Organic electroluminescent materials and devices

1. A compound of Formula (I):

wherein ring A and ring B are each independently a 5- or 6-membered carbocyclic or heterocyclic ring;

wherein L 1 is BR, NR, PR, O, S, Se, C═O, S═O, SO 2 , CRR′, SiRR′, or GeRR′;

wherein Z 1 and Z 2 are independently carbon or nitrogen;

wherein at least one of Z 1 and Z 2 is carbon;

wherein

is a bidentate ligand selected from the group consisting of:

wherein R 1 , R a , R b , R e , and R d may represent no substitution up to the maximum possible substitution;

wherein R 1 , R 2 , R, R′, R′ a , R a , R b , R c , and R d are each independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;

wherein any two adjacent substituents of R 1 , R 2 , R, R′, R a , R b , R c , and R d are optionally joined to form a ring and can be further substituted; and

wherein n is 1 or 2.

2. The compound of claim 1 , wherein

3. The compound of claim 1 , wherein A-L 1 -B is

4. The compound of claim 3 , wherein L 1 is CRR′, wherein R and R′ are alkyl.

5. The compound of claim 4 , wherein CRR′ is C(CH 3 ) 2 .

6. The compound of claim 1 , wherein A-L 1 -B is:

wherein R 6 is selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.

7. The compound of claim 1 , wherein A-L 1 -B is

wherein R 5 is selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.

8. The compound of claim 1 , wherein the ring A is an imidazole ring, which may be substituted as indicated, and Z 1 is nitrogen.

9. The compound of claim 1 , wherein A-L 1 -B is

wherein R 5 and R 6 are each independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.

10. The compound of claim 1 , wherein

is:

and wherein R 7 and R 8 are alkyl.

11. The compound of claim 1 , which is selected from the group consisting of:

12. A first device comprising a first organic light emitting device, comprising:

an anode;

a cathode; and

an organic layer, disposed between the anode and the cathode, comprising a compound of Formula (I):

wherein ring A and ring B are each independently a 5 or 6-membered carbocyclic or heterocyclic ring;

wherein L 1 is BR, NR, PR, O, S, Se, C═O, S═O, SO 2 , CRR′, SiRR′, or GeRR′;

wherein Z 1 and Z 2 are independently carbon or nitrogen;

wherein at least one of Z 1 and Z 2 is carbon;

wherein

is a bidentate ligand selected from the group consisting of:

wherein R 1 , R 2 , R′ a , R a , R b , R c , and R d may represent no substitution up to the maximum possible substitution;

wherein R 1 , R 2 , R, R′, R b , R c , and R d are each independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;

wherein any two adjacent substituents of R 1 , R 2 , R, R′, R a , R b , R c , and R d are optionally joined to form a ring and can be further substituted; and

wherein n is 1 or 2.

13. The first device of claim 12 , wherein the first device is a consumer product.

14. The first device of claim 12 , wherein the first device is an organic light-emitting device.

15. The first device of claim 12 , wherein the first device comprises a lighting panel.

16. The first device of claim 12 , wherein the organic layer is an emissive layer and the compound is an emissive dopant.

17. The first device of claim 12 , wherein the organic layer is an emissive layer and the compound is a non-emissive dopant.

18. The first device of claim 12 , wherein the organic layer further comprises a host.

19. The first device of claim 18 , wherein the host comprises a triphenylene containing benzo-fused thiophene or benzo-fused furan;

wherein any substituent in the host is an unfused substituent independently selected from the group consisting of C n H 2n+1 , OC n H 2n+1 , OAr 1 , N(C n H 2n+1 ) 2 , N(Ar 1 )(Ar 2 ), CH═CH—C n H 2n+1 , C≡CC n H 2n+1 , Ar 1 , Ar 1 —Ar 2 , and C n H 2n —Ar 1 , or the host has no substitutions;

wherein n is from 1 to 10; and

wherein Ar 1 and Ar 2 are independently selected from the group consisting of benzene, biphenyl, naphthalene, triphenylene, carbazole, and heteroaromatic analogs thereof.

20. The first device of claim 18 , wherein the host is selected from the group consisting of:

, and combinations thereof.

21. The first device of claim 18 , wherein the host comprises a metal complex.

22. The first device of claim 18 , wherein the host comprises at least one of the chemical groups selected from the group consisting of carbazole, dibenzothiophene dibenzofuran, dibenzoselenophene, azacarbazole, aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene.