FIELD: pesticide production.
SUBSTANCE: invention relates to the field of pesticide production, more specifically to a method for producing triflusulfuron-methyl (methyl 2-[4-dimethylamino-6-(2,2,2-trifluoroethoxy)-1,3,5-triazin-2-ylaminocarbonylaminosulfonyl]-3-methyl benzoate),
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which is a systemic postemergence herbicide from the sulfonylurea class. The method for obtaining the herbicide triflusulfuron-methyl includes the interaction of methyl 2-(chlorosulfonyl)-3-methylbenzoate, sodium cyanate, pyridine and 2-amino-4-dimethylamino-6-(2,2,2-trifluoroethoxy)triazine-1,3,5 in acetonitrile as a solvent, followed by its isolation after the reaction and purification, which is carried out by keeping the obtained triflusulfuron-methyl in a mixture of water and lower alcohol in the presence of an inorganic acid at a temperature of 10-30°C for 1-3 hours. The concentration of lower alcohol in a mixture with water is from 10 to 90 vol. %, and methanol, ethanol, propanol or isopropanol are used as the lower alcohol. The inorganic acid used is hydrochloric, sulfuric or phosphoric acid.
EFFECT: proposed method for producing the herbicide triflusulfuron-methyl provides a simplification of the stage of purification of TFSM during its production, reduction of its duration due to a significant reduction in the number of required technological operations and, as a consequence, an increase in the technical and economic indicators of the process as a whole; mitigation of industrial and fire safety requirements during its implementation by eliminating the use of a dangerous solution of sodium methoxide in methanol; obtaining at this stage purified TFSM with a yield of up to 92% and a quantitative content of up to 98.8%.
4 cl, 6 ex
