CN108329198B - Preparation method of tetrahydro ionone - Google Patents
Preparation method of tetrahydro ionone Download PDFInfo
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- CN108329198B CN108329198B CN201810332792.0A CN201810332792A CN108329198B CN 108329198 B CN108329198 B CN 108329198B CN 201810332792 A CN201810332792 A CN 201810332792A CN 108329198 B CN108329198 B CN 108329198B
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/61—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups
- C07C45/62—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by hydrogenation of carbon-to-carbon double or triple bonds
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/78—Separation; Purification; Stabilisation; Use of additives
- C07C45/81—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation
- C07C45/82—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation by distillation
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Abstract
The invention discloses a preparation method of tetrahydro ionone, which comprises the steps of putting ionone and Raney nickel catalyst into a high-pressure reaction kettle, adding a solvent and a stabilizer, introducing hydrogen, controlling the hydrogen pressure and the reaction temperature of materials in the high-pressure reaction kettle under reaction conditions, carrying out pressure-maintaining and heat-preserving reaction, continuously carrying out sampling analysis, and adjusting the reaction conditions of subsequent reaction according to the content changes of raw material ionone and intermediate product dihydro ionone; when the content of the dihydroionone in the high-pressure reaction kettle is less than or equal to 2 percent, stopping adding hydrogen and heating materials into the high-pressure reaction kettle, replacing the hydrogen in the high-pressure reaction kettle with nitrogen, and stopping the reaction; and after the materials are cooled, settling, filtering and discharging to obtain the tetrahydro ionone. The method can solve the problems of high hydrogenation reaction temperature and high hydrogen pressure, is green, low in energy consumption and safe, and has the advantages of high yield and high product purity.
Description
Technical Field
The invention relates to a preparation method of a terpenoid, in particular to a preparation method of tetrahydro ionone.
Background
Tetrahydroionone, also known as 6, 10-dimethyl-9-undecen-2-one, having the molecular formula C13H24O, molecular weight 196.33, is a synthetic organic compound. The tetrahydro ionone has the fragrance of aucklandia, flower and fruit, similar to violet, rose and sweet fruit, and has apple and peach fragrance for use as essence. The tetrahydro ionone can be prepared by hydrogenation of ionone in the presence of colloidal palladium, or by reaction of linalool, acetic anhydride and sodium ethoxide followed by hydrogenation, or by reaction of geraniol with an acid chloride. The tetrahydro ionone is mostly prepared by taking ionone as a raw material through hydrogenation catalysis, and at present, no relevant literature report and industrial production exist temporarily.
Disclosure of Invention
The invention aims to provide a preparation method of tetrahydro ionone. The method can solve the problems of high temperature and high hydrogen pressure of the existing hydrogenation reaction, is green, low in energy consumption and safe, and has the advantages of high yield and high product purity.
The above purpose of the invention is realized by the following technical scheme: a preparation method of tetrahydro ionone comprises the following steps:
(1) adding ionone and Raney nickel catalyst into a high-pressure reaction kettle, adding a solvent and a stabilizer, introducing nitrogen to replace air, introducing hydrogen to replace nitrogen, controlling the hydrogen pressure in the high-pressure reaction kettle within the range of 0.5-1 MPa, keeping the reaction temperature of materials in the high-pressure reaction kettle at 40-50 ℃, performing pressure-maintaining and heat-preserving reaction, and continuously performing sampling analysis in the reaction process so as to adjust the reaction conditions of subsequent reaction according to the content changes of raw material ionone, intermediate product dihydroionone and product tetrahydroionone;
(2) when the content of ionone in the high-pressure reaction kettle is less than or equal to 3 percent, adjusting the hydrogen pressure to 1.0-1.5 MPa, adjusting the reaction temperature to 50-60 ℃, and performing pressure-maintaining and heat-preserving reaction;
(3) when the content of the intermediate product dihydroionone in the high-pressure reaction kettle is less than or equal to 2 percent, stopping adding hydrogen into the high-pressure reaction kettle, stopping heating the materials in the high-pressure reaction kettle, replacing the hydrogen in the high-pressure reaction kettle with nitrogen, and stopping the reaction;
(4) after the materials in the high-pressure reaction kettle are cooled, settling, filtering and discharging to obtain a mixture of the tetrahydro ionone and the solvent;
(5) and adding the mixture of the tetrahydro ionone and the solvent into a distillation kettle, and distilling to recover the solvent to obtain the tetrahydro ionone.
In the step (5), the solvent is recovered by initially distilling at normal pressure, and the content of the solvent in the kettle is monitored; when the content of the solvent in the distillation kettle is less than or equal to 10%, adjusting the pressure in the distillation kettle to 20-30 kPa, adjusting the temperature in the distillation kettle to 100-110 ℃, and continuing to distill and recover the solvent; when the content of the solvent in the distillation kettle is less than or equal to 3%, adjusting the pressure in the distillation kettle to 3-10 kPa, and adjusting the temperature in the distillation kettle to 110-120 ℃; and when the content of the solvent in the distillation kettle is less than or equal to 0.5 percent, stopping heating the materials in the distillation kettle, reducing the temperature in the kettle to normal temperature, replacing the air in the kettle with nitrogen, filtering, and discharging to obtain the tetrahydro ionone.
The ionone is synthetic or natural, and the content of the ionone is more than or equal to 95 percent.
The mass ratio of the ionone to the Raney nickel catalyst to the solvent to the stabilizer is 1: 0.01-0.03: 1.6-2.2: 0.002-0.005.
The raney nickel catalyst is preferably of the type RTH3110 Ni.
The solvent is ethanol, and the stabilizer is triethanolamine.
In the step (4), the Raney nickel catalyst obtained after filtration is repeatedly applied to the reaction of the next batch.
In the step (5), the solvent recovered by distillation is repeatedly used in the reaction of the next batch.
The invention has the following advantages:
1. the inventor continuously changes the factors such as screening of the reaction catalyst, reaction pressure, temperature and the like through years of researches on the component structure of the terpene and repeated hydrogenation tests, analyzes the reasons, and finally discovers that the reaction temperature and the hydrogenation pressure have great influence on the yield of the tetrahydro ionone in the reaction. If a reaction temperature and a hydrogenation pressure are fixed, the yield is difficult to reach the highest point, and the reaction end point is difficult to reach in the later period of the reaction. The invention analyzes and tracks the reaction progress in the high-pressure reaction kettle, and controls the reaction temperature and the hydrogenation pressure according to the corresponding adjustment of the reaction depth, so that the reaction is carried out in a mild and orderly way towards the direction of high yield of the tetrahydro ionone, thereby achieving the purpose of improving the yield and the purity of the tetrahydro ionone.
2. The Raney nickel catalysts with different types have different catalytic effects, the Raney nickel catalyst with the type RTH3110Ni is preferably used as the hydrogenation catalyst in the invention, and the organic solvent ethanol is added, so that the problems of high temperature and high hydrogen pressure of the existing hydrogenation reaction can be solved, the energy consumption of the reaction is reduced, and the reaction is milder and safer.
3. The Raney nickel catalyst and the solvent obtained by filtering after the reaction can be reused.
4. The inventor analyzes and researches the byproducts, inhibits the generation of the byproducts by adding a trace amount of stabilizing agent, leads the reaction to be carried out towards the direction of generating the tetrahydro ionone, and finds that the reaction effect of triethanolamine as the stabilizing agent is the best through continuously screening the stabilizing agent.
Detailed Description
The present invention will be described in further detail with reference to the following embodiments, but the present invention is not limited thereto.
Example 1
(1) Adding 40g of 97.1 percent ionone and 1.2g of Raney nickel catalyst into a high-pressure reaction kettle, and adding 88g of ethanol and 0.2g of triethanolamine, wherein the mass ratio of the ionone to the Raney nickel catalyst to the solvent to the stabilizer is 1:0.03:2.2: 0.005. And replacing the air in the high-pressure reaction kettle with nitrogen for three times, replacing the air with hydrogen for three times, finally introducing the hydrogen again, and controlling the pressure of the hydrogen in the high-pressure reaction kettle to be 0.5 MPa. Keeping the reaction temperature of the materials in the high-pressure reaction kettle at 40 ℃ and carrying out pressure-maintaining and heat-preserving reaction. Sampling and analyzing are carried out after the reaction is carried out for 2 hours, so that the reaction conditions of the subsequent reaction are adjusted according to the content changes of the raw material ionone, the intermediate product dihydroionone and the product tetrahydroionone.
