Organic element for electroluminescent devices
View Patent ↗Disclosed is an electroluminescent device comprising a light emitting layer comprising a boron complex wherein the boron is bonded to a nitrogen atom of a first 5-membered heteroaromatic ring group and to a nitrogen atom of a second 5-membered heteroaromatic ring group, provided that the 5-membered rings are further connected by a methene or an imine bridge to form a six-membered ring, and provided further that at least one of the 5-membered rings contains at least one additional heteroatom that is divalent or trivalent.
1. An electroluminescent device comprising a light emitting layer comprising a boron complex wherein the boron is bonded to a nitrogen atom of a first 5-membered heteroaromatic ring group and to a nitrogen atom of a second 5-membered heteroaromatic ring group, provided that the 5-membered rings are further connected by a methene or an imine bridge to form a six-membered ring, and provided further that at least one of the 5-membered rings contains at least one additional heteroatom that is divalent or trivalent,
wherein the boron complex is represented by Formula 1,
wherein:
Ar 1 represents the atoms necessary to form a five-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;
Y represents N or C—X, wherein X represents a substituent selected from the group consisting of an unsubstituted or substituted heteroaryl group or an unsubstituted aryl group or an aryl group substituted with a substituent selected from halogen, hydroxyl; cyano; carboxyl; alkyl; alkenyl; alkoxy; aryl; aryloxy; carbonamido; sulfonamido; sulfamoyl; carbamoyl; acyl; sulfonyl; sulfonyloxy; sulfinyl; thio; acyloxy; amine; imino; a heterocyclic group, a heterocyclic oxy group or a heterocyclic thio group, each of which may be substituted and which contain a 3 to 7 membered heterocyclic ring composed of carbon atoms and at least one hetero atom selected from the group consisting of oxygen, nitrogen, sulfur, phosphorous, or boron; quaternary ammonium; quaternary phosphonium; and silyloxy; and
L 1 and L 2 represent independently selected substituents.
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 one five-membered ring is fused to an additional aromatic ring group.
5. The device of claim 1 , wherein both five-membered rings are each fused to at least one additional, independently selected, aromatic ring group.
6. The device of claim 1 , wherein the bridge is an imine group.
7. The device of claim 1 , wherein the bridge is a methene group.
8. The device of claim 1 , wherein, Ar 1 and Ar 2 independently represent the atoms necessary to form an imidazole ring group, an oxazole ring group, a thiazole ring group, or a selenazole ring group.
9. The device of claim 1 , wherein L 1 and L 2 represent fluoro substituents.
10. The device of claim 1 , wherein the boron complex is represented by Formula 2,
wherein:
W 1 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 five-membered heteroaromatic ring group;
Y represents N or C—X, wherein X represents a substituent selected from the group consisting of an unsubstituted or substituted heteroaryl group or an unsubstituted aryl group or an aryl group substituted with a substituent selected from halogen, hydroxyl; cyano; carboxyl; alkyl; alkenyl; alkoxy; aryl; aryloxy; carbonamido; sulfonamido; sulfamoyl; carbamoyl; acyl; sulfonyl; sulfonyloxy; sulfinyl; thio; acyloxy; amine; imino; a heterocyclic group, a heterocyclic oxy group or a heterocyclic thio group, each of which may be substituted and which contain a 3 to 7 membered heterocyclic ring composed of carbon atoms and at least one hetero atom selected from the group consisting of oxygen, nitrogen, sulfur, phosphorous, or boron; quaternary ammonium; quaternary phosphonium; and silyloxy groups; and
L 1 and L 2 represent independently selected substituents.
11. The device of claim 10 , wherein V 1 and V 2 independently represent an aryl group or an alkyl group.
12. The device of claim 10 , wherein V 1 and V 2 join together to form an aromatic ring group.
13. The device of claim 1 , wherein the boron complex is represented by Formula 3,
wherein:
W 1 and W 2 independently represent O, S, Se, Te, 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;
Y represents N or C—X, wherein X represents a substituent selected from the group consisting of an unsubstituted or substituted heteroaryl group or an unsubstituted aryl group or an aryl group substituted with a substituent selected from halogen, hydroxyl; cyano; carboxyl; alkyl; alkenyl; alkoxy; aryl; aryloxy; carbonamido; sulfonamido; sulfamoyl; carbamoyl; acyl; sulfonyl; sulfonyloxy; sulfinyl; thio; acyloxy; amine; imino; a heterocyclic group, a heterocyclic oxy group or a heterocyclic thio group, each of which may be substituted and which contain a 3 to 7 membered heterocyclic ring composed of carbon atoms and at least one hetero atom selected from the group consisting of oxygen, nitrogen, sulfur, phosphorous, or boron; guaternary ammonium; quaternary phosphonium; and silyloxy; and
L 1 and L 2 represent independently selected substituents.
14. The device of claim 13 , wherein W represents S.
15. The device of claim 13 , wherein L 1 and L 2 represent fluoro substituents.
16. The device of claim 13 , wherein, independently, at least two of V 3 –V 6 and at least two of V 7 –V 10 combine to form a ring group.
17. The device of claim 13 , wherein Y represents N.
18. The device of claim 13 , wherein Y represents C—X, wherein X is as defined in claim 13 .
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 a host material represented by Formula 4 is present in the light-emitting layer,
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 .