Organic element for electroluminescent devices

1. An electroluminescent device comprising a light emitting layer comprising a boron complex wherein the boron is bonded to a nitrogen atom of a 6-membered heteroaromatic ring group and to a nitrogen atom of a 5-membered heteroaromatic ring group, provided that the 5- and 6-membered heteroaromatic ring groups are further connected by a methene bridge to form a 6-membered ring, and provided further that the 5-membered heteroaromatic ring contains at least one additional heteroatom that is divalent or trivalent.

2. The device of claim 1 , wherein the additional heteroatom is a N, O, S, Se, or Te atom.

3. The device of claim 1 , wherein the additional heteroatom is a N, O or S atom.

4. The device of claim 1 , wherein the five-membered ring is fused to an additional aromatic ring group.

5. The device of claim 1 , wherein the five-membered ring is fused to an additional aromatic ring group and the six-membered ring is fused to an additional aromatic ring group.

6. The device of claim 1 , wherein the methene bridge is substituted with cyano substituent, an aryl group, a heteroaryl group, or an alkyl group.

7. The device of claim 1 , wherein the boron complex is represented by Formula (1),

wherein:

Ar 1 represents the atoms necessary to form a six-membered heteroaromatic ring;

Ar 2 represents the atoms necessary to form a five-membered heteroaromatic ring that contains at least one additional heteroatom that is divalent or trivalent;

L 1 and L 2 represent independently selected substituents;

Y represents hydrogen or a substituent.

8. The device of claim 7 , wherein, Ar 1 represents the atoms necessary to form pyridine ring group.

9. The device of claim 7 , wherein, Ar 2 represents the atoms necessary to form an imidazole ring group, an oxazole ring group, a thiazole ring group, or a selenazole ring group.

10. The device of claim 7 , wherein Y represents a cyano substituent, a trifluoromethyl substituent, an aryl group, a heteroaryl group, or an alkyl group.

11. The device of claim 7 , wherein L 1 and L 2 represent fluoro substituents.

12. The device of claim 1 , wherein the boron complex is represented by Formula (2),

wherein:

W represents O, S, Se, or N-R a , wherein R a is a substituent;

V 1 and V 2 independently represent hydrogen or an independently selected substituent, provided that V 1 and V 2 may join together to form a ring group;

Ar 1 represents the atoms necessary to form a six-membered heteroaromatic ring group;

L 1 and L 2 represent independently selected substituents;

Y represents hydrogen or a substituent.

13. The device of claim 12 , wherein V 1 and V 2 independently represent an aryl group or an alkyl group.

14. The device of claim 12 , wherein V 1 and V 2 join together to form an aromatic ring group.

15. The device of claim 1 , wherein the boron complex is represented by Formula (3),

wherein:

W represents O, S, Se, or N-R a , wherein R a is a substituent;

V 3 -V 10 independently represent hydrogen or an independently selected substituent, provided that adjacent substituents may join together to form a ring group;

L 1 and L 2 represent independently selected substituents;

Y represents hydrogen or a substituent.

16. The device of claim 15 , wherein W represents S.

17. The device of claim 15 , wherein L 1 and L 2 represent fluoro substituents.

18. The device of claim 15 , wherein, independently, at least two of V 3 -V 6 and at least two of V 7 -V 10 combine to form independently selected ring groups.

19. The device of claim 1 wherein the layer comprises a host and dopant where the dopant is present in an amount of up to 10 wt % of the host.

20. The device of claim 1 wherein the host material is represented by Formula (4),

wherein:

W 1 -W 10 independently represent hydrogen or an independently selected substituent, provided that two adjacent substituents can combine to form rings.

21. The device of claim 20 wherein W 9 and W 10 independently represent naphthyl groups.

22. The device of claim 20 wherein W 9 and W 10 represent a naphthyl group and a biphenyl group.

23. The device of claim 20 wherein W 9 represents a biphenyl group.

24. The device of claim 1 wherein the boron complex is between 0.5 and 8% by volume of the light-emitting layer.

25. A display comprising the electroluminescent device of claim 1 .

26. The device of claim 1 wherein white light is produced either directly or by using filters.

27. An area lighting device comprising the electroluminescent device of claim 1 .

28. A process for emitting light comprising applying a potential across the device of claim 1 .