JP2018203686A - Fullerene derivative and lubricant - Google Patents

Abstract

To provide a fullerene derivative capable of forming a lubricant layer high in bonded ratio.SOLUTION: There is provided a fullerene derivative represented by the following structure formula for example.SELECTED DRAWING: None

Description

  The present invention relates to a fullerene derivative and a lubricant.

  Perfluoropolyether compounds have excellent heat resistance, chemical resistance, and oxidation resistance, and have a large viscosity index, so there is little change in fluidity (viscosity) in a wide temperature range from low to high temperatures, and good lubricity. Demonstrate. In addition to being nonflammable, perfluoropolyether compounds have little effect on polymer materials such as rubber and plastic, low vapor pressure and low evaporation loss, low surface tension, and high electrical insulation. It is also known that it exhibits high performance over a very wide range as a lubricant. For this reason, perfluoropolyether compounds are widely used in vacuum pump oils as lubricants, lubricants such as magnetic disks / tapes, heat media, non-adhesives, and other applications.

On the other hand, C ₆₀ which is a kind of fullerene is known to be useful as a lubricant.

In Non-Patent Document 1, the friction coefficient of the silicon substrate formed with the deposited film of C ₆₀ is confirmed to be reduced. Non-Patent Document 1 also proposes a fullerene derivative in which a perfluoropolyether group is introduced into fullerene, but does not describe a specific compound or a synthesis method thereof.

Furthermore, C ₆₀ is known to exhibit excellent properties as an additive to conventional lubricating oils.

In Non-Patent Document 2, it is measured as those painted ordinary lubricating oil to the surface of the copper foil, the frictional resistance but painted those of C ₆₀ was added 5% to the oil. Friction resistance is measured by rubbing a steel roller while applying a load. As a result, the case of adding C _60, the wear resistance as compared with the case of not adding it has been confirmed to be improved.

  Patent Document 1 describes a lubricant comprising a mixture of fullerene, a fullerene carboxyl derivative or a fullerene derivative to which an ester group is bonded, and a perfluoropolyether compound.

  Patent Documents 2 to 6 describe a lubricant comprising a fullerene derivative having a perfluoropolyether group in a ring structure condensed with fullerene. These fullerene derivatives are characterized by a molecular structure in which one ring structure is condensed over two adjacent carbon atoms on the fullerene skeleton.

  On the other hand, Patent Document 7 and Non-Patent Document 3 describe a modification reaction of fullerene, characterized in that an organic copper reagent prepared from a Grignard reagent and a copper compound is reacted with fullerene.

  Patent Document 8 describes a compound synthesized by the methods described in Patent Document 7 and Non-Patent Document 3, and a part of the compound is soluble in a general organic solvent such as hexane. Is described.

  Furthermore, Non-Patent Document 4 and Non-Patent Document 5 utilized derivatives having a total of five perfluoroalkyl groups on the fullerene skeleton synthesized by the methods described in Patent Document 7 and Non-Patent Document 3. The formation of vesicles is described.

  However, the use of the above compound as a lubricant is not described.

JP 2006-131874 A Japanese Patent No. 5600202 Japanese Patent No. 5600222 International Publication No. 2015/125940 International Publication No. 2017/006812 JP 2017-14192A Japanese Patent No. 4699233 Japanese Patent No. 4109458

Appl. Phys. Lett. 62, 3253 (1993) Russian Journal of Applied Chemistry 75, 1330 (2002) Chem. Rev. 108, 3016 (2008) Angew. Chem. Int. Ed. 49, 1665 (2010) J. Am. Chem. Soc. 133, 6364 (2011)

  In general, even when a compound having a fullerene skeleton is used as a lubricant, the compound having a fullerene skeleton is likely to aggregate, so that good dispersibility cannot be obtained and sufficient wear resistance cannot be imparted to the object. There is a problem.

  In Patent Document 1, fullerene or a fullerene derivative and a perfluoropolyether compound have insufficient affinity and are likely to aggregate. Therefore, a mixture of fullerene or a fullerene derivative and a perfluoropolyether compound is used as a lubricant. However, there is a problem that sufficient wear resistance cannot be imparted to the object.

  Patent Documents 2 to 6 propose fullerene derivatives having a fullerene skeleton and a perfluoropolyether group in order to solve the above-described problems. In the fullerene derivatives described in Patent Documents 2 to 6, the ring structure introduced on the fullerene skeleton to give a perfluoropolyether group is condensed over two carbon atoms on the fullerene skeleton. It is characterized by being.

  On the other hand, when a lubricant layer is formed on the surface of a carbon protective film of a magnetic recording medium such as a hard disk, some lubricant that is not adsorbed on the surface of the carbon protective film is removed every time the head flies. As a result, there is a risk that the lubricant will gradually become thinner and eventually lead to a crash. In order to prevent such a phenomenon, it is necessary that the amount of lubricant adsorbed on the surface of the carbon protective film is higher than a predetermined ratio, that is, the bond ratio of the lubricant layer is high.

  The bonded ratio of the lubricant layer is the ratio of the lubricant remaining after the hard disk on which the lubricant layer is formed is immersed in a solvent to wash away the lubricant that is not adsorbed on the surface of the carbon protective film.

  The fullerene derivatives described in Patent Documents 2 to 6 need to increase the number of perfluoropolyether groups in order to improve lubricity. For this purpose, it is conceivable to increase the number of ring structures. However, since the ring structures are condensed over two carbon atoms on the fullerene skeleton, the number of ring structures increases as the number of ring structures increases. The surface area of the π-conjugated system that contributes to is reduced. In addition, when multiple ring structures are provided on the fullerene skeleton, the ring structures are likely to be formed at positions distant from each other due to thermodynamic factors. This is a factor that reduces the surface area of the π-conjugated system on the fullerene skeleton. It becomes.

  From the above, even when a compound having a fullerene skeleton is used as a lubricant, the surface area of the π-conjugated system on the fullerene skeleton that contributes to adsorption is insufficient, so that a lubricant layer having a high bond ratio can be formed. There is a problem that it is difficult.

  One embodiment of the present invention has been made in view of the above circumstances, and an object thereof is to provide a fullerene derivative capable of forming a lubricant layer having a high bond ratio.

That is, the present invention includes the following configurations.
[1] General formula

（式中、ＦＬＮはフラーレン骨格であり、Ａは、一般式
Ａ_１−ＣＨ_２−Ｏ−・・・（Ａ）
（式中、Ａ_１は、１価のパーフルオロポリエーテル基である。）
で表される基、または、一般式
Ａｒ−ＣＯＯ−ＣＨ_２−Ａ_２−ＣＨ_２−ＯＣＯ−・・・（Ｂ）
（式中、Ａｒはアリール基またはアラルキル基であり、Ａ_２は、２価のパーフルオロポリエーテル基である。）
で表される基であり、Ｒは水素原子またはメチル基であり、ｋは５〜１０の整数であり、ｍは０〜２の整数であり、ｎは１〜５の整数である。）
で表される化合物であるフラーレン誘導体。
［２］前記フラーレン骨格がＣ_６０である［１］に記載のフラーレン誘導体。
［３］前記Ａ_１及びＡ_２のパーフルオロポリエーテル基の炭素数が５〜１００である［１］または［２］に記載のフラーレン誘導体。
［４］前記Ａ_１及びＡ_２のパーフルオロポリエーテル基が、一般式
−（ＣＦ_２）_ｘＯ−・・・（Ｃ）
（式中、ｘは１〜５の整数である。）
で表される基を含む［１］〜［３］のいずれか一項に記載のフラーレン誘導体。
［５］前記Ａ_１及びＡ_２のパーフルオロポリエーテル基は、前記ｘが１または２である前記一般式（Ｃ）で表される基を１〜５０個含む［４］に記載のフラーレン誘導体。
［６］前記Ａ_１及びＡ_２のパーフルオロポリエーテル基の平均式量が２５０〜６０００の範囲内である［１］〜［５］のいずれか一項に記載のフラーレン誘導体。
［７］前記Ａ_１及びＡ_２のパーフルオロポリエーテル基が直鎖である［１］〜［６］のいずれか一項に記載のフラーレン誘導体。
［８］前記ｋが５または１０である［１］〜［７］のいずれか一項に記載のフラーレン誘導体。
［９］化学式

(In the formula, FLN is a fullerene skeleton, and A is a general formula A ₁ —CH ₂ —O— (A)
(In the formula, A ₁ is a monovalent perfluoropolyether group.)
Or a group represented by the general formula Ar—COO—CH ₂ —A ₂ —CH ₂ —OCO— (B)
(In the formula, Ar is an aryl group or an aralkyl group, and A ₂ is a divalent perfluoropolyether group.)
R is a hydrogen atom or a methyl group, k is an integer of 5 to 10, m is an integer of 0 to 2, and n is an integer of 1 to 5. )
The fullerene derivative which is a compound represented by these.
Fullerene derivative according to [2] the fullerene skeleton is a _{C 60} [1].
[3] The fullerene derivative according to [1] or [2], wherein the perfluoropolyether group of A ₁ and A ₂ has 5 to 100 carbon atoms.
[4] The perfluoropolyether group of A ₁ and A ₂ is represented by the general formula — (CF ₂ ) _x O— (C).
(In the formula, x is an integer of 1 to 5.)
Fullerene derivative as described in any one of [1]-[3] containing group represented by these.
[5] The fullerene derivative according to [4], wherein the perfluoropolyether group of A ₁ and A ₂ includes 1 to 50 groups represented by the general formula (C), wherein x is 1 or 2. .
[6] The fullerene derivative according to any one of [1] to [5], wherein an average formula weight of the perfluoropolyether groups of A ₁ and A ₂ is in a range of 250 to 6000.
[7] The fullerene derivative according to any one of [1] to [6], wherein the perfluoropolyether groups of A ₁ and A ₂ are linear.
[8] The fullerene derivative according to any one of [1] to [7], wherein k is 5 or 10.
[9] Chemical formula

（式中、Ａ_１は、１価のパーフルオロポリエーテル基である。）
で表される化合物、化学式

(In the formula, A ₁ is a monovalent perfluoropolyether group.)
A compound represented by the chemical formula

（式中、Ａ_２は、２価のパーフルオロポリエーテル基である。）
で表される化合物、化学式

(In the formula, A ₂ is a divalent perfluoropolyether group.)
A compound represented by the chemical formula

（式中、Ａ_２は、２価のパーフルオロポリエーテル基である。）
で表される化合物、化学式

(In the formula, A ₂ is a divalent perfluoropolyether group.)
A compound represented by the chemical formula

（式中、Ａ_２は、２価のパーフルオロポリエーテル基である。）
で表される化合物、または、化学式

(In the formula, A ₂ is a divalent perfluoropolyether group.)
Or a chemical formula represented by

