Copper complex compounds structure

Increased interest in the chemistry of ylides has produced X-ray structures for compounds 123 (R = OMe) (91T5277) and 138 (92H(34)1005), while possibilities of complex formation have led to structures for bidentate copper complex of 135 (94JCS(D)2651), monodentate copper complex of the 3-phenyltria-zolopyridine 139, monodentate (through N2) dinitrato ligand of 3-methyl-triazolopyridine 140 (99MI4), and dinitrato bidentate copper complex of... 

Using a deprotonated hydroxyiminoamide ligand, Kruger and co-workers33 structurally characterized a discrete copper(III) compound (6). The square-planar structure is retained even in solution. Absorption and redox properties of this complex were also investigated. 

The required long planar shape is more readily supplied by simple disazo structures such as Cl Direct Blue 1 (4.60). Copper complexes of such disazo compounds are important and are dealt with elsewhere (section 5.5.3). A widely used method of producing A—A type disazo dyes relies on treating J acid with phosgene (COCl2) to give the bis-coupling component carbonyl J acid (4.61). 

The only copper complexes of tridentate azo compounds are 1 1 structures, since copper(II) has a CN of 4. They can be prepared by the reaction of the azo compound with a copper(II) salt in an aqueous medium at 60 °C. The major application for copper-complex azo dyes is as direct or reactive dyes for the dyeing of cellulosic fibres. They are seldom developed for use on wool or nylon, although various orange and red 1 1 copper-complex azopyrazolones (5.42) were synthesised recently and evaluated on these fibres by application from a weakly acidic dyebath [24]. 

Recently, hf structure associated with the copper signal of cytochrome c oxidase has been reported by Frondsz et al.210 which used octave bandwidth S-band EPR spectroscopy (2-4 GHz). The observed structure has been attributed to copper hfs and to an additional magnetic interaction. Data obtained from powder simulation of the EPR spectra at 2.62 GHz and 3.78 GHz are collected in Table 12.2. In a subsequent paper Frondsz and Hyde211 have shown that in S-band EPR spectra of copper complexes in frozen solutions, improved spectral resolution can be achieved. This new technique, which allows a proper selection of the microwave frequency between 2 and 4 GHz, is therefore recommended for studying powder EPR spectra of these types of compounds. 

Of the other possible structures (95) of the condensation product, the Schiff s base (CXXX) is not resolvable, nor, because of the tautomeric nature of the guanidine system, is the four-membered ring compound (CXXXI). A compound of the improbable structure (CXXXII) should yield a copper complex, which the condensation products failed to do. 

Physical Measurements on Copper Complexes.—Detailed discussion of papers concerned purely with spectroscopic and magnetic data obtained for copper complexes is now covered by the Chemical Society Specialist Periodical Report Electronic Structure and Magnetism of Inorganic Compounds (ed. P. Day), Volumes 1 and 2, and will not be included here. However, three papers of some significance are cited below and other papers on this subject listed in Table 5. 

Hydridic copper complexes have been discussed in the literature for a very long time. Recently they have been shown to have a variety of interesting chemical and structural properties. Unfortunately, a good workable synthesis leading to stable isolated compounds does not currently exist in the literature. 

La2Cu04, Sr2Cu04. As we show in chapter 6, when a perovskite forms a composite or intergrowth with other structures, new compounds of interest in catalysis can be formed (such as in high-temperature superconducting copper oxides) and EM is used to determine the structures and properties of these complex compounds. The merits of using perovskites in steam reforming, membrane catalysis and fuel cells are discussed in chapter 6. 

This appeared unlikely for several reasons firstly, o-hydroxydiarylazo compounds form copper complexes in which the metal atom forms a part of a six-membered chelate ring and, secondly, interaction between the hydrogen atom in the 8-position of the naphthalene nucleus and the lone pair on the fl-nitrogen atom of the azo group would not favour a structure such as (51). 

Copper complex formation. Add a few drops of aqueous copper(n) sulphate solution to an aqueous solution of the amino acid. A deep blue coloration is obtained. The deep blue copper derivative may be isolated by boiling a solution of the amino acid with precipitated copper(n) hydroxide or with copper(n) carbonate, filtering and concentrating the solution. These blue complexes are coordination compounds of the structure ... 

The mechanism of the enantioselective 1,4-addition of Grignard reagents to a,j3-unsaturated carbonyl compounds promoted by copper complexes of chiral ferrocenyl diphosphines has been explored through kinetic, spectroscopic, and electrochemical analysis.86 On the basis of these studies, a structure of the active catalyst is proposed. The roles of the solvent, copper halide, and the Grignard reagent have been examined. 

A side-on p,-Tq2 Tq2-peroxo dicopper(II) complex. A very important development in copper-dioxygen chemistry occurred in 1989 with the report by Kitajima et al. [10,108] that another Cu202 species could be prepared and structurally characterized by using copper complexes with a substituted anionic tris(pyrazolyl)borate ligand. This intensely purple compound, Cu[HB(3,5-iPr2pz)3] 2(02) (5), was prepared either by reaction of Cu[HB(3,5-iPr2pz)3] (4) with 02 or by careful addition of aqueous hydrogen peroxide to the p-dihydroxo... 

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