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 of Formula I;
• wherein Y is selected from the group consisting of O, S, and Se;
• wherein X1 to X8 are each independently C or N;
• wherein at least two of X1 to X8 are N;
• wherein RA is mono to the maximum allowable substitution;
• wherein at least one RA is -L-ZAr1Ar2Ar3;
• wherein each RA, and Ar1—Ar3 is independently a hydrogen or 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, sulfinyl, sulfonyl, phosphino, selenyl, and combinations thereof;
• wherein Z is Si or Ge;
• wherein L is a direct bond, a substituted or unsubstituted nonfused carbazole, or a substituted or unsubstituted 5H-benzo[d]benzo[4,5]imidazo[1,2-a]imidazole;
• wherein, if L is a substituted nonfused carbazole, Z is directly attached to the carbazole group of the substituted nonfused carbazole;
• when Y1 is O or S, Z is Si, and L is a direct bond, at least one of the following conditions is true:
• 1) X5 is N and one of X1 to X3 is N
• 2) the compound comprises at least 1 carbazole or 5H-benzo[d]benzo[4,5]imidazo[1,2-a]imidazole
• 3) the compound comprises two Si containing groups on one ring
• 4) at least one RA adjacent to each N is different from hydrogen;
• 5) at least one Ar1—Ar3 is not an unsubstituted phenyl
• 6) at least one of RA comprises at least one deuterium any two groups may be joined or fused to form a ring with the proviso that two RA are not joined to form a benzene ring fused to Formula 1.

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 of Formula I;
• wherein Y1 is selected from the group consisting of O, S, and Se;
• wherein X1 to X8 are each independently C or N;
• wherein at least two of X1 to X8 are N;
• wherein RA is mono to the maximum allowable substitution;
• wherein at least one RA is -L-ZAr1Ar2Ar3;
• wherein each RA, and Ar1—Ar3 is independently a hydrogen or 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, sulfinyl, sulfonyl, phosphino, selenyl, and combinations thereof;
• wherein Z is Si or Ge;
• wherein L is a direct bond, a substituted or unsubstituted nonfused carbazole, or a substituted or unsubstituted 5H-benzo[d]benzo[4,5]imidazo[1,2-a]imidazole;
• wherein, if L is a substituted nonfused carbazole, Z is directly attached to the carbazole group of the substituted nonfused carbazole;
• when Y1 is O or S, Z is Si, and L is a direct bond, at least one of the following conditions is true:
• 1) X5 is N and one of X1 to X3 is N
• 2) the compound comprises at least 1 carbazole or 5H-benzo[d]benzo[4,5]imidazo[1,2-a]imidazole
• 3) the compound comprises two Si containing groups on one ring
• 4) at least one RA adjacent to each N is different from hydrogen;
• 5) at least one Ar1—Ar3 is not an unsubstituted phenyl
• 6) at least one of RA comprises at least one deuterium
• any two groups may be joined or fused to form a ring with the proviso that two RA are not joined to form a benzene ring fused to Formula 1.