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A series of bimetallic silyl halido cuprates consisting of the new tripodal silicon-based metalloligand [κ(3)N-Si(3,5-Me2pz)3Mo(CO)3](-) is presented (pz = pyrazolyl). This metalloligand is straightforwardly accessible by reacting the ambidentate ligand tris(3,5-dimethylpyrazolyl)silanide ({Si(3,5-Me2pz)3}(-)) with [Mo(CO)3(η(6)-toluene)]. The compound features a fac-coordinated tripodal chelating ligand and an outward pointing, "free" pyramidal silyl donor, which is easily accessible for a secondary coordination to other metal centers. Several bimetallic silyl halido cuprates of the general formula [CuX{μ-κ(1)Si:κ(3)N-Si(3,5-Me2pz)3Mo(CO)3}](-) (X = Cl, Br, I) have been synthesized. The electronic and structural properties of these complexes were probed in detail by X-ray diffraction analysis, electrospray mass spectrometry, infrared-induced multiphoton dissociation studies, cyclic voltammetry, spectroelectrochemistry, gas-phase photoelectron spectroscopy, as well as UV/Vis and fluorescence spectroscopy. The heterobimetallic complexes contain linear two-coordinate copper(I) entities with the shortest silicon-copper distances reported so far. Oxidation of the anionic complexes in methylene chloride and acetonitrile solutions at E(1/2)(0( = -0.60 and -0.44 V (vs. ferrocene/ferrocenium (Fc/Fc(+))), respectively, shows substantial reversibility. Based on various results obtained from different characterization methods, as well as density functional theory calculations, these oxidation events were attributed to the Mo(0)/Mo(I) redox couple., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The treatment of 2,2'-di(1,2-pyrazol-3-yl)-1,1'-binaphthyl with two equivalents of appropriate monovalent group 11 precursors in the presence of a base leads to a complete exchange of the pyrazole NH protons with M(+) cations. Structural characterisation of the copper(I) complex revealed a hexanuclear complex with a pelton-wheel-like arrangement of the binaphthyl unit. As indicated by their spectroscopic data, all three complexes are isostructural. The complexes show a complex fluorescence behaviour that can be partially related to the ligand system and also to the metal sites, as indicated by the position of the fluorescence peaks and their temperature dependence and lifetimes., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)