Organic electroluminescent device

1. An organic electroluminescent device comprising:

a pair of electrodes; and

a layer that is disposed between the pair of electrodes and comprises a compound represented by the following formula (1):

wherein A 1 and A 2 each independently represent an aromatic ring and may be substituents at any of positions 2, 3, 4 and 5 of the thiophene ring; B represents a substituent having a positive Hammett substituent constant σp; C represents a substituent having a negative Hammett substituent constant σp; n1 and n2 each independently represent 0, 1 or 2, wherein n1 and n2 are not 0 at the same time; and the thiophene ring may have a substituent selected from the group consisting of an alkyl group having 1 to 8 carbon atoms, an alkoxy group and a halogen atom.

2. The organic electroluminescent device of claim 1 , wherein the compound represented by formula (1) is a compound represented by the following formula (2):

wherein A 1 and A 2 each independently represent an aromatic ring;

B represents a substituent having a positive Hammett substituent constant σp; R 1 and R 2 each independently represent an alkyl group; n1 and n2 each independently represent 0, 1 or 2, wherein n1 and n2 are not 0 at the same time; and the thiophene ring may have a substituent selected from the group consisting of an alkyl group having 1 to 8 carbon atoms, an alkoxy group and a halogen atom.

3. The organic electroluminescent device of claim 1 , wherein the compound represented by formula (1) exhibits liquid crystallinity.

4. The organic electroluminescent device of claim 2 , wherein the compound represented by formula (2) exhibits liquid crystallinity.

5. The organic electroluminescent device of claim 1 , further comprising a heater that heats the organic electroluminescent device.

6. The organic electroluminescent device of claim 2 , further comprising a heater that heats the organic electroluminescent device.

7. The organic electroluminescent device of claim 3 , further comprising a heater that heats the organic electroluminescent device.

8. The organic electroluminescent device of claim 4 , further comprising a heater that heats the organic electroluminescent device.

9. The organic electroluminescent device of claim 1 , wherein either one of A 1 and A 2 is an aromatic ring having 5 to 10 carbon atoms.

10. The organic electroluminescent device of claim 1 , wherein either one of A 1 and A 2 is one selected from the group consisting of 1,4-phenylene, thiophene-2,5-diyl, 2,6-naphthalene, thiazole-2,5-diyl, pyridine-2,3-diyl, benzofuran-2,5-diyl, benzofuran-2,6-diyl, benzothiophene-2,5-diyl, benzothiophene-2,6-diyl, pyrimidine-2,5-diyl, pyrazine-2,5-diyl and pyridazine-3,6-diyl.

11. The organic electroluminescent device of claim 1 , wherein A 1 is a substituent at position 2 or 5 of the thiophene ring, and A 2 is a substituent at position 5 or 2 of the thiophene ring.

12. The organic electroluminescent device of claim 1 , wherein C represents a substituted amino group or an alkoxy group.

13. The organic electroluminescent device of claim 1 , wherein B represents one selected from the group consisting of an ester group (—COOR 3 ), a sulfonyl group (—SO 2 R 3 ), a sulfoxy group (—SO 3 R 3 ), and the following substituents:

wherein R 3 represents an alkyl group having 1 to 16 carbon atoms.

14. The organic electroluminescent device of claim 2 , wherein R 1 and R 2 are each independently a straight-chain alkyl group.

15. The organic electroluminescent device of claim 2 , wherein R 1 and R 2 are each independently a straight-chain alkyl group having 1 to 6 carbon atoms.

16. The organic electroluminescent device of claim 3 , wherein the compound represented by formula (1) exhibits a smectic or nematic phase.

17. The organic electroluminescent device of claim 4 , wherein the compound represented by formula (2) exhibits a smectic or nematic phase.

18. The organic electroluminescent device of claim 1 , further comprising a hole-transporting layer and an electron-transporting layer.