Ethyl 3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylate

The preparation methods are as follows. The Farks method (diazoacetate method) is the condensation of isobutylene and chloroacetaldehyde to monoenol under AlCl3 catalysis, and then acetylation, zinc powder reduction and acid-catalyzed isomerization to obtain conjugated diene, namely 1, 1-Dichloro-4-methylpentadiene-[1, 3], and finally react with methyl diazoacetate (ethyl) under the catalysis of copper powder to obtain methyl permethrinate (ethyl) . The 002$S phase model method consists of 2-methylbutene [2] alcohol [1] (prenol) and methyl orthoacetate (ethyl) in the presence of acidic catalysts such as propionic acid to carry out the condensation Clasen rearrangement, Generate 3, 3-dimethylpentene [4] methyl (ethyl) ester [benting acid methyl (ethyl) ester], the latter and carbon tetrachloride in the presence of benzoyl peroxide to adjust the polyaddition to obtain 3, 3-Dimethyl-4, 6, 6, 6-tetrachlorohexene [5] methyl (ethyl) ester, then dehydrochlorination in the presence of sodium methoxide, cyclization to form methyl permethrinate (Ethyl ester). The Sagami-Curalay method is composed of 1, 1, 1-trichloro-2-hydroxy-4-methylpentene [4], which is the enol produced by isobutylene and chloroacetaldehyde in the Farkas method. Benzenesulfonic acid catalyzes the isomerization to obtain 1, 1, 1-trichloro-2-hydroxy-4-methylpentene-[3], which is then condensed with trimethyl(ethyl) orthoacetate, Clasen rearrangement reaction, 3, 3-dimethyl-4, 6, 6-trichlorohexene [4] methyl (ethyl) ester is obtained, and part of dichlorobutyrolactone is also generated during the reaction. 3, 3-Dimethyl-4, 6, 6-trichlorohexene [4] methyl (ethyl) ester in the presence of sodium ethoxide, cyclize to produce methyl (ethyl) permethrinate, and dichlorobutane The lactone can be ring-opened with hydrogen chloride or thionyl chloride in methyl (ethyl) alcohol solution to generate 3, 3-dimethyl-4, 6, 6-trichlorohexene [4] methyl (ethyl) ester, and then Cyclization gives methyl (ethyl) permethrinate. The vinylidene chloride method is similar to the phase model method, but the raw materials used are not the same. It avoids the reaction of enol and orthoacetate to produce methyl betentate. The methyl permethrinate is prepared from methyl betentate and Same as Sagami method. Use isoprene as raw material to react with two molecules of hydrogen chloride to generate 1, 3-dichloro-3-methylbutane, and then react with vinylidene chloride to generate 1, 1, 5-trichloro-3, 3-di Methyl pentene [1], then hydrolyzed with concentrated H2SO4 or alkali to obtain 5-chloro-3, 3-dimethylvaleric acid, which is esterified with methanol in acidic medium to generate the corresponding 5-chloro-3, 3 -Methyl dimethylvalerate, then dehydrochlorination with sodium methoxide to obtain 3, 3-dimethylpentene [4] methyl ester, namely methyl pentene acid. The cyclobutanone method uses acrylonitrile and carbon tetrachloride under pressure to carry out telomerization reaction with Cu as a catalyst to produce 2, 4, 4, 4-tetrachlorobutyronitrile, which is further hydrolyzed and acylated to produce 2, 4 , 4, 4-Tetrachlorobutyryl chloride, and then in the presence of triethylamine, pressurized dehydrochlorination to generate ketene, and then react with isobutylene under pressure to generate 2-chloro-2-trichloroethyl-3, 3-di Methylcyclobutanone, in the presence of triethylamine, Cine rearrangement gives 2-trichloroethyl-3, 3-dimethyl-4-chlorocyclobutanone, and Favorski rearrangement gives 3-trichloro Ethyl-2, 2-dimethylcyclopropane carboxylic acid, then treated with alkali, dehydrochlorination is obtained permethrin acid. In the NRDC method, the Wittig reaction of methyl caruronate and triphenylmethylene phosphine dichloride is carried out to obtain methyl permethrin.

Ethyl permethrin is an important intermediate for pyrethroids, and can be used to prepare permethrin, cypermethrin, lambda cypermethrin, tetrafluthrin, and cyfluthrin.

Molecular Weight:237.12
XLogP3:4
Hydrogen Bond Acceptor Count:2
Rotatable Bond Count:4
Exact Mass:236.0370851
Monoisotopic Mass:236.0370851
Topological Polar Surface Area:26.3
Heavy Atom Count:14
Complexity:267
Undefined Atom Stereocenter Count:2
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes