Organic Electroluminescent Materials and Devices

1 .- 15 . (canceled)

16 . A compound of Formula I:

wherein R 1 represents mono, di, tri, or tetra substitution;

wherein R 2 represents mono, di, tri, or tetra substitution, or no substitution;

wherein R 3 represents mono, or di substitution, or no substitution;

wherein R 1 is selected from the group consisting of biphenyl, terphenyl, tetraphenyl, triphenylene, naphthalene, phenanthrene, fluorene, indole, benzofuran, benzothiophene, benzoselenophene, carbazole, dibenzofuran, dibenzothiophene, dibenzoselenophene, pyrimidine, pyrazine, triazine, aza-carbazole, aza-dibenzofuran, aza-dibenzothiophene, aza-dibenzoselenophene, aza-triphenylene, aza-fluorene, quinoline, isoqunoline, quinoxaline, quinazoline, silyl, halogen, and combinations thereof; and

wherein each R 2 , R 3 , R 4 , and R 5 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;

provided that no more than one of R 1 and R 2 represents carbazole; and R 4 and R 5 do not represent dibenzofuran.

17 . The compound of claim 16 , wherein R 1 is selected from the group consisting of triphenylene, fluorene, carbazole, dibenzofuran, dibenzothiophene, dibenzoselenophene, aza-carbazole, aza-dibenzofuran, aza-dibenzothiophene, aza-dibenzoselenophene, aza-triphenylene, aza-fluorene, and combinations thereof.

18 . The compound of claim 16 , wherein each R 2 , R 3 , R 4 , and R 5 are independently selected from the group consisting of aryl, substituted aryl, heteroaryl, and substituted heteroaryl.

19 . A compound of Formula II:

wherein R 2 represents mono, di, tri, or tetra substitution, or no substitution;

wherein R 3 represents mono, or di substitution, or no substitution;

wherein R 1 is selected from the group consisting of biphenyl, terphenyl, tetraphenyl, triphenylene, naphthalene, phenanthrene, fluorene, indole, benzofuran, benzothiophene, benzoselenophene, carbazole, dibenzofuran, dibenzothiophene, dibenzoselenophene, pyrimidine, pyrazine, triazine, aza-carbazole, aza-dibenzofuran, aza-dibenzothiophene, aza-dibenzoselenophene, aza-triphenylene, aza-fluorene, quinoline, isoqunoline, quinoxaline, quinazoline, silyl, halogen, and combinations thereof; and

wherein each R 2 , R 3 , R 4 , and R 5 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.

20 . The compound of claim 16 , wherein R 3 is hydrogen.

21 . The compound of claim 16 , wherein R 4 and R 5 are each independently a phenyl.

22 . The compound of claim 16 , wherein R 2 is hydrogen.

23 . The compound of claim 16 , wherein the compound is selected from the group consisting of:

24 . 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 of Formula I:

wherein R 1 represents mono, di, tri, or tetra substitution;

wherein R 2 represents mono, di, tri, or tetra substitution, or no substitution;

wherein R 3 represents mono, or di substitution, or no substitution;

wherein R 1 is selected from the group consisting of biphenyl, terphenyl, tetraphenyl, triphenylene, naphthalene, phenanthrene, fluorene, indole, benzofuran, benzothiophene, benzoselenophene, carbazole, dibenzofuran, dibenzothiophene, dibenzoselenophene, pyrimidine, pyrazine, triazine, aza-carbazole, aza-dibenzofuran, aza-dibenzothiophene, aza-dibenzoselenophene, aza-triphenylene, aza-fluorene, quinoline, isoqunoline, quinoxaline, quinazoline, silyl, halogen, and combinations thereof; and

wherein each R 2 , R 3 , R 4 , and R 5 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;

provided that no more than one of R 1 and R 2 represents carbazole; and R 4 and R 5 do not represent dibenzofuran.

25 . The OLED of claim 24 , wherein the organic layer is an emissive layer and the compound of Formula I is a host.

26 . The OLED of claim 24 , 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 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, 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.

27 . The OLED of claim 24 , wherein the organic layer is a blocking layer and the compound of Formula I is a blocking material in the organic layer.

28 . The OLED of claim 24 , wherein the organic layer is a transporting layer and the compound of Formula I is a transporting material in the organic layer.

29 . The OLED of claim 24 , 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.

30 . A formulation comprising the compound of claim 16 .

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

an anode;

a cathode; and

an organic layer, disposed between the anode and the cathode, comprising the compound of claim 19 .

32 . A formulation comprising the compound of claim 19 .