A rhenium(I) complex with indolyl-containing ligand: Synthesis, photophysical properties and theoretical studies

A rhenium(І) tricarbonyl complex, [Re(CO)3(IDIMPhen)Cl] (IDIMPhen-Re) [where IDIMPhen = 2-(3-indolyl)-imidazo[4,5-f]-[1,10]phenanthroline], have been successfully synthesized and fully characterized by 1H NMR, 13C NMR, IR, GC–MS, elemental analysis, UV–Vis and cyclic voltammetry (CV). Meanwhile, the electronic structure and spectroscopic features of IDIMPhen-Re have been investigated using the density functional theory (DFT) and time-dependent DFT methods. Based on the calculated results, the experiment data are explained in great detail. The calculated orbital energies of the HOMO and LUMO of IDIMPhen-Re are in reasonable agreement with those obtained from the electrochemical measurements. The lowest lying singlet → singlet absorption band of IDIMPhen-Re, corresponding to the prominent absorption peak at 447 nm observed in experiments, should be assigned to the pure HOMO → LUMO transition. The calculated IP and EA show that IDIMPhen-Re possesses the good hole-transfer ability and the balanced transport of electrons and holes is more accessible compared with its analogue Phen-Re.

A rhenium(І) tricarbonyl complex [Re(CO)3(IDIMPhen)Cl] (IDIMPhen-Re) have been successfully synthesized and fully characterized by the experimental (UV–Vis, PL and CV) and theoretical (DFT and TDDFT) methods. The experimental data are in agreement with the theoretical results.Figure optionsDownload as PowerPoint slideHighlights
► IDIMPhen-Re metal complexes were synthesized and characterized.
► The corresponding photophysical and electrochemical properties have been investigated.
► HOMO and LUMO are in reasonable agreement with those obtained from the electrochemical measurements.
► The lowest lying absorption band is assigned to the pure HOMO → LUMO transition.
► IDIMPhen-Re possesses the good hole-transfer ability.