Copper complexes hexanuclear

It is possible that a heteronuclear molecular cluster can offer a suitable explanation of these latter results a greater variety of heteronuclear molecular clusters with different transition metals are known. However most of them possess three or four metal atoms and do not represent the best models for very small particles of alloys. Examples of heteronuclear clusters with more than four metal atoms are rare. An interesting example is given by the hexanuclear iridium-copper complex syn-thetized by Bruce et al [135] of formula Cu4lr2(PPh3)2 ( C = C-Ph)g. In this cluster the six metal atoms form a distorted octahedron in which two PhaP-Ir moieties are mutually trans four — C = C-Ph units are only a bonded to each Ir atom and four — C = C-Ph units (one from each Ir) form tt linkages to each of the four equatorial copper atoms (Figure 25). 

Ford and Vogler reported the photophysical properties of a hexanuclear copper(I) thiolate cluster [Cu (mtc) ] (13) and the related silver(I) complexes [86]. The copper complex shows an intense emission band at 706 nm (Xo = 0.99 ps) and 767 nm (Xq = 14.0 ps) in the solid state at 294 and 77 K, respectively. The emissive state has been suggested to derive from an admixture of LMCT [thiolate Cu ] and metal-centered d-s character. 

Endicott, J. F. Ramasami, T Tamilarasan, R. Lessard, R. B. Brubaker, G. R. Structuie and Reactivity of the Metal-Centered Transition Metal Excited States, Coord. Chem. Revs. 1987,77,1. Ferraudi, G. Thotochemical Properties of Copper Complexes, Coord. Chem. Revs. 1981,36,45. Ford, P. C. Vogler, A. Photochemical and Photophysical Properties of Tetranuclear and Hexanuclear Clusters of Metals with and Electronic Configurations, Acc. Chem. Res. 1993,26,220. 

The hexanuclear platinum-copper complex Pt2Cu4(C6F5)4(C=C Bu)4(acetone)2] (320) and the polynuclear derivative [PtCu2(C6F5)2(C=CPh)2] c (321), which... 

Addition of alcohols to dimeric copper carboxylates can also produce hexanuclear complexes. Dissolving copper(II) acetate in 2-diethylaminoethanol, followed by addition of ether, produces... 

Karlin and co-workers have designed several trinucleating ligands " " for study in Cu 3/02 reactivity studies. For example, when a tricopper(I) complex of MES (Structure (a), Figure 17) is oxygenated, hydroxylation of the mesitylene ligand occurs. " A hexanuclear copper(II) product... 

The hexanuclear complexes of Cu(II) and Ni(II) with polysiloxanolate ligands display different magnetic behavior [20]. The Cu(II) complex shows a ferromagnetic coupling with a ground state of S=3 [113], while in the case of the Ni(II) complex the ground state has S=0 [114]. Analysis of the crystal structures reveals a similar structure of the complex, but in the case of the nickel atom a chloride anion is placed in the center of the channel in order to complete the octahedral coordination whilst the copper atom has square pyramidal coordination (see Fig. 11). 

Fig. 11 View of the hexanuclear Cu(II) polysiloxanolate complex (left) and the corresponding Ni(II) complex with a chloride anion in the middle of the channel (right). The carbon, copper, nickel, oxygen, chlorine, silicon, and hydrogen atoms are represented by spheres of different shades of gray, from dark to bright, respectively...

Neutron diffraction structure analysis of a hexanuclear copper hydrido complex, H6Cu6[P(p-tolyl)3]6 An unex- 27. pected finding. J. Am. Chem. Soc. 1989, 111. 3472-3473. 

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