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.

Chelate ligands containing at least one pyrazole group were treated with RuCl2(PPh3)3, RuHCl(CO)(PPh3)3 and RuH2(CO)(PPh3)3 to form ruthenium complexes bearing protic N–H groups in close proximity to the catalytically active ruthenium centre. In the case of the hydridoruthenium complex RuHCl(CO)(PPh3)3 the resulting complexes also contain abasic hydrido ligand. The combination of acidic and basic hydrogen species in one molecule and the arising two‐site reactivity was thoroughly investigated spectroscopically and by DFT calculations. Catalytic tests on the hydrogenation and transfer hydrogenation of acetophenone showed a general activity of these systems.

In combination with different aromatic N,N‐donors, iron acetate and octanoate are suitable catalyst precursors for the hydrosilylation of carbonyl compounds. Iron octanoate can be used to perform this catalytic transformation in cheap and non‐toxic petrol ether or heptane as the solvent and with versatile polymethylhydrosiloxane (PMHS) as the silane source. Investigation of the preformed catalyst (iron octanoate+N,N‐ligand+PMHS) by using Mössbauer spectroscopy suggests that the active species is a high‐spin iron(II) system.

Chiral ligands with the 1,1′‐binaphthyl unit as the backbone play an important role in enantioselective catalysis. In this paper we present the synthesis and characterization of three novel azole‐functionalized 1,1‐binaphthyl derivatives. These systems are accessible from commercially available starting materials in not more than four steps. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

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