Method for preparing 2, 5-tetrahydrofuran dimethylamine from cyclic dinitrile
By reacting Raini cobalt and Raini nickel catalyst with cyclic dinitrile under a hydrogen atmosphere and adding alkali additives, the problem of preparing 2,5-tetrahydrofuran dimethylamine in the prior art is solved, and efficient and low-cost industrial production is achieved.
Patent Information
- Application Number
- CN202410010017.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-02
- Publication Date
- 2025-07-04
AI Technical Summary
The prior art has failed to effectively prepare 2,5-tetrahydrofuran dimethylamine, and the preparation of petroleum-based diamines has caused serious environmental pollution, so it is necessary to find renewable resources to prepare high-value-added chemicals.
Rainie cobalt and/or Rainie nickel catalyst are used to react with cyclic dinitrile under a hydrogen atmosphere, and alkali additives are added to control the reaction conditions such as temperature, pressure and time. A non-precious metal catalyst is used to carry out a one-step reaction.
It has achieved mild reaction conditions, short time, low cost, easy to obtain and separate catalysts, high reactant conversion rate and high product yield, and suitable for industrial production.
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Figure CN120247844A_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to the fields of green chemistry and energy, and particularly to a method for preparing 2,5-tetrahydrofuran dimethylamine from cyclic dinitriles. Background Art
[0002] Diamines are important basic chemicals and can be used to synthesize polymer materials such as polyamides, polyurethanes, and polyureas, and are widely used in fields such as textiles, electronics, automobiles, and aerospace. The production of diamines mostly uses non-renewable fossil resources as raw materials. The preparation routes of petroleum-based diamines are relatively mature. Industrially, adiponitrile is reduced to prepare hexamethylenediamine, and isophthalonitrile is used to prepare isophthalic dimethylamine. With the development of the world economy, the overexploitation and utilization of fossil resources have gradually caused increasingly serious environmental problems. Therefore, using new renewable resources such as biomass to prepare high-value-added chemicals, such as bio-based diamines, is crucial for alleviating the shortage of fossil resources and reducing environmental pollution.
[0003] 2,5-Tetrahydrofuran dimethylamine has a chiral structure and has two symmetric aminomethyl groups. The special nature of its molecular structure makes it play an important role in the development of chiral drugs, etc.; it can replace petroleum-based monomers such as terephthalic dimethylamine and isophthalic dimethylamine to synthesize materials such as polyamides and polyurethanes, and is not likely to cause problems such as poor stability and low degree of polymerization of such polyamide and polyurethane materials, and has great research significance and value. Le et al. acidified the Raney Ni catalyst and carried out amination reduction of 2,5-diformylfuran in a mixed atmosphere of ammonia and hydrogen, and the yield of 2,5-furan dimethylamine was 42.6%. After consulting, there is currently no relevant literature report on the preparation of 2,5-tetrahydrofuran dimethylamine. Summary of the Invention
[0004] The purpose of the present disclosure is to provide a method for preparing 2,5-tetrahydrofuran dimethylamine from cyclic dinitriles. This method has mild reaction conditions, a short reaction time, a simple and easily available catalyst, low cost and easy separation, a high conversion rate of reactants, and a high product yield.
[0005] To achieve the above purpose, the present disclosure provides a method for preparing 2,5-tetrahydrofuran dimethylamine from cyclic dinitriles, and the method includes:
[0006] Contacting a cyclic dinitrile, a catalyst, and a solvent, and carrying out a reaction in a hydrogen atmosphere; the catalyst is a Raney cobalt and / or Raney nickel catalyst;
[0007] Wherein, the cyclic dinitrile is 2,5-furandicarbonitrile or 2,5-tetrahydrofuran dinitrile; the molar ratio of the catalyst to the cyclic dinitrile is 1.5-7:1.
[0008] Optionally, the molar ratio of the catalyst to the cyclic dinitrile is 2 to 5:1; the catalyst is Raney nickel.
[0009] Optionally, the method further includes adding an alkali assistant to the reaction system, and the alkali assistant includes an inorganic base or an alkaline gas.
[0010] Optionally, the inorganic base includes one or more of sodium hydroxide, potassium hydroxide, and sodium carbonate, preferably sodium hydroxide; the alkaline gas includes ammonia.
[0011] Optionally, the molar ratio of the alkali assistant to the cyclic dinitrile is 1 to 10:1.
[0012] Optionally, the molar ratio of the alkali assistant to the cyclic dinitrile is 3 to 5:1.
[0013] Optionally, the reaction conditions include: temperature is 60 to 200 °C, reaction pressure is 0.5 to 8 MPa, and reaction time is 0.5 to 10 h.
[0014] Optionally, the reaction conditions include: temperature is 110 to 150 °C, reaction pressure is 3 to 6 MPa, and reaction time is 4 to 10 h.
[0015] Optionally, the solvent includes one or more of water, cyclohexane, n-heptane, dichloromethane, chloroform, acetonitrile, tetrahydrofuran, N,N-dimethylformamide, dioxane, toluene, ethanol, and isopropanol.
[0016] Optionally, the solvent includes one or more of tetrahydrofuran, N,N-dimethylformamide, ethanol, and isopropanol.
[0017] Through the above technical solution, using a non-noble metal catalyst with low cost, 2,5-tetrahydrofuran dimethylamine is prepared by a one-step reaction from cyclic dinitrile under specific conditions, providing an effective solution for the industrial production of 2,5-tetrahydrofuran dimethylamine. The method of the present disclosure has mild reaction conditions, short reaction time, simple and easily available catalyst, low cost and easy separation, high conversion rate of reaction substrates, and high product yield.
[0018] Other features and advantages of the present disclosure will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following specific implementation, they are used to explain the present disclosure, but do not constitute a limitation to the present disclosure. In the drawings:
[0020] Figure 1 is the GC spectrum of 2,5-tetrahydrofuran dimethylamine obtained in Example 1 of the present disclosure.
[0021] Figure 2 This is the GC-MS spectrum of 2,5-tetrahydrofuran dimethylamine obtained in Example 1 of the present disclosure.
[0022] Figure 3 This is the GC spectrum of the 2,5-tetrahydrofuran dimethylamine standard sample. Detailed Embodiments
[0023] The following further elaborates on the detailed embodiments of the present disclosure with reference to the accompanying drawings. It should be understood that the detailed embodiments described herein are only for the purpose of illustrating and explaining the present disclosure, and are not intended to limit the present disclosure.
[0024] The present disclosure provides a method for preparing 2,5-tetrahydrofuran dimethylamine from a cyclic dinitrile, the method comprising:
[0025] Bringing the cyclic dinitrile, the catalyst and the solvent into contact and reacting under a hydrogen atmosphere; the catalyst is a Raney cobalt and / or Raney nickel catalyst;
[0026] wherein the molar ratio of the catalyst to the cyclic dinitrile is 1.5 - 7:1.
[0027] The present disclosure uses a low-cost non-precious metal catalyst to directly prepare 2,5-tetrahydrofuran dimethylamine from 2,5-furandicarbonitrile in one step under specific conditions, providing an effective solution for the industrial production of 2,5-tetrahydrofuran dimethylamine. The method of the present disclosure has mild reaction conditions, short reaction time, simple and easily available catalyst, low cost and easy separation, high conversion rate of reaction substrates and high product yield.
[0028] According to an embodiment of the present disclosure, the molar ratio of the catalyst to the cyclic dinitrile is 2 - 5:1; the catalyst is Raney nickel. The above embodiment is conducive to making the catalyst have higher reaction activity and further increasing the product yield.
[0029] According to an embodiment of the present disclosure, the method further includes adding an alkali assistant to the reaction system, and the alkali assistant includes an inorganic base or an alkaline gas; in a further embodiment, the inorganic base includes one or more of sodium hydroxide, potassium hydroxide and sodium carbonate, preferably sodium hydroxide; the alkaline gas includes ammonia. The above embodiment is conducive to making the catalyst have higher reaction activity and further increasing the product yield.
[0030] According to an embodiment of the present disclosure, the molar ratio of the alkali assistant to the cyclic dinitrile is 1 - 10:1, preferably 3 - 5:1. The above embodiment is conducive to making the catalyst have higher reaction activity and further increasing the product yield.
[0031] According to an embodiment of the present disclosure, the conditions of the reaction include: the temperature is 60 to 200 °C, the reaction pressure is 0.5 to 8 MPa, and the reaction time is 0.5 to 10 h; preferably, the temperature is 110 to 150 °C, the reaction pressure is 3 to 6 MPa, and the reaction time is 4 to 10 h. The above embodiment is beneficial to making the catalyst have higher reaction activity, and further making the yield of the product higher.
[0032] According to an embodiment of the present disclosure, the solvent includes one or more of water, cyclohexane, n-heptane, dichloromethane, chloroform, acetonitrile, tetrahydrofuran, N,N-dimethylformamide, dioxane, toluene, ethanol, and isopropanol, preferably one or more of tetrahydrofuran, N,N-dimethylformamide, ethanol, and isopropanol. The above embodiment is beneficial to making the catalyst have higher reaction activity, and further making the yield of the product higher.
[0033] Both Raney Co and Raney Ni used in the present disclosure are commercial products, with low cost and high product yield, which is beneficial to the industrialization of this process flow.
[0034] The present disclosure will be further illustrated by the following examples, but the present disclosure is not limited thereby.
[0035] In the examples of the present disclosure, the 2,5-furandicarbonitrile used was purchased from aladdin company, with the product number D154959; the catalysts Raney Co and Raney Ni were purchased from Macklin company, with the product numbers R817300 and R817299 respectively; the standard sample 2,5-tetrahydrofuran dimethylamine was purchased from LGC company, with the product number B404300.
[0036] In the present disclosure, gas chromatography analysis was carried out on an instrument of model Thermo-TRACE1300; the gas chromatography-mass spectrometry (GC-MS) was carried out on an instrument of model Thermo-ISQ7000.
[0037] Unless otherwise specified, the remaining chemical reagents used in the examples are all commercially available products.
[0038] Example 1
[0039] Dissolve 0.2 g of 2,5-furandicarbonitrile in 10 mL of absolute ethanol, sonicate, pour the dissolved reaction solution into a reaction kettle, and then add 0.2 g of Raney Ni catalyst to the reaction kettle. The molar ratio of Raney Ni catalyst to 2,5-furandicarbonitrile is 2:1. First, introduce nitrogen to displace the air in the kettle five times, then introduce hydrogen to displace the nitrogen in the kettle three times, charge 4 MPa of hydrogen, stir, heat up to 120 °C, and end the reaction after 4 h. Cool to room temperature. The reaction is shown in Equation (1).
[0040] After the reaction is completed, remove the catalyst, take a sample, and analyze the product by gas chromatography. The yield of 2,5-tetrahydrofuran dimethylamine obtained by analysis is 70.36%.
[0041] Example 2
[0042] Dissolve 0.2 g of 2,5-furandicarbonitrile in 10 mL of DMF, sonicate, pour the dissolved reaction solution into a reaction kettle, and then add 0.2 g of Raney Ni catalyst to the reaction kettle. The molar ratio of Raney Ni catalyst to 2,5-furandicarbonitrile is 2:1. First, introduce nitrogen to displace the air in the kettle five times, then introduce hydrogen to displace the nitrogen in the kettle three times, charge 4 MPa of hydrogen, stir, heat up to 120 °C, and end the reaction after 4 h. Cool to room temperature. After the reaction is completed, remove the catalyst, take a sample, and analyze the product by gas chromatography. The yield of 2,5-tetrahydrofuran dimethylamine obtained by analysis is 58.23%.
[0043] Example 3
[0044] Dissolve 0.2 g of 2,5-furandicarbonitrile in 10 mL of tetrahydrofuran, sonicate, pour the dissolved reaction solution into a reaction kettle, and then add 0.2 g of Raney Ni catalyst to the reaction kettle. The molar ratio of Raney Ni catalyst to 2,5-furandicarbonitrile is 2:1. First, introduce nitrogen to displace the air in the kettle five times, then introduce hydrogen to displace the nitrogen in the kettle three times, charge 4 MPa of hydrogen, stir, heat up to 120 °C, and end the reaction after 4 h. Cool to room temperature. After the reaction is completed, remove the catalyst, take a sample, and analyze the product by gas chromatography. The yield of 2,5-tetrahydrofuran dimethylamine obtained by analysis is 55.78%.
[0045] Example 4
[0046] Dissolve 0.2 g of 2,5-furandicarbonitrile in 10 mL of isopropanol, and ultrasonicate. Pour the dissolved reaction solution into a reaction kettle, and then add 0.2 g of Raney Ni catalyst to the reaction kettle. The molar ratio of Raney Ni catalyst to 2,5-furandicarbonitrile is 2:1. First, introduce nitrogen to displace the air in the kettle five times, then introduce hydrogen to displace the nitrogen in the kettle three times, charge 4 MPa of hydrogen, stir, heat up to 120 °C, and end the reaction after 4 h. Cool to room temperature. After the reaction is completed, remove the catalyst, take samples, and analyze the product by gas chromatography. The yield of 2,5-tetrahydrofurandimethylamine obtained by analysis is 60.85%.
[0047] Example 5
[0048] Dissolve 0.2 g of 2,5-furandicarbonitrile in 10 mL of dioxane, and ultrasonicate. Pour the dissolved reaction solution into a reaction kettle, and then add 0.2 g of Raney Ni catalyst to the reaction kettle. The molar ratio of Raney Ni catalyst to 2,5-furandicarbonitrile is 2:1. First, introduce nitrogen to displace the air in the kettle five times, then introduce hydrogen to displace the nitrogen in the kettle three times, charge 4 MPa of hydrogen, stir, heat up to 120 °C, and end the reaction after 4 h. Cool to room temperature. After the reaction is completed, remove the catalyst, take samples, and analyze the product by gas chromatography. The yield of 2,5-tetrahydrofurandimethylamine obtained by analysis is 34.23%.
[0049] Example 6
[0050] Dissolve 0.2 g of 2,5-furandicarbonitrile in 10 mL of acetonitrile, and ultrasonicate. Pour the dissolved reaction solution into a reaction kettle, and then add 0.2 g of Raney Ni catalyst to the reaction kettle. The molar ratio of Raney Ni catalyst to 2,5-furandicarbonitrile is 2:1. First, introduce nitrogen to displace the air in the kettle five times, then introduce hydrogen to displace the nitrogen in the kettle three times, charge 4 MPa of hydrogen, stir, heat up to 120 °C, and end the reaction after 4 h. Cool to room temperature. After the reaction is completed, remove the catalyst, take samples, and analyze the product by gas chromatography. The yield of 2,5-tetrahydrofurandimethylamine obtained by analysis is 36.65%.
[0051] Example 7
[0052] Dissolve 0.2 g of 2,5-furandicarbonitrile in 10 mL of absolute ethanol, and ultrasonicate. Pour the dissolved reaction solution into a reaction kettle, and then add 0.2 g of the alkali assistant NaOH and 0.2 g of Raney Ni catalyst to the reaction kettle. The molar ratio of NaOH to 2,5-furandicarbonitrile is 3:1, and the molar ratio of Raney Ni catalyst to 2,5-furandicarbonitrile is 2:1. First, introduce nitrogen to displace the air in the kettle five times, then introduce hydrogen to displace the nitrogen in the kettle three times, charge 4 MPa of hydrogen, stir, heat up to 60 °C, and end the reaction after 4 h. Cool to room temperature. After the reaction is completed, remove the catalyst, take a sample, and analyze the product by gas chromatography. The yield of 2,5-tetrahydrofurandimethylamine obtained by analysis is 62.42%.
[0053] Example 8
[0054] Dissolve 0.2 g of 2,5-furandicarbonitrile in 10 mL of absolute ethanol, and ultrasonicate. Pour the dissolved reaction solution into a reaction kettle, and then add 0.2 g of the alkali assistant NaOH and 0.2 g of Raney Ni catalyst to the reaction kettle. The molar ratio of NaOH to 2,5-furandicarbonitrile is 3:1, and the molar ratio of Raney Ni catalyst to 2,5-furandicarbonitrile is 2:1. First, introduce nitrogen to displace the air in the kettle five times, then introduce hydrogen to displace the nitrogen in the kettle three times, charge 4 MPa of hydrogen, stir, heat up to 120 °C, and end the reaction after 4 h. Cool to room temperature. After the reaction is completed, remove the catalyst, take a sample, and analyze the product by gas chromatography. The yield of 2,5-tetrahydrofurandimethylamine obtained by analysis is 85.64%.
[0055] Example 9
[0056] Dissolve 0.2 g of 2,5-furandicarbonitrile in 10 mL of absolute ethanol, and ultrasonicate. Pour the dissolved reaction solution into a reaction kettle, and then add 0.2 g of the alkali assistant NaOH and 0.2 g of Raney Co catalyst to the reaction kettle. The molar ratio of NaOH to 2,5-furandicarbonitrile is 3:1, and the molar ratio of Raney Co catalyst to 2,5-furandicarbonitrile is 2:1. First, introduce nitrogen to displace the air in the kettle five times, then introduce hydrogen to displace the nitrogen in the kettle three times, charge 4 MPa of hydrogen, stir, heat up to 120 °C, and end the reaction after 4 h. Cool to room temperature. After the reaction is completed, remove the catalyst, take a sample, and analyze the product by gas chromatography. The yield of 2,5-tetrahydrofurandimethylamine obtained by analysis is 81.98%.
[0057] Example 10
[0058] Dissolve 0.2 g of 2,5-furandicarbonitrile in 10 mL of absolute ethanol, and sonicate. Pour the dissolved reaction solution into a reaction kettle, and then add 0.2 g of the base assistant NaOH and 0.15 g of Raney Ni catalyst to the reaction kettle. The molar ratio of NaOH to 2,5-furandicarbonitrile is 3:1, and the molar ratio of Raney Ni catalyst to 2,5-furandicarbonitrile is 1.5:1. First, introduce nitrogen to displace the air in the kettle five times, then introduce hydrogen to displace the nitrogen in the kettle three times, charge 4 MPa of hydrogen, stir, heat up to 120 °C, and end the reaction after 4 h. Cool to room temperature. After the reaction is completed, remove the catalyst, take samples, and analyze the product by gas chromatography. The yield of 2,5-tetrahydrofurandimethylamine obtained by analysis is 73.47%.
[0059] Example 11
[0060] Dissolve 0.2 g of 2,5-furandicarbonitrile in 10 mL of absolute ethanol, and sonicate. Pour the dissolved reaction solution into a reaction kettle, and then add 0.14 g of the base assistant NaOH and 0.2 g of Raney Ni catalyst to the reaction kettle. The molar ratio of NaOH to 2,5-furandicarbonitrile is 2:1, and the molar ratio of Raney Ni catalyst to 2,5-furandicarbonitrile is 2:1. First, introduce nitrogen to displace the air in the kettle five times, then introduce hydrogen to displace the nitrogen in the kettle three times, charge 4 MPa of hydrogen, stir, heat up to 120 °C, and end the reaction after 4 h. Cool to room temperature. After the reaction is completed, remove the catalyst, take samples, and analyze the product by gas chromatography. The yield of 2,5-tetrahydrofurandimethylamine obtained by analysis is 79.49%.
[0061] Comparative Example 1
[0062] Dissolve 0.2 g of 2,5-furandicarbonitrile in 10 mL of absolute ethanol, and sonicate. Pour the dissolved reaction solution into a reaction kettle, and then add 0.2 g of the base assistant NaOH to the reaction kettle. The molar ratio of NaOH to 2,5-furandicarbonitrile is 3:1. First, introduce nitrogen to displace the air in the kettle five times, then introduce hydrogen to displace the nitrogen in the kettle three times, charge 4 MPa of hydrogen, stir, heat up to 120 °C, and end the reaction after 4 h. Cool to room temperature. After the reaction is completed, remove the catalyst, take samples, and analyze the product by gas chromatography. The conversion rate of 2,5-furandicarbonitrile obtained by analysis is 10.06%, and no 2,5-tetrahydrofurandimethylamine is formed.
[0063] List the reaction conditions of Examples 1-11 and Comparative Example 1 in Table 1. The substrate dosage is 0.2 g, the reaction pressure is 4 MPa, and the conversion rate of the reaction substrate > 99%.
[0064] Table 1
[0065]
[0066] The method of the present disclosure uses a Raney cobalt / nickel catalyst to prepare 2,5-tetrahydrofuran dimethylamine, with high conversion rate of reactants and high yield of products. By comparing Example 1 and Example 8, it can be seen that adding an alkali promoter in the reaction makes the catalyst more active and the yield of the product higher. By comparing Examples 1-4 and Examples 5-6, it can be seen that when Raney Ni catalyzes cyclic dinitriles under the preferred solvent of the present disclosure, the catalytic activity is higher and the product yield is higher. By comparing Example 8 and Example 7, it can be seen that under the preferred reaction conditions of the present disclosure, the catalyst is more active and the yield of the product is higher. By comparing Example 8 and Example 9, it can be seen that the preferred Raney Ni catalyst of the present disclosure has higher activity and higher product yield during the hydrogenation of cyclic dinitriles. By comparing Example 8 and Example 10, it can be seen that within the preferred molar ratio range of the catalyst to cyclic dinitrile of the present disclosure, the catalyst is more active and the yield of the product is higher. By comparing Example 8 and Example 11, it can be seen that within the preferred molar ratio range of the alkali promoter to cyclic dinitrile of the present disclosure, the catalyst is more active and the yield of the product is higher.
[0067] The preferred embodiments of the present disclosure have been described in detail above with reference to the accompanying drawings. However, the present disclosure is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.
[0068] In addition, it should be noted that, among the various specific technical features described in the above specific embodiments, they can be combined in any suitable manner without conflict. To avoid unnecessary repetition, the present disclosure does not separately describe various possible combination methods.
[0069] Furthermore, any combination can be made among various different embodiments of the present disclosure as long as it does not violate the idea of the present disclosure, and it should also be regarded as the content disclosed by the present disclosure.
Claims
1. A method for preparing 2,5-tetrahydrofuran dimethylamine from cyclic dinitrile, characterized in that, The method comprises: Contacting a cyclic dinitrile, a catalyst and a solvent, and carrying out a reaction under a hydrogen atmosphere; the catalyst is a Raney cobalt and / or Raney nickel catalyst; Wherein, the cyclic dinitrile is 2,5-furandicarbonitrile, or 2,5-tetrahydrofurandicarbonitrile; the molar ratio of the catalyst to the cyclic dinitrile is 1.5-7:
1.
2. The method according to claim 1, wherein The molar ratio of the catalyst to the cyclic dinitrile is 2-5:1; the catalyst is Raney nickel.
3. The method according to claim 1, wherein, The method further comprises adding an alkali assistant to the reaction system, and the alkali assistant includes an inorganic base or an alkaline gas.
4. The method according to claim 3, wherein The inorganic base includes one or more of sodium hydroxide, potassium hydroxide and sodium carbonate, preferably sodium hydroxide; the alkaline gas includes ammonia.
5. The method according to claim 3, wherein, The molar ratio of the alkali assistant to the cyclic dinitrile is 1-10:
1.
6. The method according to claim 5, wherein The molar ratio of the alkali assistant to the cyclic dinitrile is 3-5:
1.
7. The method according to claim 1, wherein The reaction conditions include: the temperature is 60-200 °C, the reaction pressure is 0.5-8 MPa, and the reaction time is 0.5-10 h.
8. The method according to claim 7, wherein, The reaction conditions include: the temperature is 110-150 °C, the reaction pressure is 3-6 MPa, and the reaction time is 4-10 h.
9. The method according to claim 1, wherein, The solvent includes one or more of water, cyclohexane, n-heptane, dichloromethane, chloroform, acetonitrile, tetrahydrofuran, N,N-dimethylformamide, dioxane, toluene, ethanol and isopropanol.
10. The method according to claim 9, wherein, The solvent includes one or more of tetrahydrofuran, N,N-dimethylformamide, ethanol and isopropanol.