（式中、Ａ_２は、２価のパーフルオロポリエーテル基である。）
で表される化合物である［１］〜［８］のいずれか一項に記載のフラーレン誘導体。
［１０］［１］〜［９］のいずれか一項に記載のフラーレン誘導体を含有する潤滑剤。
［１１］フラーレン骨格を有しないパーフルオロポリエーテル化合物をさらに含有する［１０］に記載の潤滑剤。
［１２］一般式

(In the formula, A ₂ is a divalent perfluoropolyether group.)
The fullerene derivative according to any one of [1] to [8], which is a compound represented by:
[10] A lubricant containing the fullerene derivative according to any one of [1] to [9].
[11] The lubricant according to [10], further comprising a perfluoropolyether compound having no fullerene skeleton.
[12] General formula

（式中、ＦＬＮはフラーレン骨格であり、Ａ_２は、２価のパーフルオロポリエーテル基であり、Ｒは水素原子またはメチル基であり、ｋは５〜１０の整数であり、ｍは０〜２の整数であり、ｎは１〜５の整数である。）
で表される化合物であるフラーレン誘導体。
［１３］化学式

(In the formula, FLN is a fullerene skeleton, A ₂ is a divalent perfluoropolyether group, R is a hydrogen atom or a methyl group, k is an integer of 5 to 10, and m is 0 to 0. 2 is an integer, and n is an integer of 1 to 5.)
The fullerene derivative which is a compound represented by these.
[13] Chemical formula

（式中、Ａ_２は、２価のパーフルオロポリエーテル基である。）
で表される化合物、化学式

(In the formula, A ₂ is a divalent perfluoropolyether group.)
A compound represented by the chemical formula

（式中、Ａ_２は、２価のパーフルオロポリエーテル基である。）
で表される化合物、化学式

(In the formula, A ₂ is a divalent perfluoropolyether group.)
A compound represented by the chemical formula

（式中、Ａ_２は、２価のパーフルオロポリエーテル基である。）
で表される化合物、または、化学式

(In the formula, A ₂ is a divalent perfluoropolyether group.)
Or a chemical formula represented by

（式中、Ａ_２は、２価のパーフルオロポリエーテル基である。）
で表される化合物である［１２］に記載のフラーレン誘導体。

(In the formula, A ₂ is a divalent perfluoropolyether group.)
The fullerene derivative according to [12], which is a compound represented by the formula:

  One embodiment of the present invention can provide a fullerene derivative capable of forming a lubricant layer with a high bond ratio.

  The configuration of the embodiment of the present invention will be described below. The present invention can be implemented with appropriate modifications without departing from the scope of the invention.

(Fullerene derivative)
The fullerene derivative of the present embodiment has a general formula

（式中、ＦＬＮはフラーレン骨格であり、Ａは、一般式
Ａ_１−ＣＨ_２−Ｏ−・・・（Ａ）
（式中、Ａ_１は、１価のパーフルオロポリエーテル基である。）
で表される基、または、一般式
Ａｒ−ＣＯＯ−ＣＨ_２−Ａ_２−ＣＨ_２−ＯＣＯ−・・・（Ｂ）
（式中、Ａｒはアリール基またはアラルキル基であり、Ａ_２は、２価のパーフルオロポリエーテル基である。）
で表される基であり、Ｒは水素原子またはメチル基であり、ｋは５〜１０の整数であり、ｍは０〜２の整数であり、ｎは１〜５の整数である。）
で表されるフラーレン誘導体、並びに、これらフラーレン誘導体の合成に際し、中間体となりうるパーフルオロポリエーテル基を有するフラーレン誘導体である。

(In the formula, FLN is a fullerene skeleton, and A is a general formula A ₁ —CH ₂ —O— (A)
(In the formula, A ₁ is a monovalent perfluoropolyether group.)
Or a group represented by the general formula Ar—COO—CH ₂ —A ₂ —CH ₂ —OCO— (B)
(In the formula, Ar is an aryl group or an aralkyl group, and A ₂ is a divalent perfluoropolyether group.)
R is a hydrogen atom or a methyl group, k is an integer of 5 to 10, m is an integer of 0 to 2, and n is an integer of 1 to 5. )
And a fullerene derivative having a perfluoropolyether group that can be an intermediate in the synthesis of these fullerene derivatives.

  However, hereinafter, when the synthesis of the fullerene derivative is not mentioned, the former fullerene derivative is simply referred to as “fullerene derivative”.

  The perfluoropolyether group is a group in which a plurality of fluorocarbon groups are bonded by an ether bond.

  The fullerene derivative of the present embodiment has k benzene-derived groups on the fullerene skeleton, and each of the k benzene-derived groups is represented by n general formulas (A), or Since it is substituted with the group represented by the general formula (B), it is possible to form a lubricant layer having a high bond ratio.

  The k benzene-derived groups on the fullerene skeleton may be the same or at least partially different.

The perfluoropolyether group of A ₁ and A ₂ has the general formula — (CF ₂ ) _x O— (C)
(In the formula, x is an integer of 1 to 5.)
It is preferable that the group represented by these is included.

Moreover, it is more preferable that the perfluoropolyether groups of A ₁ and A ₂ include 1 to 50 groups represented by the general formula (C) where x is 1 or 2. This is because an organic fluorine compound having such a structure is manufactured industrially, can be easily obtained, and is easily used industrially.

In the fullerene derivative of the present embodiment, the perfluoropolyether group of A ₁ and A ₂ has a group represented by the general formula (C), so that the perfluoropolyether group is represented by the general formula (C). With respect to a fullerene derivative having no group, the solubility in a fluorine-based solvent is increased, and as a result, the fullerene derivative can be uniformly coated on the surface to be coated.

In addition, the groups represented by the general formula (C) contained in the perfluoropolyether groups of A ₁ and A ₂ may be the same or at least partially different.

  In addition, the group represented by the general formula (C) may be bonded to the fullerene skeleton in any direction via an aromatic ring or the like.

Preferably the number of carbon atoms of the perfluoro polyether groups of A ₁ and _{A 2} is 5 to 100, and more preferably from 5 to 40. When the perfluoropolyether group has 5 to 100 carbon atoms, it has good solubility in a fluorine-based solvent, is easy to apply, and has sufficient solubility in a general organic solvent. Easy to convert.

The average formula amount (Mn) of the A ₁ and A ₂ perfluoropolyether groups is preferably in the range of 250 to 6000, and more preferably in the range of 280 to 3000. When the average formula amount (Mn) of the perfluoropolyether group of A ₁ and A ₂ is 250 to 6000, the solubility in a fluorine-based solvent is good, the coating is easy, and the addition to a general organic solvent is possible. Since the solubility is sufficient, the structure is easily converted by an organic reaction.

The perfluoropolyether group of A ₁ and A ₂ may be either linear or branched, but is preferably linear.

In the fullerene derivative of this embodiment, the perfluoropolyether group of A ₁ and A ₂ is linear, so that lubricity and solubility in a fluorine-based solvent are improved.

  The perfluoropolyether group may have a substituent as necessary.

When A is a group represented by the general formula (A), the structure of the non-bonding end of A ₁ , that is, the terminal that is not a part bonded to the fullerene skeleton through a group derived from benzene, etc. Examples thereof include perfluoroalkyl groups such as a trifluoromethyl group and a perfluorobutyl group.

  When A is a group represented by the general formula (B), examples of Ar include aryl groups such as a phenyl group and a naphthyl group, and aralkyl groups such as a benzyl group and a phenylpropyl group.

Examples of the fullerene skeleton in the fullerene derivative of the present embodiment include a C ₆₀ skeleton, a C ₇₀ skeleton, a C ₇₆ skeleton, a C ₇₈ skeleton, and a higher order fullerene skeleton. Among these, _C60 skeleton is preferable.

A C ₆₀ skeleton having a higher purity than other fullerene skeletons can be easily obtained industrially. For this reason, the fullerene derivative of this embodiment can make purity high, and can make lubricity and smoothness favorable.

  In the fullerene derivative of the present embodiment, k is preferably 5 or 10. Such compounds are easy to synthesize with a relatively small number of steps.

  When m is 2, the fullerene derivative of this embodiment may have two hydrogen atoms or methyl groups on the fullerene skeleton, or may have one hydrogen atom and one methyl group. Good.

(Synthesis method of fullerene derivative)
The fullerene derivative of this embodiment can be synthesized, for example, according to the following two kinds of synthesis methods.

[When A is a group represented by the general formula (A)]
The fullerene derivative of the present embodiment is, for example, organic copper prepared from phenyl iodide having a group represented by the general formula (A), isopropylmagnesium chloride-lithium chloride complex, and copper (I) bromide-dimethylsulfide complex. It can be synthesized from reagents and fullerenes.

  The above reaction can be carried out in a solvent.

  The reaction solvent for preparing the organocopper reagent is not particularly limited as long as it is a solvent capable of stabilizing the organometallic species. For example, diethyl ether, tetrahydrofuran (hereinafter referred to as “THF”) may be used. And ether solvents such as

  The reaction solvent for the addition reaction using an organic copper reagent and fullerene as a starting material is not particularly limited as long as it is a solvent capable of dissolving fullerene and stabilizing the organic copper reagent. For example, THF And a mixed solvent of o-dichlorobenzene (hereinafter sometimes referred to as “ODCB”).

  The above reaction is preferably carried out in an inert gas atmosphere with stirring. By carrying out the above reaction in an inert gas atmosphere, generation of by-products can be suppressed.

  The preparation of the organic copper reagent is preferably performed at −20 ° C. or lower because the organic copper reagent is thermally unstable.

  Further, the addition reaction of the organic copper reagent to fullerene is preferably carried out while heating if the reaction rate is not sufficient.

  After adding a Brönsted acid such as a saturated aqueous ammonium chloride solution or a methylating agent such as iodomethane to the reaction mixture, the mixture is filtered through Celite while flowing a fluorine-containing solvent such as AK225 (Asahi Glass Co., Ltd.), and the reaction solvent and A crude product can be obtained by distilling off the elution solvent.

[When A is a group represented by Formula (B)]
The fullerene derivative of the present embodiment is prepared from, for example, an aryl iodide having an alkoxycarbonyl group such as a methoxycarbonyl group or an ethoxycarbonyl group, an isopropylmagnesium chloride-lithium chloride complex, and a copper (I) bromide-dimethylsulfide complex. A fullerene derivative synthesized from an organic copper reagent and fullerene can be synthesized as a precursor.

  Specifically, the fullerene derivative of the present embodiment has a general formula

（式中、ＦＬＮ、Ｒ、ｋ、ｍ、ｎは、一般式（１）と同一であり、Ｒ^１はメチル基、エチル基などの炭化水素基である。）
で表される化合物から合成することができる。

(In the formula, FLN, R, k, m, and n are the same as those in the general formula (1), and R ¹ is a hydrocarbon group such as a methyl group or an ethyl group.)
It can synthesize | combine from the compound represented by these.

  The reaction for synthesizing the compound represented by the general formula (2) can be carried out in a solvent.

  The reaction solvent for preparing the organocopper reagent is not particularly limited as long as it is a solvent capable of stabilizing the organometallic species, and examples thereof include ether solvents such as diethyl ether and THF.

  The reaction solvent for adding the organic copper reagent to the fullerene is not particularly limited as long as it is a solvent capable of dissolving the fullerene and stabilizing the organic copper reagent, but for example, a mixture of THF and ODCB. A solvent etc. can be mentioned.

  The above reaction is preferably carried out in an inert gas atmosphere with stirring. By carrying out the above reaction in an inert gas atmosphere, generation of by-products can be suppressed.

  The preparation of the organic copper reagent is preferably performed at −20 ° C. or lower because the organic copper reagent is thermally unstable.

  Further, the addition reaction of the organic copper reagent is preferably carried out while heating if the reaction rate is not sufficient.

  After adding a Brönsted acid such as saturated aqueous ammonium chloride or a methylating agent such as iodomethane to the reaction mixture, the mixture is filtered through Celite while flowing an organic solvent known to dissolve fullerene derivatives such as toluene. A crude product can be obtained by distilling off the reaction solvent and the elution solvent with an evaporator.

Next, chemical formula R ¹ OCO— of the compound represented by the general formula (2)
In the presence of an acid catalyst, the group represented by general formula HOCH ₂ -A ₂ -CH ₂ OH (3)
(In the formula, A ₂ is the same as in the general formula (1).)
By transesterification with a compound represented by the general formula

（式中、ＦＬＮ、Ａ_２、Ｒ、ｋ、ｍ、ｎは、一般式（１）と同一である。）
で表される化合物（中間体）を得ることができる。

(In the formula, FLN, A ₂ , R, k, m, and n are the same as those in the general formula (1).)
The compound (intermediate) represented by these can be obtained.

  In the above reaction, as the acid catalyst, generally known inorganic acids and organic acids can be used. For example, hydrochloric acid, sulfuric acid, methanesulfonic acid, p-toluenesulfonic acid, trifluoromethanesulfonic acid (hereinafter referred to as “TfOH”). Or the like.)).

  As the compound represented by the general formula (3), industrially produced compounds can be used, and examples thereof include Fomblin (registered trademark) series (manufactured by Solvay Specialty Polymers).

  The above reaction can be carried out in a solvent.

  The solvent is not particularly limited as long as it can dissolve the compound represented by the general formula (2) and the compound represented by the general formula (3). For example, toluene, xylene, ODCB An aromatic solvent capable of dissolving a fullerene derivative such as hexafluorobenzene, AK-225 (manufactured by Asahi Glass Co., Ltd.), hexafluorotetrachlorobutane (hereinafter sometimes referred to as “HFTCB”) and the like. The mixed solvent with a fluorine-type solvent can be mentioned.

  The above reaction is preferably carried out in an inert gas atmosphere while heating and stirring. By carrying out the above reaction in an inert gas atmosphere, generation of by-products can be suppressed.

  The reaction is preferably carried out while attaching a Soxhlet extractor equipped with a glass fiber cylindrical filter paper containing molecular sieves, heating to a temperature exceeding the boiling point of the solvent used, and refluxing the solvent. By removing alcohol with a small molecular weight such as methanol as a by-product by such a method, the transesterification reaction can proceed efficiently.

  After cooling the reaction mixture to room temperature and neutralizing it appropriately by adding aqueous ammonia, the reaction solvent is distilled off by a rotary evaporator, and the resulting mixture is dissolved in a fluorine-based solvent such as AK-225 (Asahi Glass Co., Ltd.). The crude product can be obtained by removing the impurities such as unreacted fullerene or fullerene derivative by filtering and removing the solvent again.

Finally, by performing a known reaction on the compound (intermediate) represented by the general formula (1 ′), the general formula HO—CH ₂ —A ₂ —CH ₂ —OC—
The non-bonded end of the group represented by the formula, that is, the hydroxyl group is represented by the general formula ArOCO-
(In the formula, Ar is the same as in the general formula (1).)
A crude product can be obtained by converting to a group represented by:

  The crude product obtained by the above two kinds of synthesis methods can be used as a lubricant. However, when higher purity is required, the crude product is further purified by silica gel column chromatography or carbon dioxide. After being purified by a supercritical fluid extraction method or the like, it can be used as a lubricant.

  Carbon dioxide supercritical fluid extraction is a method in which a crude product is placed in a pressure vessel and liquefied carbon dioxide flows into the pressure vessel while maintaining the pressure and temperature in the pressure vessel. In this state, the target compound is purified by extraction into supercritical carbon dioxide.

  The temperature in the pressure vessel is preferably 31 ° C. or higher and 80 ° C. or lower. When the temperature in the pressure vessel is less than 31 ° C, carbon dioxide does not enter a supercritical state, and when it exceeds 80 ° C, the extraction power of supercritical carbon dioxide becomes weak.

  Moreover, it is preferable that the pressure in a pressure vessel is 7.38 MPa or more and 30 MPa or less. When the pressure in the pressure vessel is less than 7.38 MPa, the carbon dioxide does not enter a supercritical state, and when it exceeds 30 MPa, the pressure resistance performance of the device is required, which increases the price of the device. Manufacturing cost increases.

(lubricant)
The lubricant of this embodiment contains the fullerene derivative of this embodiment. As the lubricant of the present embodiment, the fullerene derivative of the present embodiment may be used alone, or in addition to the fullerene derivative of the present embodiment, other lubricants may be used as long as the effect of the lubricant of the present embodiment is not impaired. An additive or an additive generally used for a lubricant may be further contained.

  Although it does not specifically limit as another lubricant, For example, the perfluoro polyether compound which does not have a fullerene skeleton can be mentioned.

  Examples of perfluoropolyether compounds having no fullerene skeleton include Fomblin (registered trademark) series (manufactured by Solvay Specialty Polymers).

  Since the fullerene derivative of this embodiment has a perfluoropolyether group, it has high affinity with a perfluoropolyether compound having no fullerene skeleton. Therefore, even when the lubricant of this embodiment contains the fullerene derivative of this embodiment and a perfluoropolyether compound having no fullerene skeleton, the fullerene derivative of this embodiment is uniform in the lubricant of this embodiment. Can be dispersed or dissolved.

  Further, when the lubricant of the present embodiment contains the fullerene derivative of the present embodiment and a perfluoropolyether compound having no fullerene skeleton, the content of the fullerene derivative in the lubricant is 0.1% by mass or more and 100 %, More preferably 1% by mass or more and less than 100%, and particularly preferably 10% by mass or more and less than 100%. Thereby, the better adsorptivity to the surface where the lubricant is applied can be expressed.

  The lubricant of this embodiment can be used by being applied to the surface of a magnetic recording medium such as a hard disk.

  The method for applying the lubricant is not particularly limited, and for example, a spin coating method, a dip method, or the like can be used.

  When applying the lubricant to the surface of the magnetic recording medium using the dip method, for example, after immersing the magnetic recording medium in a lubricant solution placed in the immersion tank of the dip coater, the magnetic recording medium is removed from the immersion tank. Pull up at a predetermined speed.

  The concentration of the fullerene derivative in the lubricant solution is preferably 0.0001% by mass or more.

  The present invention will be specifically described below based on examples. In addition, this invention is not limited only to an Example.

⁽¹ H-NMR)
A sample (about 10 mg to ₃₀ mg) was dissolved in a CDCl ₃ / hexafluorobenzene mixed solvent (about 0.5 mL) and then put into an NMR sample tube having a diameter of 5 mm, and ¹ H-NMR analysis was performed under the following conditions. .

Apparatus: Fourier transform nuclear magnetic resonance apparatus JNM-EX270 (manufactured by JEOL Ltd.)
Measurement temperature: room temperature At this time, tetramethylsilane was added as a reference substance to the CDCl ₃ / hexafluorobenzene mixed solvent.

(MS)
A sample (about 1 mg) was dissolved in toluene (about 0.5 mL), then filtered through a membrane filter, and mass spectrometry was performed under the following conditions.

Apparatus: Quadrupole LC / MS system Agilent 6120 (manufactured by Agilent Technologies)
Ionization conditions: APCI-
Example 1
The fullerene derivative of this embodiment was produced according to the following synthesis example.

(Synthesis Example 1)
Synthesis of Compound 1 (C1): [Reaction Formula (3)]
Fluorinated triethylene glycol monomethyl ether (Exfluor, 10 g, 25 mmol, perfluoropolyether group formula 367) and pyridine (2.4 g, 30 mmol) were added to dichloromethane (100 mL), and trifluoromethane was added to the resulting solution. A solution of sulfonic anhydride (8.8 g, 31 mmol) in dichloromethane (30 mL) was added dropwise. The resulting mixture was stirred at room temperature for 20 hours, and then the reaction mixture was washed once with pure water (100 mL) and saturated aqueous sodium carbonate solution (100 mL). The obtained organic layer was filtered and then concentrated by a rotary evaporator to obtain Compound 1 (C1) (13 g, 24 mmol, yield 95%) as a pale yellow oily substance.

The pale yellow oily substance was confirmed to be the compound 1 represented by the following chemical formula (C1) from the analysis result of ¹ H-NMR.

¹ H-NMR δ [ppm]: 4.72 (t, 2H).

（合成例２）
化合物２（Ｃ２）の合成：［反応式（４）］
合成例１で得た化合物１（２．４ｇ、４．５ｍｍｏｌ）と４−ヨードフェノール（０．９０ｇ、４．１ｍｍｏｌ）とをＮ，Ｎ−ジメチルホルムアミド（２０ｍＬ）に加え、得られた溶液に炭酸セシウム（２．１ｇ、６．５ｍｍｏｌ）を加えた。得られた混合物を室温で１８時間攪拌した後、反応混合物をロータリーエバポレーターで濃縮した。得られた混合物を純水（３０ｍＬ）と酢酸エチル（３０ｍＬ）を用いて分液し、さらに水層を酢酸エチル（２０ｍＬ）で二度抽出した。得られた有機層を水洗し、硫酸マグネシウムにより乾燥した。濾過した後、ロータリーエバポレーターで濃縮することで、褐色油状の粗生成物（２．６ｇ）を得た。シリカゲルカラムクロマトグラフィー（展開溶媒：ヘキサン−酢酸エチル（２４：１））で粗生成物を精製することで、無色油状物質として、化合物２（Ｃ２）（２．３ｇ、３．８ｍｍｏｌ、収率９４％）を得た。

(Synthesis Example 2)
Synthesis of Compound 2 (C2): [Reaction Formula (4)]
Compound 1 (2.4 g, 4.5 mmol) obtained in Synthesis Example 1 and 4-iodophenol (0.90 g, 4.1 mmol) were added to N, N-dimethylformamide (20 mL), and the resulting solution was added. Cesium carbonate (2.1 g, 6.5 mmol) was added. The resulting mixture was stirred at room temperature for 18 hours, and then the reaction mixture was concentrated on a rotary evaporator. The obtained mixture was separated using pure water (30 mL) and ethyl acetate (30 mL), and the aqueous layer was extracted twice with ethyl acetate (20 mL). The obtained organic layer was washed with water and dried over magnesium sulfate. After filtration, the mixture was concentrated by a rotary evaporator to obtain a brown oily crude product (2.6 g). The crude product was purified by silica gel column chromatography (developing solvent: hexane-ethyl acetate (24: 1)) to give Compound 2 (C2) (2.3 g, 3.8 mmol, yield 94) as a colorless oily substance. %).

