Continuous production process of E-conjugated diene alcohol ester compound
By employing a continuous production unit with multiple tubular reactors and mixers in the production of E-conjugated dienol esters, the problems of low efficiency and poor safety in existing technologies have been solved, achieving efficient and safe production results.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- MODERN TEXTILE TECH INNOVATION CENT (JIANHU LAB)
- Filing Date
- 2025-12-17
- Publication Date
- 2026-05-12
AI Technical Summary
Existing production processes for E-conjugated dienol esters suffer from low efficiency, poor safety, high equipment investment, and low yield. In particular, insufficient heat exchange and mixing in batch production lead to increased side reactions, and microchannel reactors are prone to clogging and are difficult to scale up.
A continuous production unit consisting of multiple tubular reactors and mixers connected in series or parallel uses premixing and tubular reactors to enhance the mixing of the reaction liquid, rapidly removes heat, and uses specific alkali, aldehyde, and acyl chloride solutions to carry out continuous reactions at controlled temperatures.
It enables efficient and safe continuous production of E-conjugated dienol esters, improving production efficiency and yield, reducing equipment investment, and avoiding the drawbacks of intermittent production.
Smart Images
Figure CN122010729A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of organic chemical engineering, and in particular relates to a continuous production process for E-conjugated dienol ester compounds. Background Technology
[0002] E-conjugated dienol esters are key intermediates providing high stereoselectivity and multifunctionality in fields such as organic synthesis and materials chemistry. They can be polymerized to form polymers with double bonds in their main chain. Chinese patent CN104031191A discloses the wide applications of polymers with double bonds in their main chain in the polymer field. For example, the double bonds can be further polymerized to form cross-linked or hyperbranched polymers, or the polymers can be functionalized through further chemical reactions.
[0003] E-conjugated dienol esters are typically produced using batch processing. In this process, the alkali solution is first cooled to the reaction temperature, then the unsaturated aldehyde solution is slowly added dropwise to the alkali solution. After the reaction is complete, the acyl chloride solution is then slowly added dropwise. Batch production is time-consuming, complex, and inefficient. The reaction between unsaturated aldehydes and acyl chlorides is strongly exothermic, and the side reactions compete with the main reaction. Therefore, the degree of heat exchange and micro-mixing in the reaction process significantly affects the yield of the target product. Enhancing the heat exchange and mixing process is beneficial to the main reaction. Batch reactors have limited heat and mass transfer, resulting in a significant decrease in product yield and increased safety risks such as temperature runaway. Neier et al. (Synthesis 2007, 15, 2379–2387x) reported a method for synthesizing E-conjugated dienol esters using crotonaldehyde and different types of acyl chlorides. This method employs a batch dropwise addition operation in a still pan, with product selectivity ranging from 53% to 81%. Zhu et al. (Org. Lett. 2023, 25, 3573−3577) reported a method for synthesizing E-conjugated dienol esters using acetylene and different types of acyl chlorides. This method has the advantages of high selectivity and high atom economy, but the rhodium-based catalyst used is relatively expensive and difficult to achieve industrial production.
[0004] Chinese patents CN 221208000U and CN 114773241A disclose a method for continuous synthesis of carboxylic acid esters using a microchannel reactor. However, microchannel reactors have disadvantages such as low throughput, easy clogging, high equipment investment, and difficulty in scale-up. Furthermore, the synthesis of E-conjugated dienol esters requires extremely low temperatures (usually below -20 °C), and water or other impurities in the reaction solution are prone to exist in solid form, which can clog the microchannels. Summary of the Invention
[0005] The purpose of this invention is to overcome the shortcomings of the above-mentioned production processes for E-conjugated dienol esters and to provide a safe, efficient, simple, easy-to-scale, low-investment, and high-yield continuous production process for E-conjugated dienol esters.
[0006] The technical solution adopted in this invention is as follows: A continuous production process for E-conjugated dienol esters includes the following steps: (1) The alkaline solution is transferred to the first reactor and cooled to the reaction temperature; (2) The alkaline solution cooled in step (1) is transported to the first mixer for mixing with the aldehyde solution, and the mixture is then transported to the second reactor for reaction; (3) The reaction solution from step (2) is mixed with the acyl chloride solution through a second mixer and then transported to a third reactor to react, thereby preparing E-conjugated dienol ester compounds.
[0007] Further settings include: The alkaline solution is selected from any one of potassium hydroxide, sodium hydroxide, sodium hydrogen, potassium hydrogen, sodium ethoxide, potassium ethoxide, sodium n-butoxide, potassium n-butoxide, sodium tert-butoxide, potassium tert-butoxide, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, or tetrahydrofuran solution.
[0008] The aldehyde solution is selected from any one of dimethyl sulfoxide, dimethylformamide, dimethylacetamide, or tetrahydrofuran solutions of α,β-unsaturated aldehydes.
[0009] The acyl chloride solution is selected from any one of the following: aliphatic or aromatic acyl chloride solutions: dimethyl sulfoxide, dimethylformamide, dimethylacetamide, or tetrahydrofuran.
[0010] The reaction equation is as follows:
[0011] Where: R1, R2, R ３ It can be any one of the following: hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, heterocyclic or oxygen / nitrogen-containing groups.
[0012] The first reactor, the second reactor, and the third reactor are single tubular reactors, or multiple tubular reactors connected in series or in parallel.
[0013] The first mixer and the second mixer are selected from any one of the following: a T-type mixer, a Y-type mixer, and a Venturi mixer.
[0014] In step (1), the cooling temperature is -80℃ to -20℃, and the residence time in the first reactor is 5-20 minutes. Preferably, the cooling temperature is -40℃, and the residence time in the first reactor is 5 minutes.
[0015] In step (2), the reaction temperature is -80℃ to -20℃, and the residence time in the second reactor is 5-20 minutes. Preferably, the reaction temperature is -80℃ and the residence time in the second reactor is 10 minutes.
[0016] In step (3), the reaction temperature is -80℃ to -20℃, and the residence time in the second reactor is 5-20 minutes. Preferably, the reaction temperature is -80℃ and the residence time in the second reactor is 20 minutes.
[0017] This invention also provides a continuous production apparatus for E-conjugated dienol esters, characterized in that it includes a first reactor, a second reactor, and a third reactor, wherein the first reactor, the second reactor, and the third reactor are connected in series. The first reactor and the second reactor are connected by a first mixer, and the second reactor and the third reactor are connected by a second mixer. The first liquid storage tank is connected to the first reactor via a first fluid transfer pump. The first liquid storage tank, the first fluid transfer pump, and the first reactor together constitute the first reaction unit. The second liquid storage tank is connected to the first mixer via a second fluid transfer pump. The second liquid storage tank, the second fluid transfer pump, the first mixer, and the second reactor constitute the second reaction unit. The third storage tank is connected to the second mixer via a third fluid transfer pump. The third storage tank, the third fluid transfer pump, the second mixer, and the third reactor together form the third reaction unit. The first storage tank is used to store the first reaction solution, which is an alkaline solution selected from any one of potassium hydroxide, sodium hydroxide, sodium hydrogen, potassium hydrogen, sodium ethoxide, potassium ethoxide, sodium n-butoxide, potassium n-butoxide, sodium tert-butoxide, potassium tert-butoxide, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, or tetrahydrofuran solution. The second storage tank is used to store the second reaction solution, which is an aldehyde solution selected from any one of dimethyl sulfoxide, dimethylformamide, dimethylacetamide or tetrahydrofuran solution of α,β-unsaturated aldehydes. The third storage tank is used to store the third reaction solution, which is an acyl chloride solution selected from any one of aliphatic or aromatic acyl chlorides, such as dimethyl sulfoxide, dimethylformamide, dimethylacetamide, or tetrahydrofuran solution.
[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) This invention provides an efficient continuous production process for E-conjugated dienol ester compounds, which has higher production efficiency and improved production safety compared with traditional batch reactors.
[0019] (2) The present invention provides a continuous production apparatus for E-conjugated dienol ester compounds. The continuous production apparatus includes multiple reactors, mixers and storage tanks connected in series or in parallel, forming multiple reaction units. It adopts premixing and tubular reactors, which enhances the mixing between reaction liquids, can quickly remove the heat generated by the reaction, save reaction time, and improve the yield of the target product. Attached Figure Description
[0020] Figure 1 This is a schematic diagram of the continuous production apparatus for E-conjugated dienol ester compounds of the present invention.
[0021] Figure 2 The image shows the hydrogen NMR spectrum of the product prepared in Example 1 of this invention. Detailed Implementation
[0022] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited thereto. Unless otherwise specified, the raw materials and reagents used in the present invention are all prior art or commercially available products.
