Di- and tri-nuclear complexes

Redox Properties of Oxo Bridged Di- and Tri-nuclear Complexes of Heavy Transition Elements Stability of Mixed Valence State. 

Redox propcTties of some oxo-bridged di- and tri-nuclear complexes of the second and third transition elements. Re, Ru, Os, and Mo, are discussed with special attention to stability of the mixed-valence states. These complexes display multi-step one-election transfer processes and give fairly stable mixed-valence oxidation state. Stability of the mixed-valence states is discussed in terms of qualitative molecular orbital schemes based on dJt (metal) - prt (bridged oxygen) interactions. 

Figure 1. Schematic drawing of the basic structures of the di- and tri-nuclear complexes discussed in this paper.

Figure 2. Simplified qualitative molecular orbital description of the n-type interaction of oxide-bridged di- and tri-nuclear complexes (only the relevant orbitals are shown), (i) Linear oxo-bridged dirmdcar complexes, (ii) Bent oxo-bridged dinuclear complexes (with additional caiboxylate bridges), (iii) Oxo-centered tiinuclear complexes, (iv) a- and n-type interaction of edge-shared dinuclear complexes.

Ni(salen)SnCl4 R ] (R = Ph, Me n = 1, 2) (324)Similar complexes were also reported with PbCl2Ph2 and TlCl2Ph, SbXs (X = C1, Br) and Mn(CO)3X. Di- and tri-nuclear complexes of nickel(II) were obtained by reacting Ni(N03)2 hydrate with Schiff b e complexes of nickel(Il). The donor-acceptor molecular complexes between 1,3,5-trinitrobenzene and bidentate Schiff base complexes were also investigated. ... 

Qualitative observations have been made on Ni exchange with mercaptoethyl-amine (LLH) complexes [Ni(LL)2] or (Pd(LL)-2], and with similar di- and tri-nuclear complexes containing nickel(n) and/or palladium(ii). ... 

The X -ray determined structure of [Mn2(M-CF2)2(CO)8] is reported. Photoreactions of [Re2(C0)j g] with ethylene, styrene or isoprene give various di- and tri- nuclear complexes Including structurally characterised [Re3 /i-o n2-C5H-j)(CO)3 3]. Allene and [Mn2(CO)3ol form three dlnuclear species including [Mn2([Pg.165]

The synthesis and structural characterization of luminescent di- and tri-nuclear organopalla-dium complexes with rigid conjugated alkynyl-aryl bridges and preliminary experiments on the formation of the first generation metallodendrimer using the trinuclear complex as the backbone were reported.102... 

Many types of ligand have been designed or are known to favour the formation of di- and tri-nuclear nickel complexes. This field of coordination chemistry has recently been extensively reviewed.2590,2591 For a specific discussion of the magnetic properties of dinuclear nickel(II) complexes, see Section 50.5.10. 

Laine M et al (2009) Base moiety selectivity in cleavage of short oligoribonucleotides by di- and tri-nuclear Zn(II) complexes of azacrown-derived ligands. Org Biomol Chem 7 ... 

Table 5 Effects of bifunctional DMA binding of mono-, di- and tri-nuclear platinum complexes ...

Table 4 Di- and Tri-nuclear Dinitrogen-bridged Complexes of Rhenium(I) with Transition Metals... 

V,)V -Ethylenebis(salicylideneiminato)nickel(II), [Ni(salen)] (319), behaves as a bidentate ligand through its oxygen atoms towards a variety of transition and non-transition metals, affording interesting and unusual di- and tri-nuclear heterometal complexes For... 

Reductive coupling of two organic ligands from a pair of metal complexes has already been reviewed [94], More recently, kinetic studies on reductive elimination from di- and tri-nuclear metal complexes have been reported [95,96], For C-H reductive elimination reactions from dipalladium complexes with the A-frame structure [Pd2R2(At-H)( -dppm)2]+, a concerted mechanism involving a W-shaped intermediate has been proposed (Scheme 9.38) [95a],... 

Relevant reviews which have appeared coverphosphinoboranes, classical and non-classical methylene dicoordinate boron, di- and tri-nuclear metal complexes of diboraheterocycles, and more generally the use of boron compounds in neutron capture therapy of... 

The use ofpoly-NHC allows to easily obtain polymetallic systems mainly di-iii-ii and tri-nuclear complexes have been reported, although some examples of higher nuclearity species have been also presented." ... 

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