(2) When the content of the ionone in the high-pressure reaction kettle is less than or equal to 3 percent, adjusting the hydrogen pressure to 1.0MPa, adjusting the reaction temperature to 50 ℃, and carrying out pressure-maintaining and heat-preserving reaction.
(3) When the content of the intermediate product dihydroionone in the high-pressure reaction kettle is less than or equal to 2 percent, stopping adding hydrogen into the high-pressure reaction kettle, stopping heating the materials in the high-pressure reaction kettle, replacing the hydrogen in the high-pressure reaction kettle with nitrogen, and stopping the reaction.
(4) And after the materials in the high-pressure reaction kettle are cooled, settling, filtering and discharging to obtain a mixture of the tetrahydro ionone and the solvent. The Raney nickel catalyst obtained after filtration is repeatedly applied to the reaction of the next batch.
(5) And adding the mixture of the tetrahydro ionone and the solvent into a distillation kettle, and distilling at normal pressure to recover the solvent. When the content of the solvent in the distillation kettle is less than or equal to 10 percent, starting a vacuum pump for reduced pressure distillation, adjusting the pressure in the kettle to 20kPa, and adjusting the temperature in the kettle to 100 ℃; when the solvent content in the distillation kettle is less than or equal to 3 percent, adjusting the pressure in the kettle to 4kPa, and adjusting the temperature in the kettle to 110 ℃.
(6) And when the content of the solvent in the distillation kettle is less than or equal to 0.5 percent, stopping heating the materials in the distillation kettle, reducing the temperature in the kettle to normal temperature, replacing the air in the kettle with nitrogen, filtering, and discharging to obtain the tetrahydro ionone. The solvent recovered by distillation was repeatedly used in the reaction of the next batch.
(7) Product analysis of the prepared tetrahydro ionone: the content of the tetrahydro ionone is 88.6 percent, the ionone is 0, the conversion rate is 100 percent, and the selectivity of the tetrahydro ionone is 91.25 percent.
Example 2
(1) 100g of ionone with the content of 96.8 percent and 2g of Raney nickel catalyst are added into a high-pressure reaction kettle, 190g of ethanol and 0.35g of triethanolamine are added, namely, the mass ratio of the ionone to the Raney nickel catalyst to the solvent to the stabilizer is 1:0.02:1.9: 0.0035. And replacing the air in the high-pressure reaction kettle with nitrogen for three times, replacing the air with hydrogen for three times, finally introducing the hydrogen again, and controlling the pressure of the hydrogen in the high-pressure reaction kettle to be 0.7 MPa. Keeping the reaction temperature of the materials in the high-pressure reaction kettle at 45 ℃ and carrying out pressure-maintaining and heat-preserving reaction. Sampling and analyzing are carried out after the reaction is carried out for 2 hours, so that the reaction conditions of the subsequent reaction are adjusted according to the content changes of the raw material ionone, the intermediate product dihydroionone and the product tetrahydroionone.
(2) When the content of the ionone in the high-pressure reaction kettle is less than or equal to 3 percent, adjusting the hydrogen pressure to 1.2MPa, adjusting the reaction temperature to 55 ℃, and carrying out pressure-maintaining and heat-preserving reaction.
(3) When the content of the intermediate product dihydroionone in the high-pressure reaction kettle is less than or equal to 2 percent, stopping adding hydrogen into the high-pressure reaction kettle, stopping heating the materials in the high-pressure reaction kettle, replacing the hydrogen in the high-pressure reaction kettle with nitrogen, and stopping the reaction.
(4) And after the materials in the high-pressure reaction kettle are cooled, settling, filtering and discharging to obtain a mixture of the tetrahydro ionone and the solvent. The Raney nickel catalyst obtained after filtration is repeatedly applied to the reaction of the next batch.
(5) And adding the mixture of the tetrahydro ionone and the solvent into a distillation kettle, and distilling at normal pressure to recover the solvent. When the content of the solvent in the distillation kettle is less than or equal to 10 percent, starting a vacuum pump for reduced pressure distillation, adjusting the pressure in the kettle to 25kPa, and adjusting the temperature in the kettle to 105 ℃; when the solvent content in the distillation kettle is less than or equal to 3 percent, adjusting the pressure in the kettle to 8kPa, and adjusting the temperature in the kettle to 115 ℃.
