CN114014811A - Preparation method of 1, 3-dimethylol-5, 5-dimethylhydantoin - Google Patents
Preparation method of 1, 3-dimethylol-5, 5-dimethylhydantoin Download PDFInfo
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- CN114014811A CN114014811A CN202111519127.0A CN202111519127A CN114014811A CN 114014811 A CN114014811 A CN 114014811A CN 202111519127 A CN202111519127 A CN 202111519127A CN 114014811 A CN114014811 A CN 114014811A
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- Prior art keywords
- dimethylhydantoin
- dimethylol
- reaction
- paraformaldehyde
- producing
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- WSDISUOETYTPRL-UHFFFAOYSA-N dmdm hydantoin Chemical compound CC1(C)N(CO)C(=O)N(CO)C1=O WSDISUOETYTPRL-UHFFFAOYSA-N 0.000 title claims abstract description 37
- 229940058012 1,3-dimethylol-5,5-dimethylhydantoin Drugs 0.000 title claims abstract description 33
- 238000002360 preparation method Methods 0.000 title claims abstract description 17
- 229930040373 Paraformaldehyde Natural products 0.000 claims abstract description 19
- 229920002866 paraformaldehyde Polymers 0.000 claims abstract description 19
- YIROYDNZEPTFOL-UHFFFAOYSA-N 5,5-Dimethylhydantoin Chemical compound CC1(C)NC(=O)NC1=O YIROYDNZEPTFOL-UHFFFAOYSA-N 0.000 claims abstract description 17
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 17
- 238000000034 method Methods 0.000 claims abstract description 15
- 239000002994 raw material Substances 0.000 claims abstract description 14
- 239000003054 catalyst Substances 0.000 claims abstract description 12
- 238000004519 manufacturing process Methods 0.000 claims abstract description 10
- 239000002904 solvent Substances 0.000 claims abstract description 9
- 230000008569 process Effects 0.000 claims abstract description 7
- 230000009471 action Effects 0.000 claims abstract description 4
- 238000007031 hydroxymethylation reaction Methods 0.000 claims abstract description 4
- 238000006243 chemical reaction Methods 0.000 claims description 40
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical group [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 18
- 238000003756 stirring Methods 0.000 claims description 16
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 15
- 239000007864 aqueous solution Substances 0.000 claims description 12
- 239000012265 solid product Substances 0.000 claims description 7
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 6
- 239000012263 liquid product Substances 0.000 claims description 5
- 238000004821 distillation Methods 0.000 claims description 4
- 238000010438 heat treatment Methods 0.000 claims description 4
- 238000002156 mixing Methods 0.000 claims description 3
- 229910000029 sodium carbonate Inorganic materials 0.000 claims description 3
- 230000035484 reaction time Effects 0.000 claims description 2
- 239000007795 chemical reaction product Substances 0.000 claims 1
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 abstract description 15
- 238000003889 chemical engineering Methods 0.000 abstract description 6
- 239000008098 formaldehyde solution Substances 0.000 abstract description 6
- 239000002699 waste material Substances 0.000 abstract description 6
- 230000015572 biosynthetic process Effects 0.000 abstract description 3
- 239000002085 irritant Substances 0.000 abstract description 3
- 231100000021 irritant Toxicity 0.000 abstract description 3
- 238000003786 synthesis reaction Methods 0.000 abstract description 3
- 231100000331 toxic Toxicity 0.000 abstract description 3
- 230000002588 toxic effect Effects 0.000 abstract description 3
- 239000012847 fine chemical Substances 0.000 abstract description 2
- 239000000126 substance Substances 0.000 abstract 1
- 239000000047 product Substances 0.000 description 16
- 239000003755 preservative agent Substances 0.000 description 8
- 230000002335 preservative effect Effects 0.000 description 8
- 230000001954 sterilising effect Effects 0.000 description 7
- 238000001914 filtration Methods 0.000 description 6
- 238000001816 cooling Methods 0.000 description 5
- 239000012535 impurity Substances 0.000 description 5
- 238000000746 purification Methods 0.000 description 5
- 238000007086 side reaction Methods 0.000 description 5
- 238000013461 design Methods 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 239000003208 petroleum Substances 0.000 description 4
- 238000011160 research Methods 0.000 description 4
- 230000000844 anti-bacterial effect Effects 0.000 description 3
- 238000005580 one pot reaction Methods 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- 238000005536 corrosion prevention Methods 0.000 description 2
- 239000002537 cosmetic Substances 0.000 description 2
- 238000004659 sterilization and disinfection Methods 0.000 description 2
- 238000005292 vacuum distillation Methods 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 239000004480 active ingredient Substances 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 239000003242 anti bacterial agent Substances 0.000 description 1
- 230000002421 anti-septic effect Effects 0.000 description 1
- 239000003899 bactericide agent Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000012295 chemical reaction liquid Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 231100000614 poison Toxicity 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000009967 tasteless effect Effects 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
- 239000003440 toxic substance Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D233/00—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings
- C07D233/54—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings having two double bonds between ring members or between ring members and non-ring members
- C07D233/66—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings having two double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D233/72—Two oxygen atoms, e.g. hydantoin
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention belongs to the technical field of fine chemical engineering, and particularly relates to a preparation method of 1, 3-dimethylol-5, 5-dimethylhydantoin, which takes paraformaldehyde and 5, 5-dimethylhydantoin as raw materials, water as a solvent, and the 1, 3-dimethylol-5, 5-dimethylhydantoin is prepared through a hydroxymethylation reaction under the action of an alkaline catalyst. The invention provides a new synthesis process, formaldehyde is a toxic irritant substance, the process avoids using a formaldehyde solution, effectively improves the environment of a production workshop, improves the production safety, does not discharge three wastes, and is a green synthesis process.
Description
Technical Field
The invention belongs to the technical field of fine chemical engineering, and particularly relates to a preparation method of 1, 3-dimethylol-5, 5-dimethylhydantoin.
Background
The 1, 3-dimethylol-5, 5-dimethylhydantoin (DMDMDMH for English abbreviation) as a sterilizing preservative is firstly a bactericide researched and developed by the American Longsha company, and the active ingredient of the 1, 3-dimethylol-5, 5-dimethylhydantoin is a colorless and tasteless solid which is easily soluble in water and belongs to a high-efficiency broad-spectrum type preservative and antibacterial agent. In the industries of cosmetics, washing products, coatings and the like registered by EPA and EU, the preservative is mainly applied to the corrosion prevention of cosmetics, washing products and textiles at home and can also be widely applied to the corrosion prevention of industrial products. The product is sold mainly as 55% water solution, and is convenient to use. The antiseptic dmdmdmh has two sterilization mechanisms: firstly, free formaldehyde is slowly released to play a role in bacteriostasis and sterilization; secondly, N-hydroxymethyl in the preservative is a bactericidal group and can play a bactericidal role.
The synthesis of 1, 3-dimethylol-5, 5-dimethylhydantoin has been reported in the literature. For example, 5-dimethylhydantoin is reacted with an aqueous formaldehyde solution to produce an aqueous solution of 1, 3-dimethylol 5, 5-dimethylhydantoin, and the aqueous solution is distilled under reduced pressure to obtain a solid product. The process adopts formaldehyde solution as a raw material, and the formaldehyde is volatile, belongs to toxic substances, has strict requirements on the production process and ensures the production safety. And patent US4908456 mentions that the preparation method adopts 5, 5-dimethylhydantoin and paraformaldehyde in a heterogeneous reaction system, and the post-treatment of the process is more complex, so that a pure product is not easy to obtain and the cost is higher.
Disclosure of Invention
In order to solve the technical problems, the invention provides a preparation method of 1, 3-dimethylol-5, 5-dimethylhydantoin, which can not only avoid using a formaldehyde solution and improve the production safety, but also produce products by a simple process.
The invention is realized by the following technical scheme.
A preparation method of 1, 3-dimethylol-5, 5-dimethylhydantoin comprises the following steps:
paraformaldehyde and 5, 5-dimethylhydantoin are used as raw materials, water is used as a solvent, and 1, 3-dimethylol-5, 5-dimethylhydantoin is prepared through a hydroxymethylation reaction under the action of an alkaline catalyst.
Preferably, the basic catalyst is sodium hydroxide, potassium hydroxide or sodium carbonate.
Preferably, the mass ratio of the paraformaldehyde to the basic catalyst is 144-189: 1.
preferably, the mass ratio of the paraformaldehyde to the 5, 5-dimethylhydantoin is 1: 2-4.6.
Preferably, the reaction temperature is 50-95 ℃.
Preferably, the reaction time is 1-5 h.
Preferably, the raw materials are added in the following modes: mixing paraformaldehyde and an alkaline catalyst, adding water, heating, stirring, adding 5, 5-dimethylhydantoin, and continuously stirring for reaction.
Preferably, after the reaction is finished, the temperature is reduced, and the 1, 3-dimethylol-5, 5-dimethylhydantoin aqueous solution is obtained through filtration, and the aqueous solution can be prepared into a liquid product.
Preferably, after the reaction is finished, a solid product is obtained by adopting a reduced pressure distillation mode.
Compared with the prior art, the invention has the following beneficial effects:
(1) according to the invention, paraformaldehyde and 5, 5-dimethylhydantoin are used as raw materials, toxic and irritant raw material formaldehyde solution is avoided, the product is successfully prepared, and after the reaction is finished and filtered, the prepared reaction liquid meets the product standard, and can be directly sold as a liquid product without generating three wastes, or after the reaction is finished, a vacuum distillation method is adopted to prepare a solid product, so that the yield is high.
(2) In the patent in the background art, the reaction is carried out in a heterogeneous reaction system, because no solvent is added, the reaction can be promoted only by raising the temperature to enable the raw materials to reach a molten state in the reaction process, and the rise of the reaction temperature induces the occurrence of side reactions, so that the impurities in the reaction system are increased, and the purification of the product is difficult; the invention takes water as solvent, can ensure the reaction to be carried out at lower reaction temperature, has no side reaction in the system, has less impurities, simplifies the purification process, ensures that the whole preparation process is simple and convenient, can be synthesized by a one-pot method, is environment-friendly and has no three wastes.
Detailed Description
In order to make the technical solutions of the present invention better understood and enable those skilled in the art to practice the present invention, the following examples and data are provided for further illustration, but the examples are not intended to limit the present invention.
The experimental methods and the detection methods described in the following examples are all conventional methods unless otherwise specified; the reagents and materials are commercially available, unless otherwise specified.
The application provides a preparation method of 1, 3-dimethylol-5, 5-dimethylhydantoin, which comprises the following steps:
paraformaldehyde and 5, 5-dimethylhydantoin are used as raw materials, water is used as a solvent, and 1, 3-dimethylol-5, 5-dimethylhydantoin is prepared through a hydroxymethylation reaction under the action of an alkaline catalyst.
The alkaline catalyst is sodium hydroxide, potassium hydroxide or sodium carbonate, and the raw materials are added in the following modes: mixing paraformaldehyde and an alkaline catalyst, adding water, heating, stirring, then adding 5, 5-dimethylhydantoin, continuously stirring for reaction, cooling after the reaction is finished, and filtering to obtain an aqueous solution of 1, 3-dimethylol-5, 5-dimethylhydantoin, wherein the aqueous solution can be prepared into a liquid product. Or after the reaction is finished, processing the mixture in a reduced pressure distillation mode to obtain a solid product.
The invention takes water as solvent, can ensure the reaction to be carried out at lower reaction temperature, has no side reaction in the system, has less impurities, simplifies the purification process, ensures that the whole preparation process is simple and convenient, can be synthesized by a one-pot method, is environment-friendly and has no three wastes.
The following describes the above details in examples 1 to 5.
Example 1
A preparation method of 1, 3-dimethylol-5, 5-dimethylhydantoin comprises the following steps:
adding 170g of paraformaldehyde and 0.9g of potassium hydroxide into a reaction kettle, adding 465g of water, setting the temperature to be 70 ℃, and starting to heat and stir; adding 380g of 5, 5-dimethylhydantoin after 15 minutes, continuing stirring for 150 minutes, and then cooling; filtering to obtain the 1, 3-dihydroxymethyl-5, 5-dimethylhydantoin aqueous solution product which meets the requirements of the enterprise standard Q/SH 221-jar 2021 sterilizing preservative (DMDMDMH) Huake-282 of the petroleum chemical engineering research and design institute of Shaanxi province.
Example 2
A preparation method of 1, 3-dimethylol-5, 5-dimethylhydantoin comprises the following steps:
adding 150g of paraformaldehyde and 0.9g of sodium hydroxide into a reaction kettle, then adding 440g of water, starting to heat and stir, and setting the temperature to 80 ℃; after 15 minutes, adding 360g of 5, 5-dimethylhydantoin, continuing stirring for 90 minutes, and then cooling; filtering to obtain the 1, 3-dihydroxymethyl-5, 5-dimethylhydantoin aqueous solution product which meets the requirements of the enterprise standard Q/SH 221-jar 2021 sterilizing preservative (DMDMDMH) Huake-282 of the petroleum chemical engineering research and design institute of Shaanxi province.
Example 3
A preparation method of 1, 3-dimethylol-5, 5-dimethylhydantoin comprises the following steps:
adding 125g of paraformaldehyde and 0.8g of potassium hydroxide into a reaction kettle, then adding 450g of water, starting to heat and stir, and setting the temperature to be 75 ℃; after 10 minutes, adding 360g of 5, 5-dimethylhydantoin, continuing stirring for 100 minutes, and then cooling; filtering to obtain the 1, 3-dihydroxymethyl-5, 5-dimethylhydantoin aqueous solution product which meets the requirements of the enterprise standard Q/SH 221-jar 2021 sterilizing preservative (DMDMDMH) Huake-282 of the petroleum chemical engineering research and design institute of Shaanxi province.
Example 4
A preparation method of 1, 3-dimethylol-5, 5-dimethylhydantoin comprises the following steps:
adding 125g of paraformaldehyde and 0.8g of sodium hydroxide into a reaction kettle, then adding 450g of water, starting to heat and stir, and setting the temperature to 80 ℃; adding 320g of 5, 5-dimethylhydantoin after 15 minutes, continuing stirring for 120 minutes, and then cooling; filtering to obtain the 1, 3-dihydroxymethyl-5, 5-dimethylhydantoin aqueous solution product which meets the requirements of the enterprise standard Q/SH 221-jar 2021 sterilizing preservative (DMDMDMH) Huake-282 of the petroleum chemical engineering research and design institute of Shaanxi province.
Example 5
A preparation method of 1, 3-dimethylol-5, 5-dimethylhydantoin comprises the following steps:
adding 130g of paraformaldehyde and 0.9g of sodium hydroxide into a reaction kettle, then adding 430g of water, starting heating and stirring, and setting the temperature to 65 ℃; after 10 minutes, 290g of 5, 5-dimethylhydantoin was added, stirring was continued for 120 minutes, and then distillation under reduced pressure was carried out to obtain a solid product of 1, 3-dimethylol-5, 5-dimethylhydantoin with a yield of 95.6%.
Therefore, the invention uses paraformaldehyde and 5, 5-dimethylhydantoin as raw materials, avoids using toxic and irritant raw material formaldehyde solution, successfully prepares the product, and after the reaction is finished and filtered, the prepared reaction solution meets the product standard, can be directly sold as a liquid product without generating three wastes, or after the reaction is finished, a vacuum distillation method is adopted to prepare a solid product, and the yield is high. In the patent in the background art, the reaction is carried out in a heterogeneous reaction system, because no solvent is added, the reaction can be promoted only by raising the temperature to enable the raw materials to reach a molten state in the reaction process, and the rise of the reaction temperature induces the occurrence of side reactions, so that the impurities in the reaction system are increased, and the purification of the product is difficult; the invention takes water as solvent, can ensure the reaction to be carried out at lower reaction temperature, has no side reaction in the system, has less impurities, simplifies the purification process, ensures that the whole preparation process is simple and convenient, can be synthesized by a one-pot method, is environment-friendly and has no three wastes.
It should be noted that, when the present invention relates to a numerical range, it should be understood that two endpoints of each numerical range and any value between the two endpoints can be selected, and since the steps and methods adopted are the same as those in the embodiment, in order to prevent redundancy, the present invention describes a preferred embodiment. While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, it is intended that such changes and modifications be included within the scope of the appended claims and their equivalents.
Claims (9)
1. The preparation method of the 1, 3-dimethylol-5, 5-dimethylhydantoin is characterized by comprising the following steps:
paraformaldehyde and 5, 5-dimethylhydantoin are used as raw materials, water is used as a solvent, and 1, 3-dimethylol-5, 5-dimethylhydantoin is prepared through a hydroxymethylation reaction under the action of an alkaline catalyst.
2. The method for producing 1, 3-dimethylol-5, 5-dimethylhydantoin according to claim 1, wherein the basic catalyst is sodium hydroxide, potassium hydroxide or sodium carbonate.
3. The method for preparing 1, 3-dimethylol-5, 5-dimethylhydantoin according to claim 1, wherein the mass ratio of paraformaldehyde to basic catalyst is 144-189: 1.
4. the method for producing 1, 3-dimethylol-5, 5-dimethylhydantoin according to claim 1, wherein the mass ratio of paraformaldehyde to 5, 5-dimethylhydantoin is 1:2 to 4.6.
5. The method for producing 1, 3-dimethylol-5, 5-dimethylhydantoin according to claim 1, wherein the reaction temperature is 50 to 95 ℃.
6. The method for producing 1, 3-dimethylol-5, 5-dimethylhydantoin according to claim 1, wherein the reaction time is 1 to 5 hours.
7. The method for producing 1, 3-dimethylol-5, 5-dimethylhydantoin according to claim 1, wherein the raw materials are added in the following manner: mixing paraformaldehyde and an alkaline catalyst, adding water, heating, stirring, adding 5, 5-dimethylhydantoin, and continuously stirring for reaction.
8. The method for preparing 1, 3-dimethylol-5, 5-dimethylhydantoin according to claim 1, wherein after the reaction is finished, the temperature is reduced, and the reaction product is filtered to obtain an aqueous solution of 1,3 dimethylol-5, 5-dimethylhydantoin, and the aqueous solution can be prepared into a liquid product.
9. The process for producing 1, 3-dimethylol-5, 5-dimethylhydantoin according to claim 1, wherein after completion of the reaction, a solid product is obtained by distillation under reduced pressure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111519127.0A CN114014811A (en) | 2021-12-13 | 2021-12-13 | Preparation method of 1, 3-dimethylol-5, 5-dimethylhydantoin |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111519127.0A CN114014811A (en) | 2021-12-13 | 2021-12-13 | Preparation method of 1, 3-dimethylol-5, 5-dimethylhydantoin |
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| CN114014811A true CN114014811A (en) | 2022-02-08 |
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| CN202111519127.0A Pending CN114014811A (en) | 2021-12-13 | 2021-12-13 | Preparation method of 1, 3-dimethylol-5, 5-dimethylhydantoin |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04360873A (en) * | 1991-06-06 | 1992-12-14 | Mitsui Toatsu Chem Inc | Production of dimethylolhdantoin compound |
| US5252744A (en) * | 1992-05-21 | 1993-10-12 | Lonza Inc. | Process for preparing methylolhydantoins |
| CN109503493A (en) * | 2018-12-23 | 2019-03-22 | 陕西省石油化工研究设计院 | A kind of preparation method of -5,5 Dimethyl Hydan DMDMH of 1,3 dihydroxymethyl of anti-freeze type |
-
2021
- 2021-12-13 CN CN202111519127.0A patent/CN114014811A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04360873A (en) * | 1991-06-06 | 1992-12-14 | Mitsui Toatsu Chem Inc | Production of dimethylolhdantoin compound |
| US5252744A (en) * | 1992-05-21 | 1993-10-12 | Lonza Inc. | Process for preparing methylolhydantoins |
| CN109503493A (en) * | 2018-12-23 | 2019-03-22 | 陕西省石油化工研究设计院 | A kind of preparation method of -5,5 Dimethyl Hydan DMDMH of 1,3 dihydroxymethyl of anti-freeze type |
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Address after: No.61 Xiyan Road, Yanta District, Xi'an City, Shaanxi Province, 710054 Applicant after: Shaanxi Chemical Research Institute Co.,Ltd. Address before: No.61 Xiyan Road, Yanta District, Xi'an City, Shaanxi Province, 710054 Applicant before: SHAANXI RESEARCH DESIGN INSTITUTE OF PETROLEUM CHEMICAL INDUSTRY |