A Ferromagnetically Coupled (S=1) Peroxodicopper(II) Complex1. Issue 6 (21st December 2014)

• Record Type: Journal Article
• Authors: Kindermann, Nicole; Bill, Eckhard; Dechert, Sebastian; Demeshko, Serhiy; Reijerse, Edward J.; Meyer, Franc
• Is Part Of: Angewandte Chemie international edition. Volume 54:Issue 6(2015)
• Page Start: 1738
• Page End: 1743
• Publication Date: 2014-12-21
• Subjects: bioinorganic chemistry -- copper -- EPR spectroscopy -- magnetic properties -- peroxo complexes; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201409709
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Copper enzymes play important roles in the binding and activation of dioxygen in biological systems. Key copper/dioxygen intermediates have been identified and studied in synthetic analogues of the metalloprotein active sites, including the μ‐η 2 :η 2 ‐peroxodicopper(II) motif relevant to type III dicopper proteins. Herein, we report the synthesis and characterization of a bioinspired dicopper system that forms a stable μ‐η 1 :η 1 ‐peroxo complex whose Cu‐O‐O‐Cu torsion is constrained to around 90° by ligand design. This results in sizeable ferromagnetic coupling between the copper(II) ions, which is detected by magnetic measurements and HF‐EPR spectroscopy. The new dicopper peroxo system is the first with a triplet ground state, and it represents a snapshot of the initial stages of O2 binding at type III dicopper sites. Abstract : Stuck in the middle with Cu : Rational ligand design results in a μ‐η 1 :η 1 ‐peroxo dicopper(II) complex whose Cu‐O‐O‐Cu torsion is constrained to around 90°, allowing a sizeable ferromagnetic coupling between the Cu II ions and a triplet ground state. The complex is a snapshot of the initial stages of O2 binding at biological type III dicopper sites (Cu red, O green).