The colorless oily substance was confirmed to be the compound 2 represented by the following chemical formula (C2) from the analysis result of ¹ H-NMR.

¹ H-NMR δ [ppm]: 4.32 (t, 2H), 6.71 (d, 2H), 7.61 (d, 2H).

（合成例３）
化合物３（Ｃ３）の合成：［反応式（５）］
合成例２で得た化合物２（０．３０ｇ、０．５０ｍｍｏｌ）とＴＨＦ（１０ｍＬ）の混合物を−２０℃まで冷却し、イソプロピルマグネシウムクロリド−塩化リチウム錯体のＴＨＦ溶液（約１４質量％、０．７ｍＬ、０．６ｍｍｏｌ）を滴下した。得られた混合物を−２０℃で３０分攪拌した後、臭化銅（Ｉ）−ジメチルスルフィド錯体（０．１３ｇ、０．６１ｍｍｏｌ）のＴＨＦ（５ｍＬ）懸濁液を加えた。得られた混合物を３５℃まで加熱した後、Ｃ_６０フラーレン（５１ｍｇ、７０μｍｏｌ）のＯＤＣＢ（１０ｍＬ）溶液を加えた。得られた混合物を６０℃で９０分攪拌した後、室温まで冷却し、ヨードメタン（１ｍＬ）を加えた。濾過した後、ロータリーエバポレーターで濃縮することで、橙色固体状の粗生成物（８８ｍｇ）を得た。シリカゲルカラムクロマトグラフィー（展開溶媒：ヘキサン−酢酸エチル（１７：３））で粗生成物を精製することで、橙色固体状物質として、化合物３（Ｃ３）（１５ｍｇ、４．８μｍｏｌ、収率７％）を得た。

(Synthesis Example 3)
Synthesis of Compound 3 (C3): [Reaction Formula (5)]
A mixture of Compound 2 (0.30 g, 0.50 mmol) obtained in Synthesis Example 2 and THF (10 mL) was cooled to −20 ° C., and a THF solution of an isopropylmagnesium chloride-lithium chloride complex (about 14% by mass, 0.1%). 7 mL, 0.6 mmol) was added dropwise. The resulting mixture was stirred at −20 ° C. for 30 minutes, and then a suspension of copper (I) bromide-dimethyl sulfide complex (0.13 g, 0.61 mmol) in THF (5 mL) was added. After the resulting mixture was heated to 35 ° C., a solution of C ₆₀ fullerene (51 mg, 70 μmol) in ODCB (10 mL) was added. The resulting mixture was stirred at 60 ° C. for 90 minutes, cooled to room temperature, and iodomethane (1 mL) was added. After filtration, the mixture was concentrated by a rotary evaporator to obtain an orange solid crude product (88 mg). The crude product was purified by silica gel column chromatography (developing solvent: hexane-ethyl acetate (17: 3)) to give Compound 3 (C3) (15 mg, 4.8 μmol, yield 7%) as an orange solid substance. )

From the analysis result of ¹ H-NMR, the orange solid substance was confirmed to be the compound 3 represented by the following chemical formula (C3).

¹ H-NMR δ [ppm]: 1.70 (s, 3H), 4.16-4.26 (m, 6H), 4.34 (t, 4H), 6.90 (d, 2H), 7 .18-7.22 (m, 6H), 7.45 (d, 4H), 7.53 (d, 4H), 7.71 (d, 4H).

（合成例４）
化合物４（Ｃ４）の合成：［反応式（６）］
４−ヨード安息香酸メチル（１．６ｇ、６．０ｍｍｏｌ）とＴＨＦ（３０ｍＬ）の混合物を−２０℃まで冷却し、イソプロピルマグネシウムクロリド−塩化リチウム錯体のＴＨＦ溶液（約１４質量％、６．２ｍＬ、５．３ｍｍｏｌ）を滴下した。得られた混合物を−２０℃で１時間攪拌した後、臭化銅（Ｉ）−ジメチルスルフィド錯体（１．２ｇ、６．０ｍｍｏｌ）を加えた。得られた混合物を３５℃まで加熱した後、Ｃ_６０フラーレン（０．４８ｇ、０．６７ｍｍｏｌ）のＯＤＣＢ（３５ｍＬ）溶液を加えた。得られた混合物を６０℃で３時間攪拌した後、飽和塩化アンモニウム水溶液（１ｍＬ）を加えた。得られた混合物を濾過した後、ロータリーエバポレーターで濃縮することで、黒色固体状の粗生成物（０．８３ｇ）を得た。シリカゲルカラムクロマトグラフィー（展開溶媒：ヘキサン−酢酸エチル（９：１））で粗生成物を精製することで、赤褐色固体状物質として、化合物４（Ｃ４）（０．２５ｇ、０．１７ｍｍｏｌ、収率２６％）を得た。

(Synthesis Example 4)
Synthesis of Compound 4 (C4): [Reaction Formula (6)]
A mixture of methyl 4-iodobenzoate (1.6 g, 6.0 mmol) and THF (30 mL) was cooled to −20 ° C., and a solution of isopropylmagnesium chloride-lithium chloride complex in THF (about 14% by mass, 6.2 mL, 5.3 mmol) was added dropwise. After the resulting mixture was stirred at −20 ° C. for 1 hour, copper (I) bromide-dimethyl sulfide complex (1.2 g, 6.0 mmol) was added. After the resulting mixture was heated to 35 ° C., a solution of C ₆₀ fullerene (0.48 g, 0.67 mmol) in ODCB (35 mL) was added. The resulting mixture was stirred at 60 ° C. for 3 hours, and a saturated aqueous ammonium chloride solution (1 mL) was added. The obtained mixture was filtered and then concentrated by a rotary evaporator to obtain a black solid crude product (0.83 g). By purifying the crude product by silica gel column chromatography (developing solvent: hexane-ethyl acetate (9: 1)), compound 4 (C4) (0.25 g, 0.17 mmol, yield) was obtained as a reddish brown solid substance. 26%).

From the analysis result of ¹ H-NMR, the reddish brown solid substance was confirmed to be the compound 4 represented by the following chemical formula (C4).

¹ H-NMR δ [ppm]: 3.90 (s, 3H), 3.93 (s, 6H), 3.97 (s, 6H), 5.34 (s, 1H), 7.44 (d 2H), 7.65 (d, 4H), 7.83-7.89 (m, 10H), 8.03 (d, 4H).

（合成例５）
化合物５（Ｃ５）の合成：［反応式（７）］
合成例４で得た化合物４（０．１４ｇ、０．１０ｍｍｏｌ）のＯＤＣＢ（６０ｍＬ）溶液に数平均分子量（Ｍ_ｎ）約２０００のフォンブリンＺｄｏｌ（ソルベイスペシャルティポリマーズ社製、パーフルオロポリエーテル基の平均式量（Ｍｎ）約２０００）（２．１ｇ、１．１ｍｍｏｌ）のＨＦＴＣＢ（６０ｍＬ）溶液を加えた。得られた混合物にトリフルオロメタンスルホン酸（１ｍＬ）を滴下した後、モレキュラーシーブス４Ａが入ったソックスレー抽出器とジムロート冷却管を取り付け、１９０℃に設定した湯浴で加熱し、２時間攪拌しながら還流した。反応混合物を室温まで冷却し、アンモニア水（１０ｍＬ）を加えて中和した後、ロータリーエバポレーターで濃縮した。得られた油状物質を適量のフッ素系溶媒ＡＫ−２２５（旭硝子社製）に溶解させた後、ロータリーエバポレーターで濃縮することで、黒色油状の粗生成物（２．３ｇ）を得た。

(Synthesis Example 5)
Synthesis of Compound 5 (C5): [Reaction Formula (7)]
Fomblin Zdol (manufactured by Solvay Specialty Polymers, perfluoropolyether group) having a number average molecular weight (M _n ) of about 2000 in an ODCB (60 mL) solution of Compound 4 (0.14 g, 0.10 mmol) obtained in Synthesis Example 4 A HFTCB (60 mL) solution of average formula weight (Mn) about 2000) (2.1 g, 1.1 mmol) was added. After trifluoromethanesulfonic acid (1 mL) was added dropwise to the resulting mixture, a Soxhlet extractor containing molecular sieves 4A and a Dimroth condenser were attached, heated in a hot water bath set at 190 ° C., and refluxed with stirring for 2 hours. did. The reaction mixture was cooled to room temperature, neutralized with aqueous ammonia (10 mL), and then concentrated on a rotary evaporator. The obtained oily substance was dissolved in an appropriate amount of a fluorine-based solvent AK-225 (manufactured by Asahi Glass Co., Ltd.) and then concentrated by a rotary evaporator to obtain a black oily crude product (2.3 g).

  Next, the crude product is put into a thick stainless steel container (inner diameter 20 mm × depth 200 mm) having an inlet and an outlet, and the temperature in the container is maintained at 60 ° C., while the supercritical phase chromatography pump PU Using -2086-CO2 (manufactured by JASCO Corporation), supercritical carbon dioxide was fed to the container at a liquefied carbon dioxide equivalent flow rate of 2 mL / min. At this time, the pressure in the container was changed in the range of 9 to 14 MPa to remove impurities such as unreacted fomblin Zdol. Thereafter, the pressure in the container was increased to 27 MPa, and compound 5 (C5) (0.77 g, yield 69%) was extracted as a reddish brown solid substance.

From the analysis result of ¹ H-NMR, the reddish brown solid substance was confirmed to be the compound 5 represented by the following chemical formula (C5).

¹ H-NMR δ [ppm]: 3.97 (br, 10H), 4.74 (br, 10H), 5.44 (brs, 1H), 7.61 (br, 2H), 7.83 (br 4H), 7.94 (br, 2H), 8.01 (br, 8H), 8.17 (br, 4H).

（式中、ｐ及びｑは平均重合度であり、パーフルオロポリエーテル基の平均式量（Ｍｎ）は約２０００であり、Ｒ_ｆ ^２中の（ＣＦ_２Ｏ）と（ＣＦ_２ＣＦ_２Ｏ）との順序は任意である。）
（合成例６）
化合物６（Ｃ６）の合成：［反応式（８）］
合成例５で得た化合物５（０．２０ｇ、１８μｍｏｌ）とトリエチルアミン（３５ｍｇ、０．３５ｍｍｏｌ）とをフッ素系溶媒ＡＫ−２２５（旭硝子社製）（１０ｍＬ）に加えた。得られた混合物を氷浴で冷却した後、塩化ベンゾイル（３２ｍｇ、０．２３ｍｍｏｌ）を加えた。得られた混合物を室温で１７時間攪拌した。反応混合物にアンモニア水（１ｍＬ）を加えた後、ロータリーエバポレーターで濃縮した。得られた赤褐色固体状物質を適量のテトラデカフルオロヘキサンに溶解させた後、ロータリーエバポレーターで濃縮することで、赤褐色固体状の粗生成物（１０１ｍｇ）を得た。

(Wherein p and q are the average degree of polymerization, the average formula weight (Mn) of the perfluoropolyether group is about 2000, and (CF ₂ O) and (CF ₂ CF ₂ O) in R _f ² And the order is arbitrary.)
(Synthesis Example 6)
Synthesis of Compound 6 (C6): [Reaction Formula (8)]
Compound 5 (0.20 g, 18 μmol) obtained in Synthesis Example 5 and triethylamine (35 mg, 0.35 mmol) were added to a fluorine-based solvent AK-225 (Asahi Glass Co., Ltd.) (10 mL). The resulting mixture was cooled in an ice bath and benzoyl chloride (32 mg, 0.23 mmol) was added. The resulting mixture was stirred at room temperature for 17 hours. Aqueous ammonia (1 mL) was added to the reaction mixture, and the mixture was concentrated on a rotary evaporator. The obtained reddish brown solid substance was dissolved in an appropriate amount of tetradecafluorohexane and then concentrated by a rotary evaporator to obtain a reddish brown solid crude product (101 mg).

  Next, the crude product is put into a thick stainless steel container (inner diameter 20 mm × depth 200 mm) having an inlet and an outlet, and the temperature in the container is maintained at 60 ° C., while the supercritical phase chromatography pump PU Using -2086-CO2 (manufactured by JASCO Corporation), supercritical carbon dioxide was fed to the container at a liquefied carbon dioxide equivalent flow rate of 2 mL / min. At this time, the pressure in the container was changed in the range of 9 to 12 MPa to remove impurities. Thereafter, the pressure in the container was increased to 27 MPa, and compound 6 (C6) (51 mg, yield 24%) was extracted as a reddish brown solid substance.

From the analysis result of ¹ H-NMR, it was confirmed that the reddish brown solid substance was Compound 6 represented by the following chemical formula (C6).

¹ H-NMR δ [ppm]: 4.75 (br, 20H), 5.42 (brs, 1H), 7.24 (br, 10H), 7.41 (br, 15H), 7.62 (m 2H), 7.87 (br, 6H), 8.03 (br, 8H), 8.19 (br, 4H).

（式中、ｐ及びｑは平均重合度であり、パーフルオロポリエーテル基の平均式量（Ｍｎ）は約２０００であり、Ｒ_ｆ ^２中の（ＣＦ_２Ｏ）と（ＣＦ_２ＣＦ_２Ｏ）との順序は任意である。）
（合成例７）
化合物７（Ｃ７）の合成：［反応式（９）］
５−ヨードイソフタル酸ジメチル（２．９ｇ、８．９ｍｍｏｌ）とＴＨＦ（５０ｍＬ）の混合物を−２０℃まで冷却し、イソプロピルマグネシウムクロリド−塩化リチウム錯体のＴＨＦ溶液（約１４質量％、８．４ｍＬ、８．１ｍｍｏｌ）を滴下した。得られた混合物を−２０℃で１時間攪拌した後、臭化銅（Ｉ）−ジメチルスルフィド錯体（１．９ｇ、９．１ｍｍｏｌ）を加えた。得られた混合物を３０℃まで加熱した後、Ｃ_６０フラーレン（０．７２ｇ、１．０ｍｍｏｌ）のＯＤＣＢ（５０ｍＬ）溶液を加えた。得られた混合物を６０℃で４時間攪拌した後、飽和塩化アンモニウム水溶液（１ｍＬ）を加えた。得られた混合物を濾過した後、ロータリーエバポレーターにより溶液の体積を減少させた。得られた混合物にメタノールを加えることで、赤褐色固体状物質として、化合物７（Ｃ７）（１．５ｇ、０．９０ｍｍｏｌ、収率９０％）が析出した。

(Wherein p and q are the average degree of polymerization, the average formula weight (Mn) of the perfluoropolyether group is about 2000, and (CF ₂ O) and (CF ₂ CF ₂ O) in R _f ² And the order is arbitrary.)
(Synthesis Example 7)
Synthesis of Compound 7 (C7): [Reaction Formula (9)]
A mixture of dimethyl 5-iodoisophthalate (2.9 g, 8.9 mmol) and THF (50 mL) was cooled to −20 ° C., and a solution of isopropylmagnesium chloride-lithium chloride complex in THF (about 14% by mass, 8.4 mL, 8.1 mmol) was added dropwise. The resulting mixture was stirred at −20 ° C. for 1 hour, and then copper (I) bromide-dimethyl sulfide complex (1.9 g, 9.1 mmol) was added. After the resulting mixture was heated to 30 ° C., a solution of C ₆₀ fullerene (0.72 g, 1.0 mmol) in ODCB (50 mL) was added. The resulting mixture was stirred at 60 ° C. for 4 hours, and then a saturated aqueous ammonium chloride solution (1 mL) was added. After the resulting mixture was filtered, the volume of the solution was reduced by a rotary evaporator. By adding methanol to the obtained mixture, Compound 7 (C7) (1.5 g, 0.90 mmol, yield 90%) was precipitated as a reddish brown solid substance.

From the analysis result of ¹ H-NMR, the reddish brown solid substance was confirmed to be compound 7 represented by the following chemical formula (C7).

¹ H-NMR δ [ppm]: 3.69 (s, 6H), 3.75 (s, 12H), 3.84 (s, 12H), 5.37 (s, 1H), 8.23 (s 2H), 8.36 (s, 4H), 8.52 (s, 4H), 8.60 (s, 1H), 8.63 (s, 2H), 8.72 (s, 2H).

（合成例８）
化合物８（Ｃ８）の合成：［反応式（１０）］
合成例７で得た化合物７（０．１８ｇ、０．１１ｍｍｏｌ）のＯＤＣＢ（６０ｍＬ）溶液に数平均分子量（Ｍ_ｎ）約２０００のフォンブリンＺｄｏｌ（ソルベイスペシャルティポリマーズ社製、パーフルオロポリエーテル基の平均式量（Ｍｎ）約２０００）（４．１ｇ、２．１ｍｍｏｌ）のＨＦＴＣＢ（６０ｍＬ）溶液を加えた。得られた混合物にトリフルオロメタンスルホン酸（１ｍＬ）を滴下した後、モレキュラーシーブス４Ａが入ったソックスレー抽出器とジムロート冷却管を取り付け、１９０℃に設定した湯浴で加熱し、５時間攪拌しながら還流した。反応混合物を室温まで冷却し、アンモニア水（１０ｍＬ）を加えて中和した後、ロータリーエバポレーターで濃縮した。得られた油状物質を適量のフッ素系溶媒ＡＫ−２２５に溶解させた後、ロータリーエバポレーターで濃縮することで、黒色油状の粗生成物（４．２ｇ）を得た。

(Synthesis Example 8)
Synthesis of Compound 8 (C8): [Reaction Formula (10)]
Fomblin Zdol (manufactured by Solvay Specialty Polymers, perfluoropolyether group) having a number average molecular weight (M _n ) of about 2,000 in a ODCB (60 mL) solution of Compound 7 (0.18 g, 0.11 mmol) obtained in Synthesis Example 7 A solution of an average formula weight (Mn) of about 2000) (4.1 g, 2.1 mmol) in HFTCB (60 mL) was added. After trifluoromethanesulfonic acid (1 mL) was added dropwise to the resulting mixture, a Soxhlet extractor containing molecular sieves 4A and a Dimroth condenser were attached, heated in a hot water bath set at 190 ° C., and refluxed with stirring for 5 hours. did. The reaction mixture was cooled to room temperature, neutralized with aqueous ammonia (10 mL), and then concentrated on a rotary evaporator. The obtained oily substance was dissolved in an appropriate amount of a fluorine-based solvent AK-225, and then concentrated by a rotary evaporator to obtain a black oily crude product (4.2 g).

  Next, the crude product is put into a thick stainless steel container (inner diameter 20 mm × depth 200 mm) having an inlet and an outlet, and the temperature in the container is maintained at 60 ° C., while the supercritical phase chromatography pump PU Using -2086-CO2 (manufactured by JASCO Corporation), supercritical carbon dioxide was fed to the container at a liquefied carbon dioxide equivalent flow rate of 2 mL / min. At this time, the pressure in the container was changed in the range of 9 to 15 MPa to remove impurities such as unreacted fomblin Zdol. Thereafter, the pressure in the container was increased to 27 MPa, and compound 8 (C8) (0.84 g, yield 37%) was extracted as a reddish brown solid substance.

From the analysis result of ¹ H-NMR, the reddish brown solid substance was confirmed to be the compound 8 represented by the following chemical formula (C8).

¹ H-NMR δ [ppm]: 3.95 (br, 20H), 4.73 (br, 20H), 5.40 (brs, 1H), 8.22 (brs, 2H), 8.33 (brs) 4H), 8.50 (brs, 4H), 8.61 (br, 3H), 8.73 (brs, 2H).

（式中、ｐ及びｑは平均重合度であり、パーフルオロポリエーテル基の平均式量（Ｍｎ）は約２０００であり、Ｒ_ｆ ^２中の（ＣＦ_２Ｏ）と（ＣＦ_２ＣＦ_２Ｏ）との順序は任意である。）
（合成例９）
化合物９（Ｃ９）の合成：［反応式（１１）］
合成例８で得た化合物８（０．４８ｇ、２２μｍｏｌ）とトリエチルアミン（８２ｍｇ、０．８１ｍｍｏｌ）とをフッ素系溶媒ＡＫ−２２５（１０ｍＬ）に加えた。得られた混合物を氷浴で冷却した後、１−ナフトイルクロリド（８１ｍｇ、０．４２ｍｍｏｌ）加えた。得られた混合物を室温で１７時間攪拌した。反応混合物にアンモニア水（１ｍＬ）を加えた後、ロータリーエバポレーターで濃縮した。得られた赤褐色固体状物質を適量のフッ素系溶媒ＡＫ−２２５に溶解させた後、ロータリーエバポレーターで濃縮することで、赤褐色固体状の粗生成物（４８５ｍｇ）を得た。

(Wherein p and q are the average degree of polymerization, the average formula weight (Mn) of the perfluoropolyether group is about 2000, and (CF ₂ O) and (CF ₂ CF ₂ O) in R _f ² And the order is arbitrary.)
(Synthesis Example 9)
Synthesis of Compound 9 (C9): [Reaction Formula (11)]
Compound 8 (0.48 g, 22 μmol) obtained in Synthesis Example 8 and triethylamine (82 mg, 0.81 mmol) were added to the fluorine-based solvent AK-225 (10 mL). The resulting mixture was cooled in an ice bath and 1-naphthoyl chloride (81 mg, 0.42 mmol) was added. The resulting mixture was stirred at room temperature for 17 hours. Aqueous ammonia (1 mL) was added to the reaction mixture, and the mixture was concentrated on a rotary evaporator. The obtained reddish brown solid substance was dissolved in an appropriate amount of a fluorine-based solvent AK-225 and then concentrated by a rotary evaporator to obtain a reddish brown solid crude product (485 mg).

  Next, the crude product is put into a thick stainless steel container (inner diameter 20 mm × depth 200 mm) having an inlet and an outlet, and the temperature in the container is maintained at 60 ° C., while the supercritical phase chromatography pump PU Using -2086-CO2 (manufactured by JASCO Corporation), supercritical carbon dioxide was fed to the container at a liquefied carbon dioxide equivalent flow rate of 2 mL / min. At this time, the pressure in the container was changed in the range of 9 to 16 MPa to remove impurities. Thereafter, the pressure in the container was increased to 27 MPa, and compound 9 (C9) (405 mg, yield 83%) was extracted as a reddish brown solid substance.

From the analysis result of ¹ H-NMR, the reddish brown solid substance was confirmed to be the compound 9 represented by the following chemical formula (C9).

¹ H-NMR δ [ppm]: 4.77 (br, 40H), 5.53 (brs, 1H), 7.22 (br, 4H), 7.32-7.58 (m, 14H), 7 .75-8.30 (m, 17H), 8.48 (br, 9H), 8.58 (br, 3H), 8.73 (brs, 2H), 8.86 (br, 5H).

（式中、ｐ及びｑは平均重合度であり、パーフルオロポリエーテル基の平均式量（Ｍｎ）は約２０００であり、Ｒ_ｆ ^２中の（ＣＦ_２Ｏ）と（ＣＦ_２ＣＦ_２Ｏ）との順序は任意である。）
（合成例１０）
化合物１０（Ｃ１０）の合成：［反応式（１２）］
４−ヨード安息香酸メチル（０．２６ｇ、０．９８ｍｍｏｌ）とＴＨＦ（１ｍＬ）の混合物を−２０℃まで冷却し、イソプロピルマグネシウムクロリド−塩化リチウム錯体のＴＨＦ溶液（約１４質量％、１．０ｍＬ、０．９０ｍｍｏｌ）を滴下した。得られた混合物を−２０℃で１時間攪拌した後、臭化銅（Ｉ）−ジメチルスルフィド錯体（０．２１ｇ、１．０ｍｍｏｌ）とピリジン（０．７９ｇ、１０ｍｍｏｌ）を加えた。得られた混合物を３０℃まで加熱した後、合成例４で得られた化合物４（４８ｍｇ、３３μｍｏｌ）のＯＤＣＢ（１２ｍＬ）溶液を加えた。得られた混合物を４０℃で６時間攪拌した後、飽和塩化アンモニウム水溶液（１ｍＬ）を加えた。得られた混合物を濾過した後、ロータリーエバポレーターで濃縮することで、赤紫色固体状の粗生成物（０．２７ｇ）を得た。シリカゲルカラムクロマトグラフィー（展開溶媒：ヘキサン−酢酸エチル（２：１））で粗生成物を精製することで、赤褐色固体状物質として、化合物１０（Ｃ１０）（０．２５ｇ、０．１７ｍｍｏｌ、収率２６％）を得た。

(Wherein p and q are the average degree of polymerization, the average formula weight (Mn) of the perfluoropolyether group is about 2000, and (CF ₂ O) and (CF ₂ CF ₂ O) in R _f ² And the order is arbitrary.)
(Synthesis Example 10)
Synthesis of Compound 10 (C10): [Reaction Formula (12)]
A mixture of methyl 4-iodobenzoate (0.26 g, 0.98 mmol) and THF (1 mL) was cooled to −20 ° C., and a solution of isopropylmagnesium chloride-lithium chloride complex in THF (about 14% by mass, 1.0 mL, 0.90 mmol) was added dropwise. After the resulting mixture was stirred at −20 ° C. for 1 hour, copper (I) bromide-dimethylsulfide complex (0.21 g, 1.0 mmol) and pyridine (0.79 g, 10 mmol) were added. After the obtained mixture was heated to 30 ° C., a solution of Compound 4 (48 mg, 33 μmol) obtained in Synthesis Example 4 in ODCB (12 mL) was added. The resulting mixture was stirred at 40 ° C. for 6 hours, and then a saturated aqueous ammonium chloride solution (1 mL) was added. The obtained mixture was filtered and then concentrated by a rotary evaporator to obtain a crude product (0.27 g) as a reddish purple solid. By purifying the crude product by silica gel column chromatography (developing solvent: hexane-ethyl acetate (2: 1)), compound 10 (C10) (0.25 g, 0.17 mmol, yield) was obtained as a reddish brown solid substance. 26%).

From the analysis result of MS, it was confirmed that the compound 10 represented by the following chemical formula (C10) is a fullerene derivative having two partial structures X ¹ from the reddish brown solid substance.

MS: 2072 ([M−H] ⁻ )

（上記Ｘ^１の構造式中、中央の５員環とそれを囲む６員環はフラーレン骨格に属す。）
（合成例１１）
化合物１１（Ｃ１１）の合成：［反応式（１３）］
合成例１０で得た化合物１０（２１ｍｇ、１０μｍｏｌ）のＯＤＣＢ（６０ｍＬ）溶液に数平均分子量（Ｍ_ｎ）約２０００のフォンブリンＺｄｏｌ（ソルベイスペシャルティポリマーズ社製、パーフルオロポリエーテル基の平均式量（Ｍｎ）約２０００）（０．４０ｇ、０．２０ｍｍｏｌ）のＨＦＴＣＢ（６０ｍＬ）溶液を加えた。得られた混合物にトリフルオロメタンスルホン酸（１ｍＬ）を滴下した後、モレキュラーシーブス４Ａが入ったソックスレー抽出器とジムロート冷却管を取り付け、１９０℃に設定した湯浴で加熱し、２時間攪拌しながら還流した。反応混合物を室温まで冷却し、アンモニア水（１０ｍＬ）を加えて中和した後、ロータリーエバポレーターで濃縮した。得られた油状物質を適量のフッ素系溶媒ＡＫ−２２５に溶解させた後、ロータリーエバポレーターで濃縮することで、褐色油状の粗生成物（０．５２ｇ）を得た。

(The structural formula of X ^1, 5-membered ring and 6 Inwa surrounding it in the center belongs to the fullerene skeleton.)
(Synthesis Example 11)
Synthesis of Compound 11 (C11): [Reaction Formula (13)]
Fomblin Zdol (manufactured by Solvay Specialty Polymers, average formula weight of perfluoropolyether group) having a number average molecular weight (M _n ) of about 2000 in an ODCB (60 mL) solution of Compound 10 (21 mg, 10 μmol) obtained in Synthesis Example 10 A solution of about 2000) (0.40 g, 0.20 mmol) in HFTCB (60 mL) was added. After trifluoromethanesulfonic acid (1 mL) was added dropwise to the resulting mixture, a Soxhlet extractor containing molecular sieves 4A and a Dimroth condenser were attached, heated in a hot water bath set at 190 ° C., and refluxed with stirring for 2 hours. did. The reaction mixture was cooled to room temperature, neutralized with aqueous ammonia (10 mL), and then concentrated on a rotary evaporator. The obtained oily substance was dissolved in an appropriate amount of a fluorine-based solvent AK-225 and then concentrated by a rotary evaporator to obtain a brown oily crude product (0.52 g).

  Next, the crude product is put into a thick stainless steel container (inner diameter 20 mm × depth 200 mm) having an inlet and an outlet, and the temperature in the container is maintained at 60 ° C., while the supercritical phase chromatography pump PU Using -2086-CO2 (manufactured by JASCO Corporation), supercritical carbon dioxide was fed to the container at a liquefied carbon dioxide equivalent flow rate of 2 mL / min. At this time, the pressure in the container was changed in the range of 9 to 15 MPa to remove impurities such as unreacted fomblin Zdol. Then, the pressure in the container was raised to 27 MPa, and the compound 11 (30 mg, yield 14%) represented by the following chemical formula (C11) was extracted as a brown solid substance.

From the analysis result of ¹ H-NMR of Synthesis Example 5, the brown solid substance was estimated that Compound 11 (C11) was a fullerene derivative having ^two partial structures X2 below.

（式中、ｐ及びｑは平均重合度であり、パーフルオロポリエーテル基の平均式量（Ｍｎ）は約２０００であり、Ｒ_ｆ ^２中の（ＣＦ_２Ｏ）と（ＣＦ_２ＣＦ_２Ｏ）との順序は任意であり、上記Ｘ^２の構造式中、中央の５員環とそれを囲む６員環はフラーレン骨格に属す。）
（合成例１２）
化合物１２（Ｃ１２）の合成：［反応式（１４）］
合成例１２で得た化合物１２（３０ｍｇ、１．４μｍｏｌ）とトリエチルアミン（４４ｍｇ、０．４３ｍｍｏｌ）とをフッ素系溶媒ＡＫ−２２５（１０ｍＬ）に加えた。得られた混合物を氷浴で冷却した後、１−ナフトイルクロリド（３２ｍｇ、０．１７ｍｍｏｌ）加えた。得られた混合物を室温で１８時間攪拌した。反応混合物にアンモニア水（１ｍＬ）を加えた後、ロータリーエバポレーターで濃縮した。得られた赤褐色固体状物質を適量のテトラデカフルオロヘキサンに溶解させた後、ロータリーエバポレーターで濃縮することで、赤褐色固体状の粗生成物（５２ｍｇ）を得た。

(Wherein p and q are the average degree of polymerization, the average formula weight (Mn) of the perfluoropolyether group is about 2000, and (CF ₂ O) and (CF ₂ CF ₂ O) in R _f ² And in the structural formula of X ² above, the central 5-membered ring and the 6-membered ring surrounding it belong to the fullerene skeleton.)
(Synthesis Example 12)
Synthesis of Compound 12 (C12): [Reaction Formula (14)]
Compound 12 (30 mg, 1.4 μmol) obtained in Synthesis Example 12 and triethylamine (44 mg, 0.43 mmol) were added to a fluorine-based solvent AK-225 (10 mL). The resulting mixture was cooled in an ice bath and 1-naphthoyl chloride (32 mg, 0.17 mmol) was added. The resulting mixture was stirred at room temperature for 18 hours. Aqueous ammonia (1 mL) was added to the reaction mixture, and the mixture was concentrated on a rotary evaporator. The obtained reddish brown solid substance was dissolved in an appropriate amount of tetradecafluorohexane and then concentrated by a rotary evaporator to obtain a reddish brown solid crude product (52 mg).

  Next, the crude product is put into a thick stainless steel container (inner diameter 20 mm × depth 200 mm) having an inlet and an outlet, and the temperature in the container is maintained at 60 ° C., while the supercritical phase chromatography pump PU Using -2086-CO2 (manufactured by JASCO Corporation), supercritical carbon dioxide was fed to the container at a liquefied carbon dioxide equivalent flow rate of 2 mL / min. At this time, the pressure in the container was changed in the range of 9 to 16 MPa to remove impurities. Then, the pressure in the container was increased to 27 MPa, and compound 12 (C12) (12 mg, yield 38%) was extracted as a reddish brown solid substance.

From the analysis result of ¹ H-NMR of Synthesis Example 9, the reddish brown solid substance was estimated that the compound 12 represented by the following chemical formula (C12) was a fullerene derivative having two partial structures X ³ below.

（式中、ｐ及びｑは平均重合度であり、パーフルオロポリエーテル基の平均式量（Ｍｎ）は約２０００であり、Ｒ_ｆ ^２中の（ＣＦ_２Ｏ）と（ＣＦ_２ＣＦ_２Ｏ）との順序は任意であり、上記Ｘ^３の構造式中、中央の５員環とそれを囲む６員環はフラーレン骨格に属す。）
（合成例１３）
化合物１３（Ｃ１３）の合成：［反応式（１５）］
４−ヨード安息香酸メチル（１．２ｇ、４．４ｍｍｏｌ）とＴＨＦ（５ｍＬ）の混合物を−２０℃まで冷却し、イソプロピルマグネシウムクロリド−塩化リチウム錯体のＴＨＦ溶液（約１４質量％、４．７ｍＬ、４．０ｍｍｏｌ）を滴下した。得られた混合物を−２０℃で１時間攪拌した後、臭化銅（Ｉ）−ジメチルスルフィド錯体（０．９１ｇ、４．４ｍｍｏｌ）とピリジン（３．２ｇ、４０ｍｍｏｌ）を加えた。得られた混合物を３０℃まで加熱した後、合成例７で得られた化合物７（０．３４ｇ、０．２０ｍｍｏｌ）のＯＤＣＢ（１０ｍＬ）溶液を加えた。得られた混合物を４０℃で２０時間攪拌した後、飽和塩化アンモニウム水溶液（１ｍＬ）を加えた。得られた混合物を濾過した後、ロータリーエバポレーターで濃縮することで、茶褐色固体状の粗生成物（２．７ｇ）を得た。シリカゲルカラムクロマトグラフィー（展開溶媒：ヘキサン−酢酸エチル（２：１））で粗生成物を精製することで、赤褐色固体状物質として、化合物１３（Ｃ１３）（０．２４ｇ、０．１０ｍｍｏｌ、収率５１％）を得た。

(Wherein p and q are the average degree of polymerization, the average formula weight (Mn) of the perfluoropolyether group is about 2000, and (CF ₂ O) and (CF ₂ CF ₂ O) in R _f ² And in the structural formula of X ³ above, the central 5-membered ring and the 6-membered ring surrounding it belong to the fullerene skeleton.)
(Synthesis Example 13)
Synthesis of Compound 13 (C13): [Reaction Formula (15)]
A mixture of methyl 4-iodobenzoate (1.2 g, 4.4 mmol) and THF (5 mL) was cooled to −20 ° C., and a solution of isopropylmagnesium chloride-lithium chloride complex in THF (about 14% by mass, 4.7 mL, 4.0 mmol) was added dropwise. After the resulting mixture was stirred at −20 ° C. for 1 hour, copper (I) bromide-dimethylsulfide complex (0.91 g, 4.4 mmol) and pyridine (3.2 g, 40 mmol) were added. After the obtained mixture was heated to 30 ° C., a solution of Compound 7 (0.34 g, 0.20 mmol) obtained in Synthesis Example 7 in ODCB (10 mL) was added. The resulting mixture was stirred at 40 ° C. for 20 hours, and then a saturated aqueous ammonium chloride solution (1 mL) was added. The obtained mixture was filtered and then concentrated on a rotary evaporator to obtain a brown solid crude product (2.7 g). By purifying the crude product by silica gel column chromatography (developing solvent: hexane-ethyl acetate (2: 1)), compound 13 (C13) (0.24 g, 0.10 mmol, yield) was obtained as a reddish brown solid substance. 51%).

Red-brown solid material, from analysis of MS, the compound 13 represented by the following chemical formula (C13) was confirmed to be a fullerene derivative having a following partial structure X ¹ and the following partial structure Y ^1.

MS: 2362 ([M−H] ⁻ )

（上記Ｘ^１及びＹ^１の構造式中、中央の５員環とそれを囲む６員環はフラーレン骨格に属す。）
（合成例１４）
化合物１４（Ｃ１４）の合成：［反応式（１６）］
合成例１３で得た化合物１３（０．１１ｇ、４８μｍｏｌ）のＯＤＣＢ（６０ｍＬ）溶液に数平均分子量（Ｍ_ｎ）約２０００のフォンブリンＺｄｏｌ（ソルベイスペシャルティポリマーズ社製、パーフルオロポリエーテル基の平均式量（Ｍｎ）約２０００）（３．１ｇ、１．５ｍｍｏｌ）のＨＦＴＣＢ（６０ｍＬ）溶液を加えた。得られた混合物にトリフルオロメタンスルホン酸（１ｍＬ）を滴下した後、モレキュラーシーブス４Ａが入ったソックスレー抽出器とジムロート冷却管を取り付け、１９０℃に設定した湯浴で加熱し、５時間攪拌しながら還流した。反応混合物を室温まで冷却し、アンモニア水（１０ｍＬ）を加えて中和した後、ロータリーエバポレーターで濃縮した。得られた油状物質を適量のフッ素系溶媒ＡＫ−２２５に溶解させた後、ロータリーエバポレーターで濃縮することで、褐色油状の粗生成物（０．５２ｇ）を得た。

(In the structural formulas of X ¹ and Y ¹ above, the central 5-membered ring and the 6-membered ring surrounding it belong to the fullerene skeleton.)
(Synthesis Example 14)
Synthesis of Compound 14 (C14): [Reaction Formula (16)]
Fomblin Zdol (manufactured by Solvay Specialty Polymers, average formula of perfluoropolyether group) having a number average molecular weight (M _n ) of about 2000 in an ODCB (60 mL) solution of Compound 13 (0.11 g, 48 μmol) obtained in Synthesis Example 13 An amount (Mn) of about 2000) (3.1 g, 1.5 mmol) in HFTCB (60 mL) was added. After trifluoromethanesulfonic acid (1 mL) was added dropwise to the resulting mixture, a Soxhlet extractor containing molecular sieves 4A and a Dimroth condenser were attached, heated in a hot water bath set at 190 ° C., and refluxed with stirring for 5 hours. did. The reaction mixture was cooled to room temperature, neutralized with aqueous ammonia (10 mL), and then concentrated on a rotary evaporator. The obtained oily substance was dissolved in an appropriate amount of a fluorine-based solvent AK-225 and then concentrated by a rotary evaporator to obtain a brown oily crude product (0.52 g).

  Next, the crude product is put into a thick stainless steel container (inner diameter 20 mm × depth 200 mm) having an inlet and an outlet, and the temperature in the container is maintained at 60 ° C., while the supercritical phase chromatography pump PU Using -2086-CO2 (manufactured by JASCO Corporation), supercritical carbon dioxide was fed to the container at a liquefied carbon dioxide equivalent flow rate of 2 mL / min. At this time, the pressure in the container was changed in the range of 9 to 15 MPa to remove impurities such as unreacted fomblin Zdol. Thereafter, the pressure in the container was increased to 27 MPa, and Compound 14 (C14) (0.19 g, yield 13%) was extracted as a brown oily substance.

From the result of ¹ H-NMR analysis of Synthesis Example 5, the brown oily substance was estimated that the compound 14 represented by the following chemical formula (C14) was a fullerene derivative having the following partial structure X ² and the following partial structure Y ² .

（式中、ｐ及びｑは平均重合度であり、パーフルオロポリエーテル基の平均式量（Ｍｎ）は約２０００であり、Ｒ_ｆ ^２中の（ＣＦ_２Ｏ）と（ＣＦ_２ＣＦ_２Ｏ）との順序は任意であり、上記Ｘ^２及びＹ^２の構造式中、中央の５員環とそれを囲む６員環はフラーレン骨格に属す。）
（合成例１５）
化合物１５（Ｃ１５）の合成：［反応式（１７）］
合成例１４で得た化合物１４（０．１９ｇ、６．０μｍｏｌ）とトリエチルアミン（６０ｍｇ、０．５９ｍｍｏｌ）とをフッ素系溶媒ＡＫ−２２５（１０ｍＬ）に加えた。得られた混合物を氷浴で冷却した後、１−ナフトイルクロリド（６４ｍｇ、０．３４ｍｍｏｌ）加えた。得られた混合物を室温で１８時間攪拌した。反応混合物にアンモニア水（１ｍＬ）を加えた後、ロータリーエバポレーターで濃縮した。得られた赤褐色固体状物質を適量のテトラデカフルオロヘキサンに溶解させた後、ロータリーエバポレーターで濃縮することで、赤褐色油状の粗生成物（０．２５ｇ）を得た。

(Wherein p and q are the average degree of polymerization, the average formula weight (Mn) of the perfluoropolyether group is about 2000, and (CF ₂ O) and (CF ₂ CF ₂ O) in R _f ² And in the structural formulas of X ² and Y ² above, the central 5-membered ring and the 6-membered ring surrounding it belong to the fullerene skeleton.)
(Synthesis Example 15)
Synthesis of Compound 15 (C15): [Reaction Formula (17)]
Compound 14 (0.19 g, 6.0 μmol) obtained in Synthesis Example 14 and triethylamine (60 mg, 0.59 mmol) were added to the fluorinated solvent AK-225 (10 mL). The resulting mixture was cooled in an ice bath and 1-naphthoyl chloride (64 mg, 0.34 mmol) was added. The resulting mixture was stirred at room temperature for 18 hours. Aqueous ammonia (1 mL) was added to the reaction mixture, and the mixture was concentrated on a rotary evaporator. The obtained reddish brown solid substance was dissolved in an appropriate amount of tetradecafluorohexane and then concentrated by a rotary evaporator to obtain a reddish brown crude product (0.25 g).

