Quaternary primary amine compound and preparation method thereof

Abstract

The invention relates to the technical field of organic synthesis, and particularly discloses a quaternary primary amine compound and a preparation method thereof. The quaternary primary amine compound is an amine organic compound which takes cyclohexyl as a center and simultaneously contains a quaternary amine group and a long alkyl chain and has a special structure, and the cyclohexyl in the structure can improve the rigidity of the quaternary primary amine compound; the quaternary amine group can improve the crosslinking density of the quaternary primary amine compound, and the long alkyl chain can improve the flexibility of the quaternary primary amine compound, so that the brittleness caused by high crosslinking density is balanced, the balance of pot life, strength and weather resistance is realized, and the quaternary primary amine compound has a great application prospect in the special fields of wind power blade glue, ship coating and the like.

Description

Technical Field

[0001] This application relates to the field of organic synthesis technology, and more specifically, to a quaternary primary amine compound and a method for its preparation. Background Technology

[0002] Amines are organic compounds formed when a hydrogen atom in ammonia is replaced by a hydrocarbon group. Primary amines are organic compounds formed when a hydrogen atom in an ammonia molecule is replaced by a hydrocarbon group, and their general structural formula is RNH2. Amine organic compounds are frequently used in modern medicine, agriculture, environmental protection, the dye industry, and the chemical industry, especially in the chemical industry where they are widely used as epoxy resin curing agents, polymer adhesives, and amine components in aspartic polyurea resins and polyamide resins.

[0003] With the rapid development of technology, the applications of amine organic compounds will become increasingly diverse, which also places higher demands on their performance. However, some existing amine organic compounds, such as polyetheramine D230, alicyclic diamine IPDA, and cashew phenolic isophorone diamine, often cannot simultaneously possess high crosslinking density and high toughness. Consequently, they fall short in balancing pot life, strength, and weather resistance, affecting their application in specialized fields such as wind turbine blade adhesives and marine coatings. Summary of the Invention

[0004] To address the aforementioned technical problems, this application provides a tetramethylamine compound and its preparation method.

[0005] Firstly, this application provides a tetramethylamine compound, which adopts the following technical solution: A tetramethylamine compound, wherein the structural formula of the tetramethylamine compound is:

[0006] By adopting the above technical solution, the tetramethylamine compound of this application is an amine organic compound with a special structure centered on cyclohexyl group and containing both tetramethylamine group and long alkyl chain. The cyclohexyl group in this structure can improve the rigidity of the tetramethylamine compound, the tetramethylamine group can improve the crosslinking density of the tetramethylamine compound, and the long alkyl chain can improve the flexibility of the tetramethylamine compound, thereby balancing the brittleness caused by high crosslinking density and achieving a balance between service life, strength and weather resistance. It has great application prospects in special fields such as wind turbine blade adhesives and marine coatings.

[0007] Secondly, this application provides a method for preparing a tetramethylamine compound, which employs the following technical solution: A method for preparing a tetramethylamine compound includes the following steps: S1. Isophorone diisocyanate and bis(2-cyanoethyl)amine were mixed and reacted at room temperature. After the reaction was completed, the reaction solution was extracted and the organic phase was collected, concentrated and dried to obtain a tetracyano intermediate. The reaction formula for this process is as follows: S2. The tetracyano intermediate obtained in step S1 is dissolved in a reaction solvent, then a catalyst is added. Under vacuum, nitrogen and hydrogen are introduced for gas replacement, respectively, followed by the addition of hydrogen. The pressure is controlled at 6-8 MPa, and the temperature is raised to 110-130℃ for 6-10 hours. After the reaction is complete, the reaction solution is filtered, concentrated, and dried to obtain the tetraamine compound. The reaction formula for this process is as follows:

[0008] By employing the above-described technical solution, this application uses isophorone diisocyanate and bis(2-cyanoethyl)amine as reactants, first undergoing an addition reaction followed by a hydrogenation reaction to prepare a tetramethylamine compound with a special structure centered on a cyclohexyl group and containing both a tetramethylamine group and a long alkyl chain. Although the synthetic route of this application involves a hydrogenation step, it offers high yields, controllable costs, and significantly improves the performance of the amine organic compound.

[0009] Preferably, in S1, the molar ratio of isophorone diisocyanate and bis(2-cyanoethyl)amine is 1:(2.2-3.0).

