Synthesis, Structure, and Greatly Improved Reversible O2 Binding in a Structurally Modulated μ‐η2:η2‐Peroxodicopper( II ) Complex with Room‐Temperature Stability

Facile O2 release from an oxyhemocyanin model has been achieved for the first time, with the new room-temperature-stable μ-η2:η2-peroxodicopper complex [Cu2O2(L2)]2+ (1). X-ray structural and spectroscopic studies on 1 show that elongation of the CuO bonds, induced by the bridgehead methyl groups of L2, is responsible for the ease of O2 release. CO/O2 binding by 1, monitored by UV/Vis spectroscopy (see picture), is completely reversible.