METHOD OF OBTAINING DESMEDIPHAM Russian patent published in 2023 - IPC A01N37/22 A01N47/22 C07C231/08 C07C269/02 

FIELD: pesticides production.

SUBSTANCE: invention relates to the field of producing pesticides, in particular to a method of producing desmedipham. The method of producing desmedipham involves the initial interaction of ethanol with triphosgene in the presence of a base in an organic solvent in an inert gas atmosphere or in the air without moisture. As a result of the interaction, ethyl chloroformate is generated in an organic solvent environment. Next, the resulting solution is used in interaction with 3-aminophenol in the presence of a base in an organic solvent or in its mixture with water. As a result of this reaction, ethyl-N-(3-hydroxyphenyl)carbamate is obtained in an organic solvent, which is used in the reaction with phenyl isocyanate to obtain the target product. Next, desmedipham is isolated and purified. The base used is an organic base, which is selected from tertiary amines, pyridines, quinolines or 3-aminophenol, or an inorganic base, which is selected from sodium or potassium hydrogen carbonates or carbonates. Organochlorine hydrocarbons, nitriles or ethers are used as organic solvents. Nitrogen or argon is used as an inert gas.

EFFECT: proposed method of producing desmedipham improves the technical and economic indicators of the technological process for the production of desmedipham by eliminating the use of intermediate ethyl chloroformate and ethyl-N-(3-hydroxyphenyl)carbamate in individual form, increasing its safety with obtaining the target high-quality product with a yield of 80–85%.

4 cl, 5 ex