Multinuclear pyrazolate-based copper complexes inspired by the Cu_tnZ-site of N2O-reductase

Enzymes with multicopper active sites play important roles in many biological processes. Recently a novel multinuclear copper site was discovered in N2O-Reductase and its exact structure and mechanism has been much discussed since then. The so called CuZ center contains a unique tetranuclear Cu4S2-Cluster, which is coordinated by seven histidine residues. Until now no synthetic model complex could be isolated that emulates the Cu4S2 core of the active site. In this thesis a new strategy towards such model systems is introduced. To mimic the nitrogen-rich environment of the copper ions, pyrazolate-based ligand scaffolds with chelating N-donor side arms are employed. The resulting binuclear metal complexes were isolated and fully characterized. Additionally the reactivity of these binuclear building blocks towards various sulfur-containing coligands and sulfur-transfer reagents was investigated.