Organic electroluminescent materials and devices

A compound, having the structure of Formula (III) or Formula (IV):

• wherein R1 to R22 are each independently selected from the group consisting of hydrogen, deuterium, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof,
• wherein any two adjacent substituents are optionally joined to form an aromatic or non-aromatic ring,
• wherein at least one of R1, R4, R7, R12, R15 or R18 is aryl, heteroaryl or NRaRb,
• wherein R1 and R12 are phenyl or NRaRb, and
• wherein Ra and Rb are aryl or heteroaryl.

A device comprising an organic light emitting device, said organic light emitting device comprising:

• an anode;
• a cathode;
• and
• an organic layer, disposed between the anode and the cathode, comprising a compound that comprises:
• a fused aromatic ring system comprising a [1,2]azaborino[1,2-a][1,2]azaborine
• moiety;
• wherein the fused aromatic ring system is substituted by one or more substituents, R, that are not fused to the aromatic ring system, selected from the group consisting of deuterium, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;
• wherein any two adjacent substituents, R, are optionally joined to form one or more non-aromatic rings;
• and
• wherein said fused aromatic ring system is selected from the group consisting of a first fused aromatic ring system group and a second fused aromatic ring system group, wherein the first fused aromatic ring system group is selected from the group consisting of:
• which is optionally fused to one or more aromatic rings;
• and
• wherein the second fused aromatic ring system group selected from the group consisting of: