- Preparation method of cyanogen chrysanthemum ester insecticide
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The invention discloses a preparation method of a Clocythrin pesticide. The method comprises the following steps: a) mixing chrysanthemic acid and chrysanthemyl chloride and placing the mixture into a reaction vessel, adding triethylamine and introducing phosgene, slowly heating to 55-110 DEG C and fully reacting for 1-4 h so as to generate Chrysanthemoyl chloride; and b) dissolving sodium cyanide in an aqueous-phase Triton micellar solution, adding a catalyst and heating to 40 DEG C, slowly and dropwise adding mixed liquor of Chrysanthemoyl chloride and m-Phenoxybenzaldehyde, keeping the temperature and reacting for 1-4 h, cooling to 10 DEG C, adding a few amount of water and crystal seed, fully stirring and precipitating solids, and washing the precipitated solids with alkali, washing, filtering and drying so as to obtain a final product Clocythrin. The solvent in the invention can be recycled, use of the catalyst and water is reduced, and discharge of toxic wastewater and exhaust gas is minimized. The post-processing procedure is simple, and extraction and solvent distillation are not required. The final product can be obtained through simple centrifugation, washing and filtration. Discharge of solid wastes is decreased.
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Paragraph 0023; 0026
(2017/08/25)
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- A new phase transfer catalyst and its applications in organic transformations
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A new quaternary ammonium bromide salt has been used for the first time in phase transfer catalysis (PTC) reactions such as oxidation of alcohols to carbonyl compounds, alkylation and esterification reactions. Improved yields and reduced reaction times have been achieved by this procedure.
- Reddy, Ch. Venkateshwar,Mahesh,Raju,Reddy, V.V. Narayana
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p. 2797 - 2802
(2007/10/03)
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- Method to diagnose metabolic pyrethroid insecticide resistance
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The phenoxybenzyl moiety of conventional pyrethroids is a major site of oxidative metabolism in resistant tobacco budworms, Heliothis virescens (F.). This group was replaced with several P450 monooxygenase-inhibiting or oxidatively blocked groups. Several isomers were tested as insecticides or synergists for insecticides against tobacco budworms that were insecticide-susceptible or that expressed metabolic resistance to cypermethrin. Several compounds with insecticidal and synergistic activities were found. Activity was dependent on both geometric and stereochemical configurations. These compounds may be used in diagnosing the mechanism of resistance in field strains with acquired resistance to pyrethroids. Knowledge of the mechanism underlying acquired insecticide resistance helps farmers to control emerging resistant strains. -GOVT PAR This development of this invention was partially supported by the Government under HATCH finding awarded by the Department of Agriculture to contractor Louisiana State University Agricultural Center. The Government has certain rights in this invention.
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- Fungicidal active compound combinations
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The present application relates to new active compound combinations composed, on the one hand, of prior art compounds metaconazole, 5-[(4-chlorophenyl)methyl]-2,2-dimethyl-1-(1H-1,2,4-triazol-1-yl-methyl)cyclopentanol and imidacloprid, 1-[(6-chloro-3-pyridinyl)-methyl]-4,5-dihydro-N-nitro-1H-imidazole-2-amine, and, on the other hand, of other prior-art active compounds, the combinations being extremely suitable for the protection of wood products.
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- Anti-fouling compositions
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An anti-fouling composition comprising a carrier, and a binder, the improvement which comprises an effective amount of at least one insecticide. The composition is applied to the surfaces of articles which come into contact with seawater or brackish water, especially wood. Other conventional anti-fouling agents may also be present.
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- Para-hydroxyphenylacetic acid for reducing the repellency of insecticides
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The present invention relates to the new use of p-hydroxyphenylacetic acid, by itself or in a mixture with other chemical compounds, for reducing the repellency of insecticides in the control of cockroaches, and to cockroach control compositions which comprise these mixtures, details being found in the description.
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- Methods and agents for combating cockroaches
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The present invention relates to the use of compounds of the general formula I STR1 in which R1 represents C1 -C5 -alkyl or hydroxy-C1 -C5 -alkyl; R2 represents C1 -C5 -alkyl; and m represents an integer from 10 to 20, for combating cockroaches.
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- Conversion of pyrethroid isomers to move active species
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Crystallizable pyrethroid isomers or enantiomer pairs are converted to more pesticidally active isomers by contacting a hydrocarbon slurry of the starting isomers with a base and a catalyst, the catalyst being substantially soluble in the slurry and selected from a quaternary ammonium compound, a quaternary phosphonium compound and a crown ether, agitating the slurry while maintaining a temperature effective for conversion, and recovering the resulting isomers. The tendency to form benzoin ester by-product is reduced by including in the slurry a weak base, an aldehyde scavenger such as a metabisulfite, and/or a tetraalkyl (C1 -C5) ammonium halide catalyst dissolved in an aprotic solvent such as an organic nitrile. The process typically is effective for enriching cypermethrin, cyfluthrin and (cyano (3-phenoxyphenyl)methyl 3-(2,2-dibromoethenyl)-2,2-dimethylcyclopropanecarboxylate in the more active species.
