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, wherein LA has a structure of Formula I:
• wherein moiety B is a monocyclic 5-membered or 6-membered carbocyclic ring or a polycyclic fused ring system, wherein the monocyclic ring or each ring of the polycyclic fused ring system is independently a 5-membered to 10-membered carbocyclic or heterocyclic ring;
• wherein X1-X4 are each independently C or N;
• wherein Z1, Z2, and Z3 are each independently C or N;
• wherein K1 and K2 are each independently selected from the group consisting of a direct bond, O, S, N(Rα), P(Rα), B(Rα), C(Rα)(Rβ), and Si(Rα)(Rβ);
• wherein at least one of K1 and K2 is a direct bond;
• wherein if K1 is a direct bond, then Z1 is C;
• wherein if K2 is a direct bond, then Z3 is C;
• wherein Y is selected from the group consisting of GeRR′, Si(O), Ge(O), Te, P(R), P(O)R, P(S)R, Se(O), Se(O)2, S(O), S(O)2, Te(O), and Te(O)2;
• wherein Z is CR1 or N;
• wherein at least two consecutive X1-X4 are C and are joined to Y and Z through the dashed lines forming a 5-membered ring fused to ring A;
• wherein RA and RB each represent mono to the maximum allowable substitution, or no substitution;
• wherein each R, R′, Rα, Rβ, R1, R2, RA, and RB 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, boryl, selenyl, and combinations thereof;
• and
• wherein any two substituents may be joined or fused to form a ring;
• and
• with the proviso that if Z1 is C and K1 a direct bond, then at least one of X1-X4 is N.

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, wherein LA has a structure of Formula I:
• wherein moiety B is a monocyclic 5-membered or 6-membered carbocyclic ring or a polycyclic fused ring system, wherein the monocyclic ring or each ring of the polycyclic fused ring system is independently a 5-membered to 10-membered carbocyclic or heterocyclic ring;
• wherein X1-X4 are each independently C or N;
• wherein Z1, Z2, and Z3 are each independently C or N;
• wherein K1 and K2 are each independently selected from the group consisting of a direct bond, O, S, N(Rα), P(Rα), B(Rα), C(Rα)(Rβ), and Si(Rα)(Rβ);
• wherein at least one of K1 and K2 is a direct bond;
• wherein if K1 is a direct bond, then Z1 is C;
• wherein if K2 is a direct bond, then Z3 is C;
• wherein Y is selected from the group consisting of GeRR′, Si(O), Ge(O), Te, P(R), P(O)R, P(S)R, Se(O), Se(O)2, S(O), S(O)2, Te(O), and Te(O)2;
• wherein Z is CR1 or N;
• wherein at least two consecutive X1-X4 are C and are joined to Y and Z through the dashed lines forming a 5-membered ring fused to ring A;
• wherein RA and RB each represent mono to the maximum allowable substitution, or no substitution;
• wherein each R, R′, Rα, Rβ, R1, R2, RA, and RB 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, boryl, selenyl, and combinations thereof;
• and
• wherein any two substituents may be joined or fused to form a ring;
• and
• with the proviso that if Z1 is C and K1 a direct bond, then at least one of X1-X4 is N.