Organic electroluminescent materials and devices

1. A compound having Formula I:

wherein X is selected from the group consisting of O, S, Se;

wherein Y is C or Si;

wherein L 1 is selected from the group consisting of a direct bond, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, benzene, pyridine, pyrimidine, pyrazine, pyrrole, oxadiazole, thiadiazole, selenadiazole, and combinations thereof;

wherein L 2 is selected from the group consisting of a direct bond, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, benzene, pyridine, pyrimidine, pyrazine, oxadiazole, thiadiazole, selenadiazole, and combinations thereof;

wherein G 1 is selected from the group consisting of fluorene, dibenzofuran, dibenzoselenophene, triphenylene, tetraphenylene, azafluorene, azacarbazole, azadibenzofuran, azadibenzothiophene, azadibenzoselenophene, azatriphenylene, azatetraphenylene, and combinations thereof;

wherein G 2 is selected from the group consisting of hydrogen, deuterium, halogen, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, aryl, and combinations thereof;

wherein R 1 and R 2 each independently represents none to the maximum available number of substituents;

wherein R 1 and R 2 are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, and combinations thereof;

wherein G 1 , R 1 and R 2 are each independently and optionally further substituted with hydrogen, deuterium, halogen, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, amine, aryl, heteroaryl and combinations thereof;

wherein G 2 is optionally further substituted with hydrogen, deuterium, halogen, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, amine, aryl, and combinations thereof;

wherein G 1 -L 1 is different from G 2 -L 2 and there is no bond between G 1 -L 1 and G 2 -L 2 ; and

wherein the lowest triplet excited state energy of the compound is greater than 2.9 eV.

2. The compound of claim 1 , wherein at least one of L 1 and L 2 is a direct bond.

3. The compound of claim 1 , wherein L 1 and L 2 are each a direct bond.

4. The compound of claim 1 , wherein L 1 is a silyl group.

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

wherein Z 1 is selected from the group consisting of O, S and Se;

wherein R 4 and R 5 are each independently selected from the group consisting of alkyl, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, benzene, and combinations thereof;

wherein R 4 and R 5 are optionally joined to form a ring; and

wherein G 1 can be further substituted.

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

wherein L 2 is selected from the group consisting of:

wherein each occurrence of Z 1 is independently selected from the group consisting of O, S and Se;

wherein R 4 to R 7 are each independently selected from the group consisting of alkyl, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, benzene, and combinations thereof;

wherein R 4 and R 5 are optionally joined to form a ring; and

wherein L 1 and L 2 can each be further substituted.

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

8. 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 Formula I:

wherein X is selected from the group consisting of O, S, Se;

wherein Y is C or Si;

wherein L 1 is selected from the group consisting of a direct bond, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, benzene, pyridine, pyrimidine, pyrazine, pyrrole, oxadiazole, thiadiazole, selenadiazole, and combinations thereof;

wherein L 2 is selected from the group consisting of a direct bond, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, benzene, pyridine, pyrimidine, pyrazine, oxadiazole, thiadiazole, selenadiazole, and combinations thereof;

wherein G 1 is selected from the group consisting of fluorene, dibenzofuran, dibenzoselenophene, triphenylene, tetraphenylene, azafluorene, azacarbazole, azadibenzofuran, azadibenzothiophene, azadibenzoselenophene, azatriphenylene, azatetraphenylene, and combinations thereof;

wherein G 2 is selected from the group consisting of hydrogen, deuterium, halogen, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, aryl, and combinations thereof;

wherein R 1 and R 2 each independently represents none to the maximum available number of substituents;

wherein R 1 and R 2 are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, and combinations thereof;

wherein G 1 , R 1 and R 2 are each independently and optionally further substituted with hydrogen, deuterium, halogen, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, amine, aryl, heteroaryl and combinations thereof;

wherein G 2 is optionally further substituted with hydrogen, deuterium, halogen, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, amine, aryl, and combinations thereof;

wherein G 1 -L 1 is different from G 2 -L 2 and there is no bond between G 1 -L 1 and G 2 -L 2 ; and

wherein the lowest triplet excited state energy of the compound is greater than 2.9 eV.

9. The OLED of claim 8 , wherein the organic layer is an emissive layer and the compound of Formula I is a host.

10. The OLED of claim 8 , 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 X 1 to X 13 is 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.

11. The OLED of claim 8 , wherein the organic layer is a blocking layer and the compound of Formula I is a blocking material in the organic layer.

12. The OLED of claim 8 , wherein the organic layer is a transporting layer and the compound of Formula I is a transporting material in the organic layer.

13. The OLED of claim 8 , wherein the organic layer is an emissive layer and the compound of Formula I is an emitter.

14. The OLED of claim 13 , wherein the OLED emits a luminescent radiation at room temperature when a voltage is applied across the organic light emitting device, and wherein the luminescent radiation comprises a delayed fluorescence process.

15. The OLED of claim 13 , wherein the emissive layer further comprises a host material.

16. The OLED of claim 13 , wherein the emissive layer further comprises a first phosphorescent emitting material.

17. The OLED of claim 16 , wherein the emissive layer further comprises a second phosphorescent emitting material.

18. The OLED of claim 16 , wherein the OLED emits a white light at room temperature when a voltage is applied across the organic light emitting device.

19. A consumer product comprising 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 a formula:

wherein X is selected from the group consisting of O, S, Se;

wherein Y is C or Si;

wherein L 1 is selected from the group consisting of a direct bond, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, benzene, pyridine, pyrimidine, pyrazine, pyrrole, oxadiazole, thiadiazole, selenadiazole, and combinations thereof;

wherein L 2 is selected from the group consisting of a direct bond, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, benzene, pyridine, pyrimidine, pyrazine, oxadiazole, thiadiazole, selenadiazole, and combinations thereof;

wherein G 1 is selected from the group consisting of fluorene, dibenzofuran, dibenzoselenophene, triphenylene, tetraphenylene, azafluorene, azacarbazole, azadibenzofuran, azadibenzothiophene, azadibenzoselenophene, azatriphenylene, azatetraphenylene, and combinations thereof;

wherein G 2 is selected from the group consisting of hydrogen, deuterium, halogen, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, aryl, and combinations thereof;

wherein R 1 and R 2 each independently represents none to the maximum available number of substituents;

wherein R 1 and R 2 are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, and combinations thereof;

wherein G 1 , R 1 and R 2 are each independently and optionally further substituted with hydrogen, deuterium, halogen, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, amine, aryl, heteroaryl and combinations thereof;

wherein G 2 is optionally further substituted with hydrogen, deuterium, halogen, alkyl, ether, alkoxyl, cycloalkyl, cycloalkoxyl, silyl, amine, aryl, and combinations thereof;

wherein G 1 -L 1 is different from G 2 -L 2 and there is no bond between G 1 -L 1 and G 2 -L 2 ; and

wherein the lowest triplet excited state energy of the compound is greater than 2.9 eV.

20. The consumer product of claim 19 , wherein the consumer product is selected from the group consisting of a flat panel 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 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 walls comprising multiple displays tiled together, a theater or stadium screen, and a sign.