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- Preparation of alpha-cyanobenzyl esters
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A process for the preparation of α-cyanobenzyl esters of cyclopropane carboxylic acids and substituted alkanoic acids by treating a carboxylic acid and a benzaldehyde with a metal cyanide, followed by treatment with a sulfonyl halide.
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- Preparation of cyanobenzyl cyclopropane carboxylates
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A method for preparing a pyrethroid insecticide of general formula: STR1 wherein the two hydrogen atoms on the cyclopropane ring are in the cis- configuration, in which an acid of formula: STR2 is neutralized with a water-soluble base and then reacted in the presence of a phase-transfer catalyst with a solution in a substantially water-immiscible organic solvent of an alpha-cyanobenzyl aryl sulphonate of formula: STR3 the substituents in the formulae having the following meanings; A represents an optionally substituted aryl group; R1 and R2 represent hydrogen or halogen; and R3 and R4 represent chlorine, bromine, or methyl.
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- Production of α-cyanobenzyl esters
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α-Cyanobenzyl esters of the general formula (I) STR1 wherein R1 is an optionally substituted alkyl or cycloalkyl group and R2 is phenoxy, phenylthio or benzyl, are prepared by reacting a benzaldehyde of general formula (II) STR2 an acid halide of the general formula (III) with an excess of a water soluble cyanide in a reaction medium comprising water and a substantially water-immiscible inert organic solvent in the presence of from 20 to 5000 ppm based on the weight of acid halide of formula (III), of a tertiary amine.
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- Novel cyclopropane derivatives
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1-(Dicyano-trimethylsiloxy)methyl-2,2-dimethylcyclopropane derivatives of the formula STR1 wherein R1 is STR2 and X1 is halogen. A process for the production of these compounds and their use as intermediates for obtaining biocidal compounds is described.
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- Preparation of esters
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Certain alpha-cyano esters are prepared by reacting an acyl halide with an aldehyde in a substantially water-immiscible aprotic solvent and an aqueous solution of water-soluble cyanide salt in the presence of an amphoteric surfactant rate-promoting agent.
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- Preparation of esters
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Certain alpha-cyano esters are prepared by reacting an acyl halide with an aldehyde in a substantially water-immiscible aprotic solvent and an aqueous solution of water-soluble cyanide salt in the presence of a rate-promoting agent selected from acid salts of tertiary amines.
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- Preparation of esters
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Certain alpha-cyano esters are prepared by reacting an acyl halide with an aldehyde in a substantially water-immiscible aprotic solvent and an aqueous solution of water-soluble cyanide salt in the presence of an amine or cryptate rate-promoting agent.
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- Preparation of α-cyano-benzyl esters
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A process for the preparation of an insecticidally active compound such as STR1 comprising reacting a benzoyl-phosphonic acid ester of the formula STR2 with an alkali metal cyanide in aqueous acetic acid to produce the new compound STR3 which is reacted with an alkali or alkline earth metal salt of the formula STR4
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- Preparation of esters
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α-cyano esters are prepared by reacting an acyl halide with an aldehyde in a homogeneous mixture of substantially water-miscible aprotic solvent and an aqueous solution of water-soluble cyanide salt.
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- Process for preparation of a crystalline insecticidal pyrethroid enantiomer pair
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A crystalline, optically inactive compound comprising an equimolar mixture of the isomers (S)-(cyano) (3-phenoxyphenyl)methyl (1R,cis)-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylate and (R)-(cyano)-(3-phenoxyphenyl)-methyl (1S,cis)-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylate, its preparation by a cyclic crystallization/equilibration process, and its utility as an insecticide are described and exemplified.
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- Preparation of esters
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Certain alpha-cyano esters are prepared by reacting an acyl halide with an aldehyde in a substantially water-immiscible aprotic solvent and an aqueous solution of water-soluble cyanide salt in the presence of an amphoteric surfactant rate-promoting agent.
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- Preparation of esters
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Certain alpha-cyano esters are prepared by reacting an acyl halide with an aldehyde in a substantially water-immiscible aprotic solvent and an aqueous solution of water-soluble cyanide salt in the presence of a rate-promoting agent selected from acid salts of tertiary amines.
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- Preparation of esters
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Certain alpha-cyano esters are prepared by reacting an acyl halide with an aldehyde in a substantially water-immiscible aprotic solvent and an aqueous solution of water-soluble cyanide salt in the presence of an amine or cryptate rate-promoting agent.
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- Preparation of esters
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Certain carboxylic acid esters also containing a cyano group are prepared by reacting an acid halide, an aldehyde and a water-soluble cyanide in the presence of a water-immiscible aprotic solvent and surface-active agent as catalyst.
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- Preparation of phenoxybenzyl esters
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Phenoxybenzyl esters are prepared by neutralizing an aqueous solution of a carboxylic acid and contacting the neutralized solution with a solution of phenoxybenzyl halide in a water-immiscible base in the presence of a phase transfer catalyst.
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