Copper-dioxygen complexes and their roles in biomimetic oxidation reactions - Advances in Catalytic Activation of Dioxygen by Metal Complexes - page 98

Tolman and co-workers 99 have also synthesized a model system
which undergoes endogenous aromatic hydroxylation using an amine and a
pyridine ligand tethered to an arene. (Scheme 6) Unlike our XYL-H system,
oxygenation of copper(I)-complex forms a complex
instead of a peroxodicopper(II) complex. Upon decomposition, the
complex forms an unidentified copper(II) product
which yields both the hydroxylated and the original ligand in a ~2:1 ratio,
which corresponds to ~60% yield in monoxygenase activity.
Previous to this study, the Tolman group had also reported 100 on
complexes similar to the XYL-H model system which employ dinucleating
triazacyclononane moieties linked by m- or p -xylyl groups. These systems

form either complexes or
complexes, depending on conditions such as solvent, temperature, and
concentration. Based on this report, the complex
leads to arene hydroxylation, similar to the XYL-H system, whereas the
complex favors monooxygenation leading to N-

dealkylation.