CN113773185A - Preparation method of 3, 6-dimethoxy-2, 7-dimethyl-4-octenedialdehyde - Google Patents
Preparation method of 3, 6-dimethoxy-2, 7-dimethyl-4-octenedialdehyde Download PDFInfo
- Publication number
- CN113773185A CN113773185A CN202111060892.0A CN202111060892A CN113773185A CN 113773185 A CN113773185 A CN 113773185A CN 202111060892 A CN202111060892 A CN 202111060892A CN 113773185 A CN113773185 A CN 113773185A
- Authority
- CN
- China
- Prior art keywords
- reaction
- acid
- product
- dimethyl
- reaction kettle
- 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.)
- Granted
Links
Classifications
-
- 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
- C07C45/51—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by pyrolysis, rearrangement or decomposition
- C07C45/511—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by pyrolysis, rearrangement or decomposition involving transformation of singly bound oxygen functional groups to >C = O groups
- C07C45/513—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by pyrolysis, rearrangement or decomposition involving transformation of singly bound oxygen functional groups to >C = O groups the singly bound functional group being an etherified hydroxyl group
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a preparation method of 3, 6-dimethoxy-2, 7-dimethyl-4-octenedialdehyde, and the product prepared by the process can be directly used as a raw material for synthesizing C10 dialdehyde, and has high conversion rate of the raw material and high reaction selectivity. The reaction does not need to add an organic solvent, has small three-waste content, is green and environment-friendly, and the prepared product has good fluidity, low viscosity and thermal stability.
Description
Technical Field
The invention belongs to the technical field of chemical synthesis, and particularly relates to a preparation method of 3, 6-dimethoxy-2, 7-dimethyl-4-octenedialdehyde.
Background
3, 6-dimethoxy-2, 7-dimethyl-4-octenedial is a key intermediate for synthesizing 2, 7-dimethyl-2, 4, 6-octatriene-1, 8-dialdehyde (C10 dialdehyde for short), and C10 dialdehyde is a main raw material for synthesizing beta-carotene, canthaxanthin, astaxanthin and lycopene, so 3, 6-dimethoxy-2, 7-dimethyl-4-octenedial has been paid attention as an important chemical raw material.
The 3, 6-dimethoxy-2, 7-dimethyl-4-octenedial (hereinafter referred to as acidolysis product) is prepared by the acetal cleavage reaction of 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene (hereinafter referred to as adduct) which is mainly used as a raw material under the action of an acid catalyst.
Patent CN101234957A uses sulfuric acid as catalyst to catalyze 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene to carry out acidolysis to obtain acidolysis product, however, the acidolysis product generated by the method contains a large amount of impurities, the system fluidity is deteriorated due to the high content of the impurities, and the viscosity of the generated acidolysis product 3, 6-dimethoxy-2, 7-dimethyl-4-octene dialdehyde is high, which is not beneficial to storage and sale of the product.
Therefore, the development of a production process with high conversion rate, high selectivity, simple operation process and environmental protection is key for synthesizing 3, 6-dimethoxy-2, 7-dimethyl-4-octenedial and synthesizing C10 dialdehyde by subsequent reaction.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides a preparation method of 3, 6-dimethoxy-2, 7-dimethyl-4-octenedialdehyde, which improves the reaction selectivity and the conversion rate of raw materials by controlling the generation amount of reaction intermediates, and the prepared acidolysis product has good fluidity, room temperature viscosity of less than 50cP, good thermal stability and good commercial competitiveness.
The applicant researches and discovers that 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene has intermediate products in the process of acidolysis reaction of 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene dialdehyde in the presence of acid catalysis
The content of the half acidolysis product affects the quality of the acidolysis product formed by the reaction.
The acidolysis reaction of 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octenedial to produce 3, 6-dimethoxy-2, 7-dimethyl-4-octenedial has the following reaction route:
based on the above findings, the present application provides a method for preparing 3, 6-dimethoxy-2, 7-dimethyl-4-octenedialdehyde, wherein, 1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene is subjected to acidolysis reaction under the action of acid catalyst, the mass content of the intermediate product is controlled to be 1-20%, preferably 1.2-17%, during the reaction process, and the intermediate product is:
the mass content of the intermediate product is equal to the mass of the intermediate product per the amount of 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene added.
The applicant researches and discovers that in the acidolysis process of 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene under acid catalysis, the reaction rate of the generated half acidolysis product is greater than that of the generated half acidolysis product, and as the reaction proceeds, if the content of the half acidolysis product in the reaction process is excessive, more side reactions occur, so that the finally generated acidolysis product contains a large amount of impurities and the yield of the acidolysis product is influenced; the applicant of the present invention unexpectedly finds that by controlling the content of the intermediate product (i.e. the half acidolysis product) in the reaction process within a specific range, not only can the occurrence of side reactions be effectively reduced, but also the viscosity of the prepared acidolysis product can be reduced, the thermal stability can be improved, and the product has strong exterior sales competitiveness.
In some preferred embodiments of the present invention, the preparation method further comprises the steps of: mixing raw materials 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene and an acid catalyst, reacting at a certain temperature and pressure, and introducing steam into the reaction for gas stripping.
In some particularly preferred embodiments of the present invention, first, the reaction kettle is heated to the reaction temperature, then the raw materials 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene and acid catalyst are added under stirring, the reaction kettle is adjusted to the reaction pressure, steam is introduced for stripping, and the reaction is stopped after a period of time.
The water vapor introduced into the reaction kettle carries by-product alcohol products to flow out of the top of the reaction kettle to the rectifying tower for separation, the by-product is obtained at the top of the rectifying tower, and the condensed water vapor in the tower kettle can be introduced into the reaction kettle again for gas stripping and recycling.
In some preferred embodiments of the present invention, the reaction temperature ranges from 50 ℃ to 150 ℃, preferably from 80 ℃ to 100 ℃.
Preferably, the reaction stirring speed is 100 to 1000rpm, more preferably 200 to 500 rpm.
Preferably, the reaction pressure is from negative pressure to slightly positive pressure, more preferably from 10kPaA to 1.1MPaG, and still more preferably from 20kPaA to 0.1 MPaG.
Preferably, the reaction time is 0.1-5 h, preferably 1-3 h.
Preferably, the acid catalyst is one or more of an inorganic acid, an acid salt of a polybasic acid, a Lewis acid or an organic acid, the inorganic acid comprises sulfuric acid, nitric acid, phosphoric acid, boric acid or a hydrohalic acid, the acid salt of a polybasic acid comprises sodium bisulfate, sodium hydrogen phosphate, disodium hydrogen phosphate, and the Lewis acid comprises FeCl3、ZnCl2And AlCl3And the like, the organic acids include benzenesulfonic acid, toluenesulfonic acid and oxalic acid, adipic acid and the like, preferably oxalic acid;
preferably, the amount of the acid catalyst is 0.1 to 10 wt%, more preferably 1 to 5 wt%, based on the mass of 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene.
In the invention, the water vapor is the vaporized gas of deionized water at the reaction temperature, and a gas distributor is added at the bottom of the reaction kettle in order to uniformly disperse the gas in the reaction liquid. The addition of the water vapor can not only control the reaction temperature, but also continuously remove the reaction byproducts of methanol and ethanol, thereby controlling the reaction degree, being beneficial to ensuring that the content of the obtained intermediate product is in the range of 1-20 percent, further improving the reaction conversion rate and selectivity, reducing the occurrence of side reactions and improving the product purity.
Preferably, the volume flow rate of the water vapor is 10-1000 mL/h, and preferably 100-500 mL/h.
Preferably, the separation conditions of the rectifying tower are as follows: the temperature is 50-100 ℃, preferably 75-95 ℃, and the pressure is 0.05-1.1 MPaG, preferably 0.1-0.2 MPaG.
