Rhenium complexes clusters

Platinum nanoparticles, preparation, 12, 78 Platinum-nitrogen bonds, in platinacycles, 8, 508 Platinum-osmium carbonyl clusters, characteristics, 8, 420 Platinum-oxygen bonds, in platinacycles, 8, 505 Platinum particles, surface reactivity, 12, 542 Platinum-phosphorus bonds, in platinacycles, 8, 508 Platinum-rhenium carbonyl clusters, characteristics, 8, 420 Platinum(II)-ruthenium(II) binary complexes, preparation,... 

One of the stimuli for studying these complexes is their close relationship to the well-known Chevrel phases MMo Yg (Y = S, Se or Te). Accordingly, a noteworthy recent development is the discovery of octahedral rhenium-selenide clusters. The phase Re SegClj has been prepared by the high temperature reaction ( BOOK) of ReQj with mixtures of Re and Se. An X-ray crystal structure has shown the presence of the [RcgScg] core possessing Re—Re distances of 2.6 2.67 A. The presence of two terminal Re—Cl bonds tram to one another) inhibits interlayer linkages. ... 

In contrast to the synthetic accessibility of the above complexes using solution approaches, the synthesis of octahedral rhenium chalcogenide clusters requires the implementation of high temperature solid-state reactions, or the conversion of cluster-containing solids into soluble molecular species by the methods of cluster excision or dimensional reduction (see Section 7.2.2.1.8). While cluster excision has produced the mixed sulfide(selenide)-chloride clusters [Re6E4+ Clio 2 ] " ( = 1-3), the latter approach has led to the isolation of complexes with rhenium-chalcogenide cores [RegEgXg] - (E = S, Se X = C1, Br, I). 

C, Carbide, iron complex, 26 246 ruthenium cluster complexes, 26381-284 CHF3O3S, Methanesulfonic add, trifluoro-, iridium, manganese, and rhenium com-iriexes, 26 114,115,120 platinum complex, 26 126 CHOS2, Dithioaubonic add, 27 287 CH2> Methylene, osmium complex, 27 206 CH2O2, Formic add, rhenium complex, 26 112... 

Trinuclear rhenium-rhodium clusters 55 57 are formed from reaction of H2Re2(CO)g with Rh(CO)2Cp in refluxing hexane a similar thermolysis with the dimer Rh2(CO)2Cp 2 affords 55 and 56 as the main products, along with small amounts of the butterfly cluster 58. Complex 55 decomposes under relatively mild conditions to give fragmentation products whose... 

The synthesis and characterisation of the platininn-containii species (PPh3)HPt(/i-PPh2XM"CO)M(CO)4 (M = Cr, Mo, W) has been reported by Shao et al The range of rhenium-platinum clusters has been extended by the preparationof the complex [Re3Pt(/L(-H)3(CO)i4]. Osmium-rhodium complexes are also mentioned ... 

Besides the use of vanadium-based catalysts, a wide variety of other catalyst compositions were reported. A recent review focussed on FeSbO based catalysts promoted by appropriate additives as suitable for the ammoxidation of alkyl-substituted aromatics and hetero aromatic compounds. A unique preparation method of a fluid-bed catalyst is presented using nitric acid oxidation of antimony trioxide catalyzed with iron ions. The catalysts thus prepared have superior catalytic and physical properties. [78]. In addition, some unique compositions were reported by different research groups. For instance, new ammoxidation catalysts based on rhenium carbonyl cluster complexes containing antimony and bismuth ligands were reported by Adam et al. [79]. Single-site multifunctional catalysts based on [Cu RUj C ] nanocluster anchored to inner walls of mesoporous silica were also used in the ammoxidation of 3P [80]. 

Non-ionic thiourea derivatives have been used as ligands for metal complexes [63,64] as well as anionic thioureas and, in both cases, coordination in metal clusters has also been described [65,66]. Examples of mononuclear complexes of simple alkyl- or aryl-substituted thiourea monoanions, containing N,S-chelating ligands (Scheme 11), have been reported for rhodium(III) [67,68], iridium and many other transition metals, such as chromium(III), technetium(III), rhenium(V), aluminium, ruthenium, osmium, platinum [69] and palladium [70]. Many complexes with N,S-chelating monothioureas were prepared with two triphenylphosphines as substituents. 

This facile approach to the carbene chemistry of rhenium has not yet been investigated with technetium. Further reactions with the technetium cluster 44a have been performed in C6H6/HC1 to yield the compound [( 6H6)Tc(CO)3]+ (66) which previously had only been described for manganese and rhenium [81]. "Tc-NMR of the latter compound exhibits a resonance at -1983 ppm (relative to [Tc04]- ), and it therefore fits very well into the range proposed for Tc(I) complexes. 

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