Leigh, VivienneVivienneLeighCarleton, Daniel J.Daniel J.CarletonOlguín, JuanJuanOlguínMüller-Bunz, HelgeHelgeMüller-BunzWright, L. JamesL. JamesWrightAlbrecht, MartinMartinAlbrecht2015-08-192015-08-192014 Ameri2014-07-21Inorganic Chemistryhttp://hdl.handle.net/10197/6823Chelating ligands incorporating both N-[1-alkylpyridin-4(1H)-ylidene]amide (PYA) and N-heterocyclic carbene (NHC) donor sites were prepared and used for the synthesis of ruthenium(II) complexes. Cyclic voltammetry, NMR, and UV–vis spectroscopy of the complexes indicate a solvent-dependent contribution of the limiting resonance structures associated with the ligand in solution. The neutral pyridylidene imine structure is more pronounced in apolar solvents (CH2Cl2), while the mesoionic pyridinium amide form is predominant in polar solvents (MeOH, DMSO). The distinct electronic properties of these hybrid PYA-NHC ligands in different solvents have a direct influence on the catalytic activity of the ruthenium center, e.g., in the dehydrogenation of benzyl alcohol to benzaldehyde. The activity in different solvents qualitatively correlates with the solvent permittivity.enThis document is the unedited author's version of a Submitted Work that was subsequently accepted for publication in Inorganic Chemistry, copyright © American Chemical Society after peer review. To access the final edited and published work, see http://pubs.acs.org/doi/abs/10.1021/ic501026k.RedoxCatalysisJournal Article53158054806010.1021/ic501026k2015-05-13https://creativecommons.org/licenses/by-nc-nd/3.0/ie/