CN111732533A - Method for preparing N- (6-chloro-3-picolyl) methylamine by using microchannel reactor - Google Patents
Method for preparing N- (6-chloro-3-picolyl) methylamine by using microchannel reactor Download PDFInfo
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- CN111732533A CN111732533A CN202010559105.6A CN202010559105A CN111732533A CN 111732533 A CN111732533 A CN 111732533A CN 202010559105 A CN202010559105 A CN 202010559105A CN 111732533 A CN111732533 A CN 111732533A
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- chloro
- picolyl
- methylamine
- microchannel reactor
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- XALCOJXGWJXWBL-UHFFFAOYSA-N 1-(6-chloropyridin-3-yl)-n-methylmethanamine Chemical compound CNCC1=CC=C(Cl)N=C1 XALCOJXGWJXWBL-UHFFFAOYSA-N 0.000 title claims abstract description 41
- 238000000034 method Methods 0.000 title claims abstract description 22
- 238000006243 chemical reaction Methods 0.000 claims abstract description 33
- 239000000243 solution Substances 0.000 claims abstract description 31
- BAVYZALUXZFZLV-UHFFFAOYSA-N Methylamine Chemical compound NC BAVYZALUXZFZLV-UHFFFAOYSA-N 0.000 claims abstract description 30
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 15
- SKCNYHLTRZIINA-UHFFFAOYSA-N 2-chloro-5-(chloromethyl)pyridine Chemical compound ClCC1=CC=C(Cl)N=C1 SKCNYHLTRZIINA-UHFFFAOYSA-N 0.000 claims abstract description 14
- 239000007864 aqueous solution Substances 0.000 claims abstract description 14
- 239000000203 mixture Substances 0.000 claims abstract description 13
- HTZCNXWZYVXIMZ-UHFFFAOYSA-M benzyl(triethyl)azanium;chloride Chemical compound [Cl-].CC[N+](CC)(CC)CC1=CC=CC=C1 HTZCNXWZYVXIMZ-UHFFFAOYSA-M 0.000 claims abstract description 12
- 239000003960 organic solvent Substances 0.000 claims abstract description 9
- 238000003756 stirring Methods 0.000 claims abstract description 8
- 239000007788 liquid Substances 0.000 claims abstract description 6
- 238000005406 washing Methods 0.000 claims abstract description 6
- 238000005086 pumping Methods 0.000 claims abstract description 4
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 18
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical group ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 claims description 12
- 230000035484 reaction time Effects 0.000 claims description 7
- SCYULBFZEHDVBN-UHFFFAOYSA-N 1,1-Dichloroethane Chemical compound CC(Cl)Cl SCYULBFZEHDVBN-UHFFFAOYSA-N 0.000 claims description 6
- 239000000463 material Substances 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 239000011259 mixed solution Substances 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- WCXDHFDTOYPNIE-RIYZIHGNSA-N (E)-acetamiprid Chemical compound N#C/N=C(\C)N(C)CC1=CC=C(Cl)N=C1 WCXDHFDTOYPNIE-RIYZIHGNSA-N 0.000 description 1
- -1 2-chloro-5-chloromethyl pyridine toluene Chemical compound 0.000 description 1
- 239000005875 Acetamiprid Substances 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 238000003889 chemical engineering Methods 0.000 description 1
- 239000012295 chemical reaction liquid Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000012847 fine chemical Substances 0.000 description 1
- 239000002917 insecticide Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229920002545 silicone oil Polymers 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
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Classifications
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
- C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
- C07D213/04—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
- C07D213/60—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom 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
- C07D213/61—Halogen atoms or nitro radicals
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J19/0093—Microreactors, e.g. miniaturised or microfabricated reactors
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J2219/00049—Controlling or regulating processes
- B01J2219/00164—Controlling or regulating processes controlling the flow
- B01J2219/00166—Controlling or regulating processes controlling the flow controlling the residence time inside the reactor vessel
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Pyridine Compounds (AREA)
Abstract
The application discloses a method for preparing N- (6-chloro-3-picolyl) methylamine by a microchannel reactor, which comprises the following steps: A. adding a monomethylamine aqueous solution and a TEBAC aqueous solution into a silk mouth bottle, and shaking up to form a solution for later use; B. adding liquid 2-chloro-5-chloromethylpyridine and an organic solvent into a four-mouth bottle provided with a stirring and condensing pipe and a thermometer, and stirring to form a uniform and stable solution for later use; C. pumping the two solutions into a microchannel reactor simultaneously to react to obtain a mixture containing N- (6-chloro-3-picolyl) methylamine; D. separating the mixture containing N- (6-chloro-3-picolyl) methylamine, extracting with water layer, washing oil layer with water, combining oil layer and distilling to obtain N- (6-chloro-3-picolyl) methylamine. The reaction efficiency is greatly improved, the safety performance is greatly improved, the microchannel reactor is provided with 10 reaction modules, the reaction can be more sufficient, the yield of the product is improved, the yield is improved to 92% from 86%, and the yield is improved by 6% compared with a kettle type process.
