Organic electroluminescent materials and devices

A first organic light emitting device comprising:

• an anode;
• a cathode;
• and
• an organic layer, disposed between the anode and the cathode, comprising a compound having a Pt tetradentate structure, having the formula selected from the group consisting of:
• wherein rings C and D each independently represents a 5-membered or 6-membered carbocyclic or heterocyclic ring;
• wherein RA, RB1, RC, and RD each independently represent mono, di, tri, tetra-substitution, or no substitution;
• wherein RB2 represents mono, di-substitution, or no substitution,
• wherein L1, L2, and L3 are each independently selected from the group consisting of a direct bond, BR, NR, PR, O, S, Se, C═O, S═O, SO2, SiRR′, GeRR′, alkyl, cycloalkyl, and combinations thereof;
• wherein n1 and n2 are each independently an integer of 1 or 0;
• the sum of n1 and n2 is at least 1;
• when n1 is 0, L1 is not present;
• and when n2 is 0, L2 is not present;
• wherein X is selected from the group consisting of NRE, O, S, and Se;
• wherein RA, RB1, RB2, RC, RD, RE, R, and R′ are each independently selected from the group consisting of hydrogen, deuterium, halide, 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 adjacent RA, RB, RC, RD, RE, R, and R′ are optionally joined to form a ring;
• wherein X3 and X4 each independently selected from the group consisting of carbon and nitrogen;
• and
• wherein one of Q1, Q3, and Q4 is oxygen, the remaining two of Q1, Q3, and Q4 each represents a direct bond.

A formulation comprising a compound having a Pt tetradentate structure, having the formula selected from the group consisting of:

• wherein rings C, and D each independently represent a 5-membered or 6-membered carbocyclic or heterocyclic ring;
• wherein RA, RB1, RC, and RD each independently represent mono, di, tri, or tetra-substitution, or no substitution;
• wherein RB2 represents mono, or di-substitution, or no substitution;
• wherein L1, L2, and L1 are each independently selected from the group consisting of a direct bond, BR, NR, PR, O, S, Se, C═O, S═O, SO2, SiRR′, GeRR′, alkyl, cycloalkyl, and combinations thereof;
• wherein n1 and n2 are each independently an integer of 1 or 0;
• the sum of n1 and n2 is at least 1;
• when n1 is 0, L1 is not present;
• and when n2 is 0, L2 is not present;
• wherein X is selected from the group consisting of NRE, O, S, and Se;
• wherein RA, RB1, RB2, RC, RD, RE, R, and R′ are each independently selected from the group consisting of hydrogen, deuterium, halide, 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 adjacent RA, RB, RC, RD, RE, R, and R′ are optionally joined to form a ring;
• wherein X3 and X4 each independently selected from the group consisting of carbon and nitrogen;
• and
• wherein one of Q1, Q3 and Q4 is oxygen, the remaining two of Q1, Q3 and Q4 each represent a direct bond.