METHOD OF NICOSULFURON PRODUCTION Russian patent published in 2023 - IPC C07D401/12 A01N41/06 A01N43/40 A01N43/54 

FIELD: pesticides production.

SUBSTANCE: invention relates to a method of nicosulfuron production. The method of nicosulfuron production is performed by reaction of 2-aminosulfonyl-N,N-dimethylnicotinamide with 2-phenoxycarbonylamino-4,6-dimethoxypyrimidine in an aqueous-organic medium being a mixture of water and 10 to 90 vol.% organic component, as a solvent in the presence inorganic base. Next, the resulting reaction mass containing the corresponding nicosulfuron salt is treated with a mineral acid selected from hydrochloric, sulfuric or phosphoric acid, or an organic acid selected from formic, acetic or propionic acid, to obtain the target product, its isolation and purification. As an organic component of the aqueous-organic medium, a water-soluble polar protic organic solvent selected from monohydric alcohols, polyhydric alcohols or cellosolves, or a water-soluble polar aprotic organic solvent selected from ketones, nitriles, cyclic or acyclic ethers, sulfoxides, amides or ureas is used. The inorganic base is an oxide, hydroxide, carbonate, hydrogen carbonate, phosphate or hydrogen phosphate of an alkali metal selected from lithium, sodium, potassium or cesium, or an alkaline earth metal selected from magnesium, calcium, strontium or barium. An inorganic base is added to a solution or suspension of a mixture of 2-aminosulfonyl-N,N-dimethylnicotinamide and 2-phenoxycarbonylamino-4,6-dimethoxypyrimidine in an aqueous-organic medium, or an inorganic base in the form of an aqueous solution or suspension is added to a solution or suspension of a mixture of 2-aminosulfonyl -N,N-dimethylnicotinamide and 2-phenoxycarbonylamino-4,6-dimethoxypyrimidine in an aqueous-organic medium or in an organic component of an aqueous-organic medium.

EFFECT: proposed method of nicosulfuron production improves the technical and economic indicators of the technological process by eliminating the use of organic bases and anhydrous organic solvents, simplifying the process, reducing the total amount of organic substances used, reducing the content of organic components in aqueous-organic production waste, obtaining high quality target product with a yield of 92–99%.

5 cl, 11 ex