(6) And when the content of the solvent in the distillation kettle is less than or equal to 0.5 percent, stopping heating the materials in the distillation kettle, reducing the temperature in the kettle to normal temperature, replacing the air in the kettle with nitrogen, filtering, and discharging to obtain the tetrahydro ionone. The solvent recovered by distillation was repeatedly used in the reaction of the next batch.
(7) Product analysis of the prepared tetrahydro ionone: the content of the tetrahydro ionone is 88.2 percent, the ionone is 0, the conversion rate is 100 percent, and the selectivity of the tetrahydro ionone is 91.12 percent.
Example 3
(1) Adding 400g of ionone with the content of 96.2% and 4g of Raney nickel catalyst into a high-pressure reaction kettle, and adding 640g of ethanol and 0.8g of triethanolamine, wherein the mass ratio of the ionone, the Raney nickel catalyst, the solvent and the stabilizer is 1:0.01:1.66: 0.002. And replacing the air in the high-pressure reaction kettle with nitrogen for three times, replacing the air with hydrogen for three times, finally introducing the hydrogen again, and controlling the pressure of the hydrogen in the high-pressure reaction kettle to be 1 MPa. Keeping the reaction temperature of the materials in the high-pressure reaction kettle at 50 ℃ and carrying out pressure-maintaining and heat-preserving reaction. Sampling and analyzing are carried out after the reaction is carried out for 2 hours, so that the reaction conditions of the subsequent reaction are adjusted according to the content changes of the raw material ionone, the intermediate product dihydroionone and the product tetrahydroionone.
(2) When the content of the ionone in the high-pressure reaction kettle is less than or equal to 3 percent, adjusting the hydrogen pressure to 1.5MPa, adjusting the reaction temperature to 60 ℃, and carrying out pressure-maintaining and heat-preserving reaction.
(3) When the content of the intermediate product dihydroionone in the high-pressure reaction kettle is less than or equal to 2 percent, stopping adding hydrogen into the high-pressure reaction kettle, stopping heating the materials in the high-pressure reaction kettle, replacing the hydrogen in the high-pressure reaction kettle with nitrogen, and stopping the reaction.
(4) And after the materials in the high-pressure reaction kettle are cooled, settling, filtering and discharging to obtain a mixture of the tetrahydro ionone and the solvent. The Raney nickel catalyst obtained after filtration is repeatedly applied to the reaction of the next batch.
(5) And adding the mixture of the tetrahydro ionone and the solvent into a distillation kettle, and distilling at normal pressure to recover the solvent. When the content of the solvent in the distillation kettle is less than or equal to 10 percent, starting a vacuum pump for reduced pressure distillation, adjusting the pressure in the kettle to 30kPa, and adjusting the temperature in the kettle to 110 ℃; when the solvent content in the distillation kettle is less than or equal to 3 percent, adjusting the pressure in the kettle to 10kPa, and adjusting the temperature in the kettle to 120 ℃.
(6) And when the content of the solvent in the distillation kettle is less than or equal to 0.5 percent, stopping heating the materials in the distillation kettle, reducing the temperature in the kettle to normal temperature, replacing the air in the kettle with nitrogen, filtering, and discharging to obtain the tetrahydro ionone. The solvent recovered by distillation was repeatedly used in the reaction of the next batch.
(7) Product analysis of the prepared tetrahydro ionone: the content of the tetrahydro ionone is 87.4%, the ionone is 0, the conversion rate is 100%, and the selectivity of the tetrahydro ionone is 90.85%.
Claims (7)
1. The preparation method of the tetrahydro ionone is characterized by comprising the following steps:
(1) adding ionone and Raney nickel catalyst into a high-pressure reaction kettle, adding a solvent and a stabilizer, introducing nitrogen to replace air, introducing hydrogen to replace nitrogen, controlling the hydrogen pressure in the high-pressure reaction kettle within the range of 0.5-1 MPa, keeping the reaction temperature of materials in the high-pressure reaction kettle at 40-50 ℃, performing pressure-maintaining and heat-preserving reaction, and continuously performing sampling analysis in the reaction process so as to adjust the reaction conditions of subsequent reaction according to the content changes of raw material ionone, intermediate product dihydroionone and product tetrahydroionone;
(2) when the content of ionone in the high-pressure reaction kettle is less than or equal to 3 percent, adjusting the hydrogen pressure to 1.0-1.5 MPa, adjusting the reaction temperature to 50-60 ℃, and performing pressure-maintaining and heat-preserving reaction;
(3) when the content of the intermediate product dihydroionone in the high-pressure reaction kettle is less than or equal to 2 percent, stopping adding hydrogen into the high-pressure reaction kettle, stopping heating the materials in the high-pressure reaction kettle, replacing the hydrogen in the high-pressure reaction kettle with nitrogen, and stopping the reaction;
(4) after the materials in the high-pressure reaction kettle are cooled, settling, filtering and discharging to obtain a mixture of the tetrahydro ionone and the solvent;
(5) adding the mixture of the tetrahydro ionone and the solvent into a distillation kettle, and distilling to recover the solvent to obtain tetrahydro ionone;
the stabilizer is triethanolamine;
the Raney nickel catalyst is model RTH3110 Ni.
2. The process for producing tetrahydroionones according to claim 1, wherein in the step (5), the solvent is recovered by initially performing atmospheric distillation and the solvent content in the tank is monitored;
when the content of the solvent in the distillation kettle is less than or equal to 10%, adjusting the pressure in the distillation kettle to 20-30 kPa, adjusting the temperature in the distillation kettle to 100-110 ℃, and continuing to distill and recover the solvent;
when the content of the solvent in the distillation kettle is less than or equal to 3%, adjusting the pressure in the distillation kettle to 3-10 kPa, and adjusting the temperature in the distillation kettle to 110-120 ℃;
and when the content of the solvent in the distillation kettle is less than or equal to 0.5 percent, stopping heating the materials in the distillation kettle, reducing the temperature in the kettle to normal temperature, replacing the air in the kettle with nitrogen, filtering, and discharging to obtain the tetrahydro ionone.
3. The method for preparing tetrahydro ionone according to claim 1, wherein the ionone is synthetic or natural and has a content of 95% or more.
4. The method for preparing tetrahydro ionone according to claim 1, 2 or 3, wherein the mass ratio of the ionone, the raney nickel catalyst, the solvent and the stabilizer is 1: 0.01-0.03: 1.6-2.2: 0.002-0.005.
5. The method according to claim 1, wherein the solvent is ethanol.
6. The method according to claim 1, wherein the raney nickel catalyst obtained after filtration in step (4) is repeatedly used in the reaction of the next batch.
7. The process for producing tetrahydroionones according to claim 1, wherein in the step (5), the solvent recovered by distillation is repeatedly used in the reaction of the next batch.
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| CN111871429B (en) * | 2020-08-28 | 2022-07-12 | 万华化学集团股份有限公司 | Raney catalyst and preparation method thereof, and method for preparing gamma-ketene from alpha, gamma-dienone |
| CN113773170A (en) * | 2021-09-15 | 2021-12-10 | 苏州敬业医药化工有限公司 | Preparation method of 4-methyl-2-pentanol |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1212902A (en) * | 1998-09-14 | 1999-04-07 | 中国科学院广州化学研究所 | Method preparation of compound catalyst with selective preparation of dihydro-beta-irisone |
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Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1212902A (en) * | 1998-09-14 | 1999-04-07 | 中国科学院广州化学研究所 | Method preparation of compound catalyst with selective preparation of dihydro-beta-irisone |
Non-Patent Citations (2)
| Title |
|---|
| Chemoselective Hydrogenation of the Olefinic Bonds Using a Palladium/Magnesium-Lanthanum Mixed Oxide Catalyst;Mannepalli Lakshmi Kantam等;《Adv. Synth. Catal.》;20121231;第354卷;663-669 * |
| Layered double hydroxides supported nano palladium: An efficient catalyst for the chemoselective hydrogenation of olefinic bonds;Lakshmi Kantam M∗等;《Journal of Molecular Catalysis A: Chemical》;20121231;第365卷;115-119 * |
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