Organic electroluminescent materials and devices

1. A compound having a formula selected from the group consisting of Formula I and Formula II:

wherein each occurrence of X 1 is independently selected from the group consisting of NR, SiRR′, GeRR′, O, S, and Se; and

wherein each occurrence of X 2 is independently selected from the group consisting of NR, SiRR′, GeRR′, O, S, and Se;

wherein adjacent substituents of R and R′ are optionally fused or joined to form a ring;

wherein R, R′, and R′ to R 6 are each independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;

with the proviso that, in Formula II, R 5 and R 6 are selected from the group consisting of hydrogen and deuterium; and

wherein at least one of the following conditions is true:

(i) at least one of R 1 to R 6 and R comprises at least one chemical group selected from the group consisting of triphenylene, dibenzoselenophene, aza-triphenylene, aza-carbazole, aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene,

wherein X 1 is selected from the group consisting of Si, Ge, O, S, and Se, X 2 is selected from the group consisting of N, Si, Ge, O, S, and Se, and wherein no more than one of X 1 and X 2 is S; and

wherein X 2 is selected from the group consisting of Si, Ge, O, S, and Se;

(ii) at least one of R 1 to R 6 and R represents a chemical group selected from the group consisting of

wherein X 1 and X 2 are each independently selected from the group consisting of N, NPh, O, S, and Se and wherein no more than one of X 1 and X 2 is S,

wherein each X 2 is independently selected from the group consisting of N, NPh, O, S, and Se, triphenylene, carbazole, dibenzothiophene, dibenzofuran, dibenzoselenophene, aza-triphenylene, aza-carbazole, aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene, each of which is not further substituted;

wherein no more than one of X 1 and X 2 represents N;

wherein when X 1 or X 2 is N, then the N is directly bound to Formula I or Formula II; and

(iii) R 1 to R 6 and R are each independently selected from the group consisting of:

hydrogen,

wherein at least one of R 1 to R 6 and R is not hydrogen, phenyl, or pyridyl.

2. The compound of claim 1 , wherein the compound is represented by Formula I.

3. The compound of claim 1 , wherein the compound is represented by Formula II.

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

wherein R 11 and R 12 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.

5. The compound of claim 1 , wherein R 1 to R 6 and R are each independently selected from the group consisting of hydrogen, aryl, substituted aryl, heteroaryl, and substituted heteroaryl.

6. The compound of claim 1 , wherein at least one of R 1 to R 6 and R comprises at least one chemical group selected from the group consisting of triphenylene, carbazole, dibenzothiophene, dibenzofuran, and dibenzoselenophene; and

wherein at least one of R 1 to R 6 and R comprises at least one chemical group selected from the group consisting of

aza-triphenylene, aza-carbazole, aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene;

wherein each occurrence of X 1 and X 2 is independently selected from the group consisting of N, Si, Ge, O, S, and Se.

7. A compound selected from the group consisting of:

8. A compound of Formula III or Formula IV

wherein X 1 is selected from the group consisting of SiRR′, GeRR′, O, S, and Se;

wherein X 2 is selected from the group consisting of NR, SiRR′, GeRR′, O, S, and Se;

wherein R, R′, R 1 , R 2 , R 3 , R 4 , R 7 , R 8 , R 9 , and R 10 are 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;

wherein adjacent substituents of R and R′ optionally join to form a ring;

wherein at least one of R, R 1 , R 2 , R 3 , R 4 , R 7 , R 8 , R 9 , and R 10 comprises a chemical group selected from the group consisting of silyl, non-fused five-membered heteroaromatic ring, and tetraphenylene;

with the proviso when the compound is of Formula III, the non-fused five-membered heteroaromatic ring is not thiophene or furan;

with the proviso that when the compound is represented by Formula IV, X 2 is NR, and R is substituted or unsubstituted aryl, carbazole, or dibenzofuran, then at least one of R, R 1 , R 2 , R 3 , R 4 , R 7 , R 8 , R 9 , and R 10 comprises a chemical group selected from the group consisting of non-fused five-membered heteroaromatic ring and tetraphenylene; and

with the proviso that when the compound is of Formula IV, R 1 to R 4 are each hydrogen or deuterium, or R 7 to R 10 are each hydrogen or deuterium.

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

an anode; a cathode; and an organic layer disposed between the anode and the cathode, the organic layer comprising a compound of claim 1 .

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

11. The OLED of claim 9 , wherein the organic layer is an emissive layer and the compound is an emissive dopant or a non-emissive dopant.

12. The OLED of claim 9 , 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+1 , OC n H 2n+1 , OAr 1 , N(C n H 2n+1 ) 2 , N(Ar 1 )(Ar 2 ), CH═CH—C n H 2n+1 , C≡CC n H 2n+1 , Ar 1 , Ar 1 -Ar 2 , C n H 2n —Ar 1 , or no substitution;

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.

13. The OLED of claim 9 , wherein the organic layer further comprises a host, wherein host comprises at least one chemical group selected from the group consisting of triphenylene, carbazole, dibenzothiophene, dibenzofuran, dibenzoselenophene, aza-triphenylene, azacarbazole, aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene.

14. The OLED of claim 9 , wherein the organic layer further comprises a host, wherein the host is selected from the group consisting of:

and combinations thereof.

15. A formulation comprising a compound of claim 1 .

16. The compound of claim 8 , wherein at least one of R, R 1 , R 2 , R 3 , R 4 , R 7 , R 8 , R 9 , and R 10 comprises a chemical group selected from the group consisting of:

17. An organic light-emitting device (OLED) comprising: an anode; a cathode; and an organic layer disposed between the anode and the cathode, the organic layer comprising a compound of claim 8 .

18. An organic light-emitting device (OLED) comprising: an anode; a cathode; and an organic layer disposed between the anode and the cathode, the organic layer comprising a compound of claim 7 .

19. The compound of claim 8 , wherein the compound is represented by Formula III.

20. The compound of claim 8 , wherein the compound is represented by Formula IV.