1, 4-fullerene C60 derivative and preparation method thereof

Abstract

The invention provides a 1, 4-fullerene C60 derivative and a preparation method thereof. The preparation method of the fullerene C60 derivative comprises the following steps: sequentially adding an organic solvent and a tetrabutyl ammonium hydroxide (TBAOH) solution into a reaction flask, introducing inert gas as shielding gas, adding an ester organic matter and fullerene C60, stirring at 25-60 DEG C, then adding iodine into the system, ending the reaction after a period of time, spin-drying the solvent through a rotary evaporator, and obtaining the fullerene C60 derivative. Carrying out acetonitrile precipitation treatment and filtering to obtain a crude product; and dissolving the crude product in toluene, and separating and purifying by high performance liquid chromatography to obtain the fullerene derivative. The preparation method of the fullerene derivative is simple to operate, mild in reaction condition, safe, easy to control, efficient and high in selectivity. # imgabs0 #

Description

Technical Field

[0001] The present invention belongs to the technical field of organic synthesis and specifically relates to a 1,4-fullerene C 60 Derivatives and methods for their preparation. Background Art

[0002] Since fullerene was first discovered in 1985, with the in-depth exploration of its structure and chemical properties by researchers, many innovative fullerene derivatives have been successfully synthesized and widely used in many fields. Fullerene derivatives are prepared by introducing various functional groups into the fullerene carbon cage structure, which constitutes the core content of fullerene chemistry research. The functionalization of fullerene not only significantly improves its solubility in common solvents, but also effectively regulates its energy level and stacking structure, thereby broadening its application prospects in many fields such as materials science, biological applications and nanotechnology.

[0003] The addition reaction of fullerene can occur between different carbon atom pairs. The most common addition modes are 1,2-addition and 1,4-addition. When the addition group is a small group or a group that is prone to cyclization, the addition will tend to be 1,2-addition. When the addition group is large, the addition mode tends to be 1,4-addition. The photoelectric properties of fullerene derivatives are significantly affected by their addition mode and functional groups. Compared with the 1,2-addition product, the 1,4-addition product exhibits more significant electron deficiency and a wider spectral absorption range. PCBM (Phenyl-C 61 -butyric acidmethyl ester) is a widely used acceptor material in the field of organic solar cells and is highly praised for its excellent electron transport performance. The ester group contained in its structure can effectively improve the solubility of PCBM in organic solvents. This feature is conducive to the formation of a uniform film in the processing link, thereby improving the performance and processability of the device. At the same time, the ester group can also improve the interfacial compatibility between PCBM and other organic materials (such as polymer donor materials). Such compatibility helps to build a more stable phase separation structure, thereby improving the stability and efficiency of the device. Therefore, in the modification of fullerene derivatives, the careful selection of functional groups has a crucial influence on improving the solubility and interfacial compatibility of the material.

[0004] Therefore, the present invention proposes a new method for preparing fullerene C with 1,4-addition mode and containing ester group, which is convenient to operate, has excellent reaction selectivity and mild reaction conditions. 60 derivatives, which is important for the future realization of 1,4-fullerene C 60 The functional synthesis of derivatives and the development of new strategies for the synthesis of fullerene derivatives are both of great value and significance. Summary of the invention

[0005] The purpose of the present invention is to provide a 1,4-fullerene C 60 Derivatives and preparation methods thereof. This 1,4-fullerene C 60 The ester and alkoxy functional groups on the carbon cage surface of the derivative adopt 1,4-addition mode, which has novel structural characteristics. Compared with 1,2-fullerene C 60 The derivative has a more significant electron-deficient property and a wider spectral absorption range. Due to the presence of ester groups in its molecular structure, the derivative has good solubility, and because of its excellent electron transport performance, it can be used as an electron transport / acceptor material for solar cells with great application potential. At the same time, this synthesis method has the advantages of strong operability, low-cost and easy-to-obtain reaction raw materials, mild reaction conditions, safety and easy control, high efficiency, and high selectivity.

[0006] A first aspect of the present invention provides a 1,4-fullerene C 60 Derivatives, the 1,4-fullerene C 60 The structural formula of the derivative is shown in Formula I, wherein R is selected from a methyl group or an ethyl group.

[0007]

[0008] The second aspect of the present invention provides a 1,4-fullerene C 60 The preparation method of the derivative comprises the following preparation steps:

[0009] Add organic solvent and tetrabutylammonium hydroxide methanol solution to the reaction flask in sequence, introduce inert gas as protective gas and add ester organic matter and stir at 25°C to 60°C for 0.5 to 1h; add C 60 The reaction solution is stirred for 0.5 to 1 hour, and then iodine is added to the system. The reaction is terminated after 0.5 to 1 hour. The reaction solution is evaporated and desolventized, precipitated with acetonitrile, and filtered to obtain the 1,4-fullerene C 60 The chemical reaction of the derivative is shown in Formula II.

[0010]

[0011] In the technical solution of the present invention, an organic solvent and a tetrabutylammonium hydroxide (TBAOH) methanol solution are sequentially added to a reaction flask. The solubility of fullerene in the organic solvent N,N-dimethylformamide is relatively low, but it can dissolve fullerene anion intermediates and enhance the stability of fullerene anions, which is conducive to the reaction. The methanol in the tetrabutylammonium hydroxide methanol solution reacts with the tetrabutylammonium hydroxide to generate alkoxy anions, which can react with C 60 An addition reaction occurs to generate C 60- -OCH3 anion intermediate, under the action of iodine, reacts with the anion formed by deprotonation of ester organic matter to generate the target 1,4-fullerene C 60 Derivatives, the reaction selectivity is high. At the same time, the inert gas is introduced to exhaust the air, which plays a protective role, protecting the fullerene anion intermediate from being oxidized and consumed by oxygen in the air, providing basic conditions for the selective generation of 1,4-addition fullerene derivatives. In summary, the preparation method is simple in experimental operation, mild in reaction conditions, safe and easy to control, fast in reaction speed and high in selectivity.

[0012] Preferably, the organic solvent is N,N-dimethylformamide.

[0013] In the technical solution of the present invention, the organic solvent is N,N-dimethylformamide, which can dissolve the fullerene anion intermediate, help the reaction proceed and stabilize the fullerene anion intermediate, thereby improving the selectivity of the reaction product.

[0014] Preferably, the tetrabutylammonium hydroxide (TBAOH) solution is a tetrabutylammonium hydroxide (TBAOH) methanol solution, and the solution concentration is 0.5 mol / L to 1.5 mol / L.

[0015] In the technical solution of the present invention, in a tetrabutylammonium hydroxide (TBAOH) methanol solution, methanol reacts with tetrabutylammonium hydroxide to generate alkoxy anions, which can react with C 60 Nucleophilic addition reaction occurs to generate C 60 - -OCH3 anion intermediate. When the concentration of tetrabutylammonium hydroxide (TBAOH) methanol solution is between 0.5 mol / L and 1.5 mol / L, it has a higher reaction activity, which is conducive to the formation of fullerene anion intermediate C 60 - The formation of -OCH3 can effectively promote the chemical modification and functionalization of fullerenes.

[0016] Preferably, the inert gas is selected from nitrogen and argon.

[0017] In the technical solution of the present invention, the inert gas is selected from one of nitrogen and argon. Both nitrogen and argon can effectively isolate the air and protect the reaction system, so that the generated fullerene anion intermediate can exist stably in the solution, which is conducive to the selective generation of the 1,4-fullerene C 60 Derivatives provide the basic conditions.

[0018] Preferably, the ester organic compound is selected from dimethyl ethyl malonate and diethyl ethyl malonate, and the fullerene C 60The molar ratio of the ester organic matter is 1:5 to 1:10.

[0019] In the technical solution of the present invention, the ester organic compound is selected from dimethyl ethyl malonate and diethyl ethyl malonate. The active α-hydrogen in dimethyl ethyl malonate or diethyl ethyl malonate is easily deprotonated to form a carbon anion, which is beneficial to the selective generation of the target 1,4-fullerene C 60 Derivatives. The fullerene C 60 The molar ratio of fullerene C to the ester organic matter is 1:5 to 1:10. Within this range, the reaction can proceed fully. 60 When the molar ratio of fullerene C to ester organic matter is lower than this range, the concentration of reactants is insufficient, resulting in a reduced reaction rate and incomplete reaction, thus affecting the reaction yield. 60 When the molar ratio to the ester organic matter is higher than this range, it leads to excessive consumption of resources and is not beneficial to improving the reaction efficiency.

[0020] Preferably, the reaction temperature is 25°C to 60°C.

[0021] In the technical solution of the present invention, the reaction temperature is 25°C to 60°C. The temperature within this range is beneficial to the target 1,4-fullerene C 60 The output of derivatives also ensures the stable progress of the reaction, which is safe and easy to control.

[0022] Preferably, the fullerene C 60 The molar ratio of tetrabutylammonium hydroxide (TBAOH) is 1:3 to 1:6.

[0023] In the technical solution of the present invention, the fullerene C 60 The molar ratio of fullerene to tetrabutylammonium hydroxide (TBAOH) is 1:3 to 1:6. Within this range, a fully efficient reaction can be carried out. When the molar ratio of fullerene to TBAOH is less than 1:3, fullerene cannot fully react to generate C 60 - -OCH3 anion intermediate; when the molar ratio of fullerene to TBAOH is higher than 1:6, excessive TBAOH consumption results in unnecessary consumption and waste of resources.

[0024] Preferably, the fullerene C 60 The molar ratio of the iodine to the iodine is 1:1 to 1:3.

[0025] In the technical solution of the present invention, the fullerene C 60 The molar ratio of the fullerene C to the iodine is 1:1 to 1:3. Within this range, the reaction can be carried out efficiently. 60When the molar ratio of fullerene C to iodine is lower than this range, the concentration of iodine is insufficient and the reaction cannot proceed fully. 60 When the molar ratio to iodine is higher than this range, side reactions may occur and the amount of by-products may increase.

[0026] Preferably, the purification method is high performance liquid chromatography separation.

[0027] Specifically, the method comprises: using a Buckyprep separation column, injecting the re-dissolved crude fullerene derivative product into a high performance liquid chromatography for separation and purification under a toluene mobile phase to obtain a pure product. The purification method can achieve a good purification effect.

[0028] The technical solution of the present invention has the following beneficial effects:

[0029] (1) 1,4-fullerene C provided by the present invention 60 The derivatives, the ester groups and alkoxy functional groups on the surface of the carbon cage adopt 1,4-addition mode, and have novel structural characteristics. The derivatives are more electron-deficient, have better solubility and wider spectral absorption, which are crucial to the performance of the electron transport layer in solar cells and are of great significance in the field of organic solar cells and perovskite solar cells.

[0030] (2) 1,4-fullerene C provided by the present invention 60 The organic solvent in the preparation method of the derivative can dissolve and stabilize the fullerene anion intermediate, which is helpful for the reaction. The experimental operation of the preparation method is simple and easy, the reaction rate is fast, the reaction conditions are mild and easy to control, the whole reaction process is safe and reliable, and the selectivity of the reaction is significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 1,4-Fullerene C 60 Schematic diagram of the molecular structure of derivative 1

[0032] Figure 2 1,4-Fullerene C 60 Derivative 1 1 H NMR spectrum

[0033] Figure 3 1,4-Fullerene C 60 UV-visible absorption spectrum of derivative 1

[0034] Figure 4 1,4-Fullerene C 60 Schematic diagram of the molecular structure of derivative 2

[0035] Figure 5 1,4-Fullerene C 60 Derivative 21 H NMR spectrum

[0036] Figure 6 1,4-Fullerene C 60 Derivative 2 13 C NMR spectrum

[0037] Figure 7 1,4-Fullerene C 60 UV-visible absorption spectrum of derivative 2 DETAILED DESCRIPTION

[0038] Below in conjunction with the accompanying drawings and Examples, the content of the present invention is described in more detail, although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and the scope of the present invention can be fully communicated to those skilled in the art. Those who do not indicate specific conditions in the embodiments are carried out according to normal conditions or the conditions recommended by the manufacturer. Those who do not indicate manufacturers for reagents or instruments used are conventional products that can be purchased commercially or synthesized by known chemical methods.

[0039] In particular, in all the following examples, the addition of N times the molar equivalent of a drug means that the amount of the drug to be added is the amount of fullerene C added in this example. 60 N times the amount of substance.

