Stability OLED materials and devices

A phosphorescent compound, wherein the phosphorescent compound is a neutral metal complex of a monodentate, bidentate, tridentate, tetradentate, pentadentate, or hexadentate ligand;

• wherein the ligand comprises at least one first aryl or heteroaryl ring directly bonded to the metal;
• wherein the first ring is substituted by a second ring which is not directly bonded to the metal,
• wherein the first ring is a moiety selected from the group consisting of naphthalene, quinoline, isoquinoline, pyrimidine, pyridazine, pyrrole, oxazole, oxadiazole, thiadiazole, furan, thiophene, pyrazole, and triazole;
• wherein the metal complex is an organometallic complex;
• wherein the ligand comprises at least one carbon bonded to the metal;
• wherein the metal is selected from the group consisting of Re, Ru, Os, Rh, Ir, Cu and Au;
• and
• wherein, when the first ring is pyrrole, pyrazole, oxazole, or triazole, the second ring is selected from group A, and
• wherein, when the first ring is naphthalene, quinoline, isoquinoline, pyrimidine, pyridazine, oxadiazole, thiadiazole, furan, and thiophene, the second ring is selected from group A or group B,
• wherein group B consists of 2,3,4,5,6-pentamethylphenyl, 2,6-dimethyl-4-phenylphenyl, 2,6-dimethyl-4-(3,5-dimethylphenyl)phenyl, 2,6-dimethyl-4-(2,6-dimethylphenyl)phenyl, 2,6-dimethyl-4-(4-pyridyl)phenyl, 2,6-dimethyl-4-(2,6-dimethyl-4-pyridyl)phenyl, 2,4-dimethyl-3-naphthyl, 2,6-dimethyl-4-cyanophenyl, 2,6-dimethyl-4-(9-carbazolyl)phenyl, 2,6-dimethyl-4-(9-phenyl-3-carbazolyl)phenyl, 2,6-dimethyl-4-(2,6-dimethyl-4-cyanophenyl)phenyl, 1,8-dimethyl-9-carbazolyl, 2,6-di-isopropylphenyl, 2,4,6-triisopropylphenyl, 2,6-di-isopropyl-4-phenylphenyl, 2,6-di-isopropyl-4-(3,5-dimethylphenyl)phenyl, 2,6-di-isopropyl-4-(2,6-dimethylphenyl)phenyl, 2,6-di-isopropyl-4-(4-pyridyl)phenyl, 2,6-di-isopropyl-4-(2,6-dimethyl-4-pyridyl)phenyl, 2,4-di-isopropyl-3-naphthyl, 2,6-di-isopropyl-4-cyanophenyl, 2,6-di-isopropyl-4-(9-carbazolyl)phenyl, 2,6-di-isopropyl-4-(9-phenyl-3-carbazolyl)phenyl, 2,6-di-isopropyl-4-(2,6-dimethyl-4-cyanophenyl)phenyl, 2,6-di-tertbutylphenyl, 2,6-di-tert-butyl-4-(3,5-dimethylphenyl)phenyl,
• and
• wherein group A consists of 2,6-di-phenylphenyl, 2,6-di(4-isopropylphenyl)-4-isopropylphenyl, 2,6-di(4-isopropylphenyl)-4-methylphenyl, 2,6-di(4-isopropylphenyl)-4-tert-butylphenyl, 2,4,6-triphenylphenyl, 2,6-di-(4-isopropylphenyl)phenyl, 2,6-di-(3,5-dimethylphenyl)phenyl, 2,4,6-tri(4-isopropylphenyl)phenyl, 2,6-di-(4-tertbutylphenyl)phenyl, 2,6-di-(4-fluorophenyl)phenyl, 2,6-di-(9-carbazolyl)-4-isopropylphenyl, 2,6-di-(9-phenyl-3-carbazolyl)-4-isopropylphenyl, 2,6-di-(4-methoxyphenyl)phenyl, 2,6-diphenyl-4-fluorophenyl, 2,6-di-(2-triphenylenyl)phenyl, 2,6-di-(2-triphenylenyl)-4-isopropylphenyl, 2,6-di-(2,6-dimethyl-4-pyridyl)phenyl, 2,6-di-(4-cyanophenyl)-4-isopropylphenyl, 2,6-di-2-naphthylphenyl, 2,6-di-(4-phenylphenyl)-4-isopropylphenyl, 2,6-di-(3-phenylphenyl)-4-isopropylphenyl, 2,6-di-(4-diphenylaminophenyl)phenyl, 2,6-di-(4-dimethylaminophenyl)phenyl, 2,6-di-(4-trimethylsilylphenyl)phenyl, 2,6-di-(4-triphenylsilylphenyl)phenyl, 2,6-di-(4-diphenylmethylsilylphenyl)phenyl,
• wherein:
• for group B, R1a,e are each independently selected from alkyl;
• for group A, R1a,e are each independently selected from the group consisting of aryl and heteroaryl;
• R1b,d are each independently selected from the group consisting of H, F, cyano, alkoxy, aryloxy, hydrocarbyl, heteroatom substituted hydrocarbyl, aryl, and heteroaryl;
• any two of R1b-d may be linked to form a ring;
• and
• Ar1, Ar2, and Ar3 are each independently aryl or heteroaryl.