The work in this dissertation focuses on dinuclear copper-dioxygen complexes and their reactivity in intramolecular ligand hydroxylations. Recent findings suggest both µ-eta²:eta²-peroxido and bis(µ-oxido) copper complexes to play an important role in aromatic hydroxylation processes. The selective hydroxylation reactions are of great synthetic interest and model enzymatic activity. In this work the formation of bis(µ-oxido) intermediates in the process of aromatic hydroxylation reactions was investigated using low temperature stopped-flow UV-Vis spectroscopy. DFT calculations were used to obtain further insight into the mechanism. For these purposes the ligand PPN (2-(diethylaminoethyl)-6-phenylpyridine) known from literature and the new ligand BDED (N -benzylidene-N,N-diethylethylendiamine) were used as copper(I) complex. Both exhibit very similar reaction behavior towards molecular oxygen. A new synthetic application for selective aromatic hydroxylations was established with the ligand BDED and tested with several ligand variations in good yields.Using the similar, but aliphatic ligand DPDen (N -(2,2-dimethylpropylidene)-N,N-diethylethylendiamine) it was possible to show that the selective hydroxylation worked with aliphatic ligands as well. Formation and decay of the bis(µ-oxido) copper complex was investigated using low temperature stopped-flow techniques and allowed detailed kinetic analysis. The ligand was varied to obtain several selective hydroxylated aldehydes. The selectivity was demonstrated, e.g. adamantane was hydroxylated at the less reactive secondary carbon position. As well as the selective aromatic hydroxylation, this is a new synthetic application for preparing selective hydroxylated compounds.
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