The invention has the beneficial effects that:
(1) the applicant of the invention discovers the influence of the content of a reaction intermediate product, namely a half acidolysis product, on the product performance for the first time through a great deal of research, and proposes a method for improving the product performance by controlling the content of the intermediate product for the first time. The preparation method can accurately control the temperature of the reaction system and the content of the intermediate, so that the product prepared by the process has high yield and less impurity content, the product generated by the reaction can be directly used as a raw material for synthesizing C10 dialdehyde, the reaction selectivity is more than 96 percent, and the conversion rate of the raw material can reach more than 99 percent.
(2) The reaction does not need to add an organic solvent, has extremely low three-waste content and is green and environment-friendly.
(3) The acidolysis product 3, 6-dimethoxy-2, 7-dimethyl-4-octenedial prepared by the method has good fluidity, room temperature viscosity of less than 50cP, good thermal stability, high storage stability and good commercial competitiveness.
Detailed Description
The invention adopts a high performance liquid chromatograph to analyze the content of raw materials and products, Agilent LC-1200 and a chromatographic workstation data processing system Chomatopac C-RIA. Chromatographic conditions are as follows: the mobile phase was a methanol/acetonitrile 9/1(v/v) mixture, the detection temperature was 40 ℃, the flow rate was 1mL/min, and the wavelength was 328 nm. Namely, the product composition is qualitatively and quantitatively analyzed according to the external standard method of the conditions specified in GB 14750-2010.
The raw material 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene used in the invention is purchased from Basff chemical company Limited, and oxalic acid is purchased from Aladdin reagent company Limited.
Intermediate product
By nuclear magnetic characterization, the nuclear magnetic hydrogen spectrum is:
HNMR(DMSO,400M Hz)δ＝1.03(d,3H),1.19(d,3H),2.69(m,1H),2.98(m,1H),3.36(s,6H)，3.68(s,6H)，3.81(d,1H)，4.14(d,1H)，4.28(d,1H),5.96(s,2H)，8.56(d,1H)。
in the examples, the acidolysis by-products were:
the water vapor is the vaporized gas of deionized water at the reaction temperature, and a gas distributor is added at the bottom of the reaction kettle in order to uniformly disperse the gas in the reaction liquid.
The mass content of the intermediate product is equal to the mass of the intermediate product per mass of 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene added.
Example 1:
heating a 1L reaction kettle to 80 ℃, setting the stirring speed at 200rpm, adding 320.4g of 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene into the reaction kettle under the stirring state, pumping the reaction kettle to 47.3kPaA, adding 3.2g of oxalic acid into the reaction kettle, introducing 100mL/h of water vapor into the reaction kettle, introducing a steam mixture at the top of the reaction kettle into a refining tower in time during the reaction process, separating alcohol substances and water vapor at 75 ℃ and 0.1MPaG, stopping stirring and introducing steam after reacting for 1h, and finishing the reaction.
Sampling is carried out at intervals of 10min in the reaction process, the mass contents of intermediate half acidolysis products in the reaction liquid are analyzed to be 5.4% (10min), 10.5% (20min), 18.4% (30min), 9.7% (40min), 5.2% (50min) and 2.9% (60min), and the intermediate content is 2.9-18.4%. The temperature change of the reaction kettle is monitored to be 79-81 ℃ in the reaction process, the conversion rate of the raw material addition product is analyzed by liquid phase after the reaction is finished to be 98.5%, the selectivity of the target product is 97.5%, the content of the acidolysis by-product in the product is 0.045%, and the content of the semi-acidolysis product is 2.9%.
Taking the reaction product, measuring the viscosity of the system at 25 ℃ to be 35cP, storing the reaction product for 7 days at 30 ℃ in a nitrogen atmosphere, and enabling the deterioration rate of the product to be 0.05%/d.
Example 2:
heating a 1L reaction kettle to 85 ℃, setting the stirring speed at 300rpm, adding 320.4g of the adduct into the reaction kettle under the stirring state, pumping the reaction kettle to 57.8kPaA, adding 6.4g of oxalic acid into the reaction kettle, introducing 200mL/h of water vapor from the bottom of the reaction kettle, introducing a steam mixture at the top of the reaction kettle into a refining tower in time during the reaction process, separating alcohol substances and water vapor at 79 ℃ and 0.1MPaG, stopping stirring and stopping introducing the steam after reacting for 2h, and finishing the reaction.
Sampling is carried out at intervals of 20min in the reaction process, the mass contents of intermediate half acidolysis products in the reaction liquid are analyzed to be 6.8 percent (20min), 12.5 percent (40min), 14.7 percent (60min), 19.8 percent (80min), 9.6 percent (100min) and 1.4 percent (120min), and the intermediate content is 1.4 to 19.8 percent. The temperature change of the reaction kettle is monitored to be 83-86 ℃ in the reaction process, the conversion rate of liquid phase analysis raw materials is 99.2 percent after the reaction is finished, the selectivity of a target product is 96.3 percent, the content of acidolysis by-products in the product is 0.062 percent, and the content of semi-acidolysis products is 1.4 percent.
The reaction product is taken out, the viscosity of the system is measured to be 40cP at 25 ℃, the reaction product is stored for 7 days in a nitrogen atmosphere at 30 ℃, and the deterioration rate of the product is 0.08%/d.
Example 3:
heating a 1L reaction kettle to 90 ℃, setting the stirring speed at 400rpm, adding 320.4g of the adduct into the reaction kettle under the stirring state, pumping the reaction kettle to 70.1kPaA, adding 9.6g of oxalic acid into the reaction kettle, introducing 300mL/h of water vapor into the reaction kettle from the bottom of the reaction kettle, introducing a steam mixture at the top of the reaction kettle into a refining tower in time during the reaction process, separating alcohol substances and water vapor at 83 ℃ and 0.15MPaG, stopping stirring and stopping introducing the steam after reacting for 3h, and finishing the reaction.
Sampling is carried out at intervals of 30min in the reaction process, the content of the intermediate half acidolysis product in the reaction solution is analyzed to be 9.8 percent (30min), 12.5 percent (60min), 15.7 percent (90min), 17.5 percent (120min), 6.5 percent (150min) and 1.6 percent (180min), and the content of the intermediate is 3.6 to 17.5 percent. The temperature change of the reaction kettle is monitored to be 88-92 ℃ in the reaction process, the conversion rate of liquid phase analysis raw materials is 99.5 percent after the reaction is finished, the selectivity of a target product is 98.4 percent, the content of acidolysis by-products in the product is 0.044 percent, and the content of semi-acidolysis products is 1.6 percent.
The reaction product is taken out, the viscosity of the system is measured to be 26cP at 25 ℃, the reaction product is stored for 7 days in a nitrogen atmosphere at 30 ℃, and the deterioration rate of the product is 0.048%/d.
Example 4:
heating a 1L reaction kettle to 95 ℃, setting the stirring speed at 450rpm, adding 320.4g of the adduct into the reaction kettle under the stirring state, pumping the reaction kettle to 84.5kPaA, adding 12.8g of oxalic acid into the reaction kettle, introducing 400mL/h of water vapor from the bottom of the reaction kettle, introducing a steam mixture at the top of the reaction kettle into a refining tower in time during the reaction process, separating alcohol substances and water vapor at 88 ℃ and 0.20MPaG, stopping stirring and stopping introducing the steam after reacting for 2h, and finishing the reaction.
Sampling is carried out at intervals of 20min in the reaction process, the content of the intermediate half acidolysis product in the reaction solution is analyzed to be 9.8 percent (20min), 15.5 percent (40min), 16.7 percent (60min), 12.6 percent (80min), 5.6 percent (100min) and 1.2 percent (120min), and the content of the intermediate is 1.2 to 16.7 percent. The temperature change of the reaction kettle is monitored to be 94-97 ℃ in the reaction process, the conversion rate of liquid phase analysis raw materials is 99.9 percent after the reaction is finished, the selectivity of a target product is 97.4 percent, the content of acidolysis by-products in the product is 0.094 percent, and the content of semi-acidolysis products is 1.2 percent.