[0010] By adopting the above technical solution, this application optimizes the ratio between isophorone diisocyanate and bis(2-cyanoethyl)amine, making the reaction more complete, improving the conversion rate, and thus increasing the yield of the product.

[0011] Preferably, in step S1, the bis(2-cyanoethyl)amine is added dropwise over a period of 1-2 hours.

[0012] By adopting the above technical solution, this application allows bis(2-cyanoethyl)amine to be added dropwise to the reaction system within a time range of 1-2 hours, which makes the reaction proceed more slowly and fully, improves the conversion rate of the reaction, and thus increases the yield of the product.

[0013] Preferably, in step S1, the reaction time is 2-5 hours.

[0014] By adopting the above technical solution, this application optimizes the addition reaction time of isophorone diisocyanate and bis(2-cyanoethyl)amine, making the reaction more complete, improving the conversion rate, and thus increasing the yield of the product.

[0015] Preferably, in S1, isophorone diisocyanate is mixed with the reaction solvent and then mixed with bis(2-cyanoethyl)amine.

[0016] Preferably, in S1, the reaction solvent includes one of tetrahydrofuran, 1,4-dioxane, acetonitrile, N-methylpyrrolidone, and N,N-dimethylformamide.

[0017] By adopting the above technical solution, the reaction process of this application can be carried out in the absence of solvent or in the presence of a reaction solvent. If a reaction solvent is added, one of tetrahydrofuran, 1,4-dioxane, acetonitrile, N-methylpyrrolidone and N,N-dimethylformamide can be selected. The presence of the reaction solvent can promote the contact and mixing between the substances and improve the reaction efficiency.

[0018] Preferably, in step S2, the reaction solvent includes one of tetrahydrofuran, 1,4-dioxane, diethyl ether, and ethanol.

[0019] Preferably, in step S2, the amount of catalyst used is 8-12% of the mass of the quaternary cyano intermediate obtained in step S1.

[0020] Preferably, the catalyst is an amorphous aluminum-nickel alloy catalyst.

[0021] By adopting the above technical solution, this application adds a certain amount of amorphous aluminum-nickel alloy catalyst to the system to improve the reaction efficiency of the hydrogenation reaction process, thereby increasing the conversion rate of the reaction and thus increasing the yield of the product.

[0022] In summary, this application has the following beneficial technical effects: 1. The tetramethylamine compound of this application is an amine organic compound with a special structure centered on cyclohexyl group and containing both tetramethylamine group and long alkyl chain. The cyclohexyl group in this structure can improve the rigidity of the tetramethylamine compound, the tetramethylamine group can improve the crosslinking density of the tetramethylamine compound, and the long alkyl chain can improve the flexibility of the tetramethylamine compound, thereby balancing the brittleness caused by high crosslinking density and achieving a balance between service life, strength and weather resistance. It has great application prospects in special fields such as wind turbine blade adhesives and marine coatings. 2. The method for synthesizing the tetramethylamine compound of this application uses isophorone diisocyanate and bis(2-cyanoethyl)amine as reactants, and first performs an addition reaction followed by a hydrogenation reaction to obtain the tetramethylamine compound. Although this synthesis method involves a hydrogenation step, it has a high yield, controllable cost, and significantly improved performance of amine organic compounds. Detailed Implementation

[0023] All raw materials used in this application are commercially available products.

[0024] In some specific embodiments of the tetramethylamine compound, the molar ratio of isophorone diisocyanate to bis(2-cyanoethyl)amine is 1:(2.2-3.0); In some specific embodiments of the quaternary primary amine compounds, the amount of catalyst used is 8-12% of the mass of the quaternary cyano intermediate obtained in step S1. In some specific embodiments of the tetramethyl amine compounds, the reaction solvent for dissolving the tetramethyl cyano intermediate includes one of tetrahydrofuran, 1,4-dioxane, diethyl ether, and ethanol. In some specific embodiments of the quaternary primary amine compounds, the catalyst is an amorphous aluminum-nickel alloy catalyst, specifically one of the ZL-N411, ZL-N311, and ZL-N211 amorphous aluminum-nickel alloy catalysts from Liaoning Zhongli Catalyst Technology Co., Ltd. In some specific embodiments of the tetramethylamine compounds, the above raw materials and proportions are used, and the preparation method is as follows: S1. Isophorone diisocyanate is added to a reaction vessel, and bis(2-cyanoethyl)amine is added dropwise over a period of 1-2 hours. After the addition is complete, the reaction is carried out at room temperature for 2-5 hours. After the reaction is completed, the reaction solution is added to a separatory funnel, and then an organic solvent and saturated brine are added for extraction. The extraction is repeated three times, the organic phase is collected, concentrated and dried to obtain the tetramethylamine intermediate. S2. Dissolve the tetracyano intermediate obtained in step S1 in the reaction solvent, then add the catalyst, and under vacuum conditions, purge with nitrogen and hydrogen respectively for gas replacement, then add hydrogen, control the pressure at 6-8 MPa, and heat to 110-130℃ for 6-10 h. After the reaction is completed, filter the reaction solution, concentrate and dry it to obtain the tetraamine compound. In some specific embodiments of the tetramethyl primary amine compound, isophorone diisocyanate and a reaction solvent are added together to a reaction vessel and stirred until homogeneous. The reaction solvent includes one of tetrahydrofuran, 1,4-dioxane, acetonitrile, N-methylpyrrolidone and N,N-dimethylformamide. In some specific embodiments of the tetramethylamine compounds, the organic solvent includes one of ethyl acetate, dichloromethane, diethyl ether, and toluene; The tetramethylamine compounds prepared through the above-mentioned specific implementation methods all achieved yields of over 85%. According to ASTM D2074-2007 standard testing, the amine values ​​were all above 405 mg KOH / g. Furthermore, after mixing these compounds with E51 epoxy resin (epoxy equivalent of 200) at a ratio of 1:1.2 (active hydrogen to epoxy group), pre-prepared samples showed adhesion of 5.5 MPa, hardness of 85, tensile strength of 68 MPa, elongation at break of 12%, and a yellowing resistance grade of 3 after 100 hours of QUV aging. These compounds exhibited excellent adhesion and yellowing resistance, along with superior hardness and mechanical properties.

[0025] Based on the above, the applicant further uses the following examples to verify in detail the effects achieved by this application.

[0026] Example 1 A method for preparing a tetramethylamine compound includes the following steps: S1. In a three-necked flask equipped with a thermometer, a constant pressure titration funnel, a nitrogen balloon, and a stirrer, add isophorone diisocyanate (50 g, 0.2249 mol) and tetrahydrofuran (110 g) and stir until homogeneous. Then, slowly add bis(2-cyanoethyl)amine (60.86 g, 0.4948 mol) using a constant pressure titration funnel, controlling the addition time to 1 h. After the addition is complete, react at room temperature for 3 h. After the reaction is complete, add the reaction solution to a separatory funnel and extract with 150 mL of ethyl acetate and 100 mL of saturated saline solution, respectively. Repeat the extraction three times, collect the organic phase, dry it with anhydrous sodium sulfate, concentrate it to remove ethyl acetate, and obtain a tetracyano intermediate. S2. Dissolve the tetracyano intermediate obtained in step S1 in 200 mL of tetrahydrofuran, add it to a high-pressure reactor, and then add 10% by weight of the catalyst (ZL-N411 amorphous aluminum-nickel alloy catalyst). Seal the high-pressure reactor, evacuate it, and purge it with nitrogen three times and hydrogen three times. After the purging is complete, add hydrogen and maintain the pressure at 6 MPa. Then raise the temperature to 120 °C and react for 6 h. After the reaction is complete, pour off the reaction solution, filter to remove the catalyst, concentrate and dry to remove the tetrahydrofuran solvent, and obtain the tetracyanoamine compound (96.71 g, yield 88.72%).

[0027] Example 2 A method for preparing a tetramethylamine compound includes the following steps: S1. In a three-necked flask equipped with a thermometer, a constant pressure titration funnel, a nitrogen balloon, and a stirrer, add isophorone diisocyanate (50 g, 0.2249 mol) and tetrahydrofuran (120 g) and stir until homogeneous. Then, slowly add bis(2-cyanoethyl)amine (69.16 g, 0.5623 mol) using a constant pressure titration funnel, controlling the addition time to 1.5 h. After the addition is complete, react at room temperature for 4 h. After the reaction is complete, add the reaction solution to a separatory funnel and extract with 150 mL of ethyl acetate and 100 mL of saturated saline solution, respectively. Repeat the extraction three times, collect the organic phase, dry it with anhydrous sodium sulfate, concentrate it to remove ethyl acetate, and obtain a tetracyano intermediate. S2. Dissolve the tetracyano intermediate obtained in step S1 in 200 mL of tetrahydrofuran, add it to a high-pressure reactor, and then add 10% by weight of the catalyst (ZL-N311 amorphous aluminum-nickel alloy catalyst). Seal the high-pressure reactor, evacuate it, and purge it with nitrogen three times and hydrogen three times. After the purging is completed, add hydrogen and maintain the pressure at 6 MPa. Then raise the temperature to 120℃ and react for 6 h. After the reaction is completed, pour off the reaction solution, filter to remove the catalyst, concentrate and dry to remove the tetrahydrofuran solvent, and obtain the tetraamine compound (95.63 g, yield 87.73%).

[0028] Example 3 A method for preparing a tetramethylamine compound includes the following steps: S1. In a three-necked flask equipped with a thermometer, a constant pressure titration funnel, a nitrogen balloon, and a stirrer, add isophorone diisocyanate (50 g, 0.2249 mol) and tetrahydrofuran (135 g) and stir until homogeneous. Then, slowly add bis(2-cyanoethyl)amine (83.00 g, 0.6747 mol) using a constant pressure titration funnel, controlling the addition time to 2 h. After the addition is complete, react at room temperature for 4 h. After the reaction is complete, add the reaction solution to a separatory funnel and extract with 150 mL of ethyl acetate and 100 mL of saturated saline solution, respectively. Repeat the extraction three times, collect the organic phase, dry it with anhydrous sodium sulfate, concentrate it to remove ethyl acetate, and obtain a tetracyano intermediate. S2. Dissolve the tetracyano intermediate obtained in step S1 in 200 mL of tetrahydrofuran, add it to a high-pressure reactor, and then add 10% (by weight) of the catalyst (ZL-N211 amorphous aluminum-nickel alloy catalyst). Seal the high-pressure reactor, evacuate it, and purge it with nitrogen three times and hydrogen three times. After the purging is complete, add hydrogen and maintain the pressure at 6 MPa. Then raise the temperature to 120 °C and react for 6 h. After the reaction is complete, pour off the reaction solution, filter to remove the catalyst, concentrate and dry to remove the tetrahydrofuran solvent, and obtain the tetracyanoamine compound (98.86 g, yield 90.69%).

[0029] Example 4 A method for preparing a tetramethylamine compound includes the following steps: S1. In a three-necked flask equipped with a thermometer, a constant pressure titration funnel, a nitrogen balloon, and a stirrer, add isophorone diisocyanate (50 g, 0.2249 mol) and tetrahydrofuran (135 g) and stir until homogeneous. Then, slowly add bis(2-cyanoethyl)amine (83.00 g, 0.6747 mol) using a constant pressure titration funnel, controlling the addition time to 2 h. After the addition is complete, react at room temperature for 4 h. After the reaction is complete, add the reaction solution to a separatory funnel and extract with 150 mL of ethyl acetate and 100 mL of saturated saline solution, respectively. Repeat the extraction three times, collect the organic phase, dry it with anhydrous sodium sulfate, concentrate it to remove ethyl acetate, and obtain a tetracyano intermediate. S2. Dissolve the tetracyano intermediate obtained in step S1 in 200 mL of tetrahydrofuran, add it to a high-pressure reactor, and then add 10% (by mass) of the catalyst (ZL-N211 amorphous aluminum-nickel alloy catalyst). Seal the high-pressure reactor, evacuate it, and purge it with nitrogen three times and hydrogen three times. After the purging is complete, add hydrogen and maintain the pressure at 6 MPa. Then raise the temperature to 130 °C and react for 6 h. After the reaction is complete, pour off the reaction solution, filter to remove the catalyst, concentrate and dry to remove the tetrahydrofuran solvent, and obtain the tetracyanoamine compound (100.04 g, yield 91.77%).

[0030] Example 5 A method for preparing a tetramethylamine compound includes the following steps: S1. In a three-necked flask equipped with a thermometer, a constant pressure titration funnel, a nitrogen balloon, and a stirrer, add isophorone diisocyanate (50 g, 0.2249 mol) and tetrahydrofuran (135 g) and stir until homogeneous. Then, slowly add bis(2-cyanoethyl)amine (83.00 g, 0.6747 mol) using a constant pressure titration funnel, controlling the addition time to 2 h. After the addition is complete, react at room temperature for 4 h. After the reaction is complete, add the reaction solution to a separatory funnel and extract with 150 mL of ethyl acetate and 100 mL of saturated saline solution, respectively. Repeat the extraction three times, collect the organic phase, dry it with anhydrous sodium sulfate, concentrate it to remove ethyl acetate, and obtain a tetracyano intermediate. S2. Dissolve the tetracyano intermediate obtained in step S1 in 200 mL of tetrahydrofuran, add it to a high-pressure reactor, and then add 10% (by mass) of the catalyst (ZL-N211 amorphous aluminum-nickel alloy catalyst). Seal the high-pressure reactor, evacuate it, and purge it with nitrogen three times and hydrogen three times. After the purging is complete, add hydrogen and maintain the pressure at 8 MPa. Then raise the temperature to 130 °C and react for 6 h. After the reaction is complete, pour off the reaction solution, filter to remove the catalyst, concentrate and dry to remove the tetrahydrofuran solvent, and obtain the tetracyanoamine compound (101.25 g, yield 92.88%).

[0031] Example 6 A method for preparing a tetramethylamine compound includes the following steps: S1. In a three-necked flask equipped with a thermometer, a constant pressure titration funnel, a nitrogen balloon, and a stirrer, add isophorone diisocyanate (50 g, 0.2249 mol) and tetrahydrofuran (135 g) and stir until homogeneous. Then, slowly add bis(2-cyanoethyl)amine (83.00 g, 0.6747 mol) using a constant pressure titration funnel, controlling the addition time to 2 h. After the addition is complete, react at room temperature for 4 h. After the reaction is complete, add the reaction solution to a separatory funnel and extract with 150 mL of ethyl acetate and 100 mL of saturated saline solution, respectively. Repeat the extraction three times, collect the organic phase, dry it with anhydrous sodium sulfate, concentrate it to remove ethyl acetate, and obtain a tetracyano intermediate. S2. Dissolve the tetracyano intermediate obtained in step S1 in 200 mL of tetrahydrofuran, add it to a high-pressure reactor, and then add 10% by mass of the catalyst (ZL-N211 amorphous aluminum-nickel alloy catalyst). Seal the high-pressure reactor, evacuate it, and purge it with nitrogen three times and hydrogen three times. After the purging is complete, add hydrogen and maintain the pressure at 6 MPa. Then raise the temperature to 130℃ and react for 10 h. After the reaction is complete, pour off the reaction solution, filter to remove the catalyst, concentrate and dry to remove the tetrahydrofuran solvent, and obtain the tetracyanoamine compound (98.36 g, yield 90.23%).

[0032] The yields of the tetramethylamine compounds prepared in the above examples were statistically analyzed and their amine values ​​were tested. The results are shown in Table 1. The standard for testing the primary amine value of the tetramethylamine compounds is ASTM D2074-2007.

[0033] Table 1 project Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Yield (%) 88.72 87.73 90.69 91.77 92.88 90.23 Amine value (mgKOH / g) 410.34 408.74 420.47 425.48 431.63 420.34 As can be seen from Table 1, the yield of the tetramethylamine compound obtained by the synthesis method of this application is above 85%, and the amine value is above 405 mgKOH / g. The experimental results show that the tetramethylamine compound obtained by the synthesis method of this application has a high yield and amine value.

[0034] Performance testing The tetramethylamine compound obtained in Example 2, polyetheramine D230, isophorone diisocyanate IPDA, and cashew phenol modified amine curing agent were mixed with E51 epoxy resin (epoxy equivalent 200) at a ratio of active hydrogen to epoxy group of 1:1.2 to prepare samples. A portion of each sample was placed in a vacuum drying oven at room temperature to remove air bubbles, poured into a mold, and left to stand. The mold was then placed in an oven for curing. The resulting specimens were used to test hardness (Shore D) and mechanical properties (tensile strength and elongation at break). Samples were then coated onto treated tinplate (50mm×120mm×0.3mm) to form test plates. Each test plate was treated at a temperature of (23±2)℃ and a relative humidity of (50±5)% for 16 hours before adhesion and yellowing resistance tests were performed. The test results are shown in Table 2. The testing standards for hardness (Shore D) are GB / T 2411-2008; the testing standards for mechanical properties are GB / T 1040.2-2022; the testing standards for resistance to yellowing are ASTM G154 (QUV 100h), with the test grade determined visually (grade 5 being the best); and the testing standards for adhesion are GB / T 5210-2006.

[0035] Table 2 As shown in Table 2, the tetramethylamine compound (structural characteristics: tetramethylamine group + flexible aliphatic chain + cyclohexyl group + disubstituted urea group) prepared in this application has an adhesion of 5.5 MPa, a hardness (Shore D) of 85, a tensile strength of 68 MPa, an elongation at break of 12%, and a grade of 3 after 100 hours of QUV aging; while the polyetheramine D230 (structural characteristics: polyetheramine, flexible ether chain) has an adhesion of 6.9 MPa, a hardness (Shore D) of 74, a tensile strength of 42 MPa, an elongation at break of 80%, and a grade of 4 after 100 hours of QUV aging; IPDA (structural characteristics: alicyclic diamine, rigid cyclic structure) has an adhesion of 1.7 MPa and a hardness (Shore D) of 79. The tensile strength was 60 MPa, the elongation at break was 5.6%, and the grade was 4 after 100 h of QUV aging. The adhesion of the cashew phenol modified amine curing agent (structural characteristics of modified amine, flexible aliphatic chain + aromatic ring) was 2.0 MPa, the hardness (Shore D) was 81, the tensile strength was 48 MPa, the elongation at break was 14%, and the grade was 2 after 100 h of QUV aging. The experimental results show that the tetramethylamine compound prepared in this application, compared with amine epoxy curing agents such as D230, IPDA, and cashew phenol modified amine curing agent, significantly improves hardness and mechanical properties, especially tensile strength, by introducing urea bonds to connect cyclohexyl groups and aliphatic primary amines, while maintaining good adhesion and yellowing resistance.

[0036] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A tetramethylamine compound, characterized in that, The structural formula of the tetramethylamine compound is:

2. A method for preparing the tetramethylamine compound according to claim 1, characterized in that, Includes the following steps: S1. Isophorone diisocyanate and bis(2-cyanoethyl)amine were mixed and reacted at room temperature. After the reaction was completed, the reaction solution was extracted and the organic phase was collected, concentrated and dried to obtain a tetracyano intermediate. The reaction formula for this process is as follows: S2. The tetracyano intermediate obtained in step S1 is dissolved in a reaction solvent, then a catalyst is added. Under vacuum, nitrogen and hydrogen are introduced for gas replacement, respectively, followed by the addition of hydrogen. The pressure is controlled at 6-8 MPa, and the temperature is raised to 110-130℃ for 6-10 hours. After the reaction is complete, the reaction solution is filtered, concentrated, and dried to obtain the tetraamine compound. The reaction formula for this process is as follows:

3. The method for preparing a tetramethylamine compound according to claim 2, characterized in that, In S1, the molar ratio of isophorone diisocyanate and bis(2-cyanoethyl)amine is 1:(2.2-3.0).

4. The method for preparing a tetramethylamine compound according to claim 2, characterized in that, In S1, bis(2-cyanoethyl)amine is added dropwise over a period of 1-2 hours.

5. The method for preparing a tetramethylamine compound according to claim 2, characterized in that, In S1, the reaction time is 2-5 hours.

6. The method for preparing a tetramethylamine compound according to claim 2, characterized in that, In S1, isophorone diisocyanate is mixed with the reaction solvent and then mixed with bis(2-cyanoethyl)amine.

7. The method for preparing a tetramethylamine compound according to claim 6, characterized in that, In S1, the reaction solvent includes one of tetrahydrofuran, 1,4-dioxane, acetonitrile, N-methylpyrrolidone, and N,N-dimethylformamide.

8. The method for preparing a tetramethylamine compound according to claim 2, characterized in that, In S2, the reaction solvent includes one of tetrahydrofuran, 1,4-dioxane, diethyl ether, and ethanol.

9. The method for preparing a tetramethylamine compound according to claim 2, characterized in that, In step S2, the amount of catalyst used is 8-12% of the mass of the quaternary cyano intermediate obtained in step S1.

10. The method for preparing a tetramethylamine compound according to claim 9, characterized in that, The catalyst is an amorphous aluminum-nickel alloy catalyst.

Images