Synthesis, structural characterization and photocatalytic evaluation of cyclometalated iridium(III) complexes containing fluorescent bis-amide bipyridine ligands

Cyclometalated iridium(III) complexes have remarkable photophysical, electrochemical, and biological properties, making them promising candidates for applications in organic light-emitting devices (OLEDs), photocatalysis, and medicinal chemistry. In this work, we report the synthesis and structural characterization of three new heteroleptic iridium(III) complexes: [Ir(ppy)₂(BAN)]Cl, [Ir(ppy)₂(BAD)]Cl and [Ir(ppy)₂(BAF)]Cl, 2-phenylpyridine (ppy) as cyclometalating ligands and ancillary ligands derived from fluorescent bis-amide functionalized bipyridines. The complexes were obtained via classical coordination reactions with purification using chromatographic methods. Characterization was performed using elemental analysis, infrared spectroscopy, ¹H and ¹³C nuclear magnetic resonance (NMR) spectroscopy and single-crystal X-ray diffraction. These techniques confirmed the chemical composition and proposed molecular structures, as well as allowing for the investigation of the coordination environment around the metal center. In addition, to the structural characterization, the complexes were evaluated for their photophysical and photocatalytic properties. The noteworthy results confirm the potentiality of cyclometalated iridium(III) complexes as multifunctional materials for advanced applications.