CN109354590B - Synthesis method of thiacloprid - Google Patents
Synthesis method of thiacloprid Download PDFInfo
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- CN109354590B CN109354590B CN201811546395.XA CN201811546395A CN109354590B CN 109354590 B CN109354590 B CN 109354590B CN 201811546395 A CN201811546395 A CN 201811546395A CN 109354590 B CN109354590 B CN 109354590B
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- C07—ORGANIC CHEMISTRY
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- C07D417/00—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and sulfur atoms as the only ring hetero atoms, not provided for by group C07D415/00
- C07D417/02—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and sulfur atoms as the only ring hetero atoms, not provided for by group C07D415/00 containing two hetero rings
- C07D417/06—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and sulfur atoms as the only ring hetero atoms, not provided for by group C07D415/00 containing two hetero rings linked by a carbon chain containing only aliphatic carbon atoms
Abstract
The invention discloses a thiacloprid synthesis method, which comprises the steps of mixing raw materials of 2-cyanoimino-1, 3-thiazolidine and 2-chloro-5-chloromethylpyridine in a solvent, reacting under the condition of guanidine organic alkali, and then adopting different post-treatment methods according to different solvents; and because guanidine hydrochloride is easily dissolved in water and organic solvent, the post-treatment is simple, and the high-purity thiacloprid product with the content of more than 97 percent can be obtained only by adding a small amount of water (and alcohol), so that the method is suitable for large-scale industrial production; by adopting the synthesis method of thiacloprid, the product yield can reach more than 92 percent; guanidine in the wastewater can be further recovered after the organic solvent is recovered, so that the production cost is reduced, and only a small amount of brine is finally generated, thereby meeting the requirements of environment-friendly production.
Description
Technical Field
The invention relates to the technical field of synthesis of nicotine pesticide, in particular to a synthesis method of thiacloprid.
Background
Thiacloprid is a novel chloronicotinyl insecticide, is developed by cooperation of Germany Bayer agriculture and chemical companies and Japan Bayer agriculture and chemical companies, and is mainly used for acting on insect nerve bound membranes, and is bound with a saline-alkali acetylcholine receptor to interfere normal conduction of insect nervous systems, so that nerve channel blockage is caused, a large amount of acetylcholine is accumulated, and insects are excited abnormally and die due to systemic spasm and paralysis. In addition, thiacloprid has stronger functions of systemic absorption, contact killing and stomach toxicity, has no cross resistance with conventional insecticides such as pyrethroids, organophosphorus and carbamates, and can be used for resistance treatment; and thiacloprid is one of two nicotine insecticides which are not forbidden in Europe and America, and can certainly cause wider application under the condition that no other large insecticides appear, thereby having wider application prospect.
Although the production technology of thiacloprid is mature, two problems still exist: firstly, the product yield is relatively low, the production cost is high, and the market competitiveness is reduced; secondly, the waste water is more, which brings pressure to environmental protection; in Chinese patent CN1161354C (Bayer corporation), n-butanol is used as a solvent to react at 50-80 ℃, and alkali such as potassium carbonate, sodium hydroxide and the like is used as an acid-binding agent to react, so that the product yield reaches 87 percent to the maximum; in India patent 2003MU00019, DMF is used as a solvent, potassium hydroxide is used as an acid-binding agent, and the reaction is carried out at 40 ℃ for 6 hours, so that the product yield only reaches 70%; in international patent WO2013030152, tert-butyl alcohol is used as a solvent, potassium carbonate is used as an acid-binding agent, and the product yield reaches 80%; in Chinese patent CN107629045, water is used as a solvent, potassium carbonate is used as an acid-binding agent for reaction, and the product yield is 88%; chinese patent CN102399216 also describes a method for producing thiacloprid technical, in which methanol is used as solvent, and formaldehyde is added as catalyst, and finally it causes great pollution and waste, so it is not suitable for practical production. The international patent WO2017048628 applied in 2017 by the agricultural and chemical Jutou Bayer company adopts a toluene-water two-phase method, sodium carbonate is used as an acid-binding agent, and the product yield is only 88%.
Disclosure of Invention
In order to solve the problems of low yield and more difficult wastewater treatment in thiacloprid production, the invention aims to provide a method for synthesizing thiacloprid.
