The synthesis of a new bioinspired dinucleating ligand scaffold based on a bridging pyrazolate with appended bis[2-(1-methylimidazolyl)methyl]aminomethyl chelate arms is reported. This ligand forms very stable copper complexes, and a series of different species is present in solution depending on the pH. Interconversions between these solution species are tracked and characterized spectroscopically, and X-ray crystallographic structures of three distinct complexes that correspond to the species present in solution from acidic to basic pH have been determined. Overall, this provides a comprehensive picture of the copper coordination chemistry of the new ligand system. Alterations in the protonation state are accompanied by changes in nuclearity and pyrazolate binding, which cause pronounced changes in color and magnetic properties. Antiferromagnetic coupling between the copper(II) ions is switched on or off depending on the pyrazole binding mode.

Polyols, which can be obtained readily from bio-feedstock, are converted efficiently into their corresponding cyclic carbonates by using a Wacker-type Pd/Mn catalyst system. A fine tuned redox cascade is essential in ensuring a high productivity of the Pd catalyst in the oxidative carbonylation reaction. Turnover numbers up to 784 mol_product/mol_palladium were achieved

During the hydrogenation of oximes, the temporary protection of the nitrogen moiety by a hydroxyl group promises to provide access to a highly selective synthetic route to primary amines. We will show that the reaction, however, proceeds via the more general network of imine and Schiff base chemistry. By choosing the right catalyst and conditions, specific pathways can be selected enabling us to steer the route from a pool of intermediate compounds to either primary or secondary amines. Thus, nickel catalysts provide high selectivity towards primary amines albeit at a moderate activity, while noble metal catalysts show good selectivity towards secondary amines, as well as high activity. Detailed analysis of the reaction sequence over Ni/SiO₂ provides insight into the pathways and provides understanding for the tools to obtain outstanding selectivities in the hydrogenation of oximes and other amine precursors

A highly preorganized bioinspired dicopper complex with imidazole ligation catalyzes the selective benzylic para-C-H activation of 2,4,6-trimethylphenol under aerobic conditions, yielding either the stilbenequinone or 4-methoxymethyl-2,6-dimethylphenol depending on the solvent used.

Bioinspired dual activation: Dual activation within the bimetallic pocket of a bioinspired dicopper(II) complex suitably places two phenolato substrates for preferred ortho-ortho coupling. Spectroscopic data and the molecular structure of a unique Cu(6) complex isolated from the reaction mixture reveal a novel terphenolato ligand and provide a clue about the activation mechanism (see picture).