A method for the continuous flow synthesis of ethoxy acrylonitrile
By designing an internal flow pipe reactor, the problems of uneven stirring and difficulty in heat control during the synthesis of ethoxyacrylonitrile were solved, achieving a rapid reaction with high yield and low cost, thus improving production efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- XINXIANG RUINUO PHARM CO LTD
- Filing Date
- 2026-04-13
- Publication Date
- 2026-06-16
AI Technical Summary
Existing methods for synthesizing ethoxyacrylonitrile suffer from problems such as uneven stirring, difficulty in heat control, low yield and high cost due to excessive acidic feedstock, and slow reaction rate.
Continuous flow synthesis is carried out using an internal flow pipe reactor. Hydrochloric acid ethanol and nitrile sodium salt are preheated through heat exchange channels and then reacted under the stirring of the internal flow pipe reactor, which is equipped with first and second feed inlets. The internal flow pipe reactor is driven by an electric motor to rotate continuously, so as to achieve rapid mixing and temperature control.
It significantly increased the yield of ethoxyacrylonitrile to over 80%, shortened the reaction time to 10-20 minutes, reduced production costs, and achieved green and environmentally friendly production.
Smart Images
Figure CN122212974A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of chemical synthesis technology, specifically relating to a method for continuous flow synthesis of ethoxyacrylonitrile. Background Technology
[0002] The production of cytosine requires the prior synthesis of the intermediate ethoxyacrylonitrile, which suffers from poor stability due to its inherent chemical properties. Current synthesis methods typically employ a batch reactor, which suffers from issues such as uneven stirring, ineffective heat control, and excessive acidic feedstock, resulting in yields typically around 61% and a slow reaction rate, requiring 2-3 hours and leading to high costs. Therefore, there is an urgent need to optimize and improve traditional production methods. Summary of the Invention
[0003] This invention provides a method for the continuous synthesis of ethoxyacrylonitrile, comprising the following steps:
[0004] First, hydrochloric acid ethanol and nitrile sodium salt are introduced into the inner flow pipe reactor, and after preheating and temperature control reaction, ethoxy acrylonitrile is finally discharged.
[0005] Furthermore, the molar ratio of the ethanol hydrochloride to the sodium nitrile salt is 1-1.5:1.
[0006] Furthermore, the internal flow pipeline reactor is provided with a first inlet and a second inlet; the hydrochloric acid ethanol is introduced through the first inlet; and the nitrile sodium salt is introduced through the second inlet.
[0007] Furthermore, the internal flow pipeline reactor is also equipped with a heat exchange channel; the hydrochloric acid ethanol and the nitrile sodium salt are both preheated and temperature-controlled through the heat exchange channel.
[0008] Furthermore, the heat exchange channel controls the preheating temperature of hydrochloric acid ethanol and nitrile sodium salt to 4-6℃; and controls the reaction temperature of hydrochloric acid ethanol and nitrile sodium salt to 5-20℃.
[0009] Furthermore, the internal flow pipeline reactor is also provided with a reaction channel, and the reaction channel is also provided with an inner winding element. The hydrochloric acid ethanol and nitrile sodium salt flow into the reaction channel after preheating and react under the stirring and mixing of the inner winding element. After the reaction is completed, it flows out through the discharge port at the tail end of the internal flow pipeline reactor.
[0010] Furthermore, one end of the inner flow pipe reactor is equipped with a motor, a coupling, and a coupler. The main body of the inner flow pipe reactor is a hollow cylindrical structure. The first and second feed inlets are respectively located on the upper and lower sides of the main body of the inner flow pipe reactor. The reaction channel is located in the center of the inner flow pipe reactor, and an inner winding component is also provided inside it. One end of the inner winding component is connected to the coupler. When the motor is working, it drives the coupler to rotate through the coupling, thereby realizing the continuous rotation of the inner winding component.
[0011] Furthermore, the inner winding is spiral in shape, which can stir and push the hydrochloric acid ethanol and nitrile sodium salt toward the discharge port; the discharge port is located at the end away from the motor.
[0012] The present invention has the following advantages over the prior art:
[0013] The present invention features a simple overall process, fully utilizes the raw materials, reduces the overall reaction time from 2-3 hours to 10-20 minutes, and increases the yield to over 80%. This invention also boasts low overall production costs, is environmentally friendly, and has significant potential for widespread application. Attached Figure Description
[0014] Figure 1 This is a diagram of the ethoxyacrylonitrile product obtained in Example 5.
[0015] Figure 2 This is the gas phase detection spectrum of the ethoxyacrylonitrile product prepared in Example 5 of this invention.
[0016] Figure 3 This is a schematic diagram of the internal flow pipeline reactor in this invention.
[0017] In the diagram above, 1 is the motor; 2 is the coupling; 3 is the coupler; 4 is the first feed inlet; 5 is the reaction channel; 6 is the heat exchange channel; 7 is the inner winding component; 8 is the discharge port; and 9 is the second feed inlet. Detailed Implementation
[0018] To further explain the present invention, the following specific embodiments are described.
