(Aminomethyl)phosphonic acid → Glyphosate

Participants

Reaction Steps

Aminomethylphosphonic acid (5.50 g, 0.05 mol) was dissolved in 50 ml of water maintained at 95°-100° C. Glyoxylic acid hydrate (9.70 g, 0.105 mol) was added in one portion. After 8 hours of reaction time, the water was removed on a rotary evaporator to afford a brown semisolid. Trituration of this semisolid with a small amount of water followed by filtration afforded 6.43 grams of glyphosate as a crude white solid. An additional 1.60 grams of glyphosate was recovered by chromatography of the mother liquor as described in Example 22. The total yield of crude product, which was shown by HPLC to contain 98.87 wt % glyphosate, was 8.03 grams. The actual yield of glyphosate was therefore 94.0%.

Provenance & Evidence