CN114989104B - Synthesis method of triallyl isocyanurate - Google Patents
Synthesis method of triallyl isocyanurate Download PDFInfo
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- CN114989104B CN114989104B CN202210918788.9A CN202210918788A CN114989104B CN 114989104 B CN114989104 B CN 114989104B CN 202210918788 A CN202210918788 A CN 202210918788A CN 114989104 B CN114989104 B CN 114989104B
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D251/00—Heterocyclic compounds containing 1,3,5-triazine rings
- C07D251/02—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings
- C07D251/12—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings having three double bonds between ring members or between ring members and non-ring members
- C07D251/26—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings having three double bonds between ring members or between ring members and non-ring members with only hetero atoms directly attached to ring carbon atoms
- C07D251/30—Only oxygen atoms
- C07D251/34—Cyanuric or isocyanuric esters
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Abstract
The invention discloses a method for continuously synthesizing triallyl isocyanurate (TAIC) by using a tubular reactor with axial stirring, belonging to the technical field of organic synthesis processes. The method comprises the following specific steps: firstly, dehydrating and deaminating urea and sodium carbonate in a DMF solvent to obtain DMF slurry of sodium cyanate, pumping the DMF slurry of sodium cyanate and chloropropene into a tubular reactor with axial stirring by using a slurry metering pump and a liquid metering pump respectively according to a certain proportion for substitution and cyclization reaction, filtering, desalting and rectifying to obtain triallyl isocyanurate. Compared with the traditional batch synthesis method, the method provided by the invention overcomes the defect that cyanate (sodium cyanate and potassium cyanate) needs to be dried and then reacts in the prior art, avoids the generation of byproducts such as acyclic allyl cyanate and di-or mono-substituted cyanuric acid, and reduces the hydrolysis of chloropropene. The method has the advantages of simple operation, high product yield and good quality, and is more favorable for industrial production.
Description
Technical Field
The invention relates to a method for continuously synthesizing triallyl isocyanurate by using a tubular reactor.
Background
Triallyl isocyanurate, which is called cross-linking agent TAIC for short, has the chemical name of 1,3, 5-triallyl-s-triazine-2, 4, 6-trione, is oily liquid or hexagonal crystal at room temperature, is easy to oxidize for a long time and is light yellow. Melting point of 19-22 ℃, boiling point: 144 ℃ (400 Pa), molecular formula: c 12 H 15 N 3 O 3 Molecular weight: 249.27, structural formula:
triallyl isocyanurate is a multifunctional olefin monomer containing aromatic heterocycle, is widely used for various thermoplastics, ion exchange resin, crosslinking agents, modifiers, auxiliary vulcanizing agents and the like of special rubber, and intermediates of photocuring coating, photoresist, flame retardant and the like, is an auxiliary agent of a novel polymer material with wide application, and has increasingly expanded market demand. The methods reported so far are mainly as follows.
US2894950A discloses a method for synthesizing TAIC from cyanuric acid as a raw material in a strong alkali aqueous solution at 40-50 ℃. Although the method reduces the cost by using water as a solvent, the reaction rate is slow, the solution is alkaline (pH = 11-13), chloropropene is hydrolyzed into allyl alcohol, excessive chloropropene is needed to improve the conversion rate of cyanuric acid, and in addition, products contain di-substituted and mono-substituted byproducts of cyanuric acid, so that the subsequent purification difficulty is high, and the purity of TAIC products is low.
In order to solve the defect that allyl alcohol is generated from chloropropene in a strong alkali aqueous solution, U.S. Pat. No. 2,2536849A discloses a reaction system of chlorobenzene and other organic solvents, and TEA is used as an acid-binding agent, but the amount of TEA used in the method is large, the production cost is relatively increased, and industrial production cannot be carried out.
The synthesis principle and the test process of TAIC, populon, high petrochemical, the fourth stage, pages 8 to 11, 2004 report that isocyanuric acid is used as a raw material, firstly reacts with sodium hydroxide to prepare isocyanuric acid trisodium salt, and then reacts with 3.3 times of chloropropene in DMF to carry out a trisubstitution reaction to synthesize TAIC. This batch synthesis has the following disadvantages: (1) The best solvent for preparing the trisodium isocyanurate is water, and the trisodium isocyanurate easily absorbs carbon dioxide and water in the air, so a vacuum drying oven is needed during drying, and if an air-blast drying oven is used, the substitution reaction yield is low; (2) The recovery difficulty of excessive chloropropene is high because the chloropropene has high solubility in DMF and the excessive chloropropene is difficult to be distilled and recovered when the kettle temperature is more than 140 ℃.
US8198431B2 discloses a process for preparing triallyl cyanurate (TAC) with Cu 2+ As a catalyst, TAIC is generated by claisen rearrangement in DMF at 110-140 ℃. The method has the defects of high raw material cost, easy polymerization at high temperature and the like, and is difficult to realize industrial production.
US4196289A discloses a process for the synthesis of TAIC at 110-150 ℃ using cyanate (sodium cyanate, potassium cyanate) and chloropropene as raw materials, N-dimethylformamide as solvent, cuprous chloride, potassium bromide or triethylamine as catalyst. Although the method achieves the purpose of simultaneously carrying out chloropropene substitution and trimerization cyclization reaction of isocyanate in the same reaction kettle, the reaction not only generates TAIC products, but also generates acyclic allyl cyanate or dimer and other impurities, so that the product is difficult to separate, the reaction time is long, and the product is dark in color.
Disclosure of Invention
The invention provides a method for continuously synthesizing triallyl isocyanurate, which can overcome the defect that cyanate (sodium cyanate and potassium cyanate) needs to be dried and then reacts in the prior art, avoid side reactions of acyclic allyl cyanate and di-substitution or mono-substitution of cyanuric acid and the like, and reduce the hydrolysis of chloropropene. A tubular reactor with axial stirring is used as a reaction carrier, and DMF slurry of sodium cyanate and chloropropene are synchronously pushed in the reactor, so that the defect that the sodium cyanate needs to be dried and then reacts is overcome; fully mixing, and reducing the generation of byproducts such as di-substitution or mono-substitution of cyanuric acid; the cyclization temperature is raised to 170-175 ℃, the formation of allyl cyanate without cyclization is avoided, the reaction speed is accelerated, the product quality is good, and the yield is high.
The technical scheme for realizing the invention is as follows:
the invention provides a method for continuously synthesizing triallyl isocyanurate, which specifically comprises the following steps: (1) synthesis of sodium cyanate: sequentially adding DMF, urea and sodium carbonate into a reaction kettle, heating to 140-145 ℃, preserving heat for 10-11 h, deaminating and dehydrating to obtain DMF slurry of sodium cyanate; (2) substitution reaction: controlling the feeding speed by a pump to synchronously push the DMF slurry of sodium cyanate and chloropropene into a tubular reactor 1 with axial stirring for substitution reaction, controlling the temperature of the tubular reactor 1 with axial stirring to be 40-45 ℃, keeping the material retention time to be 30-45 s, and feeding the reaction liquid into a tubular reactor 2; (3) cyclization reaction: controlling the temperature of the tubular reactor 2 with axial stirring to be 170-175 ℃, keeping the material for 25-35 s, desalting the reaction liquid, flowing into a rectifying still, and rectifying to obtain the triallyl isocyanurate.
The reaction formula is as follows:
according to the method, urea and chloropropene are used as raw materials, a tubular reactor is adopted to continuously synthesize triallyl isocyanurate, a slurry metering pump and a liquid metering pump are respectively used to transfer DMF (dimethyl formamide) slurry of sodium cyanate and chloropropene obtained after deamination and dehydration of urea into the tubular reactor 1 with axial stirring for substitution reaction, the defect that the traditional sodium cyanate needs to be dried and then reacted is overcome, and the generation of byproducts such as di-substitution or mono-substitution cyanuric acid is reduced; by increasing the cyclization reaction temperature, the formation of acyclic allyl cyanate is reduced, the reaction time is reduced, the product quality and yield are improved, and the method has important significance for industrial production.
Preferably, in the stage of synthesis of sodium cyanate, the molar ratio of sodium carbonate to urea is 1:1.9 to 1:2.0, the conversion of urea in this molar ratio is preferred.
Preferably, the temperature of the sodium cyanate in the synthesis stage is controlled between 140 ℃ and 145 ℃, the urea conversion is incomplete below 140 ℃, and the energy consumption is increased above 145 ℃.
Preferably, the heat preservation time of the synthesis stage of the sodium cyanate is 10-11 hours, and the urea is remained below 10 hours.
Preferably, in the substitution reaction stage, the molar ratio of sodium cyanate to chloropropene is 1:1.05 to 1:1.10, the mol ratio is better than the conversion rate of the chloropropene.
Preferably, the temperature in the substitution reaction stage is controlled to be 40-45 ℃ and lower than 40 ℃, and the chloropropene conversion is incomplete.
Preferably, the temperature holding time is controlled to be 30-45 s in the substitution reaction stage, the conversion rate of raw materials is relatively high in the reaction time, and the quality of products can be guaranteed.
Preferably, the temperature in the cyclization reaction stage is controlled to 170 ℃ to 175 ℃ and is lower than 170 ℃, and a large amount of acyclic allyl cyanate by-products is produced.
Preferably, in the cyclization reaction stage, the holding time is controlled to be 25-35 s, the conversion rate of raw materials in the reaction time is relatively high, and the quality of products can be ensured.
Compared with the prior art, the invention has the advantages that:
1) The tubular reactor with axial stirring is adopted as a reaction carrier to carry out continuous reaction, the temperature and the feeding speed are simple and controllable, the reaction time is short, the formation of byproducts is effectively avoided, and the selectivity is high;
2) Sodium cyanate prepared by dehydration and deamination directly carries out substitution reaction with chloropropene, thus overcoming the defect that sodium cyanate needs to be dried and then reacts;
3) The DMF slurry of the sodium cyanate is fully mixed with chloropropene, so that the generation of subsequent byproducts such as di-substitution or mono-substitution of cyanuric acid is reduced;
4) The temperature is increased in the cyclization reaction stage, so that the formation of acyclic allyl cyanate is reduced, the reaction time is shortened, and the product quality and yield are improved;
5) The reaction process and the post-treatment have continuity, the quality is stable, and the automatic production is convenient.
Detailed Description
Example 1
A thermometer and a water separator were mounted on a 500 mL three-necked flask, and a condenser tube was mounted on the water separator. 24lg N, N-Dimethylformamide (DMF) and Na were added in sequence 2 CO 3 (76.4 g, 0.72 mol) and urea (82.2 g, 1.37 mol), introducing cold water into a condenser pipe, connecting an ammonia gas absorption device thereon, heating and stirring, slowly heating the mixture to 140 ℃, keeping the temperature for reaction for 11h, and removing the generated water and ammonia gas to obtain DMF slurry of sodium cyanate for later use. Another chloropropene (110.0 g, 1.44 mol) was taken and transferred into a liquid metering pump bottle. Starting a temperature control system, respectively adjusting a slurry metering pump and a liquid metering pump, and controlling the molar ratio of the introduced DMF slurry of sodium cyanate to chloropropene to be 1:1.05, and feeding the mixture into a tubular reactor 1 with axial stirring, controlling the temperature at 40 ℃ and keeping the residence time at 45s. The reaction liquid flows into a tubular reactor 2 with axial stirring, the temperature is controlled to be 170 ℃, the residence time is 35s, after filtering and desalting, the reaction liquid flows into a rectifying still, and 102.3g of triallyl isocyanurate with the content of 98.7 percent and the total yield of 85.7 percent (calculated by chloropropene) is obtained by rectifying and purifying.
Example 2
A thermometer and a water separator were mounted on a 500 mL three-necked flask, and a condenser tube was mounted on the water separator. 160g of N, N-Dimethylformamide (DMF) and Na were sequentially added 2 CO 3 (69.3 g, 0.65 mol) and urea (78.5 g, 1.31 mol), introducing cold water into a condenser pipe, connecting an ammonia gas absorption device to the condenser pipe, heating and stirring, slowly heating the mixture to 145 ℃, keeping the temperature for reaction for 10 hours, and removing the generated water and ammonia gas to obtain the DMF slurry of sodium cyanate for later use.Another chloropropene (110.0 g, 1.44 mol) was taken and transferred into a liquid metering pump bottle. Starting a temperature control system, respectively adjusting a slurry metering pump and a liquid metering pump, and controlling the molar ratio of the introduced DMF slurry of sodium cyanate to chloropropene to be 1:1.10, the reaction mixture enters a tubular reactor 1 with axial stirring, the temperature is controlled to be 45 ℃, and the retention time is 30s. The reaction liquid flows into a tubular reactor 2 with axial stirring, the temperature is controlled to be 175 ℃, the retention time is 25s, after filtering and desalting, the reaction liquid flows into a rectifying still, and 102.9g of triallyl isocyanurate with the content of 99.1 percent and the total yield of 86.2 percent (calculated by chloropropene) is obtained by rectifying and purifying.
Example 3
A thermometer and a water separator are arranged on a 500 mL three-necked bottle, and a condenser pipe is arranged on the water separator. Adding 200g of N, N-Dimethylformamide (DMF) and Na in sequence 2 CO 3 (72.9 g, 0.69 mol) and urea (80.5 g, 1.34 mol), introducing cold water into a condenser pipe, connecting an ammonia gas absorption device to the condenser pipe, heating and stirring, slowly heating the mixture to 143 ℃, keeping the temperature for reaction for 10.5h, and removing generated water and ammonia gas to obtain the DMF slurry of sodium cyanate for later use. Another chloropropene (110.0 g, 1.44 mol) was taken and transferred into a liquid metering pump bottle. Starting a temperature control system, respectively adjusting a slurry metering pump and a liquid metering pump, and controlling the molar ratio of the introduced DMF slurry of the sodium cyanate to the chloropropene to be 1:1.07, and feeding the mixture into a tubular reactor 1 with axial stirring, controlling the temperature at 43 ℃ and the retention time at 40s. The reaction liquid flows into a tubular reactor 2 with axial stirring, the temperature is controlled to be 173 ℃, the residence time is 30s, after filtering and desalting, the reaction liquid flows into a rectifying still, and the triallyl isocyanurate is obtained by rectifying and purifying, wherein the content of the triallyl isocyanurate is 101.1g, the triallyl isocyanurate is 98.5 percent, and the total yield is 84.7 percent (calculated by chloropropene).
Example 4
A thermometer and a water separator are arranged on a 500 mL three-necked bottle, and a spherical condenser tube is arranged on the water separator. 215g of N, N-Dimethylformamide (DMF) and Na were sequentially added 2 CO 3 (71.0 g, 0.67 mol) and urea (79.5 g, 1.32 mol), introducing cold water into a condenser pipe, connecting an ammonia gas absorption device to the condenser pipe, heating and stirring, slowly heating the mixture to the temperature ofAnd (3) keeping the temperature at 142 ℃ for reaction for 10.7 hours, and removing the generated water and ammonia gas to obtain the DMF slurry of sodium cyanate for later use. Another chloropropene (110.0 g, 1.44 mol) was taken and transferred into a liquid metering pump bottle. Starting a temperature control system, respectively adjusting a slurry metering pump and a liquid metering pump, and controlling the molar ratio of the introduced DMF slurry of sodium cyanate to chloropropene to be 1:1.09, into a tubular reactor 1 with axial stirring, the temperature being controlled at 42 ℃ and the residence time being 41s. The reaction liquid flows into a tubular reactor 2 with axial stirring, the temperature is controlled to be 174 ℃, the retention time is 28s, after filtering and desalting, the reaction liquid flows into a rectifying still, and the triallyl isocyanurate is obtained by rectifying and purifying, wherein the content of the triallyl isocyanurate is 103.3g, the triallyl isocyanurate content is 98.9 percent, and the total yield is 86.5 percent (calculated by chloropropene).
Example 5
A thermometer and a water separator are arranged on a 500 mL three-necked bottle, and a spherical condenser pipe is arranged on the water separator. 190g of N, N-Dimethylformamide (DMF) and Na were sequentially added 2 CO 3 (74.2 g, 0.70 mol) and urea (81.7 g, 1.36 mol), introducing cold water into a condenser pipe, connecting an ammonia gas absorption device on the condenser pipe, heating and stirring, slowly heating the mixture to 144 ℃, keeping the temperature for reaction for 10.3h, and removing generated water and ammonia gas to obtain the DMF slurry of sodium cyanate for later use. Another chloropropene (110.0 g, 1.44 mol) was taken and transferred into a liquid metering pump bottle. Starting a temperature control system, respectively adjusting a slurry metering pump and a liquid metering pump, and controlling the molar ratio of the introduced DMF slurry of sodium cyanate to chloropropene to be 1:1.06, the reaction mixture is introduced into a tubular reactor 1 with axial stirring, the temperature is controlled at 44 ℃ and the residence time is 43s. The reaction liquid flows into a tubular reactor 2 with axial stirring, the temperature is controlled at 172 ℃, the residence time is 32s, after filtering and desalting, the reaction liquid flows into a rectifying still, and the triallyl isocyanurate is obtained by rectifying and purifying, wherein the content of the triallyl isocyanurate is 101.8g, the triallyl isocyanurate content is 98.9%, and the total yield is 85.3% (calculated by chloropropene).
The above description is only a preferred embodiment of the present invention, and the scope of the present invention is not limited to the above-described examples. All technical schemes belonging to the idea of the invention belong to the protection scope of the invention. It should be noted that modifications and embellishments within the scope of the invention may be made by those skilled in the art without departing from the principle of the invention, and such modifications and embellishments should also be considered as within the scope of the invention.
Claims (6)
1. The synthesis method of triallyl isocyanurate is characterized by comprising the following steps: (1) synthesis of sodium cyanate: sequentially adding DMF, urea and sodium carbonate into a reaction kettle, heating to 140-145 ℃, preserving heat for 10-11 h, deaminating and dehydrating to obtain DMF slurry of sodium cyanate for later use; (2) substitution reaction: respectively pumping the DMF slurry of sodium cyanate and chloropropene into a tubular reactor 1 with axial stirring by controlling the feeding speed of a slurry metering pump and a liquid metering pump to carry out substitution reaction, controlling the temperature of the tubular reactor 1 to be between 40 and 45 ℃ and keeping the material for 30 to 45 seconds, and then feeding the reaction liquid into a tubular reactor 2 with axial stirring; (3) cyclization reaction: controlling the temperature of the tubular reactor 2 to be 170-175 ℃, keeping the materials for 25-35 s, filtering and desalting the reaction liquid, then feeding the reaction liquid into a rectifying kettle, and carrying out negative pressure rectification and purification to obtain the triallyl isocyanurate.
2. The process according to claim 1, wherein the molar ratio of sodium carbonate to urea is 1:1.9 to 1:2.0.
3. the process according to claim 1, wherein the mass of DMF is 2 to 3 times that of urea.
4. The process according to claim 1, wherein the molar ratio of sodium cyanate to chloropropene is 1:1.05 to 1:1.10.
5. the process according to claim 1, wherein the temperature of the material in the tubular reactor 1 with axial stirring is controlled to 40 ℃ to 45 ℃ and the temperature in the tubular reactor 2 with axial stirring is controlled to 170 ℃ to 175 ℃.
6. The process for synthesizing triallyl isocyanurate according to claim 1, wherein the residence time of the materials in the tubular reactor 1 with axial stirring is 30s to 45s, and the residence time in the tubular reactor 2 with axial stirring is 25s to 35s.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2866801A (en) * | 1955-12-27 | 1958-12-30 | Ethyl Corp | Process for the production of organic isocyanates |
| JP2000109314A (en) * | 1998-10-05 | 2000-04-18 | Nippon Kasei Chem Co Ltd | Production of alkali metallic cyanate and cyanuric acid derivative |
| CN101125832A (en) * | 2006-08-18 | 2008-02-20 | 德古萨股份公司 | Method for preparing triallyl isocyanurate |
| CN106810505A (en) * | 2017-03-02 | 2017-06-09 | 江苏华星新材料科技股份有限公司 | The technique that a kind of isocyanuric acid prepares Triallyl isocyanurate |
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- 2022-08-02 CN CN202210918788.9A patent/CN114989104B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2866801A (en) * | 1955-12-27 | 1958-12-30 | Ethyl Corp | Process for the production of organic isocyanates |
| JP2000109314A (en) * | 1998-10-05 | 2000-04-18 | Nippon Kasei Chem Co Ltd | Production of alkali metallic cyanate and cyanuric acid derivative |
| CN101125832A (en) * | 2006-08-18 | 2008-02-20 | 德古萨股份公司 | Method for preparing triallyl isocyanurate |
| CN106810505A (en) * | 2017-03-02 | 2017-06-09 | 江苏华星新材料科技股份有限公司 | The technique that a kind of isocyanuric acid prepares Triallyl isocyanurate |
Non-Patent Citations (1)
| Title |
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| 氰尿酸合成工艺研究进展;陈焕章 等;《应用化工》;20160531;第45卷(第5期);第953-957页 * |
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