Hydrazine-mediated strongly coupled Re(CO)3 dimers

Autor:	Abed Hasheminasab, J. T. Ayers, Hannah M. Rhoda, Christopher J. Ziegler, Richard S. Herrick, Victor N. Nemykin, Laura A. Crandall
Rok vydání:	2015
Předmět:	Schiff base Valence (chemistry) Ligand Dimer Imine Comproportionation Photochemistry Carbon Ruthenium Oxygen Inorganic Chemistry chemistry.chemical_compound Crystallography Hydrazines X-Ray Diffraction chemistry Coordination Complexes One-electron reduction Dimerization Diimine
Zdroj:	Dalton Transactions. 44:17268-17277
ISSN:	1477-9234 1477-9226
DOI:	10.1039/c5dt02821c
Popis:	Dimeric metal complexes can often exhibit coupling interactions via bridging ligands. In this report, we present two Re(CO)3 dimers, where the metals are linked via a bis(pyca) hydrazine (pyca = pyridine-2-carbaldehyde imine) Schiff base ligand. For the dimeric compounds 4 and 5, we observe strong coupling across the dimer as measured by cyclic voltammetry: ∼480 mV separations between the first and the second reduction waves that correspond to comproportionation constants close to 1.5 × 10(8). Evidence for a mixed valence state upon one electron reduction was also observed by spectroelectrochemistry in which a clear inter-valence charge-transfer (IVCT) band was observed in [4]- and [5]-complexes. The electronic structures of all target compounds were probed by DFT and TDDFT computational methods. DFT calculations indicate that reduction takes place at the diimine units, and that the observed coupling is a ligand-based phenomenon, rather than one that involves metal-based orbitals.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c4c8d7558041f3ffc2f58c5457fe0f01 https://doi.org/10.1039/c5dt02821c Zobrazit plný text záznamu