Copper complex compounds binuclear

The reaction of dioxygen with laccase or ascorbate oxidase was reviewed in Section IX and in Messerschmidt et al. (74), where the possible binding modes of dioxygen to binuclear and trinuclear copper centers are discussed. A novel mode of dioxygen binding to a binuclear copper complex was found in a compound synthesized by Kitajima et al. (165). The complex contains peroxide in the mode, i.e., side-on between... 

There are many structural studies of copper coordination compounds with azide ligands, mainly of mononuclear and binuclear copper complexes but a few also of trinuclear copper complexes. A comprehensive... 

Alkylindium thiolate complexes readily react with copper dithiocarbamate compounds to yield binuclear complexes, according to Scheme No structural data is available for these mixed metal complexes however, they have been... 

Figure 7.48 Two cytochrome c oxidase Cua center model compounds (A) delocalized core with two i-l,3-(KN KO)-ureate bridges as reported in reference 165-and (B) a dithiolate-bridged mixed-valence binuclear copper ion complex as re in reference 166.

In a few instances, binuclear complexes have been reported in which the two copper atoms interact directly through a metal-metal bond. Two examples of such complexes are illustrated below [192, 193]. CV s run on the compound at left in both tetrahydrofuran and CH2CI2 indicated the presence of two separate electron-transfer steps that were quasi-reversible. 

The majority of cyanide-bridged dinuclear complexes described for the combination of metal ions belong to the biologically relevant class of Cu —Fe dimers. These compounds serve as models for the binuclear cyanide-inhibited site of cytochrome c oxidase, an enzyme that contains the heme-copper active site responsible for the O2 reduction chemistry (59). The lethal toxicity of cyanide was traced to its irreversible binding and inhibition of this active site in the enzyme (60). The biologically relevant aspects of these complexes were the subject of many reports (61,62). Our interest is in describing their crystal structure, which will be correlated to the magnetic properties in a later section. 

With an excess of [CuAN4](C104)2, the first binuclear compound with a possibly delocalized bond of Cu(I)/Cu(II) was also prepared [197]. A detailed template synthesis of the binuclear copper(II) complexes of macrobicyclic imBT ligand with a regular cavity and an imbistrpn ligand with an expanded cavity (Scheme 93) is described in Ref 198. 

Of course the EPR silent copper is crucial to the arguments summarized, and on this point, Hu, Chan and Brown have presented a serious challenge150,1S1). They examined the X-ray absorption edge spectra of oxidized and reduced cytochrome oxidase in the presence and absence of CN. Using model compounds, including plastocyanin (type I, blue Cu) and a binuclear Cu(II) complex along with other... 

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