  Next, the crude product is put into a thick stainless steel container (inner diameter 20 mm × depth 200 mm) having an inlet and an outlet, and the temperature in the container is maintained at 60 ° C., while the supercritical phase chromatography pump PU Using -2086-CO2 (manufactured by JASCO Corporation), supercritical carbon dioxide was fed to the container at a liquefied carbon dioxide equivalent flow rate of 2 mL / min. At this time, the pressure in the container was changed in the range of 9 to 16 MPa to remove impurities. Thereafter, the pressure in the container was increased to 27 MPa, and Compound 15 (C15) (0.17 mg, yield 84%) was extracted as a reddish brown oily substance.

From the analysis result of ¹ H-NMR of Synthesis Example 9, the reddish brown oily substance was estimated that the compound 15 represented by the following chemical formula (C15) was a fullerene derivative having the following partial structure X ³ and the following partial structure Y ³ .

（式中、ｐ及びｑは平均重合度であり、パーフルオロポリエーテル基の平均式量（Ｍｎ）は約２０００であり、Ｒ_ｆ ^２中の（ＣＦ_２Ｏ）と（ＣＦ_２ＣＦ_２Ｏ）との順序は任意であり、上記Ｘ^３及びＹ^３の構造式中、中央の５員環とそれを囲む６員環はフラーレン骨格に属す。）
（実施例２）
Ａｒガス雰囲気中で、カーボンをターゲットとして用いた高周波マグネトロンスパッタにより、磁気ディスク用２．５インチガラスプランク上にＤＬＣ（Ｄｉａｍｏｎｄ−Ｌｉｋｅ Ｃａｒｂｏｎ）からなる保護膜を成膜し、模擬ディスクを作製した。

(Wherein p and q are the average degree of polymerization, the average formula weight (Mn) of the perfluoropolyether group is about 2000, and (CF ₂ O) and (CF ₂ CF ₂ O) in R _f ² And in the structural formulas of X ³ and Y ³ above, the central 5-membered ring and the 6-membered ring surrounding it belong to the fullerene skeleton.)
(Example 2)
A protective disk made of DLC (Diamond-Like Carbon) was formed on a 2.5-inch glass plank for a magnetic disk by high-frequency magnetron sputtering using carbon as a target in an Ar gas atmosphere to produce a simulated disk.

  Next, Compound 3 (C3) was dissolved in tetradecafluorohexane to prepare a 0.001 mass% lubricant solution.

  Next, using the dipping method, a lubricant solution was applied to the surface of the protective film of the simulated disk by the following method. That is, after immersing the simulated disk for 30 seconds in the lubricant solution placed in the immersion tank of the dip coater, the lubricant solution is applied to the surface of the protective film of the simulated disk by lifting the simulated disk from the immersion tank. did. Thereafter, the lubricant solution applied to the surface of the protective film of the simulated disk was dried to form a lubricant layer.

(Examples 3 to 6)
Protecting the simulated disk in the same manner as in Example 2 except that Compound 6 (C6), Compound 9 (C9), Compound 12 (C12), and Compound 15 (C15) were used instead of Compound 3 (C3). A lubricant layer was formed on the surface of the film.

(Comparative Example 1)
Instead of compound 3 (C3), the chemical formula

（式中、ｐ及びｑは平均重合度であり、パーフルオロポリエーテル基の平均式量（Ｍｎ）は約２０００であり、Ｒ_ｆ ^２中の（ＣＦ_２Ｏ）と（ＣＦ_２ＣＦ_２Ｏ）との順序は任意である。）
で表される化合物１６（Ｃ１６）を用いた以外は、実施例２と同様にして、模擬ディスクの保護膜の表面に潤滑剤層を形成しようとしたところ、化合物１６がテトラデカフルオロヘキサンに溶解しなかった。

(Wherein p and q are the average degree of polymerization, the average formula weight (Mn) of the perfluoropolyether group is about 2000, and (CF ₂ O) and (CF ₂ CF ₂ O) in R _f ² And the order is arbitrary.)
In the same manner as in Example 2 except that the compound 16 represented by the formula (C16) was used, a lubricant layer was formed on the surface of the protective film of the simulated disk, and the compound 16 was dissolved in tetradecafluorohexane. I did not.

  Compound 16 (C16) is a compound described in Patent Document 2 (Japanese Patent No. 5600202).

(Comparative Example 2)
Instead of tetradecafluorohexane, Bertrell (registered trademark) XF (1,1,1,2,3,4,4,5,5,5-decafluoropentane) (manufactured by Mitsui DuPont Fluorochemicals) was used. Except for the above, a lubricant layer was formed on the surface of the protective film of the simulated disk in the same manner as in Comparative Example 1.

(Comparative Example 3)
Instead of compound 3 (C3), the chemical formula

（式中、ｐ及びｑは平均重合度であり、パーフルオロポリエーテル基の平均式量（Ｍｎ）は約１３００であり、Ｒ_ｆ ^３中の（ＣＦ_２Ｏ）と（ＣＦ_２ＣＦ_２Ｏ）との順序は任意である。）
で表される化合物１７（Ｃ１７）を用いた以外は、実施例２と同様にして、模擬ディスクの保護膜の表面に潤滑剤層を形成した。

(Wherein p and q are the average degree of polymerization, the average formula weight (Mn) of the perfluoropolyether group is about 1300, (CF ₂ O) and (CF ₂ CF ₂ O) in R _f ³ And the order is arbitrary.)
A lubricant layer was formed on the surface of the protective film of the simulated disk in the same manner as in Example 2 except that the compound 17 (C17) represented by the following formula was used.

  Compound 17 (C17) is a compound described in Patent Document 5 (International Publication No. 2017/006812).

(Comparative Example 4)
Instead of compound 3 (C3), the chemical formula

で表される化合物１８（Ｃ１８）を用いた以外は、実施例２と同様にして、模擬ディスクの保護膜の表面に潤滑剤層を形成した。

A lubricant layer was formed on the surface of the protective film of the simulated disk in the same manner as in Example 2 except that the compound 18 represented by (C18) was used.

  Compound 18 (C18) is a compound described in Patent Document 6 (Japanese Patent Laid-Open No. 2017-14192).

  Next, the average film thickness and the bond ratio of the lubricant layer were evaluated.

(Average film thickness of lubricant layer)
Using a Fourier transform infrared spectrometer, Nicolet iS50 (manufactured by Thermo Fisher Scientific), the intensity of the absorption peak corresponding to the stretching vibration energy of the CF bond in the infrared absorption spectrum is measured by a highly sensitive reflection method, and lubrication is performed. The average film thickness of the agent layer was determined. At this time, the film thickness of the lubricant layer was measured four points at a time, and the average value was taken as the average film thickness.

(Lubricant bond bond ratio)
A simulated disk having a lubricant layer formed in Vertrel (registered trademark) XF (1,1,1,2,3,4,4,5,5,5-decafluoropentane) (manufactured by Mitsui DuPont Fluorochemical Co., Ltd.) Was immersed for 10 minutes, and then the simulated disk was lifted to wash away the lubricant not adsorbed on the protective film of the simulated disk. Thereafter, the surface of the simulated disk was dried.

  The ratio of the average film thickness of the lubricant layer before and after the above treatment was taken as the bond ratio.

  Table 1 shows the evaluation results of the average film thickness and the bond ratio of the lubricant layer.

表１から、実施例２〜６で用いられた化合物３、６、９、１２、１５は、比較例２〜４で用いられた化合物１６〜１８に対し、ボンディドレシオが高い強固な潤滑剤層を形成できることがわかる。

From Table 1, compounds 3, 6, 9, 12, and 15 used in Examples 2 to 6 are strong lubricants having a high bond ratio relative to compounds 16 to 18 used in Comparative Examples 2 to 4. It can be seen that a layer can be formed.

  The fullerene derivative of this embodiment is effective for forming a strong lubricant layer having a high bond ratio.

Claims (13)

General formula

(In the formula, FLN is a fullerene skeleton, and A is a general formula A ₁ —CH ₂ —O— (A)
(In the formula, A ₁ is a monovalent perfluoropolyether group.)
Or a group represented by the general formula Ar—COO—CH ₂ —A ₂ —CH ₂ —OCO— (B)
(In the formula, Ar is an aryl group or an aralkyl group, and A ₂ is a divalent perfluoropolyether group.)
R is a hydrogen atom or a methyl group, k is an integer of 5 to 10, m is an integer of 0 to 2, and n is an integer of 1 to 5. )
The fullerene derivative which is a compound represented by these. The fullerene derivative according to claim 1, wherein the fullerene skeleton is C ₆₀ . The fullerene derivative according to claim _1, wherein the perfluoropolyether group of A ₁ and A ₂ has 5 to 100 carbon atoms. The perfluoropolyether groups of A ₁ and A ₂ are represented by the general formula — (CF ₂ ) _x O— (C)
(In the formula, x is an integer of 1 to 5.)
The fullerene derivative as described in any one of Claims 1-3 containing group represented by these. 5. The fullerene derivative according to claim 4, wherein the perfluoropolyether group of A ₁ and A ₂ includes 1 to 50 groups represented by the general formula (C) in which x is 1 or 2. 6. Fullerene derivatives according to any one of the claims 1-5 average formula weight of the perfluoropolyether group _{A 1} and _{A 2} is in the range of 250 to 6,000. The fullerene derivative according to claim 1, wherein the perfluoropolyether groups of A ₁ and A ₂ are linear.   The fullerene derivative according to claim 1, wherein k is 5 or 10. Chemical formula

(In the formula, A ₁ is a monovalent perfluoropolyether group.)
A compound represented by the chemical formula

(In the formula, A ₂ is a divalent perfluoropolyether group.)
A compound represented by the chemical formula

(In the formula, A ₂ is a divalent perfluoropolyether group.)
A compound represented by the chemical formula

(In the formula, A ₂ is a divalent perfluoropolyether group.)
Or a chemical formula represented by

(In the formula, A ₂ is a divalent perfluoropolyether group.)
The fullerene derivative according to claim 1, wherein the fullerene derivative is a compound represented by the formula:   The lubricant containing the fullerene derivative as described in any one of Claims 1-9.   The lubricant according to claim 10, further comprising a perfluoropolyether compound having no fullerene skeleton. General formula

(In the formula, FLN is a fullerene skeleton, A ₂ is a divalent perfluoropolyether group, R is a hydrogen atom or a methyl group, k is an integer of 5 to 10, and m is 0 to 0. 2 is an integer, and n is an integer of 1 to 5.)
The fullerene derivative which is a compound represented by these. Chemical formula

(In the formula, A ₂ is a divalent perfluoropolyether group.)
A compound represented by the chemical formula

(In the formula, A ₂ is a divalent perfluoropolyether group.)
A compound represented by the chemical formula

(In the formula, A ₂ is a divalent perfluoropolyether group.)
Or a chemical formula represented by

(In the formula, A ₂ is a divalent perfluoropolyether group.)
The fullerene derivative according to claim 12, which is a compound represented by the formula: