Asymmetric pyrene derivative and organic electroluminescence device employing the same

1. An asymmetric pyrene derivative represented by formula (2):

wherein, Ar and Ar′ each represents a substituted or unsubstituted aromatic group exclusive of a pyrenyl group, and each of Ar and Ar′ is an aromatic group selected from the group consisting of phenyl group, 1-naphthyl group, 2-naphthyl group, 1-anthryl group, 2-anthryl group, 9-anthryl group, 9-(10-phenyl)anthryl group, 9-(10-naphthyl-1-yl)anthryl group, 9-(10-naphthyl-2-yl)anthryl group, 1-phenanthryl group, 2-phenanthryl group, 3-phenanthryl group, 4-phenanthryl group, 9-phenanthryl group, 1-naphthacenyl group, 2-naphthacenyl group, 9-naphthacenyl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, p-terphenyl-4-yl group, p-terphenyl-3-yl group, p-terphenyl-2-yl group, m-terphenyl-4-yl group, m-terphenyl-3-yl group, m-terphenyl-2-yl group, o-tolyl group, m-tolyl group, p-tolyl group, p-t-butylphenyl group, 3-methyl-2-naphthyl group, 4-methyl-1-naphthyl group, 4-methyl-1-anthryl group,

L and L′ each represents a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthalenylene group, a substituted or unsubstituted fluorenylene group, or a substituted or unsubstituted dibenzosilolylene group;

m represents an integer of 0 to 2;

s represents an integer of 0 to 2; and

L′ or Ar′ bonds to any one of 2 to 10 positions of pyrene;

(3′) Ar=Ar′, L=L′, m=s, t=1, and both L and L′ or pyrene each bonds respectively to different positions of Ar and Ar′, or

(4′) Ar=Ar′, L=L′, m=s, t=1, and both L and L′ or pyrene each bonds to the same positions of Ar and Ar′, excluding a case where L′ or Ar′ bonds to 6 position of pyrene,

provided that symmetric pyrene derivatives are excluded.

2. The asymmetric pyrene derivative according to claim 1 , which is a light emitting material suitable for an organic electroluminescence device.

3. The asymmetric pyrene derivative according to claim 1 , which is a host material suitable for an organic electroluminescence device.

4. An organic electroluminescence device which comprises at least one organic thin film layer including a light emitting layer sandwiched between a pair of electrodes consisting of an anode and a cathode, wherein the organic thin film layer comprises the asymmetric pyrene derivative according to claim 1 .

5. The organic electroluminescence device according to claim 4 , wherein the light emitting layer comprises the asymmetric pyrene derivative as a host material.

6. The organic electroluminescence device according to claim 4 , wherein the light emitting layer further comprises an arylamine compound.

7. The organic electroluminescence device according to claim 4 , wherein the light emitting layer further comprises a styrylamine compound.

8. An asymmetric pyrene derivative represented by formula (2):

wherein, Ar and Ar′ each represents a substituted or unsubstituted aromatic group exclusive of a pyrenyl group, and each of Ar and Ar′ is an aromatic group selected from the group consisting of phenyl group, 1-naphthyl group, 2-naphthyl group, 1-anthryl group, 2-anthryl group, 9-anthryl group, 9-(10-phenyl)anthryl group, 9-(10-naphthyl-1-yl)anthryl group, 9-(10-naphthyl-2-yl)anthryl group, 1-phenanthryl group, 2-phenanthryl group, 3-phenanthryl group, 4-phenanthryl group, 9-phenanthryl group, 1-naphthacenyl group, 2-naphthacenyl group, 9-naphthacenyl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, p-terphenyl-4-yl group, p-terphenyl-3-yl group, p-terphenyl-2-yl group, m-terphenyl-4-yl group, m-terphenyl-3-yl group, m-terphenyl-2-yl group, o-tolyl group, m-tolyl group, p-tolyl group, p-t-butylphenyl group, 3-methyl-2-naphthyl group, 4-methyl-1-naphthyl group, 4-methyl-1-anthryl group,

L and L′ each represents a substituted or unsubstituted naphthalenylene group, a substituted or unsubstituted fluorenylene group, or a substituted or unsubstituted dibenzosilolylene group;

m represents an integer of 0 to 2;

s represents an integer of 0 to 2;

t represents an integer of 0 to 4; and

L′ or Ar′ bonds to any one of 2 to 10 positions of pyrene;

provided that when t is an odd number, Ar, Ar′, L, and L′ satisfy the following requirement (1′), (2′), (3′) or (4′):

(1′) Ar≠Ar′ and/or L≠L′ (wherein ≠ means that each group has a different structure),

(2′) Ar=Ar′, L=L′, and m≠s and/or t≠1,

(3′) Ar=Ar′, L=L′, m=s, t=1, and both L and L′ or pyrene each bonds respectively to different positions of Ar and Ar′, or

(4′) Ar=Ar′, L=L′, m=s, t=1, and both L and L′ or pyrene each bonds to the same positions of Ar and Ar′, excluding a case where L′ or Ar′ bonds to 6 position of pyrene, and

provided that when t=0, then m=0 and Ar is 9-(10-naphthyl-2-yl)anthryl group, or m is 1 or 2, L is:

and Ar is the aromatic group selected from the groups defined above; provided that symmetric pyrene derivatives are excluded.

9. The asymmetric pyrene derivative according to claim 8 , which is a light emitting material suitable for an organic electroluminescence device.

10. The asymmetric pyrene derivative according to claim 8 , which is a host material suitable for an organic electroluminescence device.

11. An organic electroluminescence device which comprises at least one organic thin film layer including a light emitting layer sandwiched between a pair of electrodes consisting of an anode and a cathode, wherein the organic thin film layer comprises the asymmetric pyrene derivative according to claim 8 .

12. The organic electroluminescence device according to claim 11 , wherein the light emitting layer comprises the asymmetric pyrene derivative as a host material.

13. The organic electroluminescence device according to claim 11 , wherein the light emitting layer further comprises an arylamine compound.

14. The organic electroluminescence device according to claim 11 , wherein the light emitting layer further comprises a styrylamine compound.

15. An asymmetric pyrene derivative represented by formula (2):

wherein, Ar and Ar′ each represents a substituted or unsubstituted aromatic group exclusive of a pyrenyl group, and each of Ar and Ar′ is an aromatic group selected from the group consisting of phenyl group, 1-naphthyl group, 2-naphthyl group, 1-anthryl group, 2-anthryl group, 9-anthryl group, 9-(10-phenyl)anthryl group, 9-(10-naphthyl-1-yl)anthryl group, 9-(10-naphthyl-2-yl)anthryl group, 1-phenanthryl group, 2-phenanthryl group, 3-phenanthryl group, 4-phenanthryl group, 9-phenanthryl group, 1-naphthacenyl group, 2-naphthacenyl group, 9-naphthacenyl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, p-terphenyl-4-yl group, p-terphenyl-3-yl group, p-terphenyl-2-yl group, m-terphenyl-4-yl group, m-terphenyl-3-yl group, m-terphenyl-2-yl group, o-tolyl group, m-tolyl group, p-tolyl group, p-t-butylphenyl group, 3-methyl-2-naphthyl group, 4-methyl-1-naphthyl group, 4-methyl-1-anthryl group,

L and L′ each represents a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthalenylene group, a substituted or unsubstituted fluorenylene group, or a substituted or unsubstituted dibenzosilolylene group;

m represents an integer of 0 to 2;

s represents an integer of 0 to 2;

t represents 1, 2, 3, or 4; and

L′ or Ar′ bonds to any one of 2 to 10 positions of pyrene;

provided that when t is an odd number, Ar, Ar′, L and L′ satisfy the following requirement (1′), (2′), (3′) or (4′):

(1′) Ar≠Ar′ and/or L≠L′ (wherein ≠ means that each group has a different structure),

(2′) Ar=Ar′, L=L′, and m≠s and/or t≠1,

(3′) Ar=Ar′, L=L′, m=s, t=1, and both L and L′ or pyrene each bonds respectively to different positions of Ar and Ar′, or

(4′) Ar=Ar′, L=L′, m=s, t=1, and both L and L′ or pyrene each bonds to the same positions of Ar and Ar′, excluding a case where L′ or Ar′ bonds to 6 position of pyrene; and

provided that symmetric pyrene derivatives are excluded.

16. The asymmetric pyrene derivative according to claim 15 , which is a light emitting material suitable for an organic electroluminescence device.

17. The asymmetric pyrene derivative according to claim 15 , which is a host material suitable for an organic electroluminescence device.

18. An organic electroluminescence device which comprises at least one organic thin film layer including a light emitting layer sandwiched between a pair of electrodes consisting of an anode and a cathode, wherein the organic thin film layer comprises the asymmetric pyrene derivative according to claim 15 .

19. The organic electroluminescence device according to claim 18 , wherein the light emitting layer comprises the asymmetric pyrene derivative as a host material.

20. The organic electroluminescence device according to claim 18 , wherein the light emitting layer further comprises an arylamine compound.

21. The organic electroluminescence device according to claim 18 , wherein the light emitting layer further comprises a styrylamine compound.