.03 g (52.0%) of N-phosphonomethylglycine and 0.32 g (13.0%) of N-isopropyl-N-phosphonomethylglycine

Provenance & Evidence