[0023] The reaction described in this embodiment of the invention is carried out in a continuous production apparatus, the structure of which is as follows: Figure 1 As shown, it includes a first reactor 1, a second reactor 2, and a third reactor 3, which are connected in series.
[0024] The first reactor 1, the second reactor 2, and the third reactor 3 can be a single tubular reactor, or multiple tubular reactors connected in series or parallel. As an example, in the following embodiments, the first reactor 1, the second reactor 2, and the third reactor 3 are all single tubular reactors.
[0025] In a preferred embodiment, the tubular reactor is a packed bed tubular reactor, with packing material or flow-blocking plates inside the reactor to enhance the contact mixing of the reaction liquid.
[0026] In a preferred embodiment, the tubular reactor is equipped with a temperature control device, which is a heat exchange jacket located on the outside of the tube. The heat exchange jacket is supplied with refrigerant from a refrigeration cycle machine to maintain the reaction temperature at -80°C to -20°C.
[0027] The first reactor 1 and the second reactor 2 are connected by a first mixer 41, and the second reactor 2 and the third reactor 3 are connected by a second mixer 42.
[0028] The first mixer 41 and the second mixer 42 are preferably T-type mixers.
[0029] The first liquid storage tank 61 is connected to the first reactor 1 via the first fluid transfer pump 51. The first liquid storage tank 61, the first fluid transfer pump 51 and the first reactor 1 together form the first reaction unit.
[0030] The second liquid storage tank 62 is connected to the first mixer 41 via the second fluid transfer pump 52. The second liquid storage tank 62, the second fluid transfer pump 52, the first mixer 41 and the second reactor 2 together form the second reaction unit.
[0031] The third storage tank 63 is connected to the second mixer 42 via the third fluid transfer pump 53. The third storage tank 62, the third fluid transfer pump 52, the second mixer 42 and the third reactor 3 together form the third reaction unit.
[0032] The first storage tank 61 is used to store the first reaction solution, which is an alkaline solution. The alkaline solution is selected from any one of potassium hydroxide, sodium hydroxide, sodium hydrogen, potassium hydrogen, sodium ethoxide, potassium ethoxide, sodium n-butoxide, potassium n-butoxide, sodium tert-butoxide, potassium tert-butoxide in dimethyl sulfoxide, dimethylformamide, dimethylacetamide or tetrahydrofuran solution, preferably potassium tert-butoxide in tetrahydrofuran solution.
[0033] The second storage tank 62 is used to store the second reaction solution, which is an aldehyde solution. The aldehyde solution is selected from any one of dimethyl sulfoxide, dimethylformamide, dimethylacetamide or tetrahydrofuran solution of α,β-unsaturated aldehyde, preferably tetrahydrofuran solution of crotonaldehyde.
[0034] The third storage tank 63 is used to store the third reaction solution, which is an acyl chloride solution. The acyl chloride solution is selected from any one of aliphatic or aromatic acyl chlorides, such as dimethyl sulfoxide, dimethylformamide, dimethylacetamide, or tetrahydrofuran solution, preferably aliphatic or aromatic acyl chloride tetrahydrofuran solution.
[0035] The following detailed description of the continuous production process of E-conjugated dienol ester compounds, with reference to different specific embodiments, is provided.
[0036] Example 1
[0037] The potassium tert-butoxide solution in the first storage tank 61 is fed into the first reactor 1 at a feed rate of 1.2 mol / min via the first fluid transfer pump 51 and cooled to -78°C. The residence time of the reaction solution in the first reactor 1 is 15 min.
[0038] The crotonaldehyde solution in the second storage tank 62 is fed into the first mixer 41 at a feed rate of 1 mol / min by the second fluid transfer pump 52, and mixed with the reaction solution delivered by the first reactor 1 in the first mixer 41. Then it is fed into the second reactor 2 for reaction. The reaction temperature of the second reactor 2 is controlled at -78℃, and the residence time of the reaction solution in the second reactor 2 is 10 min.
[0039] The benzoyl chloride solution in the third storage tank 63 is fed into the second mixer 42 at a feed rate of 1.2 mol / min by the third fluid transfer pump 53, and mixed with the reaction solution delivered by the second reactor 2 in the second mixer 42. Then it is fed into the third reactor 3 for reaction. The reaction temperature of the third reactor 3 is controlled at -78℃, and the residence time of the reaction solution in the third reactor 3 is 10 min.
[0040] After the reaction was completed, the products were separated and the yields were calculated. The conversion rate of crotonaldehyde was 100%, and the yield of E-conjugated dienol esters was 95%.