In order to achieve the purpose, the invention is realized by the following technical scheme:
a synthetic method of thiacloprid comprises the following steps:
① adding 2-cyanoimino-1, 3-thiazolidine, a solvent and an organic base into a reaction kettle, cooling to 0-30 ℃, keeping the temperature, adding 2-chloro-5-chloromethylpyridine into the reaction kettle, stirring and reacting at 20-50 ℃ for 5-15 hours after the addition is finished, adding hydrochloric acid into the reaction kettle, and adjusting the pH of a reaction solution to 1-6 to obtain a mixed solution;
the organic base is N, N-dimethylguanidine or tetramethylguanidine; the solvent is an alcohol solvent or chlorinated hydrocarbon; wherein the molar mass ratio of the 2-cyanoimino-1, 3-thiazolidine, the solvent, the organic base and the 2-chloro-5-chloromethylpyridine is 1.0-1.05 mol: 300-500 g: 1.0-1.1 mol: 1.0 mol;
② the mixed solution of step ① is post-treated according to the difference of the solvent:
when the solvent is an alcohol solvent, adding water into the reaction kettle for recrystallization, performing suction filtration, and drying a filter cake to obtain thiacloprid; wherein the mass ratio of water to the alcohol solvent is 1-4: 1;
and when the solvent is chlorohydrocarbon, carrying out reduced pressure distillation on the mixed solution to remove the solvent, then adding the alcohol-water mixed solution into the reaction kettle for recrystallization, carrying out suction filtration, and drying a filter cake to obtain thiacloprid.
Preferably, the organic base is tetramethylguanidine.
Preferably, the alcohol-water mixed solution is n-butyl alcohol aqueous solution or methanol aqueous solution, and the mass percentage concentration of the alcohol-water mixed solution is 20-50%.
Preferably, hydrochloric acid is added into the reaction kettle, and then the pH of the reaction solution is adjusted to 3-4.
Preferably, the molar mass ratio of the 2-cyanoimino-1, 3-thiazolidine to the solvent to the 2-chloro-5-chloromethylpyridine is 1.0-1.02 mol: 350-450 g: 1.0-1.05 mol: 1.0 mol.
Preferably, the alcoholic solvent is butanol.
Preferably, the chlorinated hydrocarbon is dichloromethane or chloroform.
Compared with the prior art, the invention has the following advantages:
according to the method for synthesizing thiacloprid, guanidine is used as an acid-binding agent, the reaction temperature is moderate, and compared with the existing high-temperature process, the energy consumption is saved; and because guanidine hydrochloride is easily dissolved in water and organic solvent, the post-treatment is simple, and the high-purity thiacloprid product with the content of more than 97 percent can be obtained only by adding a small amount of water (and alcohol), so that the method is suitable for large-scale industrial production; by adopting the synthesis method of thiacloprid, the product yield can reach more than 92 percent, and the yield of the preferred scheme is more than 95 percent and is far higher than the product yield of thiacloprid in the prior art; by adopting the method for synthesizing thiacloprid, only 2-3 tons of wastewater is generated when one ton of thiacloprid is produced, and 4-5 tons of wastewater is generated when one ton of thiacloprid is produced by adopting the n-butyl alcohol-potassium carbonate method at present, so that the amount of the generated wastewater is greatly reduced; and guanidine in the wastewater can be further recovered after the organic solvent is recovered, so that the production cost is reduced, and only a small amount of brine is finally generated, thereby meeting the requirements of environment-friendly production.
Detailed Description
The invention is further described with reference to specific examples.
The reaction route for synthesizing thiacloprid of the invention is as follows:
wherein, the time for adjusting the pH by adding hydrochloric acid can also be adjusted by controlling the content of the 2-chloro-5-chloromethylpyridine in the liquid phase during the reaction, and the pH can be adjusted by adding hydrochloric acid when the content of the 2-chloro-5-chloromethylpyridine in the liquid phase is controlled to be less than or equal to 1 percent (area normalization method), so that the conversion rate of the raw material 2-chloro-5-chloromethylpyridine can be controlled to be more than 99 percent.
Example 1
A synthetic method of thiacloprid comprises the following steps: adding 127.1kg of 2-cyanoimino-1, 3-thiazolidine, 300kg of methanol and 87.1kg of N, N-dimethylguanidine into a reaction kettle, cooling to 0-5 ℃, keeping the temperature, adding 162.0g of 2-chloro-5-chloromethylpyridine into the reaction kettle, stirring and reacting for 5 hours at 20-25 ℃ after the addition is finished, adding hydrochloric acid into the reaction kettle, adjusting the pH of a reaction solution to 1, adding 400kg of water into the reaction kettle, recrystallizing, performing suction filtration, and drying a filter cake to obtain 234.0kg of thiacloprid, wherein the yield is 92.6%, and the content is 97.7%.
Example 2
A synthetic method of thiacloprid comprises the following steps: adding 133.45kg of 2-cyanoimino-1, 3-thiazolidine, 500kg of ethanol and 126.7kg of tetramethylguanidine into a reaction kettle, cooling to 10-15 ℃, keeping the temperature, adding 162.0kg of 2-chloro-5-chloromethylpyridine into the reaction kettle, stirring and reacting for 15 hours at 35-40 ℃ after the addition is finished, adding hydrochloric acid into the reaction kettle, adjusting the pH of a reaction solution to 4, recovering a solvent, adding 1500kg of water into the reaction kettle, recrystallizing, performing suction filtration, and drying a filter cake to obtain 233.7kg of thiacloprid, wherein the yield is 92.5%, and the content is 97.5%.
Example 3
A synthetic method of thiacloprid comprises the following steps: adding 132.2kg of 2-cyanoimino-1, 3-thiazolidine, 400kg of propanol and 92.3kg of N, N-dimethylguanidine into a reaction kettle, cooling to 25-30 ℃, keeping the temperature, adding 162.0kg of 2-chloro-5-chloromethylpyridine into the reaction kettle, stirring and reacting for 8 hours at 45-50 ℃ after the addition is finished, adding hydrochloric acid into the reaction kettle, adjusting the pH of a reaction solution to 6, recovering a solvent, adding 800kg of water into the reaction kettle, recrystallizing, performing suction filtration, and drying a filter cake to obtain 234.5kg of thiacloprid, wherein the yield is 92.8%, and the content is 97.3%.
Example 4
A synthetic method of thiacloprid comprises the following steps: adding 127.2kg of 2-cyanoimino-1, 3-thiazolidine, 350kg of butanol and 115.2kg of tetramethylguanidine into a reaction kettle, cooling to 0-5 ℃, keeping the temperature, adding 162.0kg of 2-chloro-5-chloromethylpyridine into the reaction kettle, stirring and reacting for 15 hours at 20 ℃ after the addition is finished, adding hydrochloric acid into the reaction kettle, adjusting the pH of a reaction solution to 1, adding 1400kg of water into the reaction kettle, recrystallizing, filtering, and drying a filter cake to obtain 240.1kg of thiacloprid, wherein the yield is 95.0%, and the content is 98.4%.
Example 5
A synthetic method of thiacloprid comprises the following steps: adding 127.2kg of 2-cyanoimino-1, 3-thiazolidine, 400kg of butanol and 115.2kg of tetramethylguanidine into a reaction kettle, cooling to 0-5 ℃, keeping the temperature, adding 162.0kg of 2-chloro-5-chloromethylpyridine into the reaction kettle, stirring and reacting at 30 ℃ for 8 hours after the addition is finished, adding hydrochloric acid into the reaction kettle, adjusting the pH of a reaction solution to 3, adding 400kg of water into the reaction kettle, recrystallizing, filtering, and drying a filter cake to obtain 246.1kg of thiacloprid, wherein the yield is 97.4%, and the content is 97.5%.
Example 6
A synthetic method of thiacloprid comprises the following steps: adding 127.2kg of 2-cyanoimino-1, 3-thiazolidine, 420kg of butanol and 115.2kg of tetramethylguanidine into a reaction kettle, cooling to 0-5 ℃, keeping the temperature, adding 162.0kg of 2-chloro-5-chloromethylpyridine into the reaction kettle, stirring and reacting at 38 ℃ for 12 hours after the addition is finished, adding hydrochloric acid into the reaction kettle, adjusting the pH of a reaction solution to 5, adding 840kg of water into the reaction kettle, recrystallizing, filtering, and drying a filter cake to obtain 243.8kg of thiacloprid, wherein the yield is 96.4%, and the content is 98.1%.
Example 7
A synthetic method of thiacloprid comprises the following steps: adding 129.7kg of 2-cyanoimino-1, 3-thiazolidine, 450kg of dichloromethane and 120.96kg of tetramethylguanidine into a reaction kettle, cooling to 10-15 ℃, keeping the temperature, adding 162.0kg of 2-chloro-5-chloromethylpyridine into the reaction kettle, stirring and reacting at 30 ℃ for 15 hours after the addition is finished, adding hydrochloric acid into the reaction kettle, adjusting the pH of a reaction solution to 6, recovering a solvent, adding 450kg of an n-butanol water mixed solution with the mass percentage concentration of 50% into the reaction kettle, recrystallizing, filtering, and drying a filter cake to obtain 244.3kg of thiacloprid, wherein the yield is 96.6%, and the content is 98.2%.
Example 8
A synthetic method of thiacloprid comprises the following steps: adding 129.7kg of 2-cyanoimino-1, 3-thiazolidine, 350kg of dichloromethane and 120.96kg of tetramethylguanidine into a reaction kettle, cooling to 10-15 ℃, keeping the temperature, adding 162.0kg of 2-chloro-5-chloromethylpyridine into the reaction kettle, stirring and reacting at 40 ℃ for 11 hours after the addition is finished, adding hydrochloric acid into the reaction kettle, adjusting the pH of a reaction solution to 4, recovering a solvent, adding 450kg of an n-butanol water mixed solution with the mass percentage concentration of 40% into the reaction kettle, recrystallizing, filtering, drying a filter cake, and obtaining 242.8kg of thiacloprid, wherein the yield is 96.1%, and the content is 98.5%.
Example 9
A synthetic method of thiacloprid comprises the following steps: adding 129.7kg of 2-cyanoimino-1, 3-thiazolidine, 415kg of dichloromethane and 120.96kg of tetramethylguanidine into a reaction kettle, cooling to 10-15 ℃, keeping the temperature, adding 162.0kg of 2-chloro-5-chloromethylpyridine into the reaction kettle, stirring and reacting at 45 ℃ for 15 hours after the addition is finished, adding hydrochloric acid into the reaction kettle, adjusting the pH of a reaction solution to 2, recovering the solvent, adding 400kg of an n-butanol water mixed solution with the mass percentage concentration of 20% into the reaction kettle, recrystallizing, filtering, drying a filter cake, and obtaining 246.6kg of thiacloprid, the yield is 97.6%, and the content is 97.5%.
Example 10
A synthetic method of thiacloprid comprises the following steps: adding 128.4kg of 2-cyanoimino-1, 3-thiazolidine, 350kg of chloroform and 117.5kg of tetramethylguanidine into a reaction kettle, cooling to 20-25 ℃, keeping the temperature, adding 162.0kg of 2-chloro-5-chloromethylpyridine into the reaction kettle, stirring and reacting for 8 hours at 25 ℃ after the addition is finished, adding hydrochloric acid into the reaction kettle, adjusting the pH of a reaction solution to 3, recovering a solvent, adding 350kg of an n-butanol-water mixed solution with the mass percentage concentration of 30% into the reaction kettle, recrystallizing, filtering, and drying a filter cake to obtain 242.1kg of thiacloprid, wherein the yield is 95.8%, and the content is 98.5%.
Example 11
A synthetic method of thiacloprid comprises the following steps: adding 128.4kg of 2-cyanoimino-1, 3-thiazolidine, 450kg of chloroform and 117.5kg of tetramethylguanidine into a reaction kettle, cooling to 20-25 ℃, keeping the temperature, adding 162.0kg of 2-chloro-5-chloromethylpyridine into the reaction kettle, stirring and reacting at 30 ℃ after the addition is finished to obtain a reaction liquid, taking the liquid phase of the reaction liquid, controlling the content of the 2-chloro-5-chloromethylpyridine to be less than or equal to 1%, adding hydrochloric acid into the reaction kettle, adjusting the pH of the reaction liquid to 1, recovering the solvent, adding 500kg of an n-butanol water mixed solution with the mass percentage concentration of 20% into the reaction kettle, recrystallizing, performing suction filtration, and drying a filter cake to obtain 240.6kg of thiacloprid, wherein the yield is 95.2%, and the content is 98.9%.
Example 12
A synthetic method of thiacloprid comprises the following steps: adding 128.4kg of 2-cyanoimino-1, 3-thiazolidine, 380kg of chloroform and 117.5kg of tetramethylguanidine into a reaction kettle, cooling to 20-25 ℃, keeping the temperature, adding 162.0kg of 2-chloro-5-chloromethylpyridine into the reaction kettle, stirring and reacting at 45 ℃ after the addition is finished to obtain a reaction liquid, controlling the 2-chloro-5-chloromethylpyridine to be less than or equal to 1% in a liquid phase of the reaction liquid, adding hydrochloric acid into the reaction kettle, adjusting the pH of the reaction liquid to 6, recovering a solvent, adding 350kg of n-butanol water mixed solution with the mass percentage concentration of 50% into the reaction kettle, recrystallizing, performing suction filtration, and drying a filter cake to obtain 244.1kg of thiacloprid, wherein the yield is 96.6%, and the content is 97.9%.
Claims (7)
1. A method for synthesizing thiacloprid is characterized by comprising the following steps: the method comprises the following steps:
① adding 2-cyanoimino-1, 3-thiazolidine, a solvent and an organic base into a reaction kettle, cooling to 0-30 ℃, keeping the temperature, adding 2-chloro-5-chloromethylpyridine into the reaction kettle, stirring and reacting at 20-50 ℃ for 5-15 hours after the addition is finished, adding hydrochloric acid into the reaction kettle, and adjusting the pH of a reaction solution to 1-6 to obtain a mixed solution;
the organic base is N, N-dimethylguanidine or tetramethylguanidine; the solvent is an alcohol solvent or chlorinated hydrocarbon; wherein the molar mass ratio of the 2-cyanoimino-1, 3-thiazolidine, the solvent, the organic base and the 2-chloro-5-chloromethylpyridine is 1.0-1.05 mol: 300-500 g: 1.0-1.1 mol: 1.0 mol;
② the mixed solution of step ① is post-treated according to the difference of the solvent:
when the solvent is an alcohol solvent, adding water into the reaction kettle for recrystallization, performing suction filtration, and drying a filter cake to obtain thiacloprid; wherein the mass ratio of water to the alcohol solvent is 1-4: 1;
and when the solvent is chlorohydrocarbon, carrying out reduced pressure distillation on the mixed solution to remove the solvent, then adding the alcohol-water mixed solution into the reaction kettle for recrystallization, carrying out suction filtration, and drying a filter cake to obtain thiacloprid.
2. The method for synthesizing thiacloprid according to claim 1, which is characterized by comprising the following steps: the organic base is tetramethylguanidine.
3. The method for synthesizing thiacloprid according to claim 1, which is characterized by comprising the following steps: the alcohol-water mixed solution is n-butyl alcohol water solution or methanol water solution, and the mass percentage concentration of the alcohol-water mixed solution is 20-50%.
4. The method for synthesizing thiacloprid according to claim 1, which is characterized by comprising the following steps: and adding hydrochloric acid into the reaction kettle, and adjusting the pH of the reaction solution to 3-4.
5. The method for synthesizing thiacloprid according to claim 1, which is characterized by comprising the following steps: the molar mass ratio of the 2-cyanoimino-1, 3-thiazolidine, the solvent, the organic base and the 2-chloro-5-chloromethylpyridine is 1.0-1.02 mol: 350-450 g: 1.0-1.05 mol: 1.0 mol.
6. The method for synthesizing thiacloprid according to claim 1, which is characterized by comprising the following steps: the alcohol solvent is butanol.
7. The method for synthesizing thiacloprid according to claim 1, which is characterized by comprising the following steps: the chlorinated hydrocarbon is dichloromethane or chloroform.
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| CN103797008A (en) * | 2011-09-02 | 2014-05-14 | 拜耳知识产权有限责任公司 | Method for producing [3-[(6-chlor-3-pridinyl)methyl]-2-thiazolidinylidene]cyanamide |
| CN102399216A (en) * | 2011-11-30 | 2012-04-04 | 利民化工股份有限公司 | Method for producing thiacloprid technical |
| WO2017048628A1 (en) * | 2015-09-15 | 2017-03-23 | Bayer Cropscience Lp | Procedure for the preparation of 2-cyanoimino-1,3-thiazolidine |
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