Transition metals multinuclear complexes

The spectroscopy of multinuclear magnetic resonance in solution is one of the most important analytical methods in structural studies of transition metal hydride complexes. Among different nuclei, the proton plays the main role because H NMR provides a direct information about spectral properties of the hydride ligands. In addition the proton, being a non-quadrupolar and long-relaxing nucleus, gives rise to well-resolved NMR spectra which are very... 

Byabartta, P. (2007) Gold(l)-gold(III)-4,4 -bpy-phosphrne complexes synthesis and multinuclear NMR study. Transition Metal Chemistry, 32, 314. 

In contrast to the vast number of mono- and multinuclear binary carbonyl complexes of the transition metals, no isolable binary carbonyls of titanium, zirconium, or hafnium have been reported. 

The reaction of bis(silanethiolato) complexes of group 10 metals with transition metal complexes gives the corresponding multinuclear complexes accompanied by the elimination of the silyl chloride (Scheme 14).117,118... 

Chiari, B., Hatfield, W. E., Piovesana, O., Tarantelli, T., ter Haar, L. W. and Zanazzi, P. F. (1983). Exchange interaction in multinuclear transition-metal complexes 3. Synthesis, X-ray structure and magnetic properties of Cu2L(CH3COO)2 2CH3OH (L2 = anion of... 

The discussion of the structural chemistry of multinuclear cyanide-bridged complexes is concluded by considering two related families of compounds, the architecture of which are based on a face-centered cubic (fee) arrangement of transition metal ions. 

The heavier transition metal elements also form multinuclear ammine complexes, many with mixed oxidation states, for example, [Rn302(NH3)i4] + ( mtheninmred ) (48), [RU2(/aCl)3(NH3)6]2+ (49), [0S3(/xN)2(NH3)8(H20)6] + (50),... 

A large number of boratabenzene transition-metal complexes have been described. For instance, the multinuclear complex (141) has been obtained through the original Herberich route from cobaltocene with FcBBr2 (equation 37). Notably, a rhodium complex has recently been reported to be useful in C-H activation catalysis. ... 

In multinuclear complexes, NO can act as a bridging ligand, bridging two (63) or three metal atoms (64). NO has one electron more than CO, therefore the atomic number of the metal centers of NO complexes are lower than in similar CO complexes see Carbonyl Complexes of the Transition Metals), for example, Ni(CO)4, Co(CO)3NO, Fe(CO)2(NO)2, Mn(CO)(NO)3, and Cr(NO)4. For more information on nitrosyl complexes, see Reference 87. 

Condensation of organosilanols with transition metal halides is well established [3], but comparable reactions of metallo-silanols, which should provide a convenient entrance into the field of siloxy-bridged multinuclear complexes, has not been realized. In this context we have carried out the reaction of ferrio- and tungsten-silanols L,M-SiMe20H (L M = Cp(OC)2Fe (1) CsR5(OC)2(Me3P)W, R = H (5a), Me(5b)) with the electron deficient metal halides CpnMCh (w = 2, M = Ti, Zr n = 1, M = Ti). 

A comprehensive report of complexation between hydrophosphoranes and transition metal species includes (98) and (99) with [Rh(CO)2Cl]2 and (100) with [Rh(CO)2Cl], PdCl2(COD) or PtCl2(COD). All the products were characterised by laser-desorption MS, IR, multinuclear NMR and photoelectron spectroscopy. A correlation between Lewis basicity and coordination activity... 

Apart from some Weakley-type complexes (Table 22), there has been little systematic investigation of lanthanide-molybdate complexes. Multinuclear NMR studies of solutions of the well-established dodecamolybdates [MIVMo12042]8- (M = Ce, U), with a range of di- and trivalent transition-metal and lanthanide cations, show the formation of complexes incorporating two metal cations. In most cases these complexes are labile on the NMR timescale.368-370... 

H. Nishihara, Redox-based functionalities of multinuclear metal complex systems in A. S. Abd-El-Aziz and I. Manners (Eds.), Frontiers in Transition Metal-Containing Polymers, Wiley, Chichester, 2007. 

The aromatic moiety in phenylboranes and phenylb-orates may serve as a 6-electron tt donor ligand to transition-metal complexes. Half-sandwich complexes of chromium, Mes2[B( -Mes)Cr(CO)3] (56), MesB[jj -MesCr(CO)3]2 (57), and B[ -MesCr(CO)3]3 (58), containing trimesitylborane as a ligand have been prepared and structurally characterized. The Cr(CO)3 moieties interact weakly in the multinuclear systems (57) and (58) as shown by... 

The first example of a transition metal complex containing a y-tbp lO-P-4 phosphorus centre (120) results from the reaction of (118) with (119). X-ray crystallography reveals that all four ADPO units have y-tbp phosphorus centres and multinuclear n.m.r. in solution is consistent with this structure. ... 

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