Copper dioxygen adducts

In contrast to iron and cobalt, end-on superoxo-copper(II) species do not dominate the field of copper-oxygen chemistry. In 1 1 copper-dioxygen adducts, an alternative side-on, t 2 coordination mode is sometimes observed these [(L)Cu11 (t 2-(02 ")] or [(L)Cum-(ri2-(022 )] complexes are discussed below. Mononuclear copper-dioxygen complexes easily react with the second molecule of the Cu(I) complex, forming peroxo- or dioxo-bridged dinuclear species (Section 4.4). For sterically unhindered... 

Two-electron reduction of dioxygen into coordinated peroxide can be easily performed by two metal centers undergoing concomitant one-electron oxidations, as shown in Equation 4.4 (Section 4.2.2). A variety of transition metal ions (cobalt, nickel, iron, manganese, copper, etc.) can form dinuclear peroxides. These complexes differ in structure (cA-p-1,2-peroxides, trans- l- 1,2-peroxides, p-r 2 r 2-peroxides), in stability and subsequent reactivity modes, and in the protonation state of the peroxo ligands (Figure 4.3). In certain cases, dinuclear p-r 2 r 2-peroxides and bis-p-oxo diamond core complexes interconvert, as discussed below for copper-dioxygen adducts. 

Heme-copper/dioxygen adduct formation, properties, and reactivity 07ACR563. 

Cu(Mim )02] + and [Cu(Mim )02] + copper dioxygen adducts. The numbers are the lengths and their standard deviations in parenthesis for the important chemical bonds involved in decoherence. The values are averaged over few picoseconds of DFT-BOMD simulations. The first and second lines correspond to the singlet and triplet spin-states respectively. 

Figure 5.8 Analysis of the overlap contribution to the decoherence function within the [Cu(Mim )02] (left) and [Cu(Mim )02] (right) copper-dioxygen adducts. The full lines are the (real part) of the overlap term and the dotted...

Gorun and co-workers also reported on the synthesis of a room-temperature stable copper-dioxygen adduct, Cu 202(Tp )2 by replacing C-H bonds in the vicinity of the CU2O2 core with C-F bonds. The ligand, 3-trifluoromethyl-5-methyl-l-pyrazolyl borate is analogous to the... 

However, it is highly unlikely that the active oxygenation species is a discrete copper-dioxygen adduct in this system. In fact, the authors suggest that it is probably a Cu(n)-catalyzed autoxidation reaction that leads to the oxygenation of a methine position in the ligand. 

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