The reaction product was stored at 25 ℃ for 7 days in a nitrogen atmosphere at 30 ℃ with a system viscosity of 20cP and a product deterioration rate of 0.073%/d.
Example 5:
heating a 1L reaction kettle to 100 ℃, setting the stirring speed at 500rpm, adding 320.4g of the adduct into the reaction kettle under the stirring state, pumping the reaction kettle to 84.5kPaA, adding 16.0g of oxalic acid into the reaction kettle, introducing 500mL/h of water vapor into the reaction kettle from the bottom of the reaction kettle, introducing a steam mixture at the top of the reaction kettle into a refining tower in time during the reaction process, separating alcohol substances and water vapor at 95 ℃ and 0.20MPaG, stopping stirring and stopping introducing the steam after reacting for 1h, and finishing the reaction.
Sampling is carried out at intervals of 10min in the reaction process, the content of the intermediate half acidolysis product in the reaction solution is analyzed to be 11.3 percent (10min), 13.5 percent (20min), 14.8 percent (30min), 9.7 percent (40min), 4.4 percent (50min) and 1.6 percent (60min), and the content of the intermediate is 1.6 to 14.8 percent. The temperature change of the reaction kettle is monitored to be 98-102 ℃ in the reaction process, the conversion rate of liquid phase analysis raw materials is 100 percent after the reaction is finished, the selectivity of a target product is 96.2 percent, the content of acidolysis by-products in the product is 0.11 percent, and the content of half acidolysis products is 1.6 percent.
Taking the reaction product, measuring the viscosity of the system at 25 ℃ to be 12cP, storing the reaction product for 7 days at 30 ℃ in a nitrogen atmosphere, and enabling the deterioration rate of the product to be 0.11%/d.
Comparative example 1:
heating a 1L reaction kettle to 80 ℃, setting the stirring speed at 200rpm, adding 320.4g of the adduct into the reaction kettle under the stirring state, pumping the reaction kettle to 47.3kPaA, adding 3.2g of oxalic acid into the reaction kettle, reacting for 1h, stopping stirring, and finishing the reaction.
Sampling is carried out at intervals of 10min in the reaction process, the content of intermediate half acidolysis products in the reaction solution is analyzed to be 15.3% (10min), 21.5% (20min), 30.5% (30min), 26.9% (40min), 19.9% (50min) and 10.8% (60min), the content of the intermediate is 15.3% -30.5%, the conversion rate of raw materials is analyzed to be 86.9% by liquid phase after the reaction is finished, the selectivity of target products is 90.1%, the content of acidolysis by-products in the products is 0.69%, the content of half addition products is 10.8%, and the system is a uniform organic phase after the reaction is finished.
The viscosity of the system measured by taking the reaction product at 25 ℃ is 147cP, the product is stored for 7 days in a nitrogen atmosphere at 30 ℃, the deterioration rate of the product is 1.55%/d, and the storage stability is poor.
As can be seen from the comparative examples, when the content of the intermediate product is too high in the system, the conversion rate of the raw material and the selectivity of the target product are both reduced, side reactions are increased, resulting in increased side reactions of the reaction, increased impurity content, and poor storage stability of the product.
Comparative example 2:
heating a 1L reaction kettle to 80 ℃, setting the stirring speed at 200rpm, adding 320.4g of 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene into the reaction kettle under the stirring state, pumping the reaction kettle to 47.3kPaA, adding 3.2g of oxalic acid into the reaction kettle, introducing 500mL/h of water vapor into the reaction kettle, introducing a steam mixture at the top of the reaction kettle into a refining tower in time during the reaction process, separating alcohol substances and water vapor at 75 ℃ and 0.1MPaG, stopping stirring and introducing steam after reacting for 1h, and finishing the reaction.
