CAS number：63-25-2
molecular formula：C12H11NO2
molecular weight：201.22
EINECS number：200-555-0

English synonyms

1-naftylesterkyselinymethylkarbaminove;1-naphthalenylmethylcarbamate;1-Naphthol N-methylcarbamate;1-naphtholn-methylcarbamate;1-Naphthyl N-methylcarbamateacid O,O-diethyl ester;1-naphthyl-n-methyl-karbamat;alpha-Naftyl-N-methylkarbamat;alpha-Naphthalenyl methylcarbamate

Related categories

Organochlorine pesticides; analytical standards; pesticides; small molecule inhibitors; feed additives; organic raw materials; azide; azo;
AcaricidesAlphabetic;CA - CGPesticides;CarbamatesMethod Specific;Endocrine Disruptors (Draft)Method Specific;
Pesticides; insecticides (mite) agents; organic nitrogen insecticides; diazo compounds; pesticide residues, veterinary drugs and fertilizers; adjuvants; pesticide intermediates; experimental chemicals; agricultural and veterinary raw materials; raw materials; chemical products; biological reagents ;
.Close...;Amines;Aromatics;Intermediates & Fine Chemicals;Pharmaceuticals

Chemical properties

 The pure product is white crystal, m.p.145℃, relative density 1.232(20℃), vapor pressure 0.666Pa(25℃). Solubility: dimethylformamide>45%, acetone>20%, cyclohexanone>20%, methyl ethyl ketone>15%, chloroform>10%, ethanol>5%, toluene>1%, water 40mg/L (30 ℃). It is relatively stable to light and heat, decomposes quickly when it encounters alkaline substances, and has no corrosive effect on metals. Industrial products are slightly gray or pink, m.p.142℃.

Use

●  A broad-spectrum carbamate insecticide with high efficiency, low toxicity, low residue and long residual effect. It has strong contact killing effect on pests, has stomach poisoning effect, and has slight systemic effect. Used to control cotton bollworm, leaf roller, cotton aphid, bridge builder, thrips and rice leafhopper, rice leaf roller, rice budworm, rice thrips and fruit tree pests, and can also control vegetable garden snails, slugs and other software animal. The usual dose is 2.6-20g/100 m2.

●  Used to control rice planthoppers, leafhoppers, thrips, bean aphids, soybean borers, cotton bollworms, fruit tree pests, forestry pests, etc.

●  Used to control rice planthoppers, leafhoppers, thrips, cotton bollworms, fruit tree pests, forestry pests, pine caterpillars, etc.

●  This product is a carbamate insecticide with contact and stomach poisoning effects, slightly systemic properties, and can control more than 100 kinds of pests in more than 150 kinds of crops. It can be processed into wettable powder or gel suspension to control rice planthopper, rice leafhopper, cotton pink bollworm, soybean borer and fruit tree pests. It has a good control effect on insects resistant to organochlorine and organophosphorus. The dosage is generally 375-750g active ingredient per hectare. This product cannot be mixed with alkaline pesticides. It is highly toxic to bees and should not be used in beekeeping areas during the flowering season.

●  Used as an insecticide. Calibration of instruments and devices; evaluation methods; working standards; quality assurance/quality control; other.

Production method

●  There are two main processes: cold method (menaphthyl chloroformate method) and thermal method (methacarbamoyl chloride method). 1. Cold method: react methylnaphthol with phosgene to generate methylnaphthyl chloroformate, then react with methylamine to obtain carbaryl. Raw material consumption quota: methylnaphthol (94%) 1100kg/t, monomethylamine (40%) 500kg/t, phosgene 900kg/t. 2. Thermal method: first react monomethylamine with gas to form carbamoyl chloride, and then synthesize carbaryl chloride with methylnaphthol.

●  Isocyanate method
Preparation of methyl isocyanate Methylamine and phosgene are directly subjected to gas chromatography at high temperature, and the reactor is a pipeline. The reaction temperature is greater than 400°C, and the material of the reactor is steel-lined graphite. Preventing the generation of by-products and eliminating reactor clogging are the key points in production.
The main equipment of the methyl isocyanate separation and refining system is the dephosphorization tower, and the refining methyl isocyanate tower is a float valve tower with 90 trays, all of which are made of high-nickel alloy steel.
Synthesis of Carbaryl The reaction is carried out in the presence of a solvent at a temperature of 60-80°C with a slight negative pressure. The resulting mixed solution is distilled, and the excess methyl isocyanate is distilled out from the top of the distillation tower together with part of the solvent, and then reused. Carbaryl is refined in solution to obtain pure product.
Chloroformate method
Preparation of naphthyl chloroformate Dissolve 100kg of methylnaphthol and 200kg of toluene, pump it into a reactor containing 600kg of toluene, stir, cool down to below -10°C, stop stirring, and pass in about 224kg of phosgene for 4 hours. Start adding alkali dropwise, keep the temperature below 0°C, finish dripping 400-500kg of 20% alkali solution in about 2 hours, make the pH of the brine layer = 6, drain the salt water, and wash menaphthyl chloroformate twice with water. The general ester content is 14% ~ 15%.
Synthesis of carbaryl The synthesis temperature is kept at 10-20°C, and about 80kg of 40% monomethylamine is added dropwise at about 40 minutes, and then at about 10°C, 120kg of 20% liquid caustic soda is added dropwise within about 20 minutes, stirred for 10 minutes, and dropped into 30 % hydrochloric acid 80kg, measured pH value is 5～6. After separation, washing and drying, the product is obtained.
Carbamoyl chloride method
Preparation of methylcarbamoyl chloride Methylcarbamoyl chloride was synthesized by chloroformylation of methylamine. Commonly used in industry are liquid phase method and gas phase method, among which the gas phase method has a higher yield and is convenient for continuous operation. The gas phase method is to heat methylamine to above 200°C and phosgene to above 150°C. After the two gases are mixed, they pass through a pipeline reactor at 240-300°C. Or carbon tetrachloride cycle absorption. The main process conditions are: the ratio of monomethylamine to phosgene is 1:1.3 (volume ratio), the preheating temperature of methylamine and phosgene is 220-240°C, the reaction temperature is 280-300°C, and the absorption temperature is 0-20°C .
The synthesis of carbaryl is to prepare sodium naphthol with dilute lye, add methylcarbamoyl chloride dropwise when the temperature reaches 0-5°C, add lye continuously during the dropping process, and wait until the pH value reaches 7.5 When the temperature reaches 8.0, the reaction reaches the end, and the reaction time takes about 30-40 minutes. Centrifuge, wash, and dry to get the finished product, with a content of more than 90%.
Carbaryl can also be synthesized by solvent method or solvent-free method.

Team Presentation