Synthesis of four coordinated platinum complexes and their applications in light emitting devices thereof

A compound represented by the formula:

• wherein:
• each R1 in (R1)2 independently represents hydrogen, halogen, hydroxyl, amino, nitro, thiol, or optionally substituted C1-C4 alkyl;
• each R2 in (R2)2 independently represents hydrogen, hydroxyl, amino, nitro, thiol, or optionally substituted C1-C4 alkyl;
• Y1a represents O, S, NR4a, wherein R4a represents optionally substituted C1-C4 alkyl;
• Si(R4b)2, wherein each R4b in (R4b)2 independently represents optionally substituted C1-C4 alkyl;
• n is 1;
• Y1b represents O, S, NR5a, wherein R5a represents optionally substituted C1-C4 alkyl;
• Si(R5b)2, wherein each R5b in (R5b)2 independently represents optionally substituted C1-C4 alkyl;
• or C(R5c)2, wherein each R5c in (R5c)2 represents hydrogen or optionally substituted C1-C4 alkyl;
• each of Y2a, Y2b, Y2c, and Y2d independently represents N, NR6a, C, or CR6b, wherein each of R6a and R6b independently represents hydrogen, optionally substituted C1-C4 alkyl;
• each of Y3a, Y3b, Y3c, Y3d, Y3e, Y4a, Y4b, Y 4c, and Y4dindependently represents N, NR6a, C, or CR6b, wherein each of R6a and R6b independently represents hydrogen or optionally substituted C1-C4 alkyl;
• or Z(R6c)2, wherein Z is C or Si, and wherein each R6c in (R6c)2 independently represents hydrogen or optionally substituted C1-C4 alkyl;
• m is 1 or 2;
• the open dotted circle
• indicates partial or full unsaturation of the ring with which it is associated;
• and
• the optional substituents for each C1-C4 are selected from the group consisting of alkyl, cycloalkyl, alkoxy, amino, ether, halide, hydroxyl, nitro, silyl, sulfo-oxo, and thiol,
• provided that if m is 1, each of Y2aand Y2d is CH and each of Y2b and Y2c is N, then at least one of Y4a, Y4b, Y3a, or Y3d is not N.