Fullerene derivative and lubricant

1. A fullerene derivative represented by general formula (1)

(wherein FLN is a fullerene backbone; each A is independently a monovalent group including a divalent perfluoropolyether group; each R is independently a hydrogen atom, a hydrocarbon group, or an alkoxycarbonyl group including a divalent perfluoropolyether group; at least one R from among the 2m R is a hydrocarbon group or an alkoxycarbonyl group including a divalent perfluoropolyether group; m is an integer from 1 to 5; and n is an integer from 1 to 6).

2. The fullerene derivative according to claim 1 , wherein the fullerene backbone is a C 60 backbone.

3. The fullerene derivative according to claim 1 , wherein

at least one R that is bonded to a carbon atom at an α-position of a carbonyl group, from among the 2m R, is a hydrocarbon group or an alkoxycarbonyl group including a divalent perfluoropolyether group.

4. The fullerene derivative according to claim 1 , wherein

the divalent perfluoropolyether group has at least one partial structure selected from partial structures represented by general formula

—(CF 2 ) x O—

(wherein x is an integer from 1 to 5).

5. The fullerene derivative according to claim 4 , wherein

the divalent perfluoropolyether group has a partial structure represented by general formula

—(CF 2 CF 2 O) y (CF 2 O) z —

(wherein each of y and z is independently an integer from 1 to 50).

6. The fullerene derivative according to claim 1 , wherein the divalent perfluoropolyether group is a straight chain.

7. The fullerene derivative according to claim 1 , wherein at least one of the two A and the 2m R includes a non-binding end group that is an aryl group.

8. The fullerene derivative according to claim 7 , wherein the two A have non-binding end groups that are aryl groups.

9. The fullerene derivative according to claim 1 , wherein

m is greater than or equal to 2; and

at least one R that is bonded to a carbon atom at a β-position of a carbonyl group, from among the 2m R, is an alkoxycarbonyl group including a divalent perfluoropolyether group.

10. The fullerene derivative according to claim 1 that is represented by general formula (2)

(wherein R f 1 is a divalent perfluoropolyether group having both ends bonded to methylene groups; and n is 2 or 3).

11. The fullerene derivative according to claim 1 that is represented by general formula (3)

(wherein R f 1 is a divalent perfluoropolyether group having both ends bonded to methylene groups; and n is from 4 to 6).

12. The fullerene derivative according to claim 1 that is represented by general formula (4)

(wherein R f 1 is a divalent perfluoropolyether group having both ends bonded to methylene groups).

13. A lubricant including the fullerene derivative according to claim 1 .

14. The fullerene derivative according to claim 1 , wherein the fullerene derivative is synthesized from an intermediate compound represented by general formula (5)

(wherein FLN is a fullerene backbone; each R 1 is independently a methyl group or an ethyl group; each R is independently a hydrogen atom, a hydrocarbon group, or an alkoxycarbonyl group including a divalent perfluoropolyether group; at least one R from among the 2m R is a hydrocarbon group or an alkoxycarbonyl group including a divalent perfluoropolyether group; m is an integer from 1 to 5; and n is an integer from 1 to 6).

15. A fullerene derivative represented by general formula (5)

(wherein FLN is a fullerene backbone; each R 1 is independently a methyl group or an ethyl group; each R is independently a hydrogen atom, a hydrocarbon group, or an alkoxycarbonyl group including a divalent perfluoropolyether group; at least one R from among the 2m R is a hydrocarbon group or an alkoxycarbonyl group including a divalent perfluoropolyether group; m is an integer from 1 to 5; and n is an integer from 1 to 6).