Organic electroluminescent materials and devices

1. A compound having the formula:

wherein Ar and Ar′ are independently selected from the group consisting of phenyl, biphenyl, naphthalene, pyridine, pyrazine, pyrimidine, triazine, benzonitrile, dibenzothiophene, dibenzofuran, dibenzoselenophene, aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene, which are optionally further substituted with at least one substituent R 1 ;

wherein Z is selected from Si and Ge;

wherein L is a non-fused aromatic group comprising at least one group selected from the group consisting of pyridine, pyrazine, pyrimidine, triazine, benzonitrile, and combinations thereof;

wherein L is optionally further substituted with at least one substituent R 1 ;

wherein A is directly bonded to Z and is selected from the group consisting of dibenzofuran, dibenzothiophene, dibenzoselenophene, azadibenzofuran, azadibenzothiophene, azadibenzoselenophene, and combinations thereof, which are optionally further substituted with at least one substituent R 1 ; and

wherein B comprises a group selected from the group consisting of carbazole, azacarbazole, and combinations thereof, which are optionally further substituted with at least one substituent R 1 ;

wherein each R 1 can be the same or different and is independently selected from the group consisting of 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 R 1 are optionally joined or fused into a ring.

2. The compound of claim 1 , wherein each R 1 is independently selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, heteroalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, aryl, heteroaryl, nitrile, isonitrile, and combinations thereof.

3. The compound of claim 1 , wherein A is selected from the group consisting of

wherein Y 1 and Y 2 are each independently selected from the group consisting of O, S, and Se;

wherein X 1 to X 10 are each independently selected from the group consisting of CR′ and N, and wherein each six-membered ring contains at most one N;

wherein each R′ is independently selected from the group consisting of hydrogen, deuterium, fluorine, alkyl, cycloalkyl, heteroalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, aryl, heteroaryl, nitrile, isonitrile, and combinations thereof.

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

wherein R is selected from the group consisting of hydrogen, deuterium, fluorine, alkyl, cycloalkyl, heteroalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, aryl, heteroaryl, nitrile, isonitrile, and combinations thereof.

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

6. The compound of claim 1 , wherein L is selected from the group consisting of pyridine, pyrazine, pyrimidine, triazine, benzonitrile, and combinations thereof;

wherein L is optionally further substituted with at least one substituent R 1 .

7. The compound of claim 1 , wherein Ar and Ar′ are phenyl.

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

9. An organic light emitting device (OLED) comprising:

an anode;

a cathode; and

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

wherein Ar and Ar′ are independently selected from the group consisting of phenyl, biphenyl, naphthalene, pyridine, pyrazine, pyrimidine, triazine, benzonitrile, dibenzothiophene, dibenzofuran, dibenzoselenophene, aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene, which are optionally further substituted with at least one substituent R 1 ;

wherein Z is selected from Si and Ge;

wherein L is a non-fused aromatic group comprising at least one group selected from the group consisting of pyridine, pyrazine, pyrimidine, triazine, benzonitrile, and combinations thereof;

wherein L is optionally further substituted with at least one substituent R 1 ;

wherein A is directly bonded to Z and is selected from the group consisting of dibenzofuran, dibenzothiophene, dibenzoselenophene, azadibenzofuran, azadibenzothiophene, azadibenzoselenophene, and combinations thereof, which are optionally further substituted with at least one substituent R 1 ; and

wherein B comprises a group selected from the group consisting of carbazole, azacarbazole, and combinations thereof, which are optionally further substituted with at least one substituent R 1 ;

wherein each R 1 can be same or different and is independently selected from the group consisting of 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 R 1 are optionally joined or fused into a ring.

10. The OLED of claim 9 , wherein the organic layer is an emissive layer and the compound of Formula I is a host.

11. The OLED of claim 9 , wherein the organic layer further comprises a phosphorescent emissive dopant; wherein the 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 Y 1 to Y 13 are independently selected from the group consisting of carbon and nitrogen;

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

wherein R e and R f are optionally fused or joined to form a ring;

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

wherein each R a , R b , R c , R d , R e , and R f is independently selected from the group consisting of hydrogen, deuterium, fluorine, alkyl, cycloalkyl, heteroalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, aryl, heteroaryl, nitrile, isonitrile, 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.

12. The OLED of claim 9 , wherein the organic layer is a blocking layer and the compound of Formula I is a blocking material in the organic layer.

13. The OLED of claim 9 , wherein the organic layer is a transporting layer and the compound of Formula I is a transporting material in the organic layer.

14. The OLED of claim 9 , wherein the organic layer is an emissive layer and the compound of Formula I is an emitter.

15. A consumer product comprising an organic light-emitting device comprising:

an anode;

a cathode; and

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

wherein Ar and Ar′ are independently selected from the group consisting of phenyl, biphenyl, naphthalene, pyridine, pyrazine, pyrimidine, triazine, benzonitrile, dibenzothiophene, dibenzofuran, dibenzoselenophene, aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene, which are optionally further substituted with at least one substituent R 1 ;

wherein Z is selected from Si and Ge;

wherein L is a non-fused aromatic group comprising at least one group selected from the group consisting of pyridine, pyrazine, pyrimidine, triazine, benzonitrile, and combinations thereof;

wherein L is optionally further substituted with at least one substituent R 1 ;

wherein A is directly bonded to Z and is selected from the group consisting of dibenzofuran, dibenzothiophene, dibenzoselenophene, azadibenzofuran, azadibenzothiophene, azadibenzoselenophene, and combinations thereof, which are optionally further substituted with at least one substituent R 1 ; and

wherein B comprises a group selected from the group consisting of carbazole, azacarbazole, and combinations thereof, which are optionally further substituted with at least one substituent R 1 ;

wherein each R 1 can be same or different and is independently selected from the group consisting of 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 R 1 are optionally joined or fused into a ring.

16. The consumer product of claim 15 , wherein the consumer product is selected from the group consisting of a flat panel display, a curved display, a computer monitor, a medical monitor, a television, a billboard, a light for interior or exterior illumination and/or signaling, a heads-up display, a fully or partially transparent display, a flexible display, a rollable display, a foldable display, a stretchable display, a laser printer, a telephone, a cell phone, tablet, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro-display that is less than 2 inches diagonal, a 3-D display, a virtual reality or augmented reality display, a vehicle, a video wall comprising multiple displays tiled together, a theater or stadium screen, and a sign.