[0040] Example 1

[0041] The steps include:

[0042] To the reaction flask, 30 mL of N,N-dimethylformamide, 347 μL of 5-fold molar equivalent of tetrabutylammonium hydroxide (TBAOH) methanol solution (1 mol / L), and 128 μL of 10-fold molar equivalent of diethyl ethylmalonate were added in sequence, and inert argon gas was introduced as a protective gas. The mixture was stirred at 30 °C for 0.5 h, and then 50 mg of C was added. 60 , continue stirring for 1 hour, then add 18 mg of iodine in a molar equivalent to the system, and terminate the reaction after 1 hour. After drying on a rotary evaporator, acetonitrile precipitation treatment and sand core filter organic filter membrane filtration. The obtained solid is a crude product containing 1,4-fullerene derivative 1; the solid crude product is dissolved in toluene, and separated and purified by high performance liquid chromatography, with toluene as the mobile phase, the detection wavelength at 380 nm, and the flow rate at 4 mL / min, using a Buckyprep separation column to obtain a pure product of 1,4-fullerene derivative 1.

[0043] Example 2

[0044] The steps include:

[0045] To the reaction flask, 30 mL of N,N-dimethylformamide, 347 μL of 5-fold molar equivalent of tetrabutylammonium hydroxide (TBAOH) methanol solution (1 mol / L), and 64 μL of 5-fold molar equivalent of diethyl ethylmalonate were added in sequence, and inert argon gas was introduced as a protective gas. The mixture was stirred at 60 °C for 1 h, and then 50 mg of C was added. 60 , continue stirring for 1 hour, then add 35 mg of iodine in a 2-fold molar equivalent to the system, and terminate the reaction after 0.5 hours. After drying on a rotary evaporator, acetonitrile precipitation treatment and sand core filter organic filter membrane filtration. The obtained solid is a crude product containing 1,4-fullerene derivative 1; the solid crude product is dissolved in toluene, and separated and purified by high performance liquid chromatography, with toluene as the mobile phase, the detection wavelength at 380 nm, and the flow rate at 4 mL / min, using a Buckyprep separation column to obtain a pure product of 1,4-fullerene derivative 1.

[0046] Example 3

[0047] The steps include:

[0048] To the reaction flask, 50 mL of N,N-dimethylformamide, 463 μL of 5-fold molar equivalent of tetrabutylammonium hydroxide (TBAOH) methanol solution (1.5 mol / L), and 208 μL of 10-fold molar equivalent of dimethyl ethylmalonate were added in sequence, and inert argon gas was introduced as a protective gas. The mixture was stirred at room temperature of 25°C for 0.5 h, and then 100 mg of C 60 , continue stirring for 1 hour, then add 1 times the molar equivalent of iodine 35mg to the system, and terminate the reaction after 0.5 hours. After drying on a rotary evaporator, acetonitrile precipitation treatment and sand core filter organic filter membrane filtration. The obtained solid is a crude product containing 1,4-fullerene derivative 2; the solid crude product is dissolved in toluene, and separated and purified by high performance liquid chromatography, with toluene as the mobile phase, the detection wavelength at 380nm, and the flow rate at 4mL / min, using a Buckyprep separation column to obtain a pure product of 1,4-fullerene derivative 2.

[0049] Example 4

[0050] The steps include:

[0051] To the reaction flask, 40 mL of N,N-dimethylformamide, 444 μL of 5-fold molar equivalent of tetrabutylammonium hydroxide (TBAOH) methanol solution (1.5 mol / L), and 102 μL of 5-fold molar equivalent of diethyl ethylmalonate were added in sequence, and inert argon gas was introduced as a protective gas. The mixture was stirred at 45 °C for 1 h, and then 80 mg of C was added. 60, continue stirring for 1 hour, then add 3 times the molar equivalent of iodine 85mg to the system, and terminate the reaction after 0.5h. After drying on a rotary evaporator, acetonitrile precipitation treatment and sand core filter organic filter membrane filtration. The obtained solid is a crude product containing 1,4-fullerene derivative 1; the solid crude product is dissolved in toluene, and separated and purified by high performance liquid chromatography, with toluene as the mobile phase, the detection wavelength at 380nm, and the flow rate at 4mL / min using a Buckyprep separation column, a pure product of 1,4-fullerene derivative 1 can be obtained.

[0052] Example 5

[0053] The steps include:

[0054] To the reaction flask, 80 mL of N,N-dimethylformamide, 555 μL of 3-fold molar equivalent of tetrabutylammonium hydroxide (TBAOH) methanol solution (1.5 mol / L), and 208 μL of 5-fold molar equivalent of dimethyl ethylmalonate were added in sequence, and inert argon gas was introduced as a protective gas. The mixture was stirred at 60 °C for 1 h, and then 200 mg of C 60 , continue stirring for 1 hour, then add 1.5 times the molar equivalent of iodine 106mg to the system, and terminate the reaction after 0.5h. After drying on a rotary evaporator, acetonitrile precipitation treatment and sand core filter organic filter membrane filtration. The resulting solid is a crude product containing 1,4-fullerene derivative 2; the solid crude product is dissolved in toluene, and separated and purified by high performance liquid chromatography, with toluene as the mobile phase, a detection wavelength of 380nm, and a flow rate of 4mL / min using a Buckyprep separation column, to obtain a pure product of 1,4-fullerene derivative 2.

[0055] Example 6

[0056] The steps include:

[0057] To the reaction flask, 40 mL of N,N-dimethylformamide, 666 μL of 3-fold molar equivalent of tetrabutylammonium hydroxide (TBAOH) methanol solution (0.5 mol / L), and 164 μL of 8-fold molar equivalent of diethyl ethylmalonate were added in sequence, and inert argon gas was introduced as a protective gas. The mixture was stirred at 45 °C for 1 h, and then 80 mg of C was added. 60 , continue stirring for 0.5h, then add 1 times the molar equivalent of iodine 28mg to the system, and terminate the reaction after 0.5h. After drying on a rotary evaporator, acetonitrile precipitation treatment and sand core filter organic filter membrane filtration. The obtained solid is a crude product containing 1,4-fullerene derivative 1; the solid crude product is dissolved in toluene, and separated and purified by high performance liquid chromatography, with toluene as the mobile phase, the detection wavelength at 380nm, and the flow rate at 4mL / min using a Buckyprep separation column, a pure product of 1,4-fullerene derivative 1 can be obtained.

[0058] Example 7

[0059] The steps include:

[0060] To the reaction flask, 50 mL of N,N-dimethylformamide, 416 μL of 3-fold molar equivalent of tetrabutylammonium hydroxide (TBAOH) methanol solution (0.5 mol / L), and 83 μL of 8-fold molar equivalent of dimethyl ethylmalonate were added in sequence, and inert argon gas was introduced as a protective gas. The mixture was stirred at 30 °C for 0.5 h, and then 50 mg of C was added. 60 , continue stirring for 0.5h, then add 3 times the molar equivalent of iodine 53mg to the system, and terminate the reaction after 0.5h. After drying on a rotary evaporator, acetonitrile precipitation treatment and sand core filter organic filter membrane filtration. The obtained solid is a crude product containing 1,4-fullerene derivative 2; the solid crude product is dissolved in toluene, and separated and purified by high performance liquid chromatography, with toluene as the mobile phase, the detection wavelength at 380nm, and the flow rate at 4mL / min using a Buckyprep separation column, a pure product of 1,4-fullerene derivative 2 can be obtained.

[0061] 1,4-Fullerene C 60 Derivative 1 1 H NMR and UV-visible absorption spectrum test data are as follows: 1 H NMR (600MHz, CS2 / CDCl3) δ4.74(d,J=7.2Hz,1H),4.68(d,J=7.2Hz,1H),4.58(d,J=7.0Hz,1H),4.55( s, 3H), 4.51 (d, J = 7.2Hz, 1H), 3.27 (dd, J = 20.3, 7.2Hz, 2H), 1.74 (t, J = 7.0Hz, 3H), 1.65-1.61 (m, 6H). like Figure 2 As shown. UV-vis(Toluene)λ max / nm:444,474,688. Figure 3 shown.

[0062] 1,4-Fullerene C 60 Derivative 2 1 H NMR, 13 C NMR and UV-visible absorption spectrum test data are as follows: 1 HNMR (600MHz, in CS2, DMSO-d6 was used as the external lock solvent) δ3.98 (s, 3H), 3.68 (s, 3H), 3.52 (s, 3H), 2.70 (ddq, J = 28.6, 14.3, 7.1Hz, 2H), 1.04 (t, J = 7.3Hz, 3H). like Figure 5 shown. 13 C NMR(150MHz,CS2 / DMSO-d6)δ167.76(1C,C=O),167.39(1C,C=O),151.35(1C),150.98(1C),149. 37(1C),148.22(1C),148.10(1C),147.83(1C),147.74(1C),147.49(1C),146.55(1C),146.49( 1C),146.36(1C),146.25(3C),145.88(2C),145.71(1C),145.11(2C),144.92(1C),144.75(1C) ,144.29(1C),144.13(1C),143.80(2C),143.67(1C),143.53(1C),143.47(2C),143.37(1C),14 3.32(1C),143.21(1C),143.09(1C),142.83(1C),142.62(5C),142.47(1C),142.41(1C),142.3 9(1C),142.38(1C),142.33(1C),142.22(1C),142.02(1C),141.87(1C),141.80(1C),141.73(1 C), 141.59(2C), 140.30(1C), 139.99(1C), 139.95(1C), 139.37(1C), 139.18(2C), 136.84(1C), 80.18(1C), 65.77(1C), 60.71(1C), 53.34(1C), 51.44(1C), 51.21(1C), 29.56(1C), 27.33(1C). Figure 6 As shown. UV-vis(Toluene)λ max / nm:443,472,689. Figure 7 shown.

[0063] All the above-mentioned embodiments are only preferred embodiments of the present invention, and are not exhaustive of the feasible implementations of the present invention. The requirements stated in the claims of this patent are within the scope of protection, and only minor non-creative changes are made to the experimental steps and processes involved in this patent, which are considered to be within the scope of protection of this patent.

Claims

1. A 1,4-fullerene C 60 A derivative, characterized in that The 1,4-fullerene C 60 The chemical structure of the derivative is shown in Formula I, wherein R is selected from a methyl group or an ethyl group.

2. A 1,4-fullerene C as claimed in claim 1 60 A method for preparing a derivative, characterized in that: The method comprises the following steps: adding an organic solvent and a tetrabutylammonium hydroxide solution to a reaction bottle in sequence, introducing an inert gas as a protective gas, adding an ester organic compound, and stirring at 25°C to 60°C for 0.5 to 1h; adding C 60 The reaction solution is stirred for 0.5 to 1 hour, and then iodine is added to the system. The reaction is terminated after 0.5 to 1 hour. The reaction solution is evaporated and desolventized, precipitated with acetonitrile, and filtered to purify the 1,4-fullerene C. 60 derivative.

3. The 1,4-fullerene C according to claim 2 60 A method for preparing a derivative, characterized in that: The organic solvent is N,N-dimethylformamide.

4. The 1,4-fullerene C according to claim 2 60 A method for preparing a derivative, characterized in that: The tetrabutylammonium hydroxide (TBAOH) solution is a tetrabutylammonium hydroxide (TBAOH) methanol solution, and the solution concentration is 0.5 mol / L to 1.5 mol / L.

5. The 1,4-fullerene C according to claim 2 60 A method for preparing a derivative, characterized in that: The inert gas is selected from nitrogen and argon.

6. The 1,4-fullerene C according to claim 2 60 A method for preparing a derivative, characterized in that: The ester organic substance is selected from dimethyl ethyl malonate and diethyl ethyl malonate, and the fullerene C 60 The molar ratio of the ester organic matter is 1:5 to 1:

10.

7. The 1,4-fullerene C according to claim 2 60 A method for preparing a derivative, characterized in that: The reaction temperature is 25°C to 60°C.

8. The 1,4-fullerene C according to claim 2 60 A method for preparing a derivative, characterized in that: The fullerene C 60 The molar ratio of the tetrabutylammonium hydroxide (TBAOH) is 1:3 to 1:

6.

9. The 1,4-fullerene C according to claim 2 60 A method for preparing a derivative, characterized in that: The fullerene C 60 The molar ratio of the iodine to the iodine is 1:1 to 1:

3.

10. The 1,4-fullerene C according to claim 2 60 A method for preparing a derivative, characterized in that: The purification method is a high performance liquid chromatography separation method, which specifically includes: using a semi-preparative Buckyprep separation column, injecting the redissolved fullerene derivative crude product into a high performance liquid chromatography under a toluene mobile phase for separation and purification to obtain a pure product.

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