Dinuclear Copper Carboxylates

Copper Carboxylate Complexes. The structural literature on copper(n) carboxylate complexes prior to 1971 is extorsive a recent report on anti-ferromagnetism in dinuclear copper carboxylates makes reference to nearly forty relevant crystallographic papers a 1967 review of metal-peptide... 

Figure 28.7 (a) Dinuclear structure of copper(II) acetate, and (b) spin singlet (25 +1 = 1) and spin triplet (25 +1=3) energy levels in dinuclear Cu carboxylates. 

The simplest complexes exhibiting columnar mesophases are the dinuclear metal carboxylates [M2(02CR)4], derived from simple alkanoic acids which have been synthesized with a range of metals [156]. Early work concentrated upon copper(II) carboxylates, with X-ray studies confirming the phases as hexagonal columnar... 

Octahedral co-ordination exists in [ 0(013803)2(1120)4] the four H2O oxygens bind in a square-planar arrangement (Cu—O = 1.97 A), whilst two oxygens (CH2SO3) bind in axial positions (Cu—O = 2.38 A). A kinetic study of the formation of a dinuclear complex between copper(ii) and a- or -cyclodextrin in alkaline solution shows the presence of Cu(OH)2Cu or Cu(OHXO)Cu ion bridges. A redetermination of the structure of Cu(EtCOO)2, -pic shows it to be dinuclear with carboxyl bridges and a Cu—Cu bond = 2.63 A (IIS). " The effect of 11 inert solvents on the... 

The dinuclear metal carboxylates M2(02CR)4 represent an important class of transition-metal complexes with respect to the study of structure and metal-metal interactions. Several new chain compounds of dinuclear metal carboxylates have been isolated and some of them show interesting gas-adsorption properties, giving a new aspect of chain complexes. Takamizawa and coworkers [149] presented evidence for a thermodynamic correlation between the phase transition and gas adsorption for a copper complex which was constructed by van der Waals interactions among chain-building blocks. 

J. Chem. Soc. Dalton 1972,428. dinuclear copper(II) carboxylate complexes. 

In marked contrast, l,5-bis(2-carboxyphenyl)-3-cyanoformazan reacted with copper(II) acetate in methanol to give a complex containing water which could not be removed by conventional physical methods. Further, the product was not converted into an anionic complex on treatment with potassium acetate. The clear implication of this is that one carboxyl group is not coordinated to the copper ion and structure (183) is preferred to (184) proposed earlier.129 It is, of course, possible that the complex has a dinuclear, oxygen-bridged structure of the type proposed for the... 

Dinuclear Species with Quadruple Bonds. Molybdenum carbonyl reacts readily with carboxylic acids to give yellow crystalline compounds Mo2(OOCR)4 which are thermally extremely stable. They have the copper... 

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