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, Ir(LA)m(LB)3-m, having a structure of Formula I,
• wherein
• each of moiety A and moiety C is independently a 5-membered carbocyclic or heterocyclic ring, a 6-membered carbocyclic or heterocyclic ring, or a polycyclic fused ring system comprising 5-membered and/or 6-membered carbocyclic or heterocyclic rings;
• moiety B is a 5-membered heterocyclic ring;
• Z1, Z2, and Z3 are each independently C or N;
• m is 1 or 2;
• RA, RB, and RC each independently represent mono to the maximum allowable substitution, or no substitution;
• at least one of R1, R2, R3, or R4 has a structure of Formula II,
• or is a 5-membered heterocyclic ring;
• X1 is CR1a or N, X2 is CR2a or N, X3 is CR3a or N, X4 is CR4a or N, and X5 is CR5a or N;
• each of R1, R2, R3, R4, RA, RB, RC, R1a, R2a, R3a, R4a, and R5a is independently hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, boryl, arylalkyl, alkoxy, aryloxy, amino, germyl, selenyl, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;
• at least one of R1a, R2a, R3a, R4a, or R5a is selected from the group consisting of cycloalkyl, alkyl, silyl, germyl, partially or fully deuterated variants thereof, partially or fully fluorinated variants thereof, and combinations thereof;
• if moiety B is imidazole where Z1 is N, then R2 is not silyl or germyl;
• if R3 has Formula II, R3a is alkyl, and each of R1a, R2a, R4a, and R5a is H, then R3a is partially or fully deuterated or R3a comprises at least four carbon atoms;
• if R3 has Formula II and moiety B is imidazole where Z1 is N, then at least one of the following is true:
• (i) at least one of X1 to X5 is N;
• (ii) at least one of R1a or R5a is not hydrogen;
• (iii) at least one of R1a, R2a, R3a, R4a, or R5a comprises aryl, heteroaryl, or cyano;
• (iv) at least two of R2a, R3a, or R4a are selected from the group consisting of cycloalkyl, alkyl, silyl, germyl, partially or fully deuterated variants thereof, partially or fully fluorinated variants thereof, and combinations thereof;
• or
• (v) at least one of R1a, R2a, R3a, R4a, or R5a is partially or fully fluorinated or is silyl, germyl,
• if moiety A is unsubstituted benzene and R1 has a structure of Formula II, where X1 is methyl and each of X2 to X5 is H, then at least one of Z1 or Z2 is C;
• if moiety A is benzene, moiety B is imidazole, moiety C is naphthyl, and at least one of R1, R2, R3, or R4 has a structure of Formula II, then (a) at least one of X1 to X5 is N, or (b) at least one of R1a, R2a, R3a, R4a, R5a is selected from the group consisting of cycloalkyl, alkyl having at least two carbon atoms, silyl, germyl, partially or fully deuterated variants thereof, partially or fully fluorinated variants thereof, and combinations thereof, and
• wherein any two substituents may be joined or fused to form a ring, with the provisos that R1a, R2a, R3a, R4a, and R5a do not form a 6-membered ring and R1 and R2 are not joined or fused to form a benzene ring.

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, Ir(LA)m(LB)3-m, having a structure of Formula I,
• wherein
• each of moiety A and moiety C is independently a 5-membered carbocyclic or heterocyclic ring, a 6-membered carbocyclic or heterocyclic ring, or a polycyclic fused ring system comprising 5-membered and/or 6-membered carbocyclic or heterocyclic rings;
• moiety B is a 5-membered heterocyclic ring;
• Z1, Z2, and Z3 are each independently C or N;
• m is 1 or 2;
• RA, RB, and RC each independently represent mono to the maximum allowable substitution, or no substitution;
• at least one of R1, R2, R3, or R4 has a structure of Formula II,
• or is a 5-membered heterocyclic ring;
• X1 is CR1a or N, X2 is CR2a or N, X3 is CR3a or N, X4 is CR4a or N, and X5 is CR5a or N;
• each of R1, R2, R3, R4, RA, RB, RC, R1a, R2a, R3a, R4a, and R5a is independently hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, boryl, arylalkyl, alkoxy, aryloxy, amino, germyl, selenyl, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;
• at least one of R1a, R2a, R3a, R4a, or R5a is selected from the group consisting of cycloalkyl, alkyl, silyl, germyl, partially or fully deuterated variants thereof, partially or fully fluorinated variants thereof, and combinations thereof;
• if moiety B is imidazole where Z1 is N, then R2 is not silyl or germyl;
• if R3 has Formula II, R3a is alkyl, and each of R1a, R2a, R4a, and R5a is H, then R3a is partially or fully deuterated or R3a comprises at least four carbon atoms;
• if R3 has Formula II and moiety B is imidazole where Z1 is N, then at least one of the following is true:
• (i) at least one of X1 to X5 is N;
• (ii) at least one of R1a or R5a is not hydrogen;
• (iii) at least one of R1a, R2a, R3a, R4a, or R5a comprises aryl, heteroaryl, or cyano;
• (iv) at least two of R2a, R3a, or R4a are selected from the group consisting of cycloalkyl, alkyl, silyl, germyl, partially or fully deuterated variants thereof, partially or fully fluorinated variants thereof, and combinations thereof;
• or
• (v) at least one of R1a, R2a, R3a, R4a, or R5a is partially or fully fluorinated or is silyl, germyl,
• if moiety A is unsubstituted benzene and R1 has a structure of Formula II, where X is methyl and each of X2 to X5 is H, then at least one of Z1 or Z2 is C;
• if moiety A is benzene, moiety B is imidazole, moiety C is naphthyl, and at least one of R1, R2, R3, or R4 has a structure of Formula II, then (a) at least one of X1 to X5 is N, or (b) at least one of R1a, R2a, R3a, R4a, R5a is selected from the group consisting of cycloalkyl, alkyl having at least two carbon atoms, silyl, germyl, partially or fully deuterated variants thereof, partially or fully fluorinated variants thereof, and combinations thereof;
• and
• wherein any two substituents may be joined or fused to form a ring, with the provisos that R1a, R2a, R3a, R4a, and R5a do not form a 6-membered ring and R1 and R2 are not joined or fused to form a benzene ring.