The efficacy of permethrin

Permethrin is a kind of insecticide with moderate toxicity to humans and animals and high toxicity to fish, so what is the effect of permethrin? How is permethrin prepared?

First, the basic introduction of Lianben pyrethrum.

The pure permethrin is white solid, which can dissolve in acetone, chloroform, dichloromethane, ether, toluene and heptane, and its solubility in water is 0.1mg/l.

Pyrethrin is stable to light and stable in acidic medium. It is still stable when stored at room temperature for one year, but decomposes in alkaline medium.

In addition to moderate toxicity to humans and animals and high toxicity to fish, it also has acute toxicity to rats and rabbits, but has no irritation to skin and eyes, no teratogenicity, carcinogenicity and mutagenicity.

Second, the efficacy of permethrin.

Pyrethrum is a synthetic insecticidal and acaricidal agent. Its main effect is to kill insects and mites. It can be used to control cotton red spider, cabbage green worm, cotton bollworm, Hawthorn leaf mite, tea inchworm and other insect pests.

3. The preparation method of permethrin.

1. Put kungfu acid into acyl chlorination kettle, drop it into thionyl chloride for acyl chlorination reaction to form kungfu acyl chloride; then add o-methylbiphenyl methanol, toluene, NaOH solution and water to the condensation kettle, drop kungfu acyl chloride into the reaction kettle, wash it with water, and finally get the finished product after distillation, purification and drying.

2. It was prepared from 3-dimethyl-1-enopentanoic acid-2-methyl-3-phenyl bromobenzyl by condensation, cyclization and dehydrochlorination.

3. 2-phenylbenzoyl chloride was prepared by the reaction of 2-phenylbenzoic acid with SOCl2, and then reacted with dimethylformamide to give the corresponding 2-phenylbenzamide, which was reduced to 2-phenyldimethylbenzylamine by lithium aluminum hydride. The corresponding ammonium salt was prepared by the reaction of 2-phenyldimethylbenzylamine with CH3I, which was isomerized and reacted with ethyl chloroformate to give 2-methyl-3-phenylbenzyl chloride. Finally, bifenthrin was prepared by refluxing with the corresponding acid in acetonitrile for 16 h in the presence of KOH.