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;
• wherein K is selected from the group consisting of a direct bond, O, S, NR′, CR′R″, and SiR′R″;
• wherein two adjacent ones of X1 to X4 are C and are fused to form a structure of Formula II,
• wherein the dashed lines indicate direct bonds to ring B;
• wherein each of X1 to X12 independently represents C, CR or N, and each R can be same or different;
• wherein X is selected from the group consisting of O, S, Se, NR′, CR′R″, SiR′R″, Ge′RR″, SnR′R″, BR′, PR′, SbR′, and BiR′;
• wherein RA represent mono to the maximum allowable substitution, or no substitution;
• wherein each R, R′, R″, and RA is independently a hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, boryl, arylalkyl, alkoxy, aryloxy, amino, silyl, gennyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, selenyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;
• wherein LA is coordinated to a metal M through the indicated dashed lines;
• wherein the metal M has an atomic mass greater than 40;
• wherein the metal M can be coordinated to other ligands;
• wherein LA may be joined with other ligands to comprise a tridentate, tetradentate, pentadentate, and hexadentate ligand;
• and
• wherein any two adjacent R, R′, R″, and RA can be joined or fused to form a ring, with the proviso that that
• (1) when X is CR′R″, X5 is CR;
• and
• (2) when X is O, S, Se, or NR′, at least one of the following is true:
• (a) the metal M is further coordinated to at least one substituted or unsubstituted acetylacetonate ligand;
• (b) at least one R comprises an electron withdrawing group;
• (c) at least two RA is not hydrogen or deuterium;
• or
• (d) at least one R is selected from the group consisting of the structures of LIST 1 as defined herein.

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;
• wherein K is selected from the group consisting of a direct bond, O, S, NR′, CR′R″, and SiR′R″;
• wherein two adjacent ones of X1 to X4 are C and are fused to form a structure of Formula II,
• wherein the dashed lines indicate direct bonds to ring B;
• wherein each of X1 to X12 independently represents C, CR or N, and each R can be same or different;
• wherein X is selected from the group consisting of O, S, Se, NR′, CR′R″, SiR′R″, Ge′RR″, SnR′R″, BR′, PR′, SbR′, and BiR′;
• wherein RA represent mono to the maximum allowable substitution, or no substitution;
• wherein each R, R′, R″, and RA is independently a hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, boryl, arylalkyl, alkoxy, aryloxy, amino, silyl, germyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, selenyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;
• wherein LA is coordinated to a metal M through the indicated dashed lines;
• wherein the metal M has an atomic mass greater than 40;
• wherein the metal M can be coordinated to other ligands;
• wherein LA may be joined with other ligands to comprise a tridentate, tetradentate, pentadentate, and hexadentate ligand;
• and
• wherein any two adjacent R, R′, R″, and RA can be joined or fused to form a ring, with the proviso that that
• (1) when X is CR′R″, X5 is CR;
• and
• (2) when X is O, S, Se, or NR′, at least one of the following is true:
• (a) the metal M is further coordinated to at least one substituted or unsubstituted acetylacetonate ligand;
• (b) at least one R comprises an electron withdrawing group;
• (c) at least two RA is not hydrogen or deuterium;
• or
• (d) at least one R is selected from the group consisting of the structures of LIST 1 as defined herein.