Description
Technical Field
The application relates to the field of fine chemical engineering, in particular to a method for preparing N- (6-chloro-3-picolyl) methylamine by using a microchannel reactor.
Background
N- (6-chloro-3-picolyl) methylamine is an important intermediate for preparing an insecticide acetamiprid. The synthesis method adopted in the existing factory is that 30% monomethylamine aqueous solution is added into a reaction kettle, the temperature is reduced to-5 ℃, 2-chloro-5-chloromethyl pyridine toluene solution is dripped to generate N- (6-chloro-3-picolyl) methylamine, and the refined N- (6-chloro-3-picolyl) methylamine is obtained after extraction, water washing and layering are carried out, and an oil layer is distilled to remove a solvent. The material synthesized by adopting the reaction kettle has the defects of large liquid holdup, long reaction time and the like, and has low yield and larger potential safety hazard.
As disclosed in the chinese patent application: CN102827070A, published: 12/19/2012, the name of the invention is: an improved process for the synthesis of N- (6-chloro-3-picolyl) methylamine, examples of which mention the industrial synthesis of N- (6-chloro-3-picolyl) methylamine. But the preparation method is intermittent, the total reaction time is 4-6 hours, and the productivity is small. And large batch of materials exist in the reaction kettle, so that the potential safety hazard is great. The existing literature reports that the reaction is intermittent, the reaction time is long, and the product yield is low.
Disclosure of Invention
The application provides a method for preparing N- (6-chloro-3-picolyl) methylamine by using a microchannel reactor, which solves the problems of long reaction time, low product yield and great potential safety hazard in the preparation process of N- (6-chloro-3-picolyl) methylamine in the prior art.
The application provides a method for preparing N- (6-chloro-3-picolyl) methylamine by a microchannel reactor, which comprises the following steps:
A. adding a monomethylamine aqueous solution and a TEBAC aqueous solution into a silk mouth bottle, and shaking up to form a solution for later use;
B. adding liquid 2-chloro-5-chloromethylpyridine and an organic solvent into a four-mouth bottle provided with a stirring and condensing pipe and a thermometer, and stirring to form a uniform and stable solution for later use;
C. pumping the two solutions into a microchannel reactor simultaneously to react to obtain a mixture containing N- (6-chloro-3-picolyl) methylamine;
D. separating the mixture containing N- (6-chloro-3-picolyl) methylamine, extracting with water layer, washing oil layer with water, combining oil layer and distilling to obtain N- (6-chloro-3-picolyl) methylamine.
Further, a method for preparing N- (6-chloro-3-picolyl) methylamine by using a microchannel reactor, wherein the reaction time in the microchannel reactor is 20-120s, the reaction temperature is 15-45 ℃, and the pressure is 0.05-1.0 Mpa.
Further, the method for preparing the N- (6-chloro-3-picolyl) methylamine by the microchannel reactor comprises the step of introducing the 2-chloro-5-chloromethylpyridine into the microchannel reactor, wherein the mass ratio of the monomethylamine to the TEBAC is 1:8-20: 0.01-0.05.
Further, the mass flow of the 2-chloro-5-chloromethylpyridine organic solution is 3-100g/min, and the mass flow of the mixed solution of monomethylamine and TEBAC is 7-650 g/min.
Further, the method for preparing the N- (6-chloro-3-picolyl) methylamine by using the microchannel reactor comprises the step of preparing the N- (6-chloro-3-picolyl) methylamine by using chloroform, dichloroethane and toluene as organic solvents.
