Organic electroluminescent materials and devices

1. A heteroleptic compound having a formula Ir(L A ) n (L B ) 3−n ;

wherein the ligand L A is

wherein the ligand L B is selected from the group consisting of:

wherein, if L B is

 at least one of X 5 to X 8 is N;

wherein each X 1 to X 13 are independently selected from the group consisting of carbon and nitrogen;

wherein X is selected from the group consisting of BR′, NR′, PR′, O, S, Se, C═, S═O, SO 2 , CR′R″, SiR′R″, and GeR′R″;

wherein R′ and R″ are optionally fused or joined to form a ring;

wherein each R a , R b , R c , and R d may represent from mono substitution to the possible maximum number of substitution, or no substitution;

wherein R′, R″, 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; and

wherein any two adjacent substituents of R a , R b , R c , and R d are optionally fused or joined to form a ring or form a multidentate ligand

wherein L A is a different ligand from L B ;

wherein n is 1 or 2;

wherein R A represents mono, di, tri, or tetra-substitution, or no substitution;

wherein R B represents mono, di, tri, or tetra-substitution;

wherein X 3 of ligand L A is C and R B at X 3 has the following structure:

wherein R A and R B are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof, and any two adjacent R B are optionally joined or fused into a ring;

adjacent R A cannot be joined or fused into a ring;

wherein R 1 and R 2 are each independently selected from the group consisting of alkyl, cycloalkyl, partially fluorinated alkyl, partially fluorinated cycloalkyl, and their partially deuterated or fully deuterated analogs, and combinations thereof;

wherein R 1 and R 2 are each attached to the ring E by a carbon; and

wherein at least one of R 1 and R 2 is selected from the group consisting of:

2. The compound of claim 1 , wherein X 1 , X 2 , X 3 , and X 4 are each a carbon.

3. The compound of claim 1 , wherein at least one of R 1 and R 2 is selected from the group consisting of:

4. The compound of claim 1 , wherein the ligand L B is selected from the group consisting of:

5. The compound of claim 1 , wherein the ligand L B is selected from the group consisting of:

6. The compound of claim 1 , wherein the ligand L B is

7. The compound of claim 1 , wherein the ligand L B is

and at least one of X 5 to X 8 is N.

8. The compound of claim 1 , wherein wherein the ligand L B is

9. The compound of claim 1 , wherein at least one of R 1 and R 2 is selected from the group consisting of:

10. The compound of claim 1 , wherein at least one of R 1 and R 2 is selected from the group consisting of:

11. The compound of claim 1 , wherein R 1 and R 2 are different; and

each of R 1 and R 2 is independently selected from the group consisting of:

12. The compound of claim 1 , wherein R B represents di, tri, or tetra-substitution; and at least two R B are other than hydrogen or deuterium.

13. A formulation comprising the heteroleptic compound of claim 1 .

14. A first organic light emitting device comprising:

an anode;

a cathode; and

an organic layer, disposed between the anode and the cathode, comprising a heteroleptic compound having a formula Ir(L A ) n (L B ) 3-n :

wherein the ligand L A is

wherein the ligand L B is selected from the group consisting of:

wherein, if L B is

at least one of X 5 to X 8 is N;

wherein each X 1 to X 13 are independently selected from the group consisting of carbon and nitrogen;

wherein X is selected from the group consisting of BR′, NR′, PR′, O, S, Se, C═O, S═O, SO 2 , CR′R″, SiR′R″, and GeR′R″;

wherein R′ and R″ are optionally fused or joined to form a ring;

wherein each R a , R b , R c , and R d may represent from mono substitution to the possible maximum number of substitution, or no substitution;

wherein R′, R″, 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; and

wherein any two adjacent substituents of R a , R b , R c , and R d are optionally fused or joined to form a ring or form a multidentate ligand

wherein L A is a different ligand from L B ;

wherein n is 1 or 2;

wherein R A represents mono, di, tri, or tetra-substitution, or no substitution;

wherein R B represents mono, di, tri, or tetra-substitution;

wherein X 3 of ligand L A is C and R B at X 3 has the following structure:

wherein R A and R B are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof, and any two adjacent R B are optionally joined or fused into a ring;

adjacent R A cannot be joined or fused into a ring;

wherein R 1 and R 2 are each independently selected from the group consisting of alkyl, cycloalkyl, partially fluorinated alkyl, partially fluorinated cycloalkyl, and their partially deuterated or fully deuterated analogs, and combinations thereof;

wherein R 1 and R 2 are each attached to the ring E by a carbon; and

wherein at least one of R 1 and R 2 is selected from the group consisting of:

15. The first organic light emitting device of claim 14 , wherein the first organic light emitting device is incorporated into a device selected from the group consisting of a consumer product, an electronic component module, an organic light-emitting device, and a lighting panel.

16. The first organic light emitting device of claim 14 , wherein the organic layer is an emissive layer and the compound is an emissive dopant or a non-emissive dopant.

17. The first organic light emitting device of claim 14 , wherein the organic layer further comprises a host, 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+i , OC n H 2n+i , OAr 1 , N(C n H) 2 , N(Ar 1 )(Ar 2 ), CH═CH—C n H 2n+1 , C≡C—C 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.

18. The first organic light emitting device of claim 14 , wherein the organic layer further comprises a host, wherein host comprises at least one chemical group selected from the group consisting of carbazole, dibenzothiophene, dibenzofuran, dibenzoselenophene, azacarbazole, aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene.

19. The first organic light emitting device of claim 14 , wherein the organic layer further comprises a host, wherein the host is selected from the group consisting of:

and combinations thereof.

20. The first organic light emitting device of claim 14 , wherein the organic layer further comprises a host, wherein the host comprises a metal complex.