Cyclopropyl norbornane compound, preparation method and application
By preparing cyclopropylnorbornene compounds, the problem of insufficient density and calorific value of existing hydrocarbon fuels has been solved, realizing a fuel with high density and high calorific value, suitable for aviation and aerospace fuels.
Patent Information
- Application Number
- CN202511158437.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-18
- Publication Date
- 2025-12-05
AI Technical Summary
While existing hydrocarbon fuels can increase density through ring growth strategies, their mass calorific value is low, making it difficult to design fuels with both high density and high mass calorific value.
Cyclopropylnorbornene compounds are prepared by the Diels-Alder reaction and the first cyclopropanation reaction, introducing cyclopropyl and norbornene alkyl groups to improve the calorific value and density of the fuel.
It achieves high density and high-quality calorific value for fuel, and has excellent low-temperature performance, making it suitable for aviation and aerospace fuels.
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Figure CN121064004A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to a cyclopropyl norbornane compound, a preparation method and application, and belongs to the technical field of chemical industry. BACKGROUND
[0002] High-energy-density hydrocarbon fuels are crucial to the development of the aviation industry, and in the development of hydrocarbon fuels, it is found that the density of hydrocarbons with a polycyclic structure is significantly higher than that of hydrocarbons with a monocyclic structure and a chain structure, therefore, a ring growth strategy becomes a key means to increase the density of fuels.
[0003] However, although the ring growth strategy can improve the fuel density, the fuel mass heat value is still low due to the reduction of hydrogen content, therefore, designing a fuel with high density and high mass heat value becomes a problem to be solved at present. SUMMARY
[0004] The application provides a cyclopropyl norbornane compound, a preparation method and application, the cyclopropyl norbornane compound contains relatively high tension energy in the cyclopropyl and the norbornane group, and can provide additional energy for fuel to increase the mass heat value.
[0005] The application provides a cyclopropyl norbornane compound, and the structural formula of the cyclopropyl norbornane compound is as follows:
[0006]
[0007] The application also provides a preparation method of the cyclopropyl norbornane compound, and the method comprises the following steps:
[0008] Spir[2,4]hept-4,6-diene and cyclopropyl acetylene are dissolved in a first solvent, and a norbornadiene derivative fuel matrix I is obtained through a Diels-Alder reaction.
[0009] The norbornadiene derivative fuel matrix I is subjected to a first cyclopropanation reaction to obtain the cyclopropyl norbornane compound.
[0010] The application also provides a fuel prepared based on the cyclopropyl norbornane compound, and the fuel comprises at least one of the following: aviation fuel and aerospace fuel.
[0011] The application has the following beneficial effects:
[0012] The cyclopropyl norbornane compound provided by the present application introduces cyclopropyl and norbornane group in the structure, which contains higher tension energy and can improve the mass heat value, such as the cyclopropyl norbornane compound containing four three-membered rings, which has higher mass heat value and specific impulse, and the norbornane group contained in the compound can be regarded as two compact five-membered rings, which further improves the density, at the same time, the branched cyclopropyl reduces the symmetry of the compound and increases the carbon chain, which ensures the low temperature performance. BRIEF DESCRIPTION OF DRAWINGS
[0013] The drawings incorporated in the specification and forming a part thereof illustrate embodiments consistent with the present application and together with the description are used to explain the principles of the application. In addition, the drawings and description are not intended to limit the scope of the inventive concept in any way.
[0014] Figure 1 The preparation method of the cyclopropyl norbornane compound of the embodiment of the present application is shown in the schematic diagram.
[0015] Figure 2 The mass spectrum of the spiro[2,4]hepta-4,6-diene of embodiment 1 of the present application is shown in the figure.
[0016] Figure 3 The mass spectrum of the norbornadiene derivative fuel matrix I of embodiment 1 of the present application is shown in the figure.
[0017] Figure 4 The mass spectrum of the monocyclopropane product II of embodiment 1 of the present application is shown in the figure.
[0018] Figure 5 The mass spectrum of the cyclopropyl norbornane product III of embodiment 1 of the present application is shown in the figure. DETAILED DESCRIPTION
[0019] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application. In the case of no conflict, the following embodiments and the features in the embodiments can be combined with each other.
[0020] In order to solve the technical problems in the background, the present application provides a cyclopropyl norbornane compound, the structural formula of which is as follows:
[0021]
[0022] The present application also provides a preparation method of a cyclopropyl norbornane compound, as shown in the following formula (I) : Figure 1 The method comprises the following steps:
[0023] 1. Dissolving spiro[2,4]hepta-4,6-diene and cyclopropyl acetylene in a first solvent to obtain a norbornadiene derivative fuel precursor I through a Diels-Alder reaction (D-A reaction).
[0024] The preparation method of the spiro[2,4]hepta-4,6-diene comprises the following steps: mixing cyclopentadiene, a first alkali solution and a phase transfer catalyst (PTC) to obtain a first mixed solution; adding 1,2-dichloroethane to the first mixed solution to obtain spiro[2,4]hepta-4,6-diene through a second cyclopropanation reaction.
[0025] For example, spiro[2,4]hepta-4,6-diene is obtained by spirocyclopropanation of cyclopentadiene under the catalysis of a phase transfer catalyst.
[0026] The molar ratio of the cyclopentadiene, the phase transfer catalyst and the 1,2-dichloroethane is (0.076-0.15) : (0.0076-0.75) : (0.081-0.12), preferably (0.08-0.14) : (0.018-0.6) : (0.09-0.11), more preferably 0.09:0.1:0.09, and / or 0.11:0.3:0.1, and / or 0.12:0.5:0.11; the amount of the first alkali solution is 40-100 mL, preferably 50-90 mL, more preferably 60, 70 or 80 mL.
[0027] It should be noted that the amount (molar amount) of the phase transfer catalyst is 0.1-5 mol% of the amount (molar amount) of the cyclopentadiene. When the amount of the phase transfer catalyst is less than 0.1 mol%, the phase transfer efficiency is relatively low, resulting in a relatively low yield of the reaction product. When the amount of the phase transfer catalyst is more than 5 mol%, the phase transfer catalyst has no obvious promoting effect on the reaction.
[0028] The condition parameters of the second cyclopropanation reaction include: the reaction temperature is 5-35℃, preferably 10-30℃, more preferably 15, 20 or 25℃; the reaction time is 3-20 hours, preferably 5-16 hours, more preferably 8, 10, 12 or 14 hours; and the reaction pressure is normal pressure.
[0029] The first alkali solution comprises 30-50 wt% sodium hydroxide solution and / or potassium hydroxide solution; and the phase transfer catalyst comprises at least one of quaternary phosphonium salt, quaternary ammonium salt, quaternary ammonium base, crown ether and open-chain polyether.
[0030] The molar ratio of the cyclopropylacetylene and the spiro[2,4]hepta-4,6-diene is 1:(1-6), preferably 1:(1-5), more preferably 1:(2-5), 1:(3-5), 1:(4-5); the amount of the first solvent is 10-30 mL, preferably 15-25 mL, more preferably 18, 20 and 23 mL.
[0031] The condition parameters of the Diels-Alder reaction include: the reaction temperature is 180-240 DEG C, preferably 200-230 DEG C, more preferably 210, 220 DEG C; the reaction time is 10-60 hours, preferably 20-50 hours, more preferably 30, 40 hours; the reaction pressure is high pressure 2-4 Mpa, preferably in a 3 Mpa reaction kettle and the reaction atmosphere is inert gas, such as nitrogen atmosphere, etc.
[0032] The first solvent includes at least one of cyclohexane, 1,2-dichloroethane, dichloromethane, dimethylbenzene, tetrahydrofuran and ethylene glycol dimethyl ether.
[0033] 2, norbornadiene derivative fuel matrix I is obtained by the first cyclopropanation reaction to obtain a cyclopropyl norbornane compound.
[0034] The step specifically includes: mixing the second solvent, the first catalyst, the second lye and the norbornadiene derivative fuel matrix I to obtain a second mixed solution; adding diazomethane precursor to the second mixed solution to obtain a cyclopropyl norbornane compound by the first cyclopropanation reaction. The reaction principle is specifically that diazomethane precursor reacts with the second lye to produce diazomethane, which undergoes the first cyclopropanation reaction, and then the single cyclopropanation product II is obtained, and then the final cyclopropyl norbornane product III, i.e. the cyclopropyl norbornane compound, is obtained.
[0035] The molar ratio of the first catalyst, the second lye, the norbornadiene derivative fuel matrix I and the diazomethane precursor is (1-20):(1-4):100:(100-1000), preferably (2-18):(1-3):100:(100-900), more preferably (3-15):(2-3):100:(100-800), (4-10):2:100:(100-700), 5:3:100:600; the amount of the second solvent is 10-20 mL, preferably 12-17 mL, more preferably 14, 15, 16 mL.
[0036] The condition parameter of the first cyclopropanation reaction includes: the reaction temperature is -10-40 DEG C, preferably -5-35 DEG C, more preferably 0, 5, 10, 15, 20, 25 and 30 DEG C; and the reaction time is 10-60 min, preferably 20-50 min, more preferably 30, 40 min.
[0037] The second solvent includes at least one of dichloromethane, 1,2-dichloroethane, tetrahydrofuran and ethylene glycol dimethyl ether; the catalyst includes at least one of tetraphenylporphyrin iron (FeTPPCl), copper acetylacetonate (Cu(acac)2), palladium acetylacetonate (Pd(acac)2), palladium acetate (Pd(OAc)2), copper chloride (CuCl), nickel acetylacetonate (Ni(acac)2) and bis(cyanophenyl) dichloropalladium ((PhCN)2PdCl2); the second alkali liquor includes at least one of 30-50 wt% sodium hydroxide solution, 30-50 wt% potassium hydroxide solution and 30-50 wt% barium hydroxide solution; and the diazomethane precursor includes at least one of nitrosourea compounds and nitrosop-toluenesulfonamide compounds, and the nitrosourea compound is preferably at least one of N-methyl-N-nitrosourea, N-methyl-N-nitrosop-toluenesulfonamide and N-methyl-N-nitroso-N'-nitroguanidine.
[0038] In order to better understand the above reaction, the following reaction equation is given:
[0039] The structure of the spiro[2.4]hepta-4,6-diene is The structure of the norbornadiene derivative fuel matrix I is The structure of the monocyclopropanated product II is The final cyclopropyl norbornane product III is The reaction formula is:
[0040]
[0041] The above preparation method is simple, convenient, easy to implement, low in cost and suitable for large-scale production, for example, the cyclopentadiene raw material is widely available and low in price.
[0042] The application also provides a fuel prepared based on the cyclopropyl norbornane compound, and the fuel includes at least one of aviation fuel and aerospace fuel.
[0043] The parameters of the fuel include: the density is higher than 1.01 g / mL, the mass heat value is higher than 43.6 MJ / kg, the freezing point is less than -65 DEG C and the theoretical specific impulse is higher than 333 s.
[0044] Note that the fuel includes not only the cyclopropyl norbornane compound described above but also materials that a conventional fuel should have, and thus a detailed description thereof will not be given herein.
[0045] In order to better explain the present application, examples and comparative examples are also provided below.
[0046] Example 1
[0047] A method for preparing a cyclopropyl norbornane compound is as follows:
[0048] 1. 132 g of cyclopentadiene was added to a 1 L reactor containing 5.28 g of dodecyltrimethylammonium chloride and 530 mL of a 50 wt% sodium hydroxide solution at room temperature, and 197.8 g of 1,2-dichloroethane was slowly added dropwise under mechanical stirring. After 12 hours of reaction, the reaction was quenched by adding an appropriate amount of water. The organic phase was obtained by liquid separation, washed with water, dried, and subjected to reduced-pressure distillation to obtain spiro[2,4]hepta-4,6-diene, the mass spectrum of which is shown in Figure 2 .
[0049] (2) 20 mL of cyclohexane, 1 mL of spiro[2,4]hepta-4,6-diene, and cyclopropyl ethane in a molar ratio of 1 to spiro[2,4]hepta-4,6-diene were added to a 50 mL high-pressure reaction kettle, 3 MPa of nitrogen was filled, and reaction was performed at 600 rpm and 220°C for 48 hours. After the reaction was completed, the solvent was removed by rotary evaporation, and the crude product was finally purified by reduced-pressure distillation to obtain norbornadiene derivative fuel precursor I, the mass spectrum of which is shown in Figure 3 .