Sampling is carried out at intervals of 10min in the reaction process, the mass contents of intermediate half acidolysis products in the reaction liquid are analyzed to be 0.02% (10min), 0.08% (20min), 0.25% (30min), 0.67% (40min), 0.95% (50min) and 0.64% (60min), and the intermediate content is 0.02-0.95%. The temperature change of the reaction kettle is monitored to be 82-84 ℃ in the reaction process, the conversion rate of the raw material addition product is analyzed by liquid phase after the reaction is finished to be 99.6%, the selectivity of the target product is 80.5%, the content of the acidolysis by-product in the product is 10.6%, and the content of the semi-acidolysis product is 0.88%.
Taking the reaction product, measuring the viscosity of the system at 25 ℃ to be 226cP, storing the reaction product for 7 days at 30 ℃ in a nitrogen atmosphere, and enabling the deterioration rate of the product to be 1.12%/d.
As can be seen from the comparative examples, when the content of the intermediate product was too low in the system, the conversion of the raw material was not decreased, but the selectivity of the objective product was decreased, the content of the acid hydrolysis by-product was significantly increased, the content of impurities was increased, the storage stability of the product was poor, the fluidity was poor, the product agglomerated at room temperature, and almost no fluidity was observed.
It was also found during the experiment that the sharp increase of the acidolysis by-products significantly decreased the colorimetric value of the product, which exhibited a dark yellow color different from that in example 1. Greatly reducing the appearance and the sale competitiveness of the product.
Claims (7)
1. A preparation method of 3, 6-dimethoxy-2, 7-dimethyl-4-octenedialdehyde is characterized in that 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene as a raw material is subjected to acidolysis reaction under the action of an acid catalyst, the mass content of an intermediate product is controlled to be 1-20%, preferably 1.2-17%, in the reaction process, and the intermediate product is:
2. the method of claim 1, further comprising the steps of: mixing raw materials 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene and an acid catalyst, reacting at a certain temperature and pressure, and introducing steam into the reaction for gas stripping.
3. The method of manufacturing according to claim 1 or 2, comprising the steps of: firstly, heating a reaction kettle to a reaction temperature, then adding raw materials 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene and an acid catalyst under a stirring state, adjusting the reaction kettle to a reaction pressure, introducing steam for stripping, and stopping the reaction after a period of reaction time.
4. The method of any one of claims 1 to 3, wherein the reaction temperature is in the range of 50 ℃ to 150 ℃, preferably 80 ℃ to 100 ℃;
preferably, the reaction stirring speed is 100-1000 rpm, more preferably 200-500 rpm;
preferably, the reaction pressure is from negative pressure to slightly positive pressure, more preferably from 10kPaA to 1.1MPaG, and further preferably from 20kPaA to 0.1 MPaG;
preferably, the reaction time is 0.1-5 h, preferably 1-3 h;
preferably, the acid catalyst is one or more of an inorganic acid, an acid salt of a polybasic acid, a Lewis acid or an organic acid, the inorganic acid comprises sulfuric acid, nitric acid, phosphoric acid, boric acid or a hydrohalic acid, the acid salt of a polybasic acid comprises sodium bisulfate, sodium hydrogen phosphate, disodium hydrogen phosphate, and the Lewis acid comprises FeCl3、ZnCl2And AlCl3The organic acid comprises benzene sulfonic acid, toluene sulfonic acid, oxalic acid and adipic acid, and preferably oxalic acid.
5. The process according to any one of claims 1 to 4, wherein the acid catalyst is used in an amount of 0.1 to 10 wt%, more preferably 1 to 5 wt%, based on the mass of 1,1,3,6,8, 8-hexamethoxy-2, 7-dimethyl-4-octene.
6. The method according to any one of claims 1 to 5, wherein the volume flow rate of the water vapor is 10 to 1000mL/h, preferably 100 to 500 mL/h.
