1. 2-Azabutadiene complexes of rhenium(<scp>i</scp>): S,N-chelated species with photophysical properties heavily governed by the ligand hidden traits
- Author
-
Yoann Rousselin, Carsten Strohmann, Rodolphe Kinghat Tangou, Michael Knorr, Abderrahim Khatyr, Paul-Ludovic Karsenti, Pierre D. Harvey, Adrien Schlachter, Fabrice Guyon, Frank Juvenal, Marek M. Kubicki, Département de chimie [Sherbrooke] (UdeS), Faculté des sciences [Sherbrooke] (UdeS), Université de Sherbrooke (UdeS)-Université de Sherbrooke (UdeS), Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Technische Universität Dortmund [Dortmund] (TU), Institut de Chimie Moléculaire de l'Université de Bourgogne [Dijon] (ICMUB), and Centre National de la Recherche Scientifique (CNRS)-Université de Bourgogne (UB)-Institut de Chimie du CNRS (INC)
- Subjects
010405 organic chemistry ,Ligand ,chemistry.chemical_element ,Crystal structure ,Rhenium ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Crystallography ,Thioether ,chemistry ,Excited state ,[CHIM]Chemical Sciences ,Singlet state ,Phosphorescence ,Trifluoromethanesulfonate - Abstract
International audience; The reaction of [Re(CO)3(THF)(μ-Br)]2 or [Re(CO)5X] (X = Cl, Br, I) with the diaryl-2-azabutadienes [(RS)2C[double bond, length as m-dash]C(H)–N[double bond, length as m-dash]CAr2] containing two thioether arms at the 4,4-position forms the luminescent S,N-chelate complexes fac-[(OC)3ReX{(RS)2C[double bond, length as m-dash]C(H)–N[double bond, length as m-dash]CAr2}] (1a–h). The halide abstraction by silver triflate converts [(OC)3ReCl{(PhS)2C[double bond, length as m-dash]C(H)–N[double bond, length as m-dash]CPh2}] (1c) to [(OC)3Re(OS([double bond, length as m-dash]O)2CF3){(PhS)2C[double bond, length as m-dash]C(H)–N[double bond, length as m-dash]CPh2}] (1j) bearing a covalently bound triflate ligand. The cyclic voltammograms reveal reversible S^N ligand-centred reduction and irreversible oxidation waves for all complexes. The crystal structures of nine octahedral complexes have been determined along with that of (NaphtylS)2C[double bond, length as m-dash]C(H)–N[double bond, length as m-dash]CPh2 (L6). A rich system of weak non-covalent intermolecular secondary interactions through CH⋯X(Cl, Br)Re, CH⋯O, CO⋯π(Ph), CH⋯πCO, CH⋯O and CH⋯S contacts has been evidenced. The photophysical properties have been investigated by steady-state and time-resolved absorption (fs transient absorption, fs-TAS) and emission (ns-TCSPC and ps-Streak camera) spectroscopy in 2-MeTHF solution at 298 and 77 K. The emission bands are composed of either singlet (450 < λmax < 535 nm) and/or triplet emissions (at 77 K only, λmax < 640 nm, or appearing as a tail at λ > 600 nm), which decay in a multiexponential manner for the fluorescence (short ps (i.e.
- Published
- 2021