Low-temperature synthesis process of clomazone

A technology of clomazone and synthesis process, applied in the field of low-temperature synthesis technology of clomazone, can solve the problems of complex synthesis process of clomazone, unreasonable allocation of resources, low yield of clomazone, etc. Ease of separation, reduced side reactions, and improved selectivity

CN110172042APending Publication Date: 2019-08-27JIANGSU HEBEN BIOCHEM +1
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Patent Information

Authority / Receiving Office
CN · China
Current Assignee / Owner
Publication Date
2019-08-27

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Abstract

The invention discloses a low-temperature synthesis process of clomazone. The low-temperature synthesis process of the clomazone comprises condensation reaction, cyclization reaction, synthesis reaction and configuration conversion. The low-temperature synthesis process of the clomazone disclosed in the invention starts from analyzing side reaction products, determines the chemical composition ofimpurities, and reduces the amount of the impurities by optimizing process parameters, finding high-efficiency catalysts and controlling side reactions; then, through chemical treatment on the produced isomers, part of the isomers are converted into the product, and part of irreversible by-products are converted into high-boiling-point polymer compounds through reaction, so that the clomazone product is easy to separate; finally, the clomazone product is purified through physical methods to obtain the clomazone with a purity greater than 97%.
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Description

technical field

[0001] The invention relates to the technical field of pesticide technical synthesis process, in particular to a low-temperature synthesis process of clomazone. Background technique

[0002] The structural formula of clomazone is , is a colorless transparent to light brown viscous liquid, melting point 25°C, boiling point 275.4°C, density 1.129 (20°C), vapor pressure 19.2MPa (25°C), solubility in water 1.1g / l (25°C), compatible with acetone , Acetonitrile, Chloroform, Cyclohexanone, Dichloromethane, Methanol, Toluene, etc. It can be stored at room temperature for at least 2 years, and can be stored at 50°C for 3 months. It is used for the control of grass and broad-leaved weeds in leguminous crops.

[0003] Clomazone is a low-toxicity herbicide, and the oral LD50 of the original drug in rats is 2077 mg / kg (male) and 1369 mg / kg (male). Rabbit acute percutaneous LD50>2000 mg / kg, rat acute inhalation LC50 is 4.85 mg / L. Irritating to eyes, slightly irrita...

Examples

Embodiment 1

[0039] A kind of low-temperature synthesis process of clomazone

[0040] The process steps are as follows:

[0041] Step 1, condensation reaction: add 1120kg of process water, 307kg of hydroxylamine hydrochloride into the reactor, and start stirring, then pump 670kg of chloropivaloyl chloride into No. 1 enamel metering tank, and pump 2290kg of mass fraction into No. 2 metering tank 30% liquid caustic soda, when the temperature in the reactor drops to 0°C, start to drop chloropivaloyl chloride and 30% liquid caustic soda at the same time, control the temperature in the reactor to 0°C, and control the pH to 6.95, after the dropwise addition of chlorpivaloyl chloride, the pH value is 7.41, stop the dropwise addition of liquid caustic soda with a mass fraction of 30%, then add 650kg of 1,1-dichloroethane to dissolve, and then transfer the reactant to the ring-closure kettle;

[0042] Wherein, chloropivaloyl chloride was added dropwise within 1.5 hours.

[0043] Step 2, cyclizati...

Embodiment 2

[0051] A kind of low-temperature synthesis process of clomazone

[0052] The process steps are as follows:

[0053] Step 1, condensation reaction: add 1180kg of process water, 308kg of hydroxylamine hydrochloride into the reactor, and start stirring, then pump 680kg of chloropivaloyl chloride into No. 1 enamel metering tank, and pump 2310kg of mass fraction into No. 2 metering tank 30% liquid caustic soda, when the temperature in the reactor drops to 10°C, start to drop chloropivaloyl chloride and 30% liquid caustic soda at the same time, control the temperature in the reactor to 15°C, and control the pH value to 7.10, after the dropwise addition of chlorpivaloyl chloride, the pH value is 7.52, stop the dropwise addition of liquid caustic soda with a mass fraction of 30%, then add 660kg of 1,1-dichloroethane to dissolve, and then transfer the reactant to the ring-closure kettle;

[0054] Wherein, chloropivaloyl chloride was added dropwise within 2.5 hours.

[0055] Step 2, c...

Embodiment 3

[0063] A kind of low-temperature synthesis process of clomazone

[0064] The process steps are as follows:

[0065] Step 1, condensation reaction: add 1140kg of process water, 307.74kg of hydroxylamine hydrochloride into the reactor, and start stirring, then pump 672.29kg of chloropivaloyl chloride into No. 1 enamel metering tank, and pump 2301.3 kg into No. kg mass fraction is 30% liquid caustic soda, when the temperature in the reactor drops to 3 ℃, start to drop chlorpivaloyl chloride and mass fraction simultaneously and be 30% liquid caustic soda, the temperature control in the reactor is 5 ℃, control The pH value is 6.99. After the chloropivaloyl chloride has been added dropwise, the pH value is 7.49. Stop adding the liquid caustic soda with a mass fraction of 30%. close together

[0066] Wherein, chloropivaloyl chloride was added dropwise within 2.0 hours.

[0067] Step 2, cyclization reaction: raise the temperature of the cyclization kettle to 42°C, and start adding ...