[0041] The reaction equations involved are as follows: .
[0042] Product confirmation: The 1H NMR spectrum of the prepared E-conjugated dienol ester compounds is shown below. Figure 2 As shown.
[0043] Example 2
[0044] The process conditions were the same as in Example 1, except that the residence time of the first reactor, the second reactor, and the third reactor was adjusted, and their effects on the yield of E-conjugated dienol esters were statistically analyzed, as shown in Table 1.
[0045] Table 1 .
[0046] Analysis: As shown in Table 1, the residence time of the first, second, and third reactors has a significant impact on the reaction yield. The best results are achieved when the residence time of the first reactor is 5 min, the residence time of the second reactor is 10 min, and the residence time of the third reactor is 20 min, with the yield of E-conjugated dienol esters reaching 98%.
[0047] Example 3
[0048] The process conditions were the same as in Example 1, except that the reaction temperatures of the first, second, and third reactors were adjusted, and their effects on the yield of E-conjugated dienol esters were statistically analyzed, as shown in Table 2. Table 2 .
[0049] Analysis: As shown in Table 2, the reaction temperatures of the first, second, and third reactors have a significant impact on the reaction yield. Considering the overall economic benefits, good yield and economy can be obtained when the temperature of the first reactor is -40℃, the temperature of the second reactor is -80℃, and the temperature of the third reactor is -80℃.
[0050] Example 4 The potassium tert-butoxide solution in the first storage tank 61 is pumped into the first reactor 1 at a rate of 1.2 mol / min using the first fluid transfer pump 51 and cooled to -40°C. The residence time of the reaction solution in the first reactor 1 is 5 min.
[0051] The crotonaldehyde solution in the second storage tank 62 is fed into the first mixer 41 at a feed rate of 1 mol / min by the second fluid transfer pump 52, and mixed with the reaction solution delivered by the first reactor 1 in the first mixer 41. Then it is fed into the second reactor 2 for reaction. The reaction temperature of the second reactor 2 is controlled at -80℃, and the residence time of the reaction solution in the second reactor 2 is 10 min.
[0052] The acetyl chloride solution in the third storage tank 63 is fed into the second mixer 42 at a feed rate of 1.2 mol / min by the third fluid transfer pump 53, and mixed with the reaction solution delivered by the second reactor 2 in the second mixer 42. Then it is fed into the third reactor 3 for reaction. The reaction temperature of the third reactor 3 is controlled at -80℃, and the residence time of the reaction solution in the third reactor 3 is 20 min.
[0053] After the reaction was completed, the products were separated and the yields were calculated. The conversion rate of crotonaldehyde was 100%, and the yield of E-conjugated dienol esters was 96%.
[0054] The reaction equations involved are as follows: .
[0055] Comparative Example 1
[0056] The reaction conditions are the same as in Example 1, except that an E-conjugated dienol ester compound is produced using a reaction vessel process, the specific process of which is as follows: (1) First, add 12 mol potassium tert-butoxide and 180 mol tetrahydrofuran to the reactor, stir to form a solution and cool to -78℃; (2) Then, mix 10 mol of crotonaldehyde and 10 mol of tetrahydrofuran and slowly add the mixture into the reactor. React at -78℃ for 10 min. (3) Slowly add a mixed solution of 12 mol benzoyl chloride and 24 mol tetrahydrofuran to the reactor and react at -78℃ for 10 min; (4) After the reaction is complete, the products are separated and the yield is calculated. The conversion rate of crotonaldehyde is 70%, and the yield of E-conjugated dienoyl esters is 50%.
[0057] analyze: Comparing the continuous production process of this invention with the existing reaction vessel production process, it can be found that: 1. This invention adopts a continuous production process, avoiding the problems of long feeding time and slow feeding in existing batch production. It is simple to operate and can achieve continuous, stable and rapid production, significantly improving production efficiency.
[0058] 2. The tubular reactor of the present invention has a large heat exchange area, which can remove the heat generated by the reaction more quickly, improve the selectivity of the target product, and improve the safety of the reaction process.
[0059] 3. The premixing and tubular reactor technology of the present invention enhances the mixing between reaction liquids, saves reaction time, and improves the yield of the target product.
[0060] The contents described in this specification are merely an enumeration of the implementation forms of the inventive concept, and the scope of protection of this invention should not be regarded as limited to the specific forms described in the embodiments.
Claims
1. A continuous production process for E-conjugated dienol ester compounds, characterized in that, Includes the following steps: (1) The alkaline solution is transferred to the first reactor and cooled to the reaction temperature; (2) The alkaline solution cooled in step (1) is transported to the first mixer for mixing with the aldehyde solution, and the mixture is then transported to the second reactor for reaction; (3) The reaction solution from step (2) is mixed with the acyl chloride solution through a second mixer and then transported to a third reactor to react, thereby preparing E-conjugated dienol ester compounds.
2. The continuous production process for E-conjugated dienol ester compounds according to claim 1, characterized in that: The alkaline solution is selected from any one of potassium hydroxide, sodium hydroxide, sodium hydrogen, potassium hydrogen, sodium ethoxide, potassium ethoxide, sodium n-butoxide, potassium n-butoxide, sodium tert-butoxide, potassium tert-butoxide, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, and tetrahydrofuran solutions; the aldehyde solution is selected from any one of α,β-unsaturated aldehyde dimethyl sulfoxide, dimethylformamide, dimethylacetamide, and tetrahydrofuran solutions; the acyl chloride solution is selected from any one of aliphatic or aromatic acyl chloride dimethyl sulfoxide, dimethylformamide, dimethylacetamide, and tetrahydrofuran solutions.
3. The continuous production process for E-conjugated dienol ester compounds according to claim 1, characterized in that: The first reactor, the second reactor, and the third reactor are single tubular reactors, or multiple tubular reactors connected in series or in parallel; the first mixer and the second mixer are selected from any one of T-type mixers, Y-type mixers, and Venturi mixers.
4. The continuous production process for E-conjugated dienol ester compounds according to claim 1, characterized in that: In step (1), the cooling temperature is -80℃ to -20℃, and the residence time in the first reactor is 5-20 minutes.
5. The continuous production process for E-conjugated dienol ester compounds according to claim 4, characterized in that: In step (1), the cooling temperature is -40℃ and the residence time in the first reactor is 5 minutes.
6. The continuous production process for E-conjugated dienol ester compounds according to claim 1, characterized in that: In step (2), the reaction temperature is -80℃ to -20℃, and the residence time in the second reactor is 5-20 minutes.
7. The continuous production process for E-conjugated dienol ester compounds according to claim 6, characterized in that: In step (2), the reaction temperature is -80℃ and the residence time in the second reactor is 10 minutes.
8. The continuous production process for E-conjugated dienol ester compounds according to claim 1, characterized in that: In step (3), the reaction temperature is -80℃ to -20℃, and the residence time in the second reactor is 5-20 minutes.
9. The continuous production process for E-conjugated dienol ester compounds according to claim 6, characterized in that: In step (3), the reaction temperature is -80℃ and the residence time in the second reactor is 20 minutes.
10. A continuous production apparatus for E-conjugated dienol ester compounds, characterized in that, It includes a first reactor, a second reactor, and a third reactor, which are connected in series. The first reactor and the second reactor are connected by a first mixer, and the second reactor and the third reactor are connected by a second mixer. The first liquid storage tank is connected to the first reactor via a first fluid transfer pump. The first liquid storage tank, the first fluid transfer pump, and the first reactor together constitute the first reaction unit. The second liquid storage tank is connected to the first mixer via a second fluid transfer pump. The second liquid storage tank, the second fluid transfer pump, the first mixer, and the second reactor constitute the second reaction unit. The third storage tank is connected to the second mixer via a third fluid transfer pump. The third storage tank, the third fluid transfer pump, the second mixer, and the third reactor together form the third reaction unit. The first storage tank is used to store the first reaction solution, which is an alkaline solution selected from any one of potassium hydroxide, sodium hydroxide, sodium hydrogen, potassium hydrogen, sodium ethoxide, potassium ethoxide, sodium n-butoxide, potassium n-butoxide, sodium tert-butoxide, potassium tert-butoxide, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, or tetrahydrofuran solution. The second storage tank is used to store the second reaction solution, which is an aldehyde solution selected from any one of dimethyl sulfoxide, dimethylformamide, dimethylacetamide or tetrahydrofuran solution of α,β-unsaturated aldehydes. The third storage tank is used to store the third reaction solution, which is an acyl chloride solution selected from any one of aliphatic or aromatic acyl chlorides, such as dimethyl sulfoxide, dimethylformamide, dimethylacetamide, or tetrahydrofuran solution.