Preparation method of chlorfenapyr

Abstract

The invention relates to a preparation method of chlorfenapyr, wherein, 4-bromine-2-(4-chlorphenyl)-5-trifluoromethyl pyrrole-3-nitrile and chloromethyl ethers are taken as raw material, alkali carbonate or organic amine is taken as acid-binding agents, and esters are taken as reaction solvent so as to prepare chlorfenapyr. The preparation method adopts ester solvent, reduces the treatment difficulty of waste water in the later period, lowers the manufacturing cost greatly, and reduces the environmental protection treatment pressure; the manufacturing cost is 20 percent lower than the diethoxymethane technology and is 10 percent lower than the ketones solvent technology; the wastewater quantity is only about 10 percent of the diethoxymethane technology and is about 25 percent of the ketones solvent technology; and unforeseen benefits can be achieved by compared with the traditional ketones solvent.

Description

technical field [0001] The invention relates to a method for preparing chlorfenapyr, in particular to a method for preparing chlorfenapyr in the presence of an ester solvent and an acid-binding agent. Background technique [0002] Chlorfenapyr, the English name is Chlorfenapyr, the trade name is divided, and the Chinese common name is Chlorfenapyr. The chemical name is 4-bromo-2-(4-chlorophenyl)-1-(ethoxymethyl)-5-(trifluoromethyl)pyrrole-3-carbonitrile, and the chemical structure is: [0003] [0004] Chlorfenapyr is a new type of heterocyclic insecticide, acaricide and nematicide successfully developed by American Cyanamid Company. It has high activity and long-lasting effect. It is safe for crops and has special effects in controlling diamondback moth. The drug is a new type of pyrrole compound, which acts on the mitochondria of cells in the insect body, acts through the multifunctional oxidase in the insect body, and mainly inhibits the conversion of adenosine diphos...

AI Technical Summary

Problems solved by technology

Such as Journal of Organic Chemistry, 49 (1) p.203 (1984), US 5151536 introduction is acid-binding agent with sodium hydrogen; US5010098 then is acid-binding agent with tertiary J alkoxide sodium; Certainly dangerous, the solvent tetrahydrofuran used is also relatively expensive, and the recovery rate is not high

US535909 adopts the diethoxymethane process, using triethylamine as the acid-binding agent and toluene as the solvent, which solves the aforementioned problems preferably. It is a commonly used production method at present. Its disadvantage is that diethoxymethane is more expensive. Moreover, a liquid catalyst needs to be added during the reaction process, resulting in a large amount of waste water in the post-treatment process, and the recovery cost of the acid-binding agent triethylamine is relatively high

At the same time, the invention patent with the Chinese patent application number CN200910043790.0 discloses "the preparation method of chlorfenapyr and its analogues", and proposes "preparing chlorfenapyr in the presence of ketone solvents and inorganic alkali acid-binding agents", but, Due to the good miscibility between ketone solvents and water, a large amount of solvents enter the water phase, which increases the difficulty of wastewater treatment in the later stage. At the same time, the recovered solvent contains a large amount of water, which must be re-used after distillation, dehydration, rectification and other post-treatment processes; and Low-carbon ketones (3 to 4 carbon atoms) are highly volatile and have high losses during production

These factors lead to the high production cost of the production process using ketone solvents, and the pressure of environmental protection treatment is high

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