Abstract
A new N-donor ligand, methyl 4-(1-methyl-1H-pyrimidin-2-yl)nicotinate, and an octahedral cationic iridium(III) complex based on it (I) have been synthesized. 1-Benzyl-2-phenyl[2,3]naphthimidazole was used as the cyclometalated ligand, and \({\text{PF}}_{6}^{ - }\) serves as the counterion. Compound I was characterized by 1H, 13C, 19F, 31P, 1H,1H–COSY, and 1H,1H–NOESY NMR spectroscopy, high-resolution mass spectrometry, and X-ray diffraction analysis. Due to the coordination of ligands with extended conjugated systems around the metal ion, the target complex absorbs light up to 700 nm (ε ~ 1000 M–1 cm–1), which accounts for its intense coloration. Complex I exhibits reversible electrochemical behavior in the positive potential range with E1/2 = 0.58 V vs. \({{E}_{{{{{\text{F}}{{{\text{c}}}^{ + }}} \mathord{\left/ {\vphantom {{{\text{F}}{{{\text{c}}}^{ + }}} {{\text{Fc}}}}} \right. \kern-0em} {{\text{Fc}}}}}}}\) . Based on its key characteristics, the obtained compound surpasses most iridium analogs and appears promising for further evaluation in photovoltaic devices.
