Ruthenium mixed-metal clusters

STEPWISE SYNTHESES OF RUTHENIUM MIXED-METAL CLUSTER COMPLEXES... 

Stepwise Syntheses of Ruthenium Mixed-metal Cluster Complexes 357... 

Ruthenium mixed-metal clusters, 26 356 Ruthenium(II), p.-aqua-bis(p.-chloroace-tato)bis[(chloroacetato)(V-cyclo-oacta-1,5-diene)-, 26 256... 

MIXED-METAL CLUSTERS OF IRIDIUM WITH RUTHENIUM AND OSMIUM... 

Mixed-Metal Clusters of Iridium with Ruthenium and Osmium 207... 

Several synthetic methods are now available for the preparation of mixed-metal clusters.1 However, when particular clusters are desired, two main points of concern for their synthesis often remain the availability and price of the precursors, and the yield of the reaction. Mixed-metal clusters containing ruthenium have attracted considerable interest mainly because of the variety of structural and bonding types encountered, and of their potential for homogeneous and heterogeneous catalysis.2... 

MIXED-METAL CLUSTER COMPLEXES OF NICKEL WITH RUTHENIUM OR WITH OSMIUM... 

There are few reports of reactions between alkynes and trinuclear clusters of metals other than iron, ruthenium, or osmium. Some rhodium, platinum, and mixed-metal clusters undergo metal-metal bond rupture in reactions with alkynes (54-56), while in other cases the alkyne coordinates to the trinuclear unit without causing any major changes in framework geometry (56-59), as illustrated in Eq. (3). 

Mixed metal clusters (clusters containing two different metals) have considerable potential for mechanistic studies. Three separate studies on iron mthenium clusters show the possibilities. Reactions of FeRu2(CO)i2 and Fe2Ru(CO)i2 in comparison to Fe3(CO)i2 and Ru3(CO)i2 show a very interesting activation of the iron center towards CO dissociation by ruthenium centers in the mixed metal-cluster system. Such an activation of the iron center by ruthenium has also been demonstrated for (/r-H)FeRu2(/(r-COMe)(CO)io. The presence of different metal centers for H2FeRu3(CO)i2 allowed unusually detailed interpretation of the isomerization, substitution, and CO exchange reactions. ... 

It seems that one of the future developments in cluster chemistry lies in the production of nanosized particles (1 nm = 10 A) with well defined stoichiometries, which can be used as catalysts or as catalyst precursors. In this context, high nuclearity mixed-metal clusters are particularly useful because two or more metal atoms with different chemical properties can be combined in the same unit. The Cambridge group has spent the last few years designing rational synthetic routes to mixed-metal high nuclearity clusters of ruthenium and osmium with the coinage elements, which produce cluster cores of up to one nanometer in size. ... 

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