Synthesis method of dicyclanil intermediate
By using cyanoacetamide, triphenylphosphine and toluene in the desinil intermediate synthesis process, the temperature and stirring time are controlled, and the purity and yield of the intermediate are successfully improved, and the high temperature in the existing process is solved and the problem of many by-products has achieved safer and more economical industrial production.
Patent Information
- Application Number
- CN202411769145.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-04
- Publication Date
- 2025-02-14
AI Technical Summary
The existing synthesis process of desinier intermediates has high temperature and alkaline catalysts, resulting in many by-products, low product yield and purity, and is not suitable for industrial production.
Cyanoacetamide, triphenylphosphine and toluene are used as reaction medium, and the temperature is controlled between 25±5°C and 50°C. The reaction is stirred for 6 to 8 hours, and then the white solid is precipitated by suction filtration and drainage. Wash and dry to obtain a high purity intermediate.
This process reduces the reaction temperature, improves the purity and yield of the product, simplifies the operation steps, enhances the safety and economy of the process, and is suitable for industrial production.
Smart Images
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Abstract
Description
Technical Field
[0001] The present application relates to the technical field of organic synthesis, and in particular to a method for synthesizing a dicyandiamide intermediate. Background Art
[0002] Dicynil is a new type of insect growth regulator that works by interfering with the formation of insect cuticles. It emphasizes the control and regulation of pest populations and can selectively and effectively prevent and control pests. It has a high killing effect on dipteran insects and fleas, and can prevent the larvae of various flies, mosquitoes and fleas from developing into pupae and adults.
[0003] In the prior art, two synthetic routes of dicyclopentyl are as follows:
[0004]
[0005] Among them, the intermediate The synthesis of dicyandiamide is reported in the current process of preparing the intermediate 1-amino-1-cyanoamino-2,2-dicyanoethylene sodium salt by dissolving malononitrile and sodium dicyanamide in DMF under high temperature alkaline catalyst. Due to the high temperature (155-168°C) and the presence of alkaline catalyst, the reaction has many by-products, the product yield and purity are relatively low, and it is not conducive to industrial production. Therefore, it is urgent to develop a new synthesis route with low reaction temperature, high product purity and yield, and convenient industrial production. Summary of the invention
[0006] Purpose of the invention: In view of the deficiencies in the prior art, the present application provides a new method for synthesizing a dicyclopentane intermediate.
[0007] Technical solution: The present invention provides a method for synthesizing a dicyandiamide intermediate, and the reaction route is as follows:
[0008]
[0009] The synthesis method of the dicyandiamide intermediate of the present invention specifically comprises the following steps: adding cyanoacetamide, triphenylphosphine and toluene into a reaction container, controlling the temperature at 25±5°C and stirring for 30-35 minutes, adding sodium dicyandiamide, controlling the temperature at 20-50°C, stirring and reacting for 6-8 hours, cooling to 5-10°C to precipitate a large amount of white solid, filtering after the reaction is completed, rinsing the filter cake with toluene and then with methanol, and drying to obtain a white solid.
[0010] In the above steps, the molar ratio of cyanoacetamide to sodium dicyandiamide is 2 to 3:1, preferably 2.5:1;
[0011] In the above steps, the weight ratio of cyanoacetamide to triphenylphosphine is: 1:0.005-0.02, preferably 1:0.01;
[0012] In the above steps, the weight ratio of cyanoacetamide to toluene is 1:5-10, preferably 1:7;
[0013] In the above steps, the reaction temperature is: 20-50°C, preferably 30-35°C; the cooling temperature is: 0-30°C, preferably 5-10°C;
[0014] In the above steps, the reaction time of step 1) is 4 to 8 hours, preferably 6 hours.
[0015] Beneficial effects: This process has simple steps and operation steps, and the reaction temperature is lower than that of the original process, the process safety is improved, and the production cost is reduced. The product of this process can obtain a higher purity product without a separate refining method, which reduces the loss and cost caused by refining and is more conducive to industrial production. DETAILED DESCRIPTION
[0016] The technical solution of the present application is described in detail below through embodiments, but the protection scope of the present application is not limited to the embodiments.
[0017] Embodiment 1:
[0018] 735g of toluene was added to a 1000ml reaction bottle, stirring was started, 105g (1.25mol) of cyanoacetamide and 1g of triphenylphosphine were added, the temperature was controlled at 25-30℃ and stirred for 30 minutes; then 44.5g (0.5mol) of sodium dicyanamide was added, the temperature was controlled at 30-35℃ and reacted for 6 hours, and a large amount of white solid precipitated. Filtered by suction, the filter cake was rinsed with 100ml of toluene and 100ml of methanol respectively; the filter cake was dried at 50-60℃ for 8 hours, and the white solid was 73.8, the yield was 95.2%, and the purity was 99.5%.
[0019] Embodiment 2:
[0020] 735g of toluene was added to a 1000ml reaction bottle, stirring was started, 105g (1.25mol) of cyanoacetamide and 1g of triphenylphosphine were added, the temperature was controlled at 25-30℃ and stirred for 30 minutes; then 44.5g (0.5mol) of sodium dicyanamide was added, the temperature was controlled at 40-45℃ and reacted for 5 hours, a large amount of white solid precipitated. Suction filtration was performed, and the filter cake was rinsed with 100ml of toluene and 100ml of methanol respectively; the filter cake was dried at 50-60℃ for 8 hours, and the white solid was 72.8, the yield was 93.9%, and the purity was 99.4%.
[0021] Embodiment 3:
[0022] 735g of toluene was added to a 1000ml reaction bottle, stirring was started, 92.4g (1.1mol) of cyanoacetamide and 1g of triphenylphosphine were added, the temperature was controlled at 25-30℃ and stirred for 30 minutes; 44.5g (0.5mol) of sodium dicyanamide was added, the temperature was controlled at 30-35℃ and reacted for 6 hours, and a large amount of white solid precipitated. Filtered by suction, the filter cake was rinsed with 100ml of toluene and 100ml of methanol respectively; the filter cake was dried at 50-60℃ for 8 hours, and the white solid was 71.9, the yield was 92.8%, and the purity was 99.2%.
[0023] Comparative Example:
[0024] 6.6 g (0.1 mol) of malononitrile, 8.9 g (0.1 mol) of sodium dicyanamide and 40 mL of dimethylformamide were added to a 250 mL flask. The stirred mixture was heated to reflux (168 ° C) for 15 minutes; then, it was cooled to about room temperature. Then 150 mL of 2-butanol was added and the stirred mixture was cooled in an ice bath. The solid was filtered, washed with 2-butanol, and then dried in a vacuum oven overnight. Thus, 11.48 g of 1-amino-1-cyanoamino-2,2-dicyanoethylene sodium salt was obtained with a purity of 81.2% and a yield of 59.7%.
[0025] The above description is only a preferred embodiment of the present application and is not intended to limit the present application.
Claims
1. A method for synthesizing a dicyandiamide intermediate, characterized in that: The reaction synthesis route is as follows:
2. The method for synthesizing the dicyandiamide intermediate according to claim 1, characterized in that: The method comprises the following steps: adding cyanoacetamide, triphenylphosphine and toluene into a reaction container, controlling the temperature at 25±5°C and stirring for 30-35 minutes, adding sodium dicyandiamide, controlling the temperature at 20-50°C, stirring for reaction for 6-8 hours, cooling to 5-10°C to precipitate a large amount of white solid, filtering after the reaction is completed, rinsing the filter cake with toluene and then with methanol, and drying to obtain a white solid.
3. The method for synthesizing the dicyandiamide intermediate according to claim 1, characterized in that: In the above steps, the molar ratio of cyanoacetamide to sodium dicyandiamide is 2-3:
1.
4. The method for synthesizing the dicyandiamide intermediate according to claim 3, characterized in that: The molar ratio of cyanoacetamide to sodium dicyandiamide is 2.5:
1.
5. The method for synthesizing the dicyandiamide intermediate according to claim 1, characterized in that: In the above steps, the weight ratio of cyanoacetamide to triphenylphosphine is 1:0.005-0.
02.
6. The method for synthesizing the dicyandiamide intermediate according to claim 5, characterized in that: The weight ratio of cyanoacetamide to triphenylphosphine is 1:0.
01.
7. The method for synthesizing the dicyandiamide intermediate according to claim 1, characterized in that: In the above steps, the weight ratio of cyanoacetamide to toluene is 1:5-10.
8. The method for synthesizing the dicyandiamide intermediate according to claim 7, characterized in that: The weight ratio of cyanoacetamide to toluene is 1:
7.
9. The method for synthesizing the dicyandiamide intermediate according to claim 1, characterized in that: In the above steps, the reaction temperature is 20-50°C.
10. The method for synthesizing the dicyandiamide intermediate according to claim 1, characterized in that: In the above steps, the reaction time is 4 to 8 hours.