Method for producing chlorfenapyr raw material pesticide

Abstract

The invention discloses a method for producing a chlorfenapyr raw material pesticide. The method comprises the following steps of: adding chlorobenzol glycine and trifluoroacetic acid which serve as raw materials and 4-dimethylamino pyridine serving as a catalyst into an acetonitrile solvent, stirring uniformly, and dripping a phosphorus trichloride solution to perform acylation reaction; after the reaction is finished, adding 2-chloro acrylonitrile serving as a raw material and dimethyl formamide (DMF) serving as a cosolvent, and stirring for dissolving; dripping a triethylamine solution to perform cyclization reaction, and dripping bromine into the reaction solution; after bromination reaction is finished, and removing the solvent and the cosolvent; adding the residual substance into an alcohol solvent for dissolving, and cooling to precipitate an intermediate; adding the intermediate and chloromethyl ethyl ether into ethyl acetate serving as a solvent, stirring for dissolving, dripping triethylamine to perform condensation reaction, removing the solvent and the ethyl acetate, and hydrolyzing to obtain the chlorfenapyr raw material pesticide. In the method, the acylation reaction and the cyclization reaction are completed in one step, so a process is simplified, energy consumption is reduced, a production process is energy-saving and environment-friendly, and the purity and yield of products are improved.

Description

technical field [0001] The invention relates to the technical field of pesticides, in particular to a production method of chlorfenapyr as a technical compound. Background technique [0002] Chlorfenapyr (proPiconazole), the English name Chlorfenapyr, is a new type of heterocyclic insecticide, acaricide and nematocide drug successfully developed by American Cyanoamide Company. The chemical name of chlorfenapyr is: 4-bromo-2- (4-Chlorophenyl)-1-ethoxymethyl-5-trifluoromethylpyrrole-3-carbonitrile, molecular formula: C 15 h 11 BrClF 3 N 2 O, molecular weight: 407.62, pure product is white or off-white crystal powder, melting point: 100-101°C, easily soluble in organic solvents such as acetone, ether, dimethyl sulfoxide, tetrahydrofuran, acetonitrile, alcohol, toluene, xylene, etc. in water. pH: 6~8, acute toxicity in rats (oral administration) LD50 441~1152mg / Kg, acute transdermal dose in rabbits LD50 ≧2000 mg / Kg, slight eye irritation in rabbits. Chlorfenapyr is an inse...

AI Technical Summary

Problems solved by technology

[0004] This technique has the following major problems: after the acylation reaction, the cyclization reaction and the bromination reaction, it is necessary to remove the solvent and add a new solvent after washing to carry out the next step reaction. low; and in 2-(4-chlorophenyl)-5-trifluoromethylpyrrole-3-carbonitrile and 4-bromo-2-(4-chlorophenyl)-5-trifluoromethylpyrrole-3- A large amount of waste water is produced during the treatment of nitrile and crude products. Waste water treatment is very difficult, and the condensation reaction is carried out directly after bromination. There are many side reactions in the condensation reaction process. The quality of the crude product of chlorfenapyr is poor, which affects the quality of the finished product, resulting in low product content , higher production cost