Peripheral engineering of Ir(iii) emitters with imidazo[4,5-b]pyrazin-2-ylidene cyclometalates for blue organic light emitting diodes

A new class of Ir( iii ) carbene complexes with dual N -aryl appendages, the isomeric products of which were successfully isolated and purified by column chromatography, were synthesized followed by catalytic isomerization at elevated temperature.