CN112625001A - Synthesis method of 1, 2-benzisothiazolin-3-ketone - Google Patents
Synthesis method of 1, 2-benzisothiazolin-3-ketone Download PDFInfo
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- CN112625001A CN112625001A CN202011410678.9A CN202011410678A CN112625001A CN 112625001 A CN112625001 A CN 112625001A CN 202011410678 A CN202011410678 A CN 202011410678A CN 112625001 A CN112625001 A CN 112625001A
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- C07—ORGANIC CHEMISTRY
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- C07D275/00—Heterocyclic compounds containing 1,2-thiazole or hydrogenated 1,2-thiazole rings
- C07D275/04—Heterocyclic compounds containing 1,2-thiazole or hydrogenated 1,2-thiazole rings condensed with carbocyclic rings or ring systems
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Abstract
The invention discloses a method for synthesizing 1, 2-benzisothiazolin-3-ketone, which comprises the following steps: (1) adding 1, 2-dimercaptoethane and potassium carbonate at room temperature at one time, stirring and slowly heating to obtain mercapto potassium salt; (2) adding 1, 2-dichloroethane as a solvent, adding o-chlorobenzonitrile, controlling the temperature to be less than 80 ℃, and reacting until the liquid phase residue of the o-chlorobenzonitrile is less than 1%; (3) introducing chlorine into the obtained filtrate at 40-50 ℃ for oxidative cyclization reaction to generate a mixture of a BIT intermediate and BIT; (4) heating the mixture to 80 ℃, preserving the temperature until the BIT intermediate is completely converted into BIT, slowly cooling to 50 ℃, performing suction filtration to obtain a BIT product, performing suction filtration, purifying and drying on the BIT product to obtain a purified BIT product. The method has the advantages of short production line, less equipment, simple operation, convenient management, higher yield, low raw material cost, recyclable raw materials, low environmental protection pressure and the like.
Description
Technical Field
The invention belongs to the field of chemical engineering, and particularly relates to a synthetic method of 1, 2-benzisothiazolin-3-one.
Background
The existing 1, 2-benzisothiazolin-3-ketone synthesis process mainly comprises 3 processes: firstly, preparing dithiobenzoic acid by taking o-aminobenzoic acid as a raw material, and preparing BIT through acyl chlorination, chlorination and ammoniation; the second method is to take o-chlorobenzonitrile or o-chlorobenzamide or o-chlorobenzaldehyde as raw materials, react with mercaptan, and then carry out oxidation cyclization to prepare 1, 2-benzisothiazolinone; thirdly, synthesizing the 1, 2-benzisothiazolin-3-ketone compound by cyclization reaction of the oxide of the 1, 3-benzooxanthin-4-ketone.
The prior art has too complex process, so that the production line is too long, a large number of required reaction kettles and operators are needed, and the reaction time is prolonged. These conditions lead to high production cost and easily cause more problems (such as safety, environmental protection and field management). And the raw materials of production demand are difficult to obtain, and the promotion of output has greatly been influenced, has reduced the company profit.
In addition, the methyl mercaptan is used as a raw material, has strong toxicity and is extremely harmful to human bodies. The oxide of the 1, 3-benzooxanthin-4-ketone is used as a raw material and is not easy to obtain.
Disclosure of Invention
The invention aims to provide a method for synthesizing 1, 2-benzisothiazolin-3-one, which can solve the problems of low raw material yield, high cost, high toxicity, low utilization rate, complex steps, long reaction time, more byproducts, great pollution to the environment and the like in the prior art.
In order to achieve the purpose, the invention adopts the following technical scheme: a method for synthesizing 1, 2-benzisothiazolin-3-ketone is characterized by comprising the following steps: which comprises the following steps of,
(1) adding 1, 2-dimercaptoethane and potassium carbonate into a flask at room temperature at one time, stirring, slowly heating to 80 ℃, and preserving heat for 1h to obtain mercapto potassium salt;
(2) adding 1, 2-dichloroethane as a solvent into the sulfhydryl potassium salt generated in the step (1), adding o-chlorobenzonitrile, controlling the temperature to be less than 80 ℃ for reaction, and ending the reaction until the liquid phase residue of the o-chlorobenzonitrile is less than 1%;
(3) carrying out suction filtration on the solution obtained in the step (2), removing excessive potassium carbonate and generated potassium bicarbonate to obtain a filtrate, and introducing chlorine into the filtrate at 40-50 ℃ to carry out oxidative cyclization reaction to generate a mixture of a BIT intermediate and BIT;
(4) and (4) heating the mixture of the BIT intermediate and the BIT in the step (3) to 80 ℃, preserving the heat until the BIT intermediate is completely converted into the BIT, slowly cooling to 50 ℃, performing suction filtration to obtain a BIT product, performing suction filtration, purifying and drying on the BIT product to obtain a purified BIT product.
Further, 1, 2-dimercaptoethane: potassium carbonate: 1, 2-dichloroethane: the mol ratio of the o-chlorobenzonitrile is 0.4-0.7:1.2-1.5:2.1-2.3: 1.
Further, 1, 2-dimercaptoethane: potassium carbonate: 1, 2-dichloroethane: the molar ratio of o-chlorobenzonitrile is 0.56:1.39:2.22: 1.
Further, in the step (2), the o-chlorobenzonitrile is added in two times, and half of the amount is added in one time.
Further, the purification method in the step (4) comprises the following steps: rinsing and filtering with a 1, 2-dichloroethane solvent 2 times the mass of the BIT product, and rinsing and filtering with water of the same mass.
Further, the incubation time of the mixture of the BIT intermediate and the BIT in the step (4) is 3 h.
Further, the 1, 2-dichloroethane solvent in the step (2) can be recycled; and (4) treating the potassium carbonate and the potassium bicarbonate which are extracted and filtered out in the step (3) to obtain the potassium carbonate which can be recycled.
Furthermore, the 1, 2-dichloroethane solvent, potassium carbonate and potassium bicarbonate are mechanically used for 2 times, and then re-purified and reused.
Further, the time interval between the two additions of the o-chlorobenzonitrile is 0.5 to 1 hour.
Further, it comprises the following steps,
(1) at room temperature, adding 94g of 1, 2-dimercaptoethane and 345g of potassium carbonate into a flask at one time, stirring, slowly heating to 80 ℃, and preserving heat for 1h to obtain mercapto potassium salt;
(2) adding 400g of 1, 2-dichloroethane as a solvent into the mercapto potassium salt generated in the step (1), separating for 0.5 hour twice, adding 123.75 of o-chlorobenzonitrile once each time, controlling the temperature to be less than 80 ℃ for reaction, and ending the reaction until the liquid phase residue of the o-chlorobenzonitrile is less than 1%;
(3) carrying out suction filtration on the solution obtained in the step (2), removing excessive potassium carbonate and generated potassium bicarbonate to obtain a filtrate, and introducing chlorine into the filtrate at 40-50 ℃ to carry out oxidative cyclization to generate a BIT intermediate and a BIT mixture;
(4) and (3) heating the mixture of the BIT intermediate and the BIT in the step (3) to 80 ℃, keeping the temperature for 3 hours, completely converting the BIT intermediate into the BIT, slowly cooling to 50 ℃, performing suction filtration to obtain a BIT product, rinsing and performing suction filtration by using a 1, 2-dichloroethane solvent with the mass 2 times that of the solid, continuously rinsing and performing suction filtration by using water with the same mass, and drying to obtain 253g of BIT pure product with the molar yield of 93.08%.
Compared with the prior art, the invention has the following beneficial effects:
(1) the raw materials used in the invention have large market supply amount, low price and low economic cost.
(2) The method has the advantages of short production line, less equipment, simple operation, convenient management and higher yield.
(3) The 1, 2-dichloroethane solvent and the potassium carbonate raw materials adopted by the invention can be recycled, the loss amount is lower, and the production cost is reduced.
(4) The invention adopts raw materials which are less harmful or harmless to human bodies, no waste gas is generated in the reaction process, the amount of waste water is less, and the environmental protection pressure of companies is greatly reduced.
Detailed Description
In order to further illustrate the technical means adopted and the technical effects achieved by the present invention, the following detailed description is made with reference to the embodiments.
The invention provides a method for synthesizing 1, 2-benzisothiazolin-3-ketone, which comprises the following steps,
(1) adding 1, 2-dimercaptoethane and potassium carbonate into a flask at room temperature at one time, stirring, slowly heating to 80 ℃, and preserving heat for 1h to obtain mercapto potassium salt;
(2) adding 1, 2-dichloroethane as a solvent into the sulfhydryl potassium salt generated in the step (1), adding o-chlorobenzonitrile, controlling the temperature to be less than 80 ℃ for reaction, and ending the reaction until the liquid phase residue of the o-chlorobenzonitrile is less than 1%;
(3) carrying out suction filtration on the solution obtained in the step (2), removing excessive potassium carbonate and generated potassium bicarbonate to obtain a filtrate, and introducing chlorine into the filtrate at 40-50 ℃ to carry out oxidative cyclization reaction to generate a mixture of a BIT intermediate and BIT;
(4) and (4) heating the mixture of the BIT intermediate and the BIT in the step (3) to 80 ℃, preserving the heat until the BIT intermediate is completely converted into the BIT, slowly cooling to 50 ℃, performing suction filtration to obtain a BIT product, performing suction filtration, purifying and drying on the BIT product to obtain a purified BIT product.
1, 2-dimercaptoethane: potassium carbonate: 1, 2-dichloroethane: the mol ratio of the o-chlorobenzonitrile is 0.4-0.7:1.2-1.5:2.1-2.3: 1.
More preferably, 1, 2-dimercaptoethane: potassium carbonate: 1, 2-dichloroethane: the optimum molar ratio of o-chlorobenzonitrile is 0.56:1.39:2.22: 1.
In the step (2), the o-chlorobenzonitrile is added twice, and half of the o-chlorobenzonitrile is added once each time.
The purification method in the step (4) comprises the following steps: rinsing and filtering with a 1, 2-dichloroethane solvent 2 times the mass of the BIT product, and rinsing and filtering with water of the same mass.
And (4) keeping the temperature of the mixture of the BIT intermediate and the BIT for 3 h.
The 1, 2-dichloroethane solvent in the step (2) and the potassium carbonate and the potassium bicarbonate in the step (3) can be recycled. The 1, 2-dichloroethane solvent, potassium carbonate and potassium bicarbonate are reused after being reused for 2 times.
The time interval between the two additions of the o-chlorobenzonitrile is 0.5 to 1 hour.
The invention relates to a method for synthesizing 1, 2-benzisothiazolin-3-ketone, which comprises the following steps:
(1) at room temperature, adding 94g of 1, 2-dimercaptoethane and 345g of potassium carbonate into a flask at one time, stirring, slowly heating to 80 ℃, and preserving heat for 1h to obtain mercapto potassium salt;
(2) adding 400g of 1, 2-dichloroethane as a solvent into the mercapto potassium salt generated in the step (1), separating for 0.5 hour twice, adding 123.75 of o-chlorobenzonitrile once each time, controlling the temperature to be less than 80 ℃ for reaction, and ending the reaction until the liquid phase residue of the o-chlorobenzonitrile is less than 1%;
(3) carrying out suction filtration on the solution obtained in the step (2), removing excessive potassium carbonate and generated potassium bicarbonate to obtain a filtrate, and introducing chlorine into the filtrate at 40-50 ℃ to carry out oxidative cyclization to generate a BIT intermediate and a BIT mixture;
(4) and (3) heating the mixture of the BIT intermediate and the BIT in the step (3) to 80 ℃, keeping the temperature for 3 hours, completely converting the BIT intermediate into the BIT, slowly cooling to 50 ℃, performing suction filtration to obtain a BIT product, rinsing and performing suction filtration by using a 1, 2-dichloroethane solvent with the mass 2 times that of the solid, continuously rinsing and performing suction filtration by using water with the same mass, and drying to obtain 253g of BIT pure product with the molar yield of 93.08%.
Example 1:
94g of 1, 2-dimercaptoethane and 345g of potassium carbonate are added into a flask at room temperature in one step, stirred and slowly heated to 80 ℃, and the temperature is kept for 1 hour to generate potassium mercapto salt. Then 400g of 1, 2-dichloroethane is added as a solvent, 247.5g of o-chlorobenzonitrile is added averagely in 2 times, the temperature is controlled to be less than 80 ℃, and 0.84% of o-chlorobenzonitrile liquid phase remains after 4 hours. Filtering to remove excessive potassium carbonate and generated potassium bicarbonate, introducing chlorine into the obtained filtrate at 40-50 deg.C, and stopping introducing chlorine when the liquid phase residue of the raw material is less than 12%. Heating to 80 ℃, keeping the temperature for 3 hours, slowly cooling to 50 ℃, filtering to obtain a BIT product, rinsing and filtering with a 1, 2-dichloroethane solvent with 2 times of the mass of the solid, continuously rinsing and filtering with water with the same mass, and drying to obtain 253g of BIT pure product with the content of 99.1 percent and the yield of 93.08 percent.
Example 2:
the potassium carbonate and the potassium bicarbonate in example 1 are treated to obtain potassium carbonate, and the 1, 2-dichloroethane recovered in example 1 is used.
68g of 1, 2-dimercaptoethane and 298g of potassium carbonate obtained after treatment are added into a flask at room temperature at one time, stirred and slowly heated to 80 ℃, and the temperature is kept for 1h to generate potassium mercapto salt. Then 375g of 1, 2-dichloroethane is added as a solvent, 247.5g of o-chlorobenzonitrile is added averagely in 2 times, the temperature is controlled to be less than 80 ℃, and 0.86% of o-chlorobenzonitrile liquid phase remains after 4 hours. Filtering to remove excessive potassium carbonate and generated potassium bicarbonate, introducing chlorine into the obtained filtrate at 40-50 deg.C, and stopping introducing chlorine when the liquid phase residue of the raw material is less than 12%. Heating to 80 ℃, keeping the temperature for 3 hours, slowly cooling to 50 ℃, filtering to obtain a BIT product, rinsing and filtering with a 1, 2-dichloroethane solvent with 2 times of the mass of the solid, continuously rinsing and filtering with water with the same mass, and drying to obtain 246g of BIT pure product with the content of 99.08 percent and the molar yield of 90.51 percent.
Example 3:
the potassium carbonate and the potassium bicarbonate in the example 2 are treated to obtain the potassium carbonate, and the 1, 2-dichloroethane recovered in the example 2 is used for indiscriminate application.
119g of 1, 2-dimercaptoethane and 373g of the treated potassium carbonate are added into a flask at room temperature, stirred and slowly heated to 80 ℃, and the temperature is kept for 1h to generate the mercapto potassium salt. Then 410g of 1, 2-dichloroethane is added as a solvent, 247.5g of o-chlorobenzonitrile is added averagely in 2 times, the temperature is controlled to be less than 80 ℃, and 0.81% of o-chlorobenzonitrile liquid phase remains after 4 hours. Filtering to remove excessive potassium carbonate and generated potassium bicarbonate, introducing chlorine into the obtained filtrate at 40-50 deg.C, and stopping introducing chlorine when the liquid phase residue of the raw material is less than 12%. Heating to 80 ℃, keeping the temperature for 3 hours, slowly cooling to 50 ℃, filtering to obtain a BIT product, rinsing and filtering with a 1, 2-dichloroethane solvent with 2 times of the mass of the solid, continuously rinsing and filtering with water with the same mass, and drying to obtain 249.2g of a purified BIT product with the content of 99.11 percent and the molar yield of 91.69 percent.
The above embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.
Claims (10)
1. A method for synthesizing 1, 2-benzisothiazolin-3-ketone is characterized by comprising the following steps: which comprises the following steps of,
(1) adding 1, 2-dimercaptoethane and potassium carbonate into a flask at room temperature at one time, stirring, slowly heating to 80 ℃, and preserving heat for 1h to obtain mercapto potassium salt;
(2) adding 1, 2-dichloroethane as a solvent into the sulfhydryl potassium salt generated in the step (1), adding o-chlorobenzonitrile, controlling the temperature to be less than 80 ℃ for reaction, and ending the reaction until the liquid phase residue of the o-chlorobenzonitrile is less than 1%;
(3) carrying out suction filtration on the solution obtained in the step (2), removing excessive potassium carbonate and generated potassium bicarbonate to obtain a filtrate, and introducing chlorine into the filtrate at 40-50 ℃ to carry out oxidative cyclization reaction to generate a mixture of a BIT intermediate and BIT;
(4) and (4) heating the mixture of the BIT intermediate and the BIT in the step (3) to 80 ℃, preserving the heat until the BIT intermediate is completely converted into the BIT, slowly cooling to 50 ℃, performing suction filtration to obtain a BIT product, performing suction filtration, purifying and drying on the BIT product to obtain a purified BIT product.
2. The method of synthesizing 1, 2-benzisothiazolin-3-one according to claim 1, characterized in that: 1, 2-dimercaptoethane: potassium carbonate: 1, 2-dichloroethane: the mol ratio of the o-chlorobenzonitrile is 0.4-0.7:1.2-1.5:2.1-2.3: 1.
3. The method of synthesizing 1, 2-benzisothiazolin-3-one according to claim 2, characterized in that: 1, 2-dimercaptoethane: potassium carbonate: 1, 2-dichloroethane: the molar ratio of o-chlorobenzonitrile is 0.56:1.39:2.22: 1.
4. The method of synthesizing 1, 2-benzisothiazolin-3-one according to claim 1, characterized in that: in the step (2), the o-chlorobenzonitrile is added twice, and half of the o-chlorobenzonitrile is added once each time.
5. The method of synthesizing 1, 2-benzisothiazolin-3-one according to claim 1, characterized in that: the purification method in the step (4) comprises the following steps: rinsing and filtering with a 1, 2-dichloroethane solvent 2 times the mass of the BIT product, and rinsing and filtering with water of the same mass.
6. The method of synthesizing 1, 2-benzisothiazolin-3-one according to claim 1, characterized in that: and (4) keeping the temperature of the mixture of the BIT intermediate and the BIT for 3 h.
7. The method of synthesizing 1, 2-benzisothiazolin-3-one according to claim 1, characterized in that:
the 1, 2-dichloroethane solvent in the step (2) can be recycled;
and (4) treating the potassium carbonate and the potassium bicarbonate which are extracted and filtered out in the step (3) to obtain the potassium carbonate which can be recycled.
8. The method of synthesizing 1, 2-benzisothiazolin-3-one according to claim 7, wherein: the 1, 2-dichloroethane solvent, potassium carbonate and potassium bicarbonate are reused after being reused for 2 times.
9. The method of synthesizing 1, 2-benzisothiazolin-3-one according to claim 1, characterized in that: the time interval between the two additions of the o-chlorobenzonitrile is 0.5 to 1 hour.
10. The method of synthesizing 1, 2-benzisothiazolin-3-one according to claim 1, characterized in that: which comprises the following steps of,
(1) at room temperature, adding 94g of 1, 2-dimercaptoethane and 345g of potassium carbonate into a flask at one time, stirring, slowly heating to 80 ℃, and preserving heat for 1h to obtain mercapto potassium salt;
(2) adding 400g of 1, 2-dichloroethane as a solvent into the mercapto potassium salt generated in the step (1), separating for 0.5 hour twice, adding 123.75 of o-chlorobenzonitrile once each time, controlling the temperature to be less than 80 ℃ for reaction, and ending the reaction until the liquid phase residue of the o-chlorobenzonitrile is less than 1%;
(3) carrying out suction filtration on the solution obtained in the step (2), removing excessive potassium carbonate and generated potassium bicarbonate to obtain a filtrate, and introducing chlorine into the filtrate at 40-50 ℃ to carry out oxidative cyclization to generate a BIT intermediate and a BIT mixture;
(4) and (3) heating the mixture of the BIT intermediate and the BIT in the step (3) to 80 ℃, keeping the temperature for 3 hours, completely converting the BIT intermediate into the BIT, slowly cooling to 50 ℃, performing suction filtration to obtain a BIT product, rinsing and performing suction filtration by using a 1, 2-dichloroethane solvent with the mass 2 times that of the solid, continuously rinsing and performing suction filtration by using water with the same mass, and drying to obtain 253g of BIT pure product, wherein the molar yield of the pure product is 93.08%.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102491955A (en) * | 2011-12-08 | 2012-06-13 | 上海易摩生物科技有限公司 | Process method for synthesizing 1, 2-benzisothiazdin-3-ketone |
| CN103130738A (en) * | 2013-03-26 | 2013-06-05 | 寿光新泰精细化工有限公司 | Method for synthesizing 1,2-benzisothiazolin-3-one |
| CN104817517A (en) * | 2015-04-24 | 2015-08-05 | 大丰跃龙化学有限公司 | Synthetic method of 1, 2-benzisothiazolin-3-one |
| CN111559986A (en) * | 2020-06-22 | 2020-08-21 | 大连百傲化学股份有限公司 | Purification method of 1, 2-benzisothiazolin-3-ketone |
| CN111574472A (en) * | 2020-06-30 | 2020-08-25 | 大连百傲化学股份有限公司 | Synthesis method of 1, 2-benzisothiazolin-3-ketone compound |
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- 2020-12-04 CN CN202011410678.9A patent/CN112625001A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102491955A (en) * | 2011-12-08 | 2012-06-13 | 上海易摩生物科技有限公司 | Process method for synthesizing 1, 2-benzisothiazdin-3-ketone |
| CN103130738A (en) * | 2013-03-26 | 2013-06-05 | 寿光新泰精细化工有限公司 | Method for synthesizing 1,2-benzisothiazolin-3-one |
| CN104817517A (en) * | 2015-04-24 | 2015-08-05 | 大丰跃龙化学有限公司 | Synthetic method of 1, 2-benzisothiazolin-3-one |
| CN111559986A (en) * | 2020-06-22 | 2020-08-21 | 大连百傲化学股份有限公司 | Purification method of 1, 2-benzisothiazolin-3-ketone |
| CN111574472A (en) * | 2020-06-30 | 2020-08-25 | 大连百傲化学股份有限公司 | Synthesis method of 1, 2-benzisothiazolin-3-ketone compound |
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