[0050] (3) A three-necked jacketed flask circulating water at 10°C was added with 3.36 g of a 50 wt% potassium hydroxide solution, 95 mg of norbornadiene derivative fuel precursor I dissolved in 15 mL of dichloromethane, and 5 mol% of acetylacetone palladium (first catalyst) dissolved in 5 mL of dichloromethane under stirring. 8 mol% of N-methyl-N-nitroso urea was slowly added, and sampling was performed after 10 min of stirring, followed by further addition. The reaction was quenched by dilute nitric acid, the organic phase was extracted with dichloromethane, washed, dried, rotary evaporated, and subjected to reduced-pressure distillation to obtain final cyclopropyl norbornane product III.
[0051] The composition of the organic phase was analyzed by gas chromatography, and the selectivity of the final cyclopropyl norbornane product III was 98%, and the conversion rate of norbornadiene derivative fuel precursor I was close to 100%. The mass spectra of monocyclopropane product II and final cyclopropyl norbornane product III are shown in Figure 4 and Figure 5 .
[0052] Examples 2 to 19
[0053] The preparation method of the cyclopropane-substituted norbornane compounds of Examples 2-19 is similar to that of Example 1, except that the type of the first catalyst, the amount of the first catalyst (the amount of the first catalyst refers to the ratio of the molar amount of the first catalyst to the molar amount of the norbornadiene derivative fuel precursor I), the reaction temperature, the amount of the diazomethane precursor (the amount of the diazomethane precursor refers to the ratio of the molar amount of the diazomethane precursor to the molar amount of the norbornadiene derivative fuel precursor I), and the like used in the cyclopropanation of the norbornadiene derivative fuel precursor I in step (3) are different. See Table 1 below for details. The conversion of the norbornadiene derivative fuel precursor I and the selectivity of the final cyclopropane-substituted norbornane product III of Examples 2-19 are also shown in Table 1.
[0054] Table 1 Reaction conditions and results data table of Examples 2-19
[0055]
[0056]
[0057] Comparative Example 1
[0058] A preparation method of a cyclopropane-substituted norbornane compound is as follows:
[0059] 1. Under N2, 20 °C, 9.8 g of KOH (aq, 50 wt%, 15 eq), 18 mL of dichloromethane, 800 μL of fuel precursor 3-carene (1 eq), and 124 mg of Pd / C catalyst (Pd component accounts for 1% of the molar amount of 3-carene) were added into a 50 mL three-necked round-bottom flask, respectively.
[0060] 2. 1.8 g of N-methyl-N-nitroso urea (3 eq) was weighed and added into the flask at a speed of 0.01 g / s in two times with an interval of 0.5 h. After the reaction was completed, 5 mL of concentrated hydrochloric acid was used to quench the reaction. The reaction system was separated to obtain an aqueous phase and an organic phase. The aqueous phase was centrifuged, and then washed with 10 mL of deionized water and 10 mL of ethanol, and vacuum dried to recover the Pd / C catalyst; the organic phase was subjected to rotary evaporation at 45 °C and 25 kPa to remove the solvent to obtain a yellow oily product, the structure of which is shown in Table 2.
[0061] Comparative Examples 2-4
[0062] The preparation method of the cyclopropane-substituted norbornane compounds of Comparative Examples 2-4 is basically similar to that of Comparative Example 1, except that the cyclic olefin derivative fuel precursor in the step is terpinolene, 2-isopropylmethylene-cyclopentadiene, and 5-isopropenyl-2-norbornene, respectively. The structures of the cyclopropane-substituted norbornane compounds of Comparative Examples 2-4 are shown in Table 2.
[0063] The cyclopropane cycloalkane compounds prepared by Example 1 and Comparative Examples 1-4 were used to prepare corresponding fuels, and the performance of the fuels was tested to obtain corresponding test data, as shown in Table 2.
[0064] Table 2 Test data table of Example 1 and Comparative Examples 1-4
[0065]
[0066] According to the data in Table 2, it can be seen that the aerospace fuel obtained by using the cyclopropyl norbornane compound of Example 1 not only greatly improves the density, but also improves the mass heat value.
[0067] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.
Claims
1. A cyclopropylnorbornene compound, characterized in that, A structure of the cyclopropyl norbornane compound is as follows:
2. A process for the preparation of a cyclopropyl norbornane compound, characterized by, The method comprises the following steps: Spir[2,4]hept-4,6-diene and cyclopropyl acetylene are dissolved in a first solvent to obtain a norbornadiene derivative fuel matrix I through a Diels-Alder reaction; The norbornadiene derivative fuel matrix I is subjected to a first cyclopropanation reaction to obtain a cyclopropyl norbornane compound.
3. The method of claim 2, wherein, Before the step of dissolving spir[2,4]hept-4,6-diene and cyclopropyl acetylene in the first solvent, the method further comprises the following step of preparing the spir[2,4]hept-4,6-diene: Cyclopentadiene, a first alkali solution and a phase transfer catalyst are mixed to obtain a first mixed solution; 1,2-Dichloroethane is added to the first mixed solution to obtain spir[2,4]hept-4,6-diene through a second cyclopropanation reaction.
4. The method of claim 3, wherein, The norbornadiene derivative fuel matrix I is subjected to a first cyclopropanation reaction to obtain a cyclopropyl norbornane compound, and the method comprises the following steps: A second solvent, a first catalyst, a second alkali solution and the norbornadiene derivative fuel matrix I are mixed to obtain a second mixed solution; Diazomethane precursor is added to the second mixed solution to obtain a cyclopropyl norbornane compound through a first cyclopropanation reaction.
5. The method of claim 4, wherein, The molar ratio of the cyclopentadiene, the phase transfer catalyst, the 1,2-dichloroethane is (0.076-0.15):(0.0076-0.75):(0.081-0.12); And / or, the amount of the first alkali solution is 40-100 mL; the molar ratio of the cyclopropyl acetylene, the spir[2,4]hept-4,6-diene is 1:(1-6); And / or, the amount of the first solvent is 10-30 mL; the molar ratio of the first catalyst, the second alkali solution, the norbornadiene derivative fuel matrix I, the diazomethane precursor is (1-20):(1-4):100:(100-1000); And / or, the amount of the second solvent is 10-20 mL.
6. The method of claim 4, wherein, The condition parameters of the second cyclopropanation reaction include that the reaction temperature is 5-35℃ and the reaction time is 3-20 hours; And / or, the condition parameters of the Diels-Alder reaction include that the reaction temperature is 180-240℃ and the reaction time is 10-60 hours; And / or, the condition parameters of the first cyclopropanation reaction include that the reaction temperature is -10-40℃ and the reaction time is 10-60 min.
7. The method of claim 4, wherein, The first alkali solution comprises at least one of the following: a 30-50wt% sodium hydroxide solution, a 30-50wt% potassium hydroxide solution; And / or, the phase transfer catalyst comprises at least one of the following: a quaternary phosphonium salt, a quaternary ammonium salt, a quaternary ammonium base, a crown ether and a chain polyether; And / or, the first solvent comprises at least one of the following: cyclohexane, 1,2-dichloroethane, dichloromethane, dimethylbenzene, tetrahydrofuran and ethylene glycol dimethyl ether; And / or, the second solvent comprises at least one of the following: dichloromethane, 1,2-dichloroethane, tetrahydrofuran and ethylene glycol dimethyl ether; And / or, the first catalyst comprises at least one of: tetraphenylporphyrin iron, copper acetylacetonate, palladium acetylacetonate, palladium acetate, copper chloride and nickel acetylacetonate and bis(cyanophenyl) dichloropalladium; And / or, the second alkali solution comprises at least one of: 30-50wt% sodium hydroxide solution, 30-50wt% potassium hydroxide solution and 30-50wt% barium hydroxide solution; And / or, the diazomethane precursor comprises at least one of: nitrosoureas and nitrosoparasulfonamides.
8. The method of claim 7, wherein, The nitrosoureas comprise at least one of: N-methyl-N-nitrosourea, N-methyl-N-nitroso-p-toluenesulfonamide and N-methyl-N-nitroso-N'-nitroguanidine.
9. A fuel prepared based on the cyclopropyl norbornane compound according to claim 1, characterized by The fuel comprises at least one of: aviation fuel and space fuel.
10. The fuel of claim 9, wherein, The parameters of the fuel comprise: density higher than 1.01g / mL, mass heat value higher than 43.6MJ / kg, freezing point less than -65℃, theoretical specific impulse higher than 333s.