Heteroleptic osmium complex and method of making the same

A compound having a structure according to Formula I:

• L1-Os-L2
• wherein L1 and L2 are different;
• wherein L1 and L2 are independently selected from ligands having Formula II:
• wherein Y1, Y2 and Y3 comprise C or N;
• wherein R3 and R4 may represent mono-, or di-substitutions, or no substitution;
• wherein R5 may represent mono-, di-, or tri-substitutions, or no substitution;
• wherein R1 and R2 are independently selected from the group consisting of alkyl and cycloalkyl;
• wherein R3, R4 and R5 are independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, and combinations thereof;
• wherein any two adjacent substituents of R1, R2, R3, R4 and R5 are optionally joined to condense into a fused ring;
• and
• wherein the dash lines show the connection points to osmium.

A first device comprising a first organic light emitting device, the 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 the structure according Formula I
• L1-Os-L2;
• wherein L1 and L2 are different;
• wherein L1 and L2 are independently selected from ligands having Formula II:
• wherein Y1, Y2 and Y3 comprise C or N;
• wherein R3 and R4 may represent mono-, or di-substitutions, or no substitution;
• wherein R5 may represent mono-, di-, or tri-substitutions, or no substitution;
• wherein R1 and R2 are independently selected from the group consisting of alkyl and cycloalkyl;
• wherein R3, R4 and R5 are independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, and combinations thereof;
• wherein any two adjacent substituents of R1, R2, R3, R4 and R5 are optionally joined to condense into a fused ring;
• and
• wherein the dash lines show the connection points to osmium.