Organic electroluminescent materials and devices

An organic light emitting device (OLED) comprising:

• an anode;
• a cathode;
• and
• an organic layer disposed between the anode and the cathode, wherein the organic layer comprises a compound comprising a first ligand LA of Formula I,
• wherein:
• ring A is a 5-membered or 6-membered carbocyclic or heterocyclic ring;
• K is selected from the group consisting of a direct bond, O, and S;
• X1 to X8 are each independently C or N;
• Y is selected from the group consisting of BR, BRR′, NR, PR, P(O)R, O, S, Se, C═O, C═S, C═Se, C═NR′, C═CR′R″, S═O, SO2, CR, CRR′, SiRR′, GeRR′, and combinations thereof;
• Z1 and Z2 are each independently C or N;
• the one of X1 to X4 bonded to Z2 is C;
• each of RA, RB, and RC independently represents mono to the maximum allowable substitution, or no substitution;
• each R, R′, R″, RA, RB, RC, and R1 is independently a hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, germyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, selenyl, and combinations thereof;
• LA is coordinated to a metal M by the dashed lines, and metal M is selected from the group consisting of Rh, Re, Ru, Os, Pt, Pd, Ag, Au, and Cu;
• metal M may be coordinated to other ligands to comprise a tridentate or tetradentate ligand;
• any two substituents may be joined or fused to form a ring;
• wherein (i) at least one RC is a cyclic group that is not fused to ring C, or (ii) ring A has a structure of Formula II,
• and ring A is bonded to ring B at X1;
• or (iii) both (i) and (ii), with the proviso that if ring A is a pyridine ring, M is Pt, K is a direct bond, and RC at X8 is a phenyl ring, then RC at X7 is not a fluorine atom.

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, wherein the organic layer comprises a compound comprising a first ligand LA of Formula I,
• wherein:
• ring A is a 5-membered or 6-membered carbocyclic or heterocyclic ring;
• K is selected from the group consisting of a direct bond, O, and S;
• X1 to X8 are each independently C or N;
• Y is selected from the group consisting of BR, BRR′, NR, PR, P(O)R, O, S, Se, C═O, C═S, C═Se, C═NR′, C═CR′R″, S═O, SO2, CR, CRR′, SiRR′, GeRR′, and combinations thereof;
• Z1 and Z2 are each independently C or N;
• the one of X1 to X4 bonded to Z2 is C;
• each of RA, RB, and RC independently represents mono to the maximum allowable substitution, or no substitution;
• each R, R′, R″, RA, RB, RC, and R1 is independently a hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, germyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, selenyl, and combinations thereof;
• LA is coordinated to a metal M by the dashed lines, and metal M is selected from the group consisting of Rh, Re, Ru, Os, Pt, Pd, Ag, Au, and Cu;
• metal M may be coordinated to other ligands to comprise a tridentate or tetradentate ligand;
• any two substituents may be joined or fused to form a ring;
• wherein (i) at least one RC is a cyclic group that is not fused to ring C, or (ii) ring A has a structure of Formula II,
• and ring A is bonded to ring B at X1;
• or (iii) both (i) and (ii), with the proviso that if ring A is a pyridine ring, M is Pt, K is a direct bond, and RC at X8 is a phenyl ring, then RC at X7 is not a fluorine atom.