Permethrinic acid methyl ester

CLEAR COLOURLESS TO LIGHT YELLOW LIQUID

The preparation methods are as follows. The Farks method (diazoacetate method) is the condensation of isobutylene and chloroacetaldehyde under the catalysis of AlCl3 to form an enol, and then acetylation, zinc powder reduction and acid-catalyzed isomerization to obtain a 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) . In the phase model method, 2-methylbutene [2] alcohol [1] (prenol) and methyl orthoacetate (ethyl ester) are condensed in the presence of an acidic catalyst such as propionic acid, and Clasen rearrangement is carried out to produce 3. 3-Dimethylpentene [4] methyl (ethyl) ester [methyl(ethyl) benylate], 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) ). The Sagami-Curalay method consists of 1, 1, 1-trichloro-2-hydroxy-4-methylpentene [4], which is the enol produced from isobutylene and chloroacetaldehyde in the Farkas method. Benzene sulfonic acid catalyzes isomerization to obtain 1, 1, 1-trichloro-2-hydroxy-4-methylpentene-[3], which is then condensed with trimethyl(ethyl) orthoacetate, and 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 Sagami method, but the raw materials used are different, which avoids the reaction of enol and orthoacetate to produce methyl benzate, and the methyl permethrinate is prepared from methyl benzate 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, and 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 produce ketene, and then react with isobutylene under pressure to produce 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.

Used to produce pyrethroid pesticides

Molecular Weight:223.09
XLogP3:3.6
Hydrogen Bond Acceptor Count:2
Rotatable Bond Count:3
Exact Mass:222.0214350
Monoisotopic Mass:222.0214350
Topological Polar Surface Area:26.3
Heavy Atom Count:13
Complexity:254
Undefined Atom Stereocenter Count:2
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes