CN112300018B - Preparation method of N, N-dimethylamino ethyl acrylate - Google Patents
Preparation method of N, N-dimethylamino ethyl acrylate Download PDFInfo
- Publication number
- CN112300018B CN112300018B CN202011011149.1A CN202011011149A CN112300018B CN 112300018 B CN112300018 B CN 112300018B CN 202011011149 A CN202011011149 A CN 202011011149A CN 112300018 B CN112300018 B CN 112300018B
- Authority
- CN
- China
- Prior art keywords
- reaction
- ethyl acrylate
- dimethylamino ethyl
- dimethylamine
- preparation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C227/00—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton
- C07C227/04—Formation of amino groups in compounds containing carboxyl groups
- C07C227/10—Formation of amino groups in compounds containing carboxyl groups with simultaneously increasing the number of carbon atoms in the carbon skeleton
Abstract
The invention relates to a preparation method of N, N-dimethylamino ethyl acrylate. The preparation method of the N, N-dimethylamino ethyl acrylate has the advantages of short reaction route, high yield and purity and low safety risk.
Description
Technical Field
The invention relates to a preparation method of N, N-dimethylamino ethyl acrylate, belonging to the technical field of chemical synthesis.
Background
The N, N-dimethylamino ethyl acrylate is a quaternary ammonium acrylate with wide application, has the characteristics of ester, olefin and amine compounds, can be used for preparing key intermediates of bactericides (fluxapyroxad, dipheniamide, pyrromonamide and the like) namely 3-difluoromethyl-1-methylpyrazole-4-carboxylic acid, and can also be used for synthesizing anti-infective quinolone compounds (ciprofloxacin, moxifloxacin, levofloxacin, norfloxacin and the like). In recent years, N-dimethylaminoethyl acrylate has also been industrially used as a main raw material for specialty chemicals such as fiber treatment agents, paints, ion exchange resins, paper strength enhancers, and dye improvers.
At present, the method for synthesizing N, N-dimethylamino ethyl acrylate at home and abroad is mainly divided into the following steps:
(1) Aldol condensation process: ethyl acetate and ethyl formate are used as initial raw materials, and are reacted in the presence of sodium hydride to prepare ethyl formylacetate sodium salt, and then the ethyl formylacetate sodium salt is reacted with dimethylamine to obtain a target product. The sodium hydride involved in the method contains mineral oil, so that the purity of the product is influenced, and the potential safety hazard existing in the using process is high. In addition, the loss of ethyl formate and ethyl acetate is high in the using process, so that the control of VOCs is not facilitated, and the current increasingly strict ecological environment supervision requirements are not met.
(2) Diethyl sulfate method: n, N-dimethyl formamide is used as a raw material, is complexed with diethyl sulfate and then reacts with diethyl malonate to prepare the N, N-dimethylamino ethyl acrylate. The method uses N, N-dimethyl formamide, so that the waste water is difficult to degrade biochemically. In addition, the toxicity of diethyl sulfate is also high, which is not beneficial to occupational health protection of workshop staff, so that the method is not suitable for industrial production.
(3) Ethoxy acetylene method: n, N-dimethylformamide is taken as a raw material, and the N, N-dimethylformamide and ethoxyacetylene are catalyzed by borontrifluoride to obtain a target product by a one-step method. The related ethyoxylyne is short in market supply and expensive, and the recovery difficulty of the borontrifluoride catalyst is high, so that the comprehensive production cost is extremely high, and the value of industrial production is basically not available.
(4) Imine complexation method: the method is similar to a diethyl sulfate method, and comprises the steps of complexing N, N-dimethylformamide and dimethyl sulfate to prepare imine, reacting the imine with dimethylamine gas to generate dimethylamine-substituted imine, treating the imine by potassium tert-butoxide, and replacing the treated imine with ethyl acetate to obtain the N, N-dimethylamino ethyl acrylate. The method has long route and low atom utilization rate, and simultaneously, the dimethylamine gas is inconvenient to store and use, so the method has higher difficulty for industrial production.
(5) High pressure synthesis of carbon monoxide: carbon monoxide is used as a carbonyl source, and reacts with ethyl acetate in an autoclave under the action of sodium ethoxide to generate ethyl formylacetate sodium salt, and then the ethyl formylacetate sodium salt reacts with dimethylamine hydrochloride to prepare the target product. In view of the advantages of high atom utilization rate, high yield, cheap and easily available raw materials and the like, the method is a mainstream process for industrially producing the N, N-dimethylamino ethyl acrylate at present. However, the method involves a high-pressure reaction (above 2.2 MPa), and the raw material is colorless and tasteless highly toxic gas carbon monoxide, which can be evaluated as a major hazard source in the safety evaluation process of chemical enterprises, and the safety control cost in the actual production process is very high.
Chinese patent document CN109553543A (application number: 201711476368.5) discloses a synthetic method of N, N-dimethylamino ethyl acrylate, which comprises the following steps: ethyl acetate, carbon monoxide and dimethylamine are used as initial raw materials and react under the action of a solid base catalyst to generate a target product N, N-dimethylamino ethyl acrylate; the solid base catalyst is preferably a supported solid base catalyst. Although the method avoids the generation of intermediate products in the process, carbon monoxide is still used as a carbonyl source, the preparation of a specific catalyst is complicated, and an autoclave is also required for pressurization, so that great potential safety hazards and high cost are still caused in the actual production.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a preparation method of N, N-dimethylamino ethyl acrylate, which has the advantages of short reaction route, high yield and purity and low safety risk. The invention provides a technical scheme for solving the technical problems, which comprises the following steps: a preparation method of N, N-dimethylamino ethyl acrylate is characterized by comprising the following steps: formic acid, ethyl acetate and dimethylamine are heated to react to prepare N, N-dimethylamino ethyl acrylate and water, and the reaction formula is as follows:
the reaction temperature of the reaction is 120-150 ℃.
The reaction pressure of the reaction is 0.4MPa to 0.8MPa.
Preferably, the reaction temperature of the reaction is 125-130 ℃, and the reaction pressure is 0.5-0.6 MPa.
The reaction was maintained under pressure with a nitrogen blanket.
The dimethylamine is a dimethylamine aqueous solution with the concentration of 30 to 50 percent.
The molar weight ratio of the formic acid to the ethyl acetate to the dimethylamine is 1.4-1.6: 1-1.2.
Preferably, the molar ratio of formic acid, ethyl acetate and dimethylamine is 1.5: 1: 1.1.
The N, N-dimethylamino ethyl acrylate prepared by the reaction is frozen and dried to obtain a crude product of the N, N-dimethylamino ethyl acrylate with the water content less than or equal to 0.5 percent.
And (3) carrying out vacuum rectification on the crude product of the N, N-dimethylamino ethyl acrylate to obtain a finished product of the N, N-dimethylamino ethyl acrylate.
The vacuum degree of the invention during vacuum rectification is 0.095MPa, the temperature of the vacuum rectification can be properly improved along with the progress of the rectification, and the temperature of the distillate which begins to be discharged is 150 ℃.
The invention has the positive effects that:
(1) The preparation method of the N, N-dimethylamino ethyl acrylate takes formic acid, ethyl acetate and dimethylamine as raw materials, prepares the N, N-dimethylamino ethyl acrylate by a one-pot method, has short route, simple and easily obtained raw materials, high atom utilization rate, simple reaction system, good reaction conditions for reducing the labor intensity of workers, high yield, safety, controllability and high product purity, and is suitable for industrial large-scale production. The production cost can be as low as 1.2 ten thousand yuan/ton, and the gross profit can be 23000 ten thousand yuan per year according to the estimation of 3.5 ten thousand yuan/ton market price and the productivity of 10000 tons/year.
(2) The preparation method of the N, N-dimethylamino ethyl acrylate improves the carbon monoxide high-pressure synthesis method, does not need to use virulent gas carbon monoxide as a carbonyl source, uses formic acid to decompose the carbon monoxide to obtain carbon monoxide, continuously reacts and consumes the carbon monoxide generated by decomposition in a closed reaction device, and effectively avoids the use of high-pressure reaction and the virulent gas carbon monoxide, wherein the reaction pressure is controlled between 0.4MPa and 0.8MPa.
(3) The dimethylamine used in the reaction of the preparation method of the N, N-dimethylamino ethyl acrylate is dimethylamine aqueous solution, so that the defect of high dimethylamine gas storage cost is overcome, the operation is simple and convenient, the production cost is greatly reduced, the generation of intermediate products and impurities is avoided, and the gross profit in industrial production is greatly improved.
(4) According to the preparation method of the N, N-dimethylamino ethyl acrylate, the molar ratio of formic acid to ethyl acetate to dimethylamine is 1.5: 1: 1.1 through experiments, so that the molar yield of the reaction can reach more than 90%.
Drawings
FIG. 1 is a chromatogram of a finished product of ethyl N, N-dimethylaminoethyl acrylate of example 1 of the present invention.
Detailed Description
The present invention is described in detail below by way of examples, it should be noted that the following examples are only for illustrating the present invention and should not be construed as limiting the scope of the present invention, and those skilled in the art can make some insubstantial modifications and adaptations of the present invention based on the above-described disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art.
The chemical reagents used in the invention are all purchased reagents without special description, and the concentration is chemical purity.
Example 1
The preparation method of the N, N-dimethylamino ethyl acrylate comprises the following specific steps:
ethyl acetate (880kg, 10kmol) and a 40% dimethylamine aqueous solution (1237.5kg, 11kmol) were pumped into a 3000L stainless steel reactor in this order, the motor was started to stir, and after stirring was uniform, formic acid (690kg, 15kmol) was pumped in. After the feeding is finished, introducing steam into a jacket of the reaction kettle, raising the temperature in the kettle to 125 ℃, wherein the pressure of the reaction system is about 0.2MPa, then introducing nitrogen into the reaction kettle, pressurizing to 0.55MPa, and then starting to perform heat preservation and sealing reaction for 16 hours. When the pressure is reduced during the heat preservation, nitrogen is introduced to maintain the pressure to be stable at 0.55MPa.
And after the heat preservation is finished, circulating water is introduced into the jacket of the reaction kettle, and the temperature in the kettle is reduced to below 45 ℃. And after the temperature reduction is finished, transferring the obtained feed liquid into a freeze dryer, and enabling the water content in the product to be lower than 0.5% through a freeze-drying process so as to obtain the crude product of the N, N-dimethylamino ethyl acrylate.
After the freeze-drying is finished, transferring the crude product of the N, N-dimethylamino ethyl acrylate into a rectifying still for vacuum rectification, wherein the vacuum degree is 0.095MPa, the temperature is 150 ℃, and the finished product of the 1314.2 kg colorless and transparent N, N-dimethylamino ethyl acrylate is obtained, the molar yield is 91.9%, and the purity of a gas chromatography is 99.52%. The chromatogram of the finished product of N, N-dimethylaminoethyl acrylate is shown in FIG. 1, and the chromatographic analysis result of the finished product of N, N-dimethylaminoethyl acrylate is shown in Table 1.
TABLE 1 chromatographic analysis results Table
Example 2
The preparation method of the N, N-dimethylamino ethyl acrylate comprises the following specific steps:
ethyl acetate (880kg, 10kmol) and a 40% dimethylamine aqueous solution (1350kg, 12kmol) were pumped into a 3000L stainless steel reaction kettle in sequence, a motor was started to stir, and formic acid (644kg, 14kmol) was pumped after stirring was uniform. And after the feeding is finished, introducing steam into a jacket of the reaction kettle, raising the temperature in the kettle to 130 ℃, wherein the pressure of the reaction system is about 0.2MPa, then introducing nitrogen into the reaction kettle, pressurizing to 0.6MPa, and then starting heat preservation and closed reaction for 16 hours. When the pressure is reduced during the heat preservation, nitrogen is introduced to maintain the pressure to be stable at 0.6MPa.
And after the heat preservation is finished, circulating water is introduced into the jacket of the reaction kettle, and the temperature in the kettle is reduced to below 45 ℃. And after the temperature reduction is finished, transferring the obtained feed liquid into a freeze dryer, and enabling the water content in the product to be lower than 0.5% through a freeze-drying process so as to obtain the crude product of the N, N-dimethylamino ethyl acrylate.
After the freeze-drying is finished, transferring the crude product of the N, N-dimethylamino ethyl acrylate into a rectifying still for vacuum rectification, wherein the vacuum degree is 0.095MPa, the temperature is 150 ℃, and 1281.3kg of colorless and transparent finished product of the N, N-dimethylamino ethyl acrylate is obtained, the molar yield is 89.6%, and the purity of a gas chromatography is 99.49%.
Example 3
The preparation method of ethyl N, N-dimethylamino acrylate of this example comprises the following specific steps:
ethyl acetate (880kg, 10kmol) and a 40% dimethylamine aqueous solution (1125kg, 10kmol) were pumped into a 3000L stainless steel reactor in sequence, a motor was started to stir, and after stirring uniformly, formic acid (736kg, 169kmol) was pumped in. After the feeding is finished, steam is introduced into the jacket of the reaction kettle, the temperature in the kettle is raised to 127 ℃, the pressure of the reaction system is about 0.2MPa at the moment, then nitrogen is introduced into the reaction kettle to pressurize to 0.5MPa, and then the heat-preservation closed reaction is started for 16h. When the pressure is reduced during the heat preservation, nitrogen is introduced to maintain the pressure to be stable at 0.5MPa.
And after the heat preservation is finished, circulating water is introduced into the jacket of the reaction kettle, and the temperature in the kettle is reduced to below 45 ℃. And after the temperature reduction is finished, transferring the obtained feed liquid into a freeze dryer, and enabling the water content in the product to be lower than 0.5% through a freeze-drying process so as to obtain the crude product of the N, N-dimethylamino ethyl acrylate.
After the freeze-drying is finished, transferring the crude product of the N, N-dimethylamino ethyl acrylate into a rectifying still for vacuum rectification, wherein the vacuum degree is 0.095MPa, the temperature is 150 ℃, and 1278.4kg of colorless and transparent finished product of the N, N-dimethylamino ethyl acrylate is obtained, the molar yield is 89.4%, and the purity of a gas chromatography is 99.23%.
Example 4
The preparation method of the N, N-dimethylamino ethyl acrylate comprises the following specific steps:
ethyl acetate (880kg, 10kmol) and a dimethylamine aqueous solution (1237.5kg, 11kmol) with a concentration of 40% were pumped into a 3000L stainless steel reactor in sequence, a motor was started to stir, and after stirring uniformly, formic acid (690kg, 15kmol) was pumped in. After the feeding is finished, introducing steam into the jacket of the reaction kettle, raising the temperature in the kettle to 128 ℃, wherein the pressure of the reaction system is about 0.2MPa, then introducing nitrogen into the reaction kettle to pressurize to 0.52MPa, and then starting to perform heat preservation and sealing reaction for 16h. When the pressure is reduced during the heat preservation, nitrogen is introduced to maintain the pressure to be stable at 0.52MPa.
And after the heat preservation is finished, circulating water is introduced into the jacket of the reaction kettle, and the temperature in the kettle is reduced to below 45 ℃. And after the temperature reduction is finished, transferring the obtained feed liquid into a freeze dryer, and enabling the water content in the product to be lower than 0.5% through a freeze-drying process so as to obtain the crude product of the N, N-dimethylamino ethyl acrylate.
After the freeze-drying is finished, transferring the crude product of the N, N-dimethylamino ethyl acrylate into a rectifying still for vacuum rectification, wherein the vacuum degree is 0.095MPa, the temperature is 150 ℃, and 1289.9kg of colorless and transparent finished product of the N, N-dimethylamino ethyl acrylate is obtained, the molar yield is 90.2%, and the purity of a gas chromatography is 99.43%.
Example 5
The preparation method of the N, N-dimethylamino ethyl acrylate comprises the following specific steps:
ethyl acetate (880kg, 10kmol) and a 40% dimethylamine aqueous solution (1125kg, 10kmol) were pumped into a 3000L stainless steel reaction vessel in sequence, the motor was started to stir, and formic acid (644kg, 14kmol) was pumped after stirring was uniform. After the feeding is finished, introducing steam into a jacket of the reaction kettle, raising the temperature in the kettle to 127 ℃, wherein the pressure of the reaction system is about 0.2MPa, then introducing nitrogen into the reaction kettle to pressurize to 0.57MPa, and then starting to carry out heat preservation and closed reaction for 16h. When the pressure is reduced during the heat preservation, nitrogen is introduced to maintain the pressure to be stable at 0.57MPa.
And after the heat preservation is finished, circulating water is introduced into the jacket of the reaction kettle, and the temperature in the kettle is reduced to below 45 ℃. And after the temperature reduction is finished, transferring the obtained feed liquid into a freeze dryer, and enabling the water content in the product to be lower than 0.5% through a freeze-drying process so as to obtain the crude product of the N, N-dimethylamino ethyl acrylate.
After the freeze-drying is finished, transferring the crude product of the N, N-dimethylamino ethyl acrylate into a rectifying still for vacuum rectification at 150 ℃ under the vacuum degree of 0.095MPa to obtain 1268.4kg of colorless and transparent finished product of the N, N-dimethylamino ethyl acrylate, wherein the molar yield is 88.7 percent, and the purity of a gas chromatography is 98.87 percent.
Example 6
The preparation method of the N, N-dimethylamino ethyl acrylate comprises the following specific steps:
ethyl acetate (880kg, 10kmol) and a 40% dimethylamine aqueous solution (1350kg, 12kmol) were pumped into a 3000L stainless steel reactor, and after stirring, formic acid (736kg, 169kmol) was pumped into the reactor. After the feeding is finished, introducing steam into the jacket of the reaction kettle, raising the temperature in the kettle to 130 ℃, wherein the pressure of the reaction system is about 0.2MPa, then introducing nitrogen into the reaction kettle to pressurize to 0.55MPa, and then starting to perform heat preservation and sealing reaction for 16h. When the pressure is reduced during the heat preservation, nitrogen is introduced to maintain the pressure to be stable at 0.55MPa.
And after the heat preservation is finished, circulating water is introduced into the jacket of the reaction kettle, and the temperature in the kettle is reduced to below 45 ℃. And after the temperature reduction is finished, transferring the obtained feed liquid into a freeze dryer, and enabling the water content in the product to be lower than 0.5% through a freeze-drying process so as to obtain the crude product of the N, N-dimethylamino ethyl acrylate.
After the freeze-drying is finished, transferring the crude product of the N, N-dimethylamino ethyl acrylate into a rectifying still for vacuum rectification, wherein the vacuum degree is 0.095MPa, the temperature is 150 ℃, and 1284.2kg of colorless and transparent finished product of the N, N-dimethylamino ethyl acrylate is obtained, the molar yield is 89.8%, and the purity of a gas chromatography is 99.01%.
As can be seen from the examples, the present invention sets specific reaction conditions to achieve more desirable and superior effects.
It should be understood that the above examples are only for clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And such obvious changes and modifications as fall within the spirit of the invention are deemed to be within the scope of the invention.
Claims (7)
1. A preparation method of N, N-dimethylamino ethyl acrylate is characterized by comprising the following steps: formic acid, ethyl acetate and dimethylamine are heated to react to prepare N, N-dimethylamino ethyl acrylate and water, and the reaction formula is as follows:
the reaction temperature of the reaction is 120-150 ℃, the reaction pressure of the reaction is 0.4-0.8 MPa, and the pressure of the reaction is maintained under the protection of nitrogen.
2. The method for preparing N, N-dimethylaminoethyl acrylate according to claim 1, wherein: the reaction temperature is 125-130 ℃, and the reaction pressure is 0.5-0.6 MPa.
3. The method for preparing N, N-dimethylaminoethyl acrylate according to claim 1, wherein: the dimethylamine is a dimethylamine aqueous solution with the concentration of 30 to 50 percent.
4. The method for preparing N, N-dimethylaminoethyl acrylate according to claim 1, wherein: the molar weight ratio of the formic acid to the ethyl acetate to the dimethylamine is 1.4-1.6: 1-1.2.
5. The process for producing N, N-dimethylaminoethyl acrylate according to claim 4, wherein: the molar ratio of formic acid, ethyl acetate and dimethylamine is 1.5: 1: 1.1.
6. The process for the preparation of ethyl N, N-dimethylaminoacrylate according to any one of claims 1 to 5, characterized in that: the N, N-dimethylamino ethyl acrylate prepared by the reaction is frozen and dried to obtain a crude product of the N, N-dimethylamino ethyl acrylate with the water content of less than or equal to 0.5 percent.
7. The method for preparing N, N-dimethylaminoethyl acrylate according to claim 6, wherein: and carrying out vacuum rectification on the crude product of the N, N-dimethylamino ethyl acrylate to obtain a finished product of the N, N-dimethylamino ethyl acrylate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011011149.1A CN112300018B (en) | 2020-09-23 | 2020-09-23 | Preparation method of N, N-dimethylamino ethyl acrylate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011011149.1A CN112300018B (en) | 2020-09-23 | 2020-09-23 | Preparation method of N, N-dimethylamino ethyl acrylate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112300018A CN112300018A (en) | 2021-02-02 |
| CN112300018B true CN112300018B (en) | 2022-12-13 |
Family
ID=74489882
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011011149.1A Active CN112300018B (en) | 2020-09-23 | 2020-09-23 | Preparation method of N, N-dimethylamino ethyl acrylate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112300018B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5030747A (en) * | 1989-03-23 | 1991-07-09 | Bayer Aktiengesellschaft | Process for the preparation of μ-amino-acrylic acid esters |
| CN106008241A (en) * | 2016-06-13 | 2016-10-12 | 江西博晟医药科技有限公司 | Synthesis method for N,N-dimethylaminoethyl acrylate |
| CN106366008A (en) * | 2016-08-15 | 2017-02-01 | 浙江永太科技股份有限公司 | Acrylic acid diester compound and preparation method thereof |
-
2020
- 2020-09-23 CN CN202011011149.1A patent/CN112300018B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5030747A (en) * | 1989-03-23 | 1991-07-09 | Bayer Aktiengesellschaft | Process for the preparation of μ-amino-acrylic acid esters |
| CN106008241A (en) * | 2016-06-13 | 2016-10-12 | 江西博晟医药科技有限公司 | Synthesis method for N,N-dimethylaminoethyl acrylate |
| CN106366008A (en) * | 2016-08-15 | 2017-02-01 | 浙江永太科技股份有限公司 | Acrylic acid diester compound and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 曾志玲.喹诺酮类药物关键中间体3-N,N-二甲氨基丙烯酸乙酯合成方法综述.《广东化工》.2012,第39卷(第15期),32-34页. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112300018A (en) | 2021-02-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110551278B (en) | Supported catalyst and preparation method and application thereof | |
| CN102516117A (en) | Process for producing methyl hydrazine with hydrazine hydrate method | |
| US2458214A (en) | Hydrogenation of nitro compounds | |
| CN104447366A (en) | Preparation method of high-purity 2-amino-3, 5-dibromobenzaldehyde | |
| CN112300018B (en) | Preparation method of N, N-dimethylamino ethyl acrylate | |
| CN105085282B (en) | Preparation method for alkyl alcohol amine | |
| CN102020543B (en) | Method for producing 9-fluorenone | |
| CN113788765A (en) | Preparation method of alpha, beta-unsaturated amide | |
| CN111269151B (en) | Method for preparing taurine from sodium isethionate | |
| CN108752217B (en) | Synthesis method of dolutegravir key intermediate 2, 4-difluorobenzylamine | |
| CN109053559B (en) | Preparation method of 5-methoxymethyl-2, 3-pyridine dimethyl diformate | |
| CN111116386A (en) | Synthetic method of hydroxyethyl ethylenediamine | |
| CN113880689B (en) | Preparation method of 3-methyl-1, 5-pentanediol | |
| JPS6160636A (en) | Manufacture of amine | |
| CN105348285B (en) | Low-cost and high-yield adenine preparation method | |
| CN110590702B (en) | Novel method for preparing 2-mercaptobenzothiazole | |
| CN110003023B (en) | Preparation method of environment-friendly N, N-dimethylformamide dimethyl acetal | |
| CN114522737A (en) | Method for preparing 3-acetoxy propanol with high selectivity | |
| CN107382772B (en) | Process for synthesizing high-purity dodecanitrile by pressure catalysis | |
| CN108017524B (en) | Preparation method of 3, 4, 5-trimethoxybenzaldehyde | |
| CN112209821A (en) | Preparation method of chromium propionate | |
| CN111662182A (en) | Method for producing phenylenediamine by dinitrobenzene solvent-free hydrogenation continuous reaction | |
| CN105001096B (en) | A kind of method for preparing 4 amino N alkylbenzylamines | |
| CN109438396B (en) | Preparation method of tetrahydrofuran-3-methylamine | |
| CN115286483B (en) | Method for preparing trifluoroethanol from vinylidene fluoride |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CP01 | Change in the name or title of a patent holder | ||
| CP01 | Change in the name or title of a patent holder |
Address after: 223800 Jiangsu Suqian Suyu ecological Chemical Technology Industrial Park Zhongxing Road North End Patentee after: Kelaibo (Jiangsu) Technology Co.,Ltd. Address before: 223800 Jiangsu Suqian Suyu ecological Chemical Technology Industrial Park Zhongxing Road North End Patentee before: SUQIAN KEYLAB BIOCHEMICAL CO.,LTD. |