The industrial synthesis of primisulfuron-methyl begins with the preparation of the 4,6-bis(difluoromethoxy)pyrimidine core. This is typically achieved by reacting 2,4,6-trichloropyrimidine with difluoromethanol under basic conditions to substitute chlorine atoms with difluoromethoxy groups. The resulting intermediate is then aminated to introduce the amino group at the 2-position of the pyrimidine ring. Separately, methyl 3-sulfamoylbenzoate is synthesised and reacted with the pyrimidine derivative via a urea linkage using phosgene or a phosgene equivalent. The final product is purified through crystallisation or solvent extraction.
Selective, systemic, absorbed through roots and foliage. Inhibits plant amino acid synthesis - acetohydroxyacid synthase AHAS