Further, the mass fraction of the 2-chloro-5-chloromethylpyridine organic solution is 30-60%, the mass fraction of the monomethylamine aqueous solution is 35-45%, and the mass fraction of the TEBAC solution is 0.2-0.4%.
Further, the method for preparing the N- (6-chloro-3-picolyl) methylamine by the microchannel reactor adopts chloroform, dichloroethane and toluene as extracting agents for extracting the water layer.
According to the technical scheme, the application provides the method for preparing the N- (6-chloro-3-picolyl) methylamine by the microchannel reactor, the microchannel reactor is adopted, the reaction time is reduced to 30-60s from indirect 4-6 hours, continuous production can be realized, the reaction efficiency is greatly improved, the reaction volume of the microchannel reactor is small and is only 20-200ml, compared with a traditional reaction kettle, the safety performance is greatly improved, the microchannel reactor is provided with 10 reaction modules, the reaction can be more fully performed, the product yield is improved, the yield is improved to 92% from 86%, and the yield is improved by 6% compared with a kettle type process.
Drawings
In order to more clearly illustrate the technical solution of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious to those skilled in the art that other drawings can be obtained according to the drawings without any creative effort.
FIG. 1 is a schematic view of a microchannel reactor according to the present application;
FIG. 2 shows the reaction equation of the present application.
Illustration of the drawings:
Detailed Description
In order to make those skilled in the art better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.
See FIGS. 1-2
According to the technical scheme, the method for preparing the N- (6-chloro-3-picolyl) methylamine by using the microchannel reactor comprises the following steps:
A. adding a monomethylamine aqueous solution and a TEBAC aqueous solution into a silk mouth bottle, and shaking up to form a solution for later use;
B. adding liquid 2-chloro-5-chloromethylpyridine and an organic solvent into a four-mouth bottle provided with a stirring and condensing pipe and a thermometer, and stirring to form a uniform and stable solution for later use;
C. pumping the two solutions into a microchannel reactor simultaneously to react to obtain a mixture containing N- (6-chloro-3-picolyl) methylamine;
D. separating the mixture containing N- (6-chloro-3-picolyl) methylamine, extracting with water layer, washing oil layer with water, combining oil layer and distilling to obtain N- (6-chloro-3-picolyl) methylamine.
During actual operation, a monomethylamine aqueous solution and a TEBAC aqueous solution are added into a silk-mouth bottle and are shaken up to form a solution; then, the liquid 2-chloro-5-chloromethylpyridine and the organic solvent were added to a four-necked flask equipped with a stirrer, a condenser and a thermometer, and stirred to form a uniform stable solution. The two solutions are respectively pumped into a microchannel reactor at the same time, the microchannel reactor is preferably a CS series microchannel reactor produced by Shandong Haimai company, the microchannel reactor is provided with ten reaction modules which are connected in series, the reaction modules are in a heart-shaped structure, the materials of the reaction modules and the preheating part of the microchannel reactor are Ha C276 or stainless steel 316L, the first reaction module has the main function of preheating the two solutions to the reaction temperature, and the main reactions are from the second reaction module to the tenth reaction module, namely, the second reaction module to the tenth reaction module are completely reacted to obtain a mixture containing N- (6-chloro-3-picolyl) methylamine. And the number of specific microchannel reactor modules in the subsequent series can be adjusted according to the reaction feed flow rate and residence time.
The two solutions are introduced into a micro-channel reactor through a diaphragm metering pump to be preheated to the reaction temperature, and the two solutions are synchronously introduced into a first micro-channel reaction module to carry out mixing reaction. The resulting mixture was fully reacted in the second to tenth microchannel reaction modules in the subsequent series to give a mixture containing N- (6-chloro-3-picolyl) methylamine. The temperature of the reaction module is controlled by an external heat exchange device, and the heat exchange medium is heat-conducting silicone oil. And (2) enabling the mixture at the reaction liquid outlet to flow into a reaction kettle with a jacket, introducing circulating water into the jacket for cooling, standing and layering the materials in the kettle, extracting a water layer by using the same organic solvent, combining an extraction oil layer and a reaction oil layer, adding water for washing once, distilling the oil layer, and obtaining the high-purity N- (6-chloro-3-picolyl) methylamine in the kettle. Wherein the yield of the target product is 92 percent, and the purity is more than 95 percent.
Preferably, the mass ratio of the 2-chloro-5-chloromethylpyridine to monomethylamine and TEBAC introduced into the microchannel reactor is 1:8-20: 0.01-0.05.
Preferably, the mass flow rate of the 2-chloro-5-chloromethylpyridine organic solution is 3-100g/min, and the mass flow rate of the mixed solution of monomethylamine and TEBAC is 7-650 g/min.
Preferably, the organic solvent is chloroform, dichloroethane, toluene.
Preferably, the mass fraction of the 2-chloro-5-chloromethylpyridine organic solution is 30-60%, the mass fraction of the monomethylamine aqueous solution is 35-45%, and the mass fraction of the TEBAC solution is 0.2-0.4%.
Preferably, the extractant used for extracting the water layer is chloroform, dichloroethane or toluene.
Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope of the disclosure being indicated by the following claims.
It will be understood that the present application is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The above-described embodiments of the present application do not limit the scope of the present application.
Claims (7)
1. A method for preparing N- (6-chloro-3-picolyl) methylamine by a microchannel reactor is characterized by comprising the following steps:
A. adding a monomethylamine aqueous solution and a TEBAC aqueous solution into a silk mouth bottle, and shaking up to form a solution for later use;
B. adding liquid 2-chloro-5-chloromethylpyridine and an organic solvent into a four-mouth bottle provided with a stirring and condensing pipe and a thermometer, and stirring to form a uniform and stable solution for later use;
C. pumping the two solutions into a microchannel reactor simultaneously to react to obtain a mixture containing N- (6-chloro-3-picolyl) methylamine;
D. separating the mixture containing N- (6-chloro-3-picolyl) methylamine, extracting with water layer, washing oil layer with water, combining oil layer and distilling to obtain N- (6-chloro-3-picolyl) methylamine.
2. The method for preparing N- (6-chloro-3-picolyl) methylamine by using the microchannel reactor as claimed in claim 1, wherein the reaction time in the microchannel reactor is 20-120s, the reaction temperature is 15-45 ℃, and the pressure is 0.05-1.0 MPa.
3. The method for preparing N- (6-chloro-3-picolyl) methylamine by using a microchannel reactor, according to claim 1, wherein the amount ratio of the 2-chloro-5-chloromethylpyridine to the monomethylamine and the TEABAC introduced into the microchannel reactor is 1:8-20: 0.01-0.05.
4. The method for preparing N- (6-chloro-3-picolyl) methylamine with a microchannel reactor as claimed in claim 1, wherein the mass flow rate of the 2-chloro-5-chloromethylpyridine organic solution is 3-100g/min, and the mass flow rate of the mixture of monomethylamine and TEABC is 7-650 g/min.
5. The method for preparing N- (6-chloro-3-picolyl) methylamine by using the microchannel reactor as claimed in claim 1, wherein the organic solvent is chloroform, dichloroethane or toluene.
6. The method for preparing N- (6-chloro-3-picolyl) methylamine by using a microchannel reactor as claimed in claim 1, wherein the mass fraction of the 2-chloro-5-chloromethylpyridine organic solution is 30-60%, the mass fraction of the monomethylamine aqueous solution is 35-45%, and the mass fraction of the TEBAC solution is 0.2-0.4%.
7. The method for preparing N- (6-chloro-3-picolyl) methylamine by using the microchannel reactor as claimed in claim 1, wherein the extractant used for extracting the water layer is chloroform, dichloroethane or toluene.
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| CN202010559105.6A CN111732533B (en) | 2020-06-18 | 2020-06-18 | Method for preparing N- (6-chloro-3-picolyl) methylamine by micro-channel reactor |
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| CN202010559105.6A CN111732533B (en) | 2020-06-18 | 2020-06-18 | Method for preparing N- (6-chloro-3-picolyl) methylamine by micro-channel reactor |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103242225A (en) * | 2012-02-13 | 2013-08-14 | 湖南化工研究院 | Picolinate amino pyridine compound and preparation method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103242225A (en) * | 2012-02-13 | 2013-08-14 | 湖南化工研究院 | Picolinate amino pyridine compound and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 朱梅等: "微通道反应器在合成工艺改进中的应用研究进展", 《合成化学》 * |
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