[0019] Example 1
[0020] A method for continuous flow synthesis of ethoxyacrylonitrile includes the following steps: first, ethanol hydrochloric acid and sodium cyanide are introduced into an inner flow pipeline reactor, then after preheating and temperature control reaction, ethoxyacrylonitrile is finally discharged.
[0021] Specifically, the molar ratio of ethanol hydrochloride to sodium nitrile salt is controlled to be 1:1. (See attached...) Figure 3It is known that the inner flow pipeline reactor is equipped with a first inlet 4 and a second inlet 9. Hydrochloric acid and ethanol are introduced through the first inlet 4; sodium nitrile salt is introduced through the second inlet 9. Both are processed through the heat exchange channel 6 before flowing into the reaction channel 5 for reaction. At this time, the motor 1 operates, driving the coupler 3 through the coupling 2 to achieve continuous rotation of the inner winding component 7. This propels the hydrochloric acid and ethanol and sodium nitrile salt to react while moving towards the outlet 8. Finally, the reacted ethoxyacrylonitrile flows out from the outlet 8. The preheating temperature is controlled at 4℃; the reaction temperature is controlled at 5℃.
[0022] Example 2
[0023] A method for continuous flow synthesis of ethoxyacrylonitrile includes the following steps: first, ethanol hydrochloric acid and sodium cyanide are introduced into an inner flow pipeline reactor, then after preheating and temperature control reaction, ethoxyacrylonitrile is finally discharged.
[0024] Specifically, the molar ratio of hydrochloric acid ethanol to sodium nitrile salt is controlled at 1.5:1. The internal flow-through reactor has a first inlet 4 and a second inlet 9. Hydrochloric acid ethanol is introduced through the first inlet 4; sodium nitrile salt is introduced through the second inlet 9. Both are processed through heat exchange channel 6 before flowing into reaction channel 5 for reaction. At this time, motor 1 operates, driving coupler 3 via coupling 2 to achieve continuous rotation of the internal flow-through component 7. This propels the hydrochloric acid ethanol and sodium nitrile salt towards the outlet 8 while they react, and finally, the reacted ethoxyacrylonitrile flows out from outlet 8. The preheating temperature is controlled at 6℃; the reaction temperature is controlled at 20℃.
[0025] Example 3
[0026] A method for continuous flow synthesis of ethoxyacrylonitrile includes the following steps: first, ethanol hydrochloric acid and sodium cyanide are introduced into an inner flow pipeline reactor, then after preheating and temperature control reaction, ethoxyacrylonitrile is finally discharged.
[0027] Specifically, the molar ratio of hydrochloric acid ethanol to sodium nitrile salt is controlled at 1.5:1. The internal flow-through reactor has a first inlet 4 and a second inlet 9. Hydrochloric acid ethanol is introduced through the first inlet 4; sodium nitrile salt is introduced through the second inlet 9. Both are processed through heat exchange channel 6 before flowing into reaction channel 5 for reaction. During this process, motor 1 operates, driving coupler 3 via coupling 2, thus continuously rotating the internal flow-through component 7. This propels the hydrochloric acid ethanol and sodium nitrile salt towards the outlet 8 while they react, ultimately resulting in the finished ethoxyacrylonitrile flowing out from outlet 8. The preheating temperature is controlled at 5℃; the reaction temperature is controlled at 15℃.
[0028] Example 4
[0029] A method for continuous flow synthesis of ethoxyacrylonitrile includes the following steps: first, ethanol hydrochloric acid and sodium cyanide are introduced into an inner flow pipeline reactor, then after preheating and temperature control reaction, ethoxyacrylonitrile is finally discharged.
[0030] Specifically, the molar ratio of hydrochloric acid ethanol to sodium nitrile salt is controlled to be 1-1.2:1. The internal flow-through reactor has a first inlet 4 and a second inlet 9. Hydrochloric acid ethanol is introduced through the first inlet 4; sodium nitrile salt is introduced through the second inlet 9. Both are processed through heat exchange channel 6 before flowing into reaction channel 5 for reaction. At this time, motor 1 operates, driving coupler 3 via coupling 2 to achieve continuous rotation of the internal flow-through component 7. This propels the hydrochloric acid ethanol and sodium nitrile salt towards the outlet 8 while they react, and finally, the reacted ethoxyacrylonitrile flows out from outlet 8. The preheating temperature is controlled at 5℃; the reaction temperature is controlled at 15℃.
[0031] Example 5
[0032] A method for continuous flow synthesis of ethoxyacrylonitrile includes the following steps: first, ethanol hydrochloric acid and sodium cyanide are introduced into an inner flow pipeline reactor, then after preheating and temperature control reaction, ethoxyacrylonitrile is finally discharged.
[0033] Specifically, the molar ratio of hydrochloric acid ethanol to sodium nitrile salt is controlled at 1.1:1. The internal flow-through reactor has a first inlet 4 and a second inlet 9. Hydrochloric acid ethanol is introduced through the first inlet 4; sodium nitrile salt is introduced through the second inlet 9. Both are processed through heat exchange channel 6 before flowing into reaction channel 5 for reaction. At this time, motor 1 operates, driving coupler 3 via coupling 2 to achieve continuous rotation of the internal flow-through component 7. This propels the hydrochloric acid ethanol and sodium nitrile salt towards the outlet 8 while they react, and finally, the reacted ethoxyacrylonitrile flows out from outlet 8. The preheating temperature is controlled at 5℃; the reaction temperature is controlled at 15℃.
[0034] Example 6
[0035] A method for continuous flow synthesis of ethoxyacrylonitrile includes the following steps: first, ethanol hydrochloric acid and sodium cyanide are introduced into an inner flow pipeline reactor, then after preheating and temperature control reaction, ethoxyacrylonitrile is finally discharged.
[0036] Specifically, the molar ratio of hydrochloric acid ethanol to sodium nitrile salt is controlled at 1:1. The internal flow-through reactor has a first inlet 4 and a second inlet 9. Hydrochloric acid ethanol is introduced through the first inlet 4; sodium nitrile salt is introduced through the second inlet 9. Both are processed through heat exchange channel 6 before flowing into reaction channel 5 for reaction. At this time, motor 1 operates, driving coupler 3 via coupling 2 to achieve continuous rotation of the internal flow-through component 7. This propels the hydrochloric acid ethanol and sodium nitrile salt towards the outlet 8 while they react, and finally, the reacted ethoxyacrylonitrile flows out from outlet 8. The preheating temperature is controlled at 5℃; the reaction temperature is controlled at 15℃.
[0037] To compare the effects of the present invention, the product yields of the above-mentioned Examples 3-6 were statistically analyzed, as shown in Table 1 below:
[0038] Table 1
[0039] Product yield (%) Example 3 75.3 Example 4 78.6 Example 5 80.1 Example 6 73.2
[0040] In addition, the ethoxyacrylonitrile obtained in Example 5 above was subjected to gas phase analysis, and the finished product is shown in the attached figure. Figure 1 As shown in the attached diagram. Figure 2 As shown, the results indicate that the reaction yielded an ethoxyacrylonitrile product with a purity of 98.47%.
[0041] It should be noted that, in the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.
[0042] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.
Claims
1. A method for continuous flow synthesis of ethoxyacrylonitrile, characterized in that, Includes the following steps: First, hydrochloric acid ethanol and nitrile sodium salt are introduced into the inner flow pipe reactor, and after preheating and temperature control reaction, ethoxy acrylonitrile is finally discharged.
2. The method for continuous flow synthesis of ethoxyacrylonitrile according to claim 1, characterized in that, The molar ratio of the ethanol hydrochloride to the sodium nitrile salt is 1-1.5:
1.
3. The method for continuous flow synthesis of ethoxyacrylonitrile according to claim 1, characterized in that, The internal flow pipeline reactor is provided with a first inlet (4) and a second inlet (9); the hydrochloric acid ethanol is introduced through the first inlet (4); the nitrile sodium salt is introduced through the second inlet (9).
4. The method for continuous flow synthesis of ethoxyacrylonitrile according to claim 3, characterized in that, The internal flow pipeline reactor is also equipped with a heat exchange channel (6); the hydrochloric acid ethanol and the nitrile sodium salt are both preheated and temperature controlled through the heat exchange channel (6).
5. The method for continuous flow synthesis of ethoxyacrylonitrile according to claim 4, characterized in that, The heat exchange channel (6) controls the temperature for preheating hydrochloric acid ethanol and nitrile sodium salt to 4-6℃; and controls the temperature for the reaction of hydrochloric acid ethanol and nitrile sodium salt to 5-20℃.
6. The method for continuous flow synthesis of ethoxyacrylonitrile according to claim 5, characterized in that, The internal flow pipeline reactor is also provided with a reaction channel (5), and the reaction channel (5) is also provided with an inner winding element (7). The hydrochloric acid ethanol and nitrile sodium salt flow into the reaction channel (5) after preheating, and react under the stirring and mixing of the inner winding element (7). After the reaction is completed, it flows out through the outlet (8) at the tail end of the internal flow pipeline reactor.
7. The method for continuous flow synthesis of ethoxyacrylonitrile according to claim 6, characterized in that, One end of the inner flow pipe reactor is equipped with a motor (1), a coupling (2) and a coupler (3). The main body of the inner flow pipe reactor is a hollow columnar structure. The first feed port (4) and the second feed port (9) are respectively located on the upper and lower sides of the main body of the inner flow pipe reactor. The reaction channel (5) is located in the center of the inner flow pipe reactor, and an inner winding component (7) is also provided inside it. One end of the inner winding component (7) is connected to the coupler (3). When the motor (1) is working, it drives the coupler (3) to rotate through the coupling (2), thereby realizing the continuous rotation of the inner winding component (7).
8. The method for continuous flow synthesis of ethoxyacrylonitrile according to claim 7, characterized in that, The inner winding (7) is spiral in shape and can stir and push hydrochloric acid ethanol and nitrile sodium salt toward the discharge port (8); the discharge port (8) is located at the end away from the motor (1).