JPH11322682A - Fullerene derivative - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new fullerene derivative having ability to form thin film or the like, and useful for a photosensor, a photoelectrochemical element, an electrophotographic photoreceptor or the like. SOLUTION: A compound of formula I [x is 1 or 0; R is a group of formula II; (n) is 2-12; Y is a halogen], preferably a compound of formula III. The compound of formula I is obtained, for example, by the following process: at first, a compound of the formula: R and a compound of the formula: Br(CH2 )Br (e.g. 1,4-dibromobutane) are made to react with each other to synthesize Br(CH2 )n (R)x (CH2 )n Br [e.g. a compound of formula IV (n=4)]; subsequently this product is made to react with one equivalent of sodium azide in a polar solvent to synthesize a compound of the formula: N3 (CH2 )n (R)x (CH2 )n Br; further this compound is made to react with fullerene in a solvent such as chlorobenzene to synthesize a compound of formula V; and finally this compound is made to react with trimethylammonium in a solvent such as toluene under shading.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a fullerene derivative, and more particularly to a novel fullerene derivative having properties such as thin film forming properties.

[0002]

2. Description of the Related Art Fullerene (C ₆₀ ) is a carbon compound constituting a soccer ball-shaped truncated icosahedron having 60 carbon atoms consisting of 20 regular hexagons and 12 regular pentagons. This fullerene was predicted by Osawa et al., But in 1985 Kroto and Smalley (Sm
alley) et al. have confirmed its existence, and its characteristic structure has attracted attention.It has been studied extensively as a research subject, and is expected to be a new functional material.For example, its application in optical engineering, electronic engineering, etc. Investigations have been started from the aspect.

At present, it is not easy to obtain a bulk single crystal of fullerene. Therefore, in application development to an optical device, an electronic device, and the like, it is important to form a thin film which can be processed into a desired two-dimensional pattern and thickness from the beginning. Is believed to be. Until now, thinning of fullerene has been performed exclusively using a vacuum evaporation method or a molecular beam epitaxy method. However, in these methods, a thin film must be prepared through complicated steps using expensive equipment.
As a method of forming a thin film, a method of forming a thin film (monomolecular film) at a gas-liquid interface by an LB (Langmuir Blodgett) method and immobilizing the same on an appropriate substrate is compared with a vacuum evaporation method or a molecular beam epitaxy method. Simple. However, in the case of fullerene, since fullerene is a hydrophobic molecule having extremely high cohesiveness, it is very difficult to form a uniform monomolecular film on a gas-liquid interface, and almost no successful examples have been found. Absent. Therefore, a main object of the present invention is to provide fullerene with a property capable of forming a thin film.

[0004]

According to the present invention, the following general formula (A) can be used to achieve the above object.
Is provided. Here, in the formula (A), X is 1 or 0, R is selected from the following (a), (b), (c) or (d), n is an integer of 2 to 12, Y is a halogen atom.

[0005]

Embedded image

A particularly preferred example of the fullerene derivative of the present invention is a fullerene derivative represented by the following general formula (B):
It is an azobenzene derivative.

[0007]

Embedded image

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The fullerene derivative of the present invention can be synthesized according to a reaction scheme as schematically shown in FIG. That is, first, R as defined above is reacted with an alkyl dihalide to synthesize Compound 1 having a long-chain alkane whose both terminals are halogen atoms such as bromine. Next, compound 1 is reacted with 1 equivalent of sodium azide in a polar solvent such as DMF or DMSO to synthesize compound 2.

Thereafter, compound 2 is reacted with fullerene (C ₆₀ ) using a solvent such as chlorobenzene or toluene to synthesize compound 3. Finally, compound 3 can be synthesized by reacting compound 3 with trimethyl ammonium using a solvent such as toluene under light shielding.

The fullerene derivative of the present invention synthesized as described above forms a monomolecular film by the LB method,
It has been found that a stable thin film is formed by being transferred and fixed on a suitable substrate. This is because the quaternary ammonium (hydrophilic) is introduced at the terminal, and the characteristic structure having a rigid aromatic ring in the molecular skeleton prevents the aggregation between fullerene molecules and stabilizes the molecule on the water surface. It is presumed that the sequence is performed.

It has been clarified that a thinned fullerene or a fullerene derivative has photoconductivity. The fullerene derivative of the present invention, which can be easily formed into a thin film,
Alternatively, it is expected that techniques such as modifying a thin film on an electrode can contribute to the development of applications such as a photosensor, a photoelectrochemical element, an electrophotographic photoreceptor, and a solar cell.

Further, the fullerene derivative of the present invention is LB
Applications based on molecular arrangement such as easy formation of a film are also conceivable. For example, by mixing the fullerene derivative of the present invention with the fullerene (C ₆₀ ) itself and changing the properties of the fullerene, it can be used as a means for studying the properties of the fullerene, or exerting a new function on the fullerene. .

[0013]

EXAMPLES Hereinafter, examples will be shown to further clarify the features of the present invention, but the present invention is not limited by these examples. Example 1 Preparation of Fullerene Derivative A fullerene azobenzene derivative of the above formula (B) was synthesized according to the reaction scheme shown in FIG.

(1) Synthesis of Compound 1 4-Hydroxyazobenzene (13.8 g, 0.13 mol) was dissolved in water (300 mL) containing hydrochloric acid (16 g, 0.15 mol), and sodium nitrite (9.9 g) was added at 5 ° C. or lower. , 0.14 mol) aqueous solution (30 mL) was added dropwise to form a diazonium salt. Separately, an aqueous solution of sodium hydroxide (5.1 g, 0.15 mol) and potassium carbonate (19.3 g, 0.15 mol) was prepared, and phenol (14.5 g, 0.15 mol) was dissolved therein. To the diazonium salt prepared above.
After stirring overnight, concentrated hydrochloric acid was added to adjust the pH to 3, and the resulting solid was collected, thoroughly washed with water, and recrystallized with toluene. Yield 4.4 g, 15% yield.

(2) Synthesis of Compound 2 Potassium hydroxide (0.8 g, 14.0 g) was added to ethanol (100 ml).
mmol) and further compound 1 (1.5 g, 7.0 mmol),
1,4-Dibromobutane (12 g, 35 mmol) was added, and the mixture was heated under reflux for 15 hours. After the reaction, the solvent is distilled off under reduced pressure, and ethanol,
After washing with hexane and water, recrystallization was performed with ethanol.
Purification was performed by column chromatography (solvent: chloroform). Yield: 1.6 g, yield: 50%.

(3) Synthesis of Compound 3 Compound 2 (330 mg, 0.68 mmol) was added to dry DMSO (30 mL).
Was dissolved and sodium azide (44 mg, 0.68 mmol) was added. After the reaction, the solution was allowed to cool to room temperature,
Water (200 mL) was added. After extracting Compound 3 with diethyl ether, the solvent was distilled off under reduced pressure to obtain Compound 3. Compound 3 was used for the next reaction without purification.

(4) Synthesis of Compound 4 Chlorobenzene (200 mL) was added to fullerene (C ₆₀ ) (470
Compound 3 (310 mg, 0.65 mmol) in a chlorobenzene solution (40 ml) was added dropwise to the solution in which the compound (0.8 mg, 0.87 mmol) was dissolved. After the reaction, the solution was allowed to cool to room temperature, and the solvent was distilled off under reduced pressure. Compound 4 was separated by column chromatography (solvent: toluene / ethyl acetate = 9: 1) and recrystallized from chloroform / acetone. Yield 50 mg, 6.8%.

(5) Synthesis of Compound 5 Compound 4 (20 mg, 0.017 mmol) was added to dry toluene (25 mL).
l) was dissolved and a large excess of trimethylamine gas was blown thereinto, followed by stirring at room temperature for 1 hour. The resulting precipitate (compound 5) was filtered and washed with toluene. Yield 10 mg, 50%. Identification data of compound 5 Brown solid: IR (KBr, cm ^-1 ); 2928, 1595, 1497, 1244, 114
6, 1053, 837 ¹ H-NMR (DMSO-dδ): δ 1.5-2.2 (m, 8H, C
_{H 2), 8.06 (s,} 8H, CH 3), 3.9-4.2 (m, 8H, CH 2), 7.01-
7.18 (m, 4H, ArH), 7.74 to 7.86 (m, 4H, ArH) Mass spectrometry (SIMS): m / s 1198 (M ⁺ ) Elemental analysis (measured value): C, 81.54; H, 3.03; 4.84
%, Calculated values _{(C 88 H 88 BrN 4 O} 2 · 3/2 ( as _{H 2 O)): C,} 81.88; H, 2.94; N, 4.57%.

Example 2 Physical Properties of Fullerene Derivative Compound 5 synthesized in Example 1 [fullerene derivative of the formula (B)] was prepared using an LB film forming apparatus (FSI manufactured by USI System Co., Ltd.).
(SD-50). From the π-A curve, the limiting molecular occupation area was 0.95 nm ² / mol, and it was confirmed that fullerene formed a monomolecular film.

This film could be transferred to the mica surface by the vertical pulling method. This is AFM (atomic force microscope)
As a result, a thin film having a thickness of about 3 nm was formed. Further, when the solubility of the fullerene derivative of the present invention was examined, water and common organic solvents (for example, toluene,
Chloroform, alcohol), but not DMS
It was found to be soluble in O, DMF, benzyl alcohol and pyridine.

[Brief description of the drawings]

FIG. 1 is a diagram generally showing a reaction scheme for synthesizing a fullerene derivative of the present invention.

FIG. 2 shows a reaction scheme for synthesizing a particularly preferred example of the fullerene derivative of the present invention.

Claims (2)

[Claims] 1. A fullerene derivative represented by the following general formula (A) [wherein X is 1 or 0, and R is the following (a), (b), It is selected from (c) or (d), n is an integer of 2 to 12, and Y is a halogen atom. [Formula 1] 2. A fullerene-azobenzene derivative represented by the following formula (B). Embedded image