Activation of Dioxygen at a Lewis Acidic Nickel(II) Complex: Characterization of a Metastable Organoperoxide Complex

• Published in: Angewandte Chemie Vol. 129; no. 9; pp. 2347 - 2351
• Main Authors: Holze, Patrick, Corona, Teresa, Frank, Nicolas, Braun‐Cula, Beatrice, Herwig, Christian, Company, Anna, Limberg, Christian
• Format: Journal Article
• Language: English; German
• Published: Weinheim Wiley Subscription Services, Inc 20.02.2017
• Subjects: Absorption spectroscopy; Activation; Chemistry; Coordination compounds; Disauerstoff-Aktivierung; Enzymes; Formations; Hydrogen storage; Nickel; Oxidationen; Oxygen atoms; Oxygenasen; Peroxide; Peroxides; Spectroscopy; Synthesis
• ISSN: 0044-8249; 1521-3757
• DOI: 10.1002/ange.201609526

In metal‐mediated O2 activation, nickel(II) compounds hardly play a role, but recently it has been shown that enzymes can use nickel(II) for O2 activation. Now a low‐coordinate Lewis acidic nickel(II) complex has been synthesized that reacts with O2 to give a nickel(II) organoperoxide, as proposed for the enzymatic system. Its formation was studied further by UV/Vis absorption spectroscopy, leading to the observation of a short‐lived intermediate that proved to be reactive in both oxygen atom transfer and hydrogen ion reactions, while the peroxide efficiently transfers O atoms. Both for the enzyme and for the functional model, the key to O2 activation is proposed to represent a concomitant electron shift from the substrate/co‐ligand. Nickel(II) kann es auch: Über die Kooperation mit einem redoxaktiven Liganden kann Nickel(II) bereits bei tiefen Temperaturen O2 aktivieren, wie kürzlich auch für die Nickel‐abhängige Quercitinase vorgeschlagen wurde. Ausgehend von einem Nickel(II)‐Komplex und O2 konnte eine Nickel(II)‐Organoperoxo‐Einheit erzeugt werden (siehe den Strukturkern des kristallisierten metastabilen Peroxids).