CN112500360A - Safe and environment-friendly cyromazine synthesis method - Google Patents
Safe and environment-friendly cyromazine synthesis method Download PDFInfo
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- CN112500360A CN112500360A CN202011501444.5A CN202011501444A CN112500360A CN 112500360 A CN112500360 A CN 112500360A CN 202011501444 A CN202011501444 A CN 202011501444A CN 112500360 A CN112500360 A CN 112500360A
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- 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
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- C07D251/54—Three nitrogen atoms
- C07D251/70—Other substituted melamines
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Abstract
The invention discloses a safe and environment-friendly cyromazine synthesis method, which comprises the steps of taking cyanuric chloride as a raw material, firstly reacting with ammonium salt under the action of a catalyst to obtain an intermediate 2-chloro-4, 6-diamino-1, 3, 5-triazine, and then reacting with cyclopropylamine to obtain cyromazine. The method of the invention adopts ammonium salt as the source of ammonia, can effectively improve the yield of cyromazine under the action of the catalyst, can avoid using highly polluted, flammable and explosive ammonia water or liquid ammonia, and can reduce the ammonia nitrogen value in the wastewater, reduce pollution from the source and improve the process safety because the using amount of the ammonium salt is greatly reduced; and the treatment difficulty and treatment cost of the wastewater can be reduced.
Description
Technical Field
The invention relates to the field of organic synthesis, in particular to a safe and environment-friendly cyromazine synthesis method.
Background
Cyromazine, also known as cyromazine, a highly effective insect growth inhibitor, is widely used as a feed additive in animal feed, in animal husbandry and livestock breeding to control all flies that threaten intensive animal farms, including: housefly, yellow-belly toilet fly, etc., and can control fleas and prevent larvas of green fly on sheep body.
The domestic production method of cyromazine mainly adopts cyanuric chloride as raw material, firstly reacts with concentrated ammonia water or liquid ammonia (organic solvent is medium), and then reacts with cyclopropylamine to obtain cyromazine; it has also been reported in the literature to react with cyclopropylamine first, followed by ammonia or liquid ammonia. For example, the chinese patent document discloses "a method for preparing cyromazine", whose publication No. CN108084102A, comprising the following steps: 1) under the stirring condition, dissolving cyanuric chloride in an organic solvent at 0-5 ℃, then dropwise adding industrial ammonia water, heating to 40-45 ℃, keeping the temperature for reaction for 5-6.5 h to obtain a reaction solution, separating out the solvent, adding purified water into the remaining solution, stirring for 1-1.5 h, cooling to room temperature, carrying out suction filtration, washing with water, and drying to obtain an intermediate, wherein the intermediate is 2-chloro-4.6-diamino-1.3.5-triazine; 2) adding the intermediate prepared in the step 1) into purified water at room temperature, adding cyclopropylamine, heating to 90-95 ℃, dropwise adding an acid-binding agent, and adjusting the pH to 7.5-8.5; then reacting for 3.5-4.5 h at the temperature of 98-100 ℃, decoloring and filtering to obtain a reaction solution; and cooling to 40-50 ℃, crystallizing for 1-2 h, continuously cooling to-5-0 ℃, performing suction filtration, washing with water, and drying to obtain cyromazine.
No matter which production process is adopted, concentrated ammonia water or liquid ammonia is needed in the existing production method, the using amount is greatly excessive, and redundant ammonia water and liquid ammonia enter wastewater, so that the ammonia nitrogen value of the wastewater is extremely high, the biochemical treatment difficulty is high, and the cost is high. In addition, high-concentration ammonia water and liquid ammonia have great potential safety hazards, once leakage occurs, immeasurable consequences can be caused, various pollution can be caused to soil, atmosphere and water, and the volatilized ammonia has flammability and toxicity and has potential hazards of explosion and poisoning. Therefore, the method for producing cyromazine has the defects of large waste water amount, serious pollution, low safety, high requirement on equipment and the like, and causes high production cost, low economic benefit of enterprises and the like.
Disclosure of Invention
The invention provides a safe and environment-friendly cyromazine synthesis method, aiming at overcoming the problems that the existing cyromazine synthesis method needs to use concentrated ammonia water or liquid ammonia, the using amount is greatly excessive, the redundant ammonia water and ammonia gas volatilized by the liquid ammonia have flammability and toxicity, potential hazards of explosion and poisoning exist, and the ammonia nitrogen value of wastewater is extremely high due to entering of wastewater, the biochemical treatment difficulty is high, and the cost is high; and the treatment difficulty and treatment cost of the wastewater can be reduced.
In order to achieve the purpose, the invention adopts the following technical scheme:
a safe and environment-friendly cyromazine synthesis method is characterized by comprising the following synthesis steps:
the method takes cyanuric chloride as a raw material, firstly reacts with ammonium salt under the action of a catalyst to obtain an intermediate 2-chloro-4, 6-diamino-1, 3, 5-triazine, and then reacts with cyclopropylamine to obtain cyromazine. By adopting the method, the yield of the cyromazine can be effectively improved, the yield can reach more than 95 percent, the ammonium salt is used as the source of ammonia, the use of highly-polluted, inflammable and explosive ammonia water or liquid ammonia can be avoided, and simultaneously, as the using amount of the ammonium salt is greatly reduced, the ammonia nitrogen value in the wastewater can be reduced, the pollution is reduced from the source, and the process safety is improved; and the treatment difficulty and treatment cost of the wastewater can be reduced.
Preferably, the ammonium salt in step (1) is one selected from ammonium salts such as ammonium chloride, ammonium bromide, ammonium fluoride, ammonium iodide, ammonium sulfate, ammonium bisulfate, ammonium nitrate, ammonium carbonate, ammonium bicarbonate, ammonium phosphate, ammonium dihydrogen phosphate, and diammonium hydrogen phosphate.
Preferably, the molar ratio of the ammonium salt to the cyanuric chloride is 0.33-2: 1.
preferably, a catalyst is added in the step (1), and the catalyst is alumina or copper oxide. Under the catalytic action of the catalyst, the ammonium salt can effectively react with cyanuric chloride, and the product yield is ensured.
Preferably, the amount of the catalyst is 1-3% of the mass of the cyanuric chloride.
Preferably, the reaction in the step (1) is carried out in an aqueous solution, and the amount of the water is 2-10 times of the weight of the cyanuric chloride.
Preferably, the reaction temperature in the step (1) is 70-100 ℃, the reaction pH is 7-10, and the reaction time is 1-8 hours.
Preferably, the molar ratio of the amount of cyclopropylamine to the cyanuric chloride in step (2) is 1.0-2.0: 1.
preferably, the reaction temperature in the step (2) is 50-100 ℃, the reaction pH is 7-10, and the reaction time is 1-8 hours.
Therefore, the invention has the following beneficial effects:
(1) the yield of cyromazine is improved to more than 95 percent;
(2) the ammonium salt is used as the source of ammonia, so that high-pollution, flammable and explosive ammonia water or liquid ammonia can be avoided, and meanwhile, as the using amount of the ammonium salt is greatly reduced, the ammonia nitrogen value in the wastewater can be reduced, the pollution is reduced from the source, and the process safety is improved; and the treatment difficulty and treatment cost of the wastewater can be reduced.
Detailed Description
The invention is further described with reference to specific embodiments.
In the present invention, unless otherwise specified, all the raw materials and equipment used are commercially available or commonly used in the art, and the methods in the examples are conventional in the art unless otherwise specified.
Example 1:
(1) adding 200g of cyanuric chloride, 69.61g of ammonium chloride, 4g of alumina and 1200g of water into a 3000ml reaction bottle, heating to 85 ℃, preserving heat for reacting for 6 hours, and adjusting the pH to 9.2 by using 30 wt% of sodium hydroxide solution during the heating and preserving heat;
(2) after the heat preservation is finished, the temperature is reduced to below 70 ℃, 74.30g of cyclopropylamine is added, then the temperature is re-heated to 85 ℃, the reaction is carried out for 6 hours, and during the period of temperature rise and heat preservation, the pH value is adjusted to 9.2 by using 30 wt% of sodium hydroxide solution. After the reaction is finished, the temperature is reduced to 25 ℃, the reaction product is filtered, then 400g of water is used for pulping and washing, and the reaction product is filtered and dried to obtain 172.21g of cyromazine, wherein the yield is 95.55 percent, and the purity is 98.8 percent by HPLC detection.
Example 2:
(1) adding 200g of cyanuric chloride, 52.11g of ammonium carbonate, 1g of copper oxide and 1200g of water into a 3000ml reaction bottle, heating to 90 ℃, preserving heat for reaction for 6 hours, and adjusting the pH to 9.0 by using 30 wt% of sodium hydroxide solution during the period of temperature rise and preservation;
(2) after the heat preservation is finished, the temperature is reduced to below 70 ℃, 74.30g of cyclopropylamine is added, then the temperature is re-heated to 90 ℃, the reaction is carried out for 6 hours, and during the period of temperature rise and heat preservation, the pH value is adjusted to 9.0 by using 30 wt% of sodium hydroxide solution. After the reaction is finished, the temperature is reduced to 25 ℃, the reaction product is filtered, then 400g of water is used for pulping and washing, and the reaction product is filtered and dried to obtain 172.66g of cyromazine, wherein the yield is 95.80 percent, and the purity is 98.1 percent by HPLC detection.
Example 3:
(1) adding 200g of cyanuric chloride, 102.89g of ammonium bicarbonate, 6g of alumina and 1200g of water into a 3000ml reaction bottle, heating to 85 ℃, preserving heat for reacting for 6 hours, and adjusting the pH to 9.5 by using 30 wt% of sodium hydroxide solution during the heating and preserving heat;
(2) after the heat preservation is finished, the temperature is reduced to below 70 ℃, 74.30g of cyclopropylamine is added, then the temperature is re-heated to 85 ℃, the reaction is carried out for 6 hours, and during the period of temperature rise and heat preservation, the pH value is adjusted to 9.5 by using 30 wt% of sodium hydroxide solution. After the reaction is finished, the temperature is reduced to 30 ℃, the reaction product is filtered, then 400g of water is used for pulping and washing, and the reaction product is filtered and dried to obtain 173.69g of cyromazine, wherein the yield is 96.37 percent, and the purity is 98.2 percent by HPLC detection.
Example 4:
(1) adding 200g of cyanuric chloride, 69.61g of ammonium chloride, 4g of alumina and 800g of water into a 3000ml reaction bottle, heating to 100 ℃, preserving heat for reacting for 4 hours, and adjusting the pH to 8.5 by using 30 wt% of sodium hydroxide solution during the heating and preserving heat;
(2) after the heat preservation is finished, the temperature is reduced to below 70 ℃, 74.30g of cyclopropylamine is added, then the temperature is re-heated to 100 ℃, the reaction is carried out for 4 hours, and during the period of temperature rise and heat preservation, the pH value is adjusted to 8.5 by using 30 wt% of sodium hydroxide solution. After the reaction is finished, the temperature is reduced to 30 ℃, the reaction product is filtered, then 400g of water is used for pulping and washing, and the reaction product is filtered and dried to obtain 172.28g of cyromazine with yield of 95.59% and purity of 98.6% by HPLC detection.
Example 5:
(1) adding 200g of cyanuric chloride, 69.61g of ammonium chloride, 4g of alumina and 800g of water into a 3000ml reaction bottle, heating to 70 ℃, preserving heat for reacting for 6 hours, and adjusting the pH to 7.2 by using 30 wt% of sodium hydroxide solution during the heating and preserving heat;
(2) after the heat preservation is finished, the temperature is reduced to below 70 ℃, 74.30g of cyclopropylamine is added, then the temperature is re-heated to 70 ℃, the reaction is kept for 4 hours, and during the period of temperature rise and heat preservation, the pH value is adjusted to 7.2 by using 30% sodium hydroxide solution. After the reaction is finished, the temperature is reduced to 25 ℃, the reaction product is filtered, then 400g of water is used for pulping and washing, and the reaction product is filtered and dried to obtain 165.67g of cyromazine, wherein the yield is 91.92 percent, and the purity is 98.5 percent by HPLC detection.
Example 6:
(1) adding 200g of cyanuric chloride, 69.61g of ammonium chloride, 5g of alumina and 800g of water into a 3000ml reaction bottle, heating to 90 ℃, preserving heat for reacting for 4 hours, and adjusting the pH to 10.0 by using 30 wt% of sodium hydroxide solution during the heating and preserving heat;
(2) after the heat preservation is finished, the temperature is reduced to below 70 ℃, 61.89g of cyclopropylamine is added, then the temperature is heated to 90 ℃ again, the reaction is kept for 4 hours, and during the period of temperature rise and heat preservation, the pH value is adjusted to 9.8 by using 30 wt% of sodium hydroxide solution. After the reaction is finished, the temperature is reduced to 25 ℃, the reaction product is filtered, then 400g of water is used for pulping and washing, and the reaction product is filtered and dried to obtain 171.13g of cyromazine, wherein the yield is 94.95 percent, and the purity is 98.7 percent by HPLC detection.
Example 7:
(1) adding 200g of cyanuric chloride, 69.61g of ammonium chloride, 4g of alumina and 800g of water into a 3000ml reaction bottle, heating to 85 ℃, preserving heat for reacting for 4 hours, and adjusting the pH to 9.3 by using 30 wt% of sodium hydroxide solution during the heating and preserving heat;
(2) after the heat preservation is finished, the temperature is reduced to below 70 ℃, 74.30g of cyclopropylamine is added, then the temperature is heated to 50 ℃ again, the reaction is kept for 6 hours, and during the period of temperature rise and heat preservation, the pH value is adjusted to 8.5 by using 30 wt% of sodium hydroxide solution. After the reaction is finished, the temperature is reduced to 25 ℃, the reaction product is filtered, then 400g of water is used for pulping and washing, and the reaction product is filtered and dried to obtain 173.22g of cyromazine with yield of 96.11% and purity of 98.1% by HPLC detection.
Example 8:
(1) adding 200g of cyanuric chloride, 69.61g of ammonium chloride, 4g of alumina and 800g of water into a 3000ml reaction bottle, heating to 85 ℃, preserving heat for reacting for 4 hours, and adjusting the pH to 9.5 by using 30 wt% of sodium hydroxide solution during the heating and preserving heat;
(2) after the heat preservation is finished, the temperature is reduced to below 70 ℃, 74.30g of cyclopropylamine is added, then the temperature is re-heated to 85 ℃, the reaction is carried out for 6 hours, and during the period of temperature rise and heat preservation, the pH value is adjusted to 8.0 by using 30 wt% of sodium hydroxide solution. After the reaction is finished, the temperature is reduced to 25 ℃, the reaction product is filtered, then 400g of water is used for pulping and washing, and the reaction product is filtered and dried to obtain 172.28g of cyromazine with yield of 95.59% and purity of 98.6% by HPLC detection.
Example 9:
(1) adding 200g of cyanuric chloride, 69.61g of ammonium chloride and 1200g of water into a 3000ml reaction bottle, heating to 85 ℃, keeping the temperature for reaction for 6 hours, and adjusting the pH to 9.2 by using 30 wt% of sodium hydroxide solution during the heating and keeping the temperature;
(2) after the heat preservation is finished, the temperature is reduced to below 70 ℃, 74.30g of cyclopropylamine is added, then the temperature is re-heated to 85 ℃, the reaction is carried out for 6 hours, and during the period of temperature rise and heat preservation, the pH value is adjusted to 9.2 by using 30 wt% of sodium hydroxide solution. After the reaction is finished, the temperature is reduced to 25 ℃, the reaction product is filtered, then 400g of water is used for pulping and washing, and the reaction product is filtered and dried to obtain 135.82g of cyromazine, wherein the yield is 75.36 percent, and the purity is 87.2 percent by HPLC detection.
Comparative example 1 (changing the reaction temperature in step (1)):
(1) adding 200g of cyanuric chloride, 69.61g of ammonium chloride, 4g of alumina and 1200g of water into a 3000ml reaction bottle, heating to 50 ℃, preserving heat for reacting for 6 hours, and adjusting the pH to 9.2 by using 30 wt% of sodium hydroxide solution during the heating and preserving heat;
(2) after the heat preservation, 74.30g of cyclopropylamine was added, then the mixture was reheated to 85 ℃ and the reaction was maintained for 6 hours, and during the heating and heat preservation, the pH was adjusted to 9.2 with 30 wt% sodium hydroxide solution. After the reaction is finished, the temperature is reduced to 25 ℃, the reaction product is filtered, then 400g of water is used for pulping and washing, and the reaction product is filtered and dried to obtain 151.30g of cyromazine with yield of 83.95% and purity of 98.1% by HPLC detection.
As can be seen from the above examples and comparative examples, the method and reaction conditions in examples 1 to 8 of the present invention for preparing cyromazine have high yield and purity, no catalyst is added in example 9, ammonium salt cannot effectively react with cyanuric chloride, and the yield and purity of the product are significantly reduced compared to those in example 1; in comparative example 2 where the reaction temperature in step (1) was changed to fall outside the range of the present invention, the yield of the final cyromazine was also reduced as compared with that in example 1, indicating that the reaction conditions had a large influence on the yield.
Claims (9)
1. A safe and environment-friendly cyromazine synthesis method is characterized in that cyanuric chloride is used as a raw material, and the synthesis steps are as follows:
2. the method for synthesizing environmentally friendly safe cyromazine according to claim 1, wherein the ammonium salt in step (1) is one selected from ammonium salts such as ammonium chloride, ammonium bromide, ammonium fluoride, ammonium iodide, ammonium sulfate, ammonium bisulfate, ammonium nitrate, ammonium carbonate, ammonium bicarbonate, ammonium phosphate, ammonium dihydrogen phosphate, and diammonium hydrogen phosphate.
3. The method for synthesizing safe and environment-friendly cyromazine according to claim 1 or 2, wherein the molar ratio of the ammonium salt to the cyanuric chloride is 0.33-2: 1.
4. the method for synthesizing the safe and environment-friendly cyromazine according to claim 1, wherein a catalyst is added in the step (1), and the catalyst is aluminum oxide or copper oxide.
5. The method for synthesizing safe and environment-friendly cyromazine according to claim 1 or 4, wherein the amount of the catalyst is 1-3% of the mass of cyanuric chloride.
6. The method for synthesizing the safe and environment-friendly cyromazine according to claim 1, wherein the reaction in the step (1) is carried out in an aqueous solution, and the amount of water is 2-10 times of the weight of cyanuric chloride.
7. The method for synthesizing the safe and environment-friendly cyromazine according to claim 1, wherein the reaction temperature in the step (1) is 70-100 ℃, the reaction pH is 7-10, and the reaction time is 1-8 hours.
8. The method for synthesizing safe and environment-friendly cyromazine according to claim 1, wherein the molar ratio of the amount of cyclopropylamine to the cyanuric chloride in step (2) is 1.0-2.0: 1.
9. the method for synthesizing the safe and environment-friendly cyromazine according to claim 1, wherein the reaction temperature in the step (2) is 50 to 100 ℃, the reaction pH is 7 to 10, and the reaction time is 1 to 8 hours.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115181071A (en) * | 2022-07-14 | 2022-10-14 | 山东道可化学有限公司 | Preparation method of cyromazine |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1202487A (en) * | 1997-06-18 | 1998-12-23 | 吉林化学工业公司江南设计研究院 | Two-step process for synthesizing anabasine |
| CN1356039A (en) * | 2001-11-09 | 2002-07-03 | 复旦大学 | Process for preparing insecticide 'Huanbingmazhen' |
| CN108084102A (en) * | 2017-11-27 | 2018-05-29 | 河南后羿制药有限公司 | A kind of preparation method of cyromazine |
-
2020
- 2020-12-17 CN CN202011501444.5A patent/CN112500360A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1202487A (en) * | 1997-06-18 | 1998-12-23 | 吉林化学工业公司江南设计研究院 | Two-step process for synthesizing anabasine |
| CN1356039A (en) * | 2001-11-09 | 2002-07-03 | 复旦大学 | Process for preparing insecticide 'Huanbingmazhen' |
| CN108084102A (en) * | 2017-11-27 | 2018-05-29 | 河南后羿制药有限公司 | A kind of preparation method of cyromazine |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115181071A (en) * | 2022-07-14 | 2022-10-14 | 山东道可化学有限公司 | Preparation method of cyromazine |
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