7. The preparation method of any one of claims 1 to 6, wherein the steam introduced into the reaction kettle entrains byproducts to flow out of the top of the reaction kettle to the rectifying tower for separation, and the separation conditions of the rectifying tower are as follows: the temperature is 50-100 ℃, preferably 75-95 ℃, and the pressure is 0.05-1.1 MPaG, preferably 0.1-0.2 MPaG.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111060892.0A CN113773185B (en) | 2021-09-10 | 2021-09-10 | Preparation method of 3, 6-dimethoxy-2, 7-dimethyl-4-octenedialdehyde |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111060892.0A CN113773185B (en) | 2021-09-10 | 2021-09-10 | Preparation method of 3, 6-dimethoxy-2, 7-dimethyl-4-octenedialdehyde |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113773185A true CN113773185A (en) | 2021-12-10 |
| CN113773185B CN113773185B (en) | 2022-08-05 |
Family
ID=78842433
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111060892.0A Active CN113773185B (en) | 2021-09-10 | 2021-09-10 | Preparation method of 3, 6-dimethoxy-2, 7-dimethyl-4-octenedialdehyde |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113773185B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101234957A (en) * | 2008-03-11 | 2008-08-06 | 浙江大学 | Method for synthesizing 2,7-dimethyl-octa-2,4,6-trienedial |
| WO2013186550A1 (en) * | 2012-06-11 | 2013-12-19 | University Of Bristol | Compound and method |
-
2021
- 2021-09-10 CN CN202111060892.0A patent/CN113773185B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101234957A (en) * | 2008-03-11 | 2008-08-06 | 浙江大学 | Method for synthesizing 2,7-dimethyl-octa-2,4,6-trienedial |
| WO2013186550A1 (en) * | 2012-06-11 | 2013-12-19 | University Of Bristol | Compound and method |
| US20150158837A1 (en) * | 2012-06-11 | 2015-06-11 | University Of Bristol | Compound And Method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113773185B (en) | 2022-08-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113201016A (en) | Preparation method of C15 phosphonium salt | |
| CN113773185B (en) | Preparation method of 3, 6-dimethoxy-2, 7-dimethyl-4-octenedialdehyde | |
| CN109369342B (en) | Preparation method of high-purity aluminum isopropoxide | |
| CN110590508A (en) | Separation method of medium-low temperature coal tar 2,4/2, 5-mixed xylenol | |
| CN106631732B (en) | Synthetic method of 4-hydroxy-2-butanone | |
| CN116640047A (en) | Preparation method of 4-hydroxy biphenyl | |
| CN108586243B (en) | Method for indirectly synthesizing organic carbonate from carbon dioxide and organic amine | |
| CA2191300C (en) | Process for the preparation of camphene by the rearrangement of .alpha.-pinene | |
| CN111349008B (en) | Method for preparing glyoxylic acid | |
| CN108863717A (en) | A method of efficiently preparing alkynol | |
| CN109896924B (en) | Preparation method of 3-methyl-2-pentene-4-alkyne-1-alcohol | |
| US3873587A (en) | Production of peroxytitanium complexes from organic hydroperoxides | |
| CN106588584A (en) | Dehydration method for ether solvent | |
| CN115850033B (en) | Synthesis method of guaiacol | |
| CN113735693B (en) | Synthesis method of resveratrol dimethyl ether | |
| CN113429284B (en) | Synthetic method of 3, 5-dichlorobenzoyl chloride | |
| CN114292163B (en) | Method for preparing isopulegol from citronellal | |
| CN112538008B (en) | Synthetic method of difluoroacetic acid | |
| US3527829A (en) | Process for producing high-purity isobutylene | |
| CN115286506B (en) | Method for synthesizing matrithrin by one-step oxidation esterification with metal organic framework material as catalyst | |
| CN113896634B (en) | Preparation method of 3-methoxy methyl acrylate | |
| TW202000636A (en) | Process for preparing bis(2-hydroxyethyl) terephthalate | |
| CN114605244B (en) | Preparation method of cyclopentyl formaldehyde | |
| CN115850047B (en) | Method for controlling process stability of pseudo ionone | |
| CN117244564A (en) | Catalyst system and method for preparing cyclohexanol by using same |
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 |