Acephate

White Solid Acephate is an organophosphate foliar spray insecticide of moderate persistence with residual systemic activity. It is a contact and systemic insecticide and very effective against a large number of crop pests, such as alfalfa looper, aphids, armyworms, bagworms, bean leafbeetle, bean leafroller, blackgrass bugs, bollworm, budworm, and cabbage looper. Colorless crystalline solid (80% or more pure) or white powder (technical). Has an odor of rotten cabbage or mercaptans

1, the production of acephate phosphorus raw materials are methyl chloride, ammonia, dichloroethane, acetic anhydride, dimethyl sulfate. By amination, acylation, isomerization reaction steps derived. 1. Amination of methyl chloride and the corresponding proportion of dichloroethane from the high-level metering tank were added to the amination of the reactor, open the mixing and freezing brine, when the kettle temperature dropped to 15 ° C, by the high ammonia metering tank Slowly dropping ammonia water in the kettle, the kettle in the temperature control 35-40 ℃, keep 35-40min, drop ammonia after completion, adjust the frozen salt water, so that the kettle temperature dropped to 20-23 ℃. Keep the temperature stirring 30-35min, then add 6L of water, stirring for 2-3min, stop stirring, the material pumped to the ammunition separator standing stratification, 30min, the organic phase into the tank by metering, the organic phase is Amine compound with solvent (O, O-dimethyl phosphoroamidothioate). 2. Acylation (1) acetic anhydride method with solvent amine from the high-level measurement tank into the acylation reactor, open the stirring, and then from the acetic anhydride high metering tank by adding acetic anhydride in the acylation reactor, and then open the frozen brine , So that the kettle temperature dropped to 10 ℃, the concentrated sulfuric acid from the high-level measurement tank slowly drop into the reactor, dropping sulfuric acid, open the air pressure, the jacket in the frozen brine discharge, steam slow Slow heating, so that the kettle temperature rose to 55-60 ℃, for 50min, the reaction is completed, and then the kettle temperature dropped to 10 ℃, by the high ammonia tank drops of chlorine water to neutralize the reaction of acetic acid, and to The pH value of 7-8, in the neutralization process, the temperature should be controlled at 30 ℃ below, after the neutralization, the material pumped to the separator in the static separation, separation of the lower organic phase to the crude acylate storage tank, then pumping (O, O-dimethyl-N-acetylphosphoramidothioate) in a distillation kettle by vacuum distillation (degree of vacuum 86.7 kPa, 70 ° C, 15-20 min). (2) Acetyl chloride method with solvent amine from the high-level measurement tank into the acylation reactor, open stirring, from the acetyl chloride metering tank by adding acetyl chloride. And then slowly the reactor temperature rose to 50 ℃, to maintain the temperature response 2h, the reaction completed, the reaction kettle temperature dropped to 10 ℃, and then by the ammonia high-level measurement tank slowly dropping ammonia to neutralize the reaction of acid, And to pH 7, in the neutralization process, the kettle temperature should be controlled below 30 ℃, and after the end, adding the right amount of water. To dissolve in the process and the formation of ammonium salt, stirring 2-3min, the material pumped to the separator static separation. Separation of the lower organic phase, pumping to the distillation kettle decompression dissolved (vacuum 86.7kPa, 70 ℃, 15-20min), that acyl. Acylation reaction using acetic anhydride or acetyl chloride as acylating agent can achieve better results. 3. Isomerization From the acylate metering tank will quantitative acylate into the isomerization kettle, open stirring, followed by dimethyl sulfate metering tank in proportion to the dimethyl sulfate added isomerization kettle, Slowly heated to 65-70 ℃, to maintain the temperature 2h, the material, that was acephate phosphate crude oil. (98%), 3260kg of caustic soda (30%), 120kg of dimethyl sulphate (98%), and ammonia (18%) were produced in the crude oil of 1t50% concentration. (98%), acetic acid (98%) 295kg, amide (40%) 1700kg, acetic anhydride (69%) 490kg, ammonium sulfide (industrial product) 2200kg and dichloroethane (98%) 250kg. 2, the first isomerization of the first acylation O, O - dimethylthiophosphonamides in a small amount of dimethyl sulfate in the presence of heating isomerization to generate O, S-dimethyl thiophosphamide, and then with acetic anhydride or acetyl chloride role in the generation of acephate. After the first acylation isomerization O, O - dimethylthiophosphonamide in dichloroethane or benzene solvent and acylating agent reaction, commonly used acylating agent acetic acid + zinc chloride, vinegar Anhydride, acetyl chloride, ketene and the like. Acylation reaction to produce O, O-dimethyl-N-acetyl thiophosphamide, and then isomerized to acephate in the presence of a small amount of dimethyl sulfate. Using a new catalyst and a special crystal solvent, can be made of high purity of the original drug, the process is: in the reaction flask by adding methamidophos 200g crude oil, stirring heated to the reaction temperature, the role of the catalyst, dropwise acylating agent Acetic anhydride, and controlling the reaction temperature, adding for a few hours to carry out heat preservation reaction, obtaining crude acephate phosphate crude oil; and neutralizing and extracting organic phase and water phase, and organic phase is purified to obtain acephatecrude oil; Adding solvent A and crystal auxiliaries, slowly stirring and crystallizing, filtering and rinsing to obtain finished products. The finished product can be recovered after the mother liquor is treated. The total product yield is> 78% and the content is more than or equal to 98.0%. 3 to methyl chloride, ammonia, dichloroethane, acetic anhydride, dimethyl sulfate as raw material. Through amination, acylation, isomerization reaction system acephate. Namely amination of dimethyl thiophosphoryl amide, by acylation of the acyl derivative of dimethyl N-acetyl thiophosphamide, and then by isomerization reaction to obtain acephate.

Acephate is a broad-spectrum insecticide. It is effective against rice pests such as planthoppers, leafhoppers, thrips, leaf rollers, armyworms Sanhuamin and Erhuamin, cotton aphids, cotton bollworms, fruit tree pear borer, Peach small borer, vegetable diamondback moth, Spodoptera litura, Pieris rapae, wheat aphid, armyworm, etc. have good control effects. The general use concentration (active ingredient) is 0.05-0.1%, and the dosage per mu is 50-70g. It has a good control effect on various pests of grain, oil, fruit and vegetable crops, such as planthoppers, leafhoppers, rice leafhoppers, diamondback moths, aphids, cotton red spiders, etc.

Molecular Weight:183.17
XLogP3:-0.8
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:4
Rotatable Bond Count:3
Exact Mass:183.01190135
Monoisotopic Mass:183.01190135
Topological Polar Surface Area:80.7
Heavy Atom Count:10
Complexity:172
Undefined Atom Stereocenter Count:1
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes