Organic electroluminescent materials and devices

1. A compound having a formula:

wherein X 1 -X 16 are each independently selected from the group consisting of CR and N;

wherein each R is independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, haloalkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, thioalkoxy, aryloxy, thioaryloxy, amino, arylamino, diarylamino, carbazolyl, silyl, halosilyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acids, nitrile, isonitrile, sulfanyl, phosphino, and combinations thereof;

wherein at least one of X 1 -X 16 is CR;

wherein R is

wherein Y 1 -Y 8 are independently selected from the group consisting of CR′ and N;

wherein each R′ is independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, haloalkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, thioalkoxy, aryloxy, thioaryloxy, amino, arylamino, diarylamino, carbazolyl, aza-carbazolyl, silyl, halosilyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acids, nitrile, isonitrile, sulfanyl, phosphino, and combinations thereof;

wherein at least one of Y 1 to Y 8 is CR′ whose R′ is a group containing at least one carbazole or aza-carbazole.

2. The compound of claim 1 , wherein each of X 1 to X 16 is CR.

3. The compound of claim 1 , wherein at least one of X 1 to X 16 is N.

4. The compound of claim 1 , wherein each of Y 1 to Y 8 is CR′.

5. The compound of claim 1 , wherein at least one of Y 1 to Y 8 is N.

6. The compound of claim 1 , wherein at least one of Y 1 to Y 8 is CR′ whose R′ is a group containing at least one carbazole.

7. The compound of claim 1 , wherein at least one of Y 1 to Y 8 is CR′ whose R′ is a group containing at least one aza-carbazole.

8. The compound of claim 1 , wherein the compound of Formula 2 is selected from the group consisting of:

9. A device comprising one or more organic light emitting devices, at least one of the organic light emitting devices comprising:

an anode;

a cathode; and

an organic layer, disposed between the anode and the cathode, comprising a compound having a formula:

wherein X 1 -X 16 are each independently selected from the group consisting of CR and N;

wherein each R is independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, haloalkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, thioalkoxy, aryloxy, thioaryloxy, amino, arylamino, diarylamino, carbazolyl, silyl, halosilyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acids, nitrile, isonitrile, sulfanyl, phosphino, and combinations thereof;

wherein at least one of X 1 -X 16 is CR;

wherein R is

wherein Y 1 -Y 8 ;

wherein Y 1 to Y 8 are independently selected from the group consisting of CR′ and N;

wherein each R′ is independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, haloalkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, thioalkoxy, aryloxy, thioaryloxy, amino, arylamino, diarylamino, carbazolyl, aza-carbazolyl, silyl, halosilyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acids, nitrile, isonitrile, sulfanyl, phosphino, and combinations thereof;

wherein at least one of Y 1 to Y 8 is CR′; and

wherein R′ is a group containing at least one carbazole or aza-carbazole.

10. The device of claim 9 , wherein each of X 1 -X 16 is CR.

11. The device of claim 9 , wherein at least one of X 1 -X 16 is N.

12. The device of claim 9 , wherein the compound of Formula 2 is selected from the group consisting of:

13. The device of claim 9 , wherein the organic layer is an emissive layer and the compound is a host.

14. The device of claim 9 , wherein the organic layer further comprises a phosphorescent emissive dopant.

15. The device of claim 9 , wherein the organic layer further comprises a phosphorescent emissive dopant, wherein the phosphorescent emissive dopant is a transition metal complex having at least one ligand or part of the ligand if the ligand is more than bidentate, selected from the group consisting of:

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, carboxylic acids, nitrile, isonitrile, sulfanyl, 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 multi-dentate ligand.

16. The device of claim 9 , wherein the organic layer is a charge carrier blocking layer and the compound having Formula I is a charge carrier blocking material in the organic layer.

17. The device of claim 9 , wherein the organic layer is a charge carrier transporting layer and the compound having Formula 2 is a charge carrier transporting material in the organic layer.

18. The device of claim 9 , wherein the device is selected from the group consisting of a consumer product, an electronic component module, and a lighting panel.

19. A formulation comprising the compound in claim 1 .