Cationic Heteroleptic Cyclometalated Iridium(III) Complexes Containing Phenyl-Triazole and Triazole-Pyridine Clicked Ligands

Novel heteroleptic iridium complexes containing the 1-substituted-4-phenyl-1H-1,2,3-triazole (phtl) cyclometalating ligand have been synthesized. The 3+2 Huisgen dipolar cycloaddition method (‘click’ chemistry) was utilized to prepare a class of bidentate ligands (phtl) bearing different substituents on the triazole moiety. By using various ligands (phtl-R(1) and pytl-R(2)) (R(1)=adamantane, methyl and R(2)=adamantane, methyl, β-cyclodextrin, ursodeoxycholic acid), we prepared a small library of new luminescent ionic iridium complexes [Ir(phtr-R(1))(2)(pytl-R(2))]Cl and report on their photophysical properties. The flexibility of the clicking approach allows a straightforward control on the chemical-physical properties of the complexes by varying the nature of the substituent on the ligand.