Organic electroluminescent materials and devices

1. A compound having a formula M(L A ) x (L B ) y (L C ) z :

wherein the ligand L A is

wherein the ligand L B is

wherein the ligand L C is

wherein M is a metal having an atomic number greater than 40;

wherein x is 1, or 2;

wherein y is 1, or 2;

wherein z is 0, 1, or 2;

wherein x+y+z is the oxidation state of the metal M;

wherein X 1 , X 2 , X 3 , and X 4 are independently C or N, with the proviso that at least two of X 1 , X 2 , X 3 , and X 4 that are adjacent to each other are carbon;

wherein R 1 , R 2 , R 3 , and R 4 are independently selected from the group consisting of alkyl, cycloalkyl, aryl, and heteroaryl;

wherein each one of R 1 , R 2 , R 3 , and R 4 has at least two C atoms;

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;

wherein rings A, C, and D are each independently a 5 or 6-membered carbocyclic or heterocyclic ring;

wherein R A , R C , and R D each independently represent mono, di, tri, or tetra-substitution, or no substitution;

wherein R B represents di, tri, or tetra-substitution, with the proviso that R B is attached only to those of X 1 , X 2 , X 3 , and X 4 that are carbon;

wherein two adjacent R B form a six-member carbocyclic or heterocyclic ring E fused to ring B; wherein, when ring E is heterocyclic, the only heteroatom is nitrogen; and wherein ring E can be further substituted;

wherein (a) at least one of X 1 , X 2 , X 3 , and X 4 is N,

(b) ring E is heterocyclic, or

(c) both;

wherein each R A , R C , and R D , and any R B other than the two that form ring E, is 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 adjacent substituents of R A , R C , and R D are optionally joined to form a fused ring.

2. The compound of claim 1 , wherein M is selected from the group consisting of Ir, Rh, Re, Ru, Os, Pt, Au, and Cu.

3. The compound of claim 1 , wherein M is Ir.

4. The compound of claim 1 , wherein ring A is benzene.

5. The compound of claim 1 , wherein z is 1 or 2, ring C is benzene, and ring D is pyridine.

6. The compound of claim 1 , wherein R 5 is selected from the group consisting of hydrogen, deuterium, alkyl, cycloalkyl, and combinations thereof.

7. The compound of claim 1 , wherein R 5 is hydrogen.

8. The compound of claim 1 , wherein R 1 , R 2 , R 3 , and R 4 are alkyl or cycloalkyl.

9. The compound of claim 1 , wherein R 1 , R 2 , R 3 , and R 4 are independently selected from the group consisting of ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, cyclobutyl, cyclopentyl, cyclohexyl, partially or fully deuterated variants thereof, and combinations thereof.

10. The compound of claim 1 , wherein the compound is selected from the group consisting of:

wherein X 5 , X 6 , X 7 , and X 8 are C or N;

wherein R 7 , and R 8 each independently represent mono, di, tri, or tetra-substitution, or no substitution;

wherein R 6 , R 7 , and R 8 are 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, in Formula III, X 3 , X 4 or both are N, R B is attached to X 3 only when X 3 is carbon, and R B is attached to X 4 only when X 4 is carbon; and

wherein n is 1 or 2.

11. The compound of claim 10 , wherein R 6 , and R 7 are independently selected from the group consisting of hydrogen, deuterium, alkyl, cycloalkyl, and combinations thereof.

12. The compound of claim 10 , wherein R 8 is selected from the group consisting of hydrogen, deuterium, alkyl, cycloalkyl, halide, and combinations thereof.

13. The compound of claim 10 , wherein n is 2.

14. The compound of claim 1 , wherein the compound is selected from the group consisting of:

wherein R 7 , and R 8 each independently represent mono, di, tri, or tetra-substitution, or no substitution;

wherein R 6 , R 7 , and R 8 are 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 n is 1 or 2.

15. The compound of claim 1 , wherein L A is selected from the group consisting of L A1 to L A270 listed below:

16. The compound of claim 15 , wherein x=1 or 2, y=1 or 2, and z=0, and wherein L B is selected from the group consisting of L B1 , L B2 , L B5 , L B7 , L B9 , L B10 , and L B13 listed below:

17. The compound of claim 1 , wherein L B is selected from the group consisting of L B1 , L B2 , L B5 , L B7 , L B9 , L B10 , and L B13 listed below:

18. The compound of claim 1 , wherein the compound is selected from the group consisting of:

19. A first device comprising a first organic light emitting device, the first organic light emitting device comprising:

an anode;

a cathode; and

an organic layer, disposed between the anode and the cathode, comprising a compound having a formula M(L A ) x (L B ) y (L C ) z :

wherein the ligand L A is

wherein the ligand L B is

wherein the ligand L C is

wherein M is a metal having an atomic number greater than 40;

wherein x is 1, or 2;

wherein y is 1, or 2;

wherein z is 0, 1, or 2;

wherein x+y+z is the oxidation state of the metal M;

wherein X 1 , X 2 , X 3 , and X 4 are independently C or N, with the proviso that at least two of X 1 , X 2 , X 3 , and X 4 that are adjacent to each other are carbon;

wherein R 1 , R 2 , R 3 , and R 4 are independently selected from the group consisting of alkyl, cycloalkyl, aryl, and heteroaryl;

wherein each one of R 1 , R 2 , R 3 , and R 4 has at least two C atoms;

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;

wherein rings A, C, and D are each independently a 5 or 6-membered carbocyclic or heterocyclic ring;

wherein R A , R C , and R D each independently represent mono, di, tri, or tetra-substitution, or no substitution;

wherein R B represents di, tri, or tetra-substitution, with the proviso that R B is attached only to those of X 1 , X 2 , X 3 , and X 4 that are carbon;

wherein two adjacent R B form a six-member carbocyclic or heterocyclic ring E fused to ring B; wherein, when ring E is heterocyclic, the only heteroatom is nitrogen; and wherein ring E can be further substituted;

wherein (a) at least one of X 1 , X 2 , X 3 , and X 4 is N,

(b) ring E is heterocyclic, or

(c) both;

wherein each R A , R C , and R D , and any R B other than the two that form ring E, is 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 adjacent substituents of R A , R C , and R D are optionally joined to form a fused ring.

20. A formulation comprising a compound having a formula M(L A ) x (L B ) y (L C ) z :

wherein the ligand L A is

wherein the ligand L B is

wherein the ligand L C is

wherein M is a metal having an atomic number greater than 40;

wherein x is 1, or 2;

wherein y is 1, or 2;

wherein z is 0, 1, or 2;

wherein x+y+z is the oxidation state of the metal M;

wherein X 1 , X 2 , X 3 , and X 4 are independently C or N, with the proviso that at least two of X 1 , X 2 , X 3 , and X 4 that are adjacent to each other are carbon;

wherein R 1 , R 2 , R 3 , and R are independently selected from the group consisting of alkyl, cycloalkyl, aryl, and heteroaryl;

wherein each one of R 1 , R 2 , R 3 , and R 4 has at least two C atoms;

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;

wherein rings A, C, and D are each independently a 5 or 6-membered carbocyclic or heterocyclic ring;

wherein R A , R C , and R D each independently represent mono, di, tri, or tetra-substitution, or no substitution;

wherein R B represents di, tri, or tetra-substitution, with the proviso that R B is attached only to those of X 1 , X 2 , X 3 , and X 4 that are carbon;

wherein two adjacent R B form a six-member carbocyclic or heterocyclic ring E fused to ring B; wherein, when ring E is heterocyclic, the only heteroatom is nitrogen; and wherein ring E can be further substituted;

wherein (a) at least one of X 1 , X 2 , X 3 , and X 4 is N,

(b) ring E is heterocyclic, or

(c) both;

wherein each R A , R C , and R D , and any R B other than the two that form ring E, is 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 adjacent substituents of R A , R C , and R D are optionally joined to form a fused ring.