Ru3 i

In general, sources of metal cluster fragments, such as Ru3(CO)io(NCMe)2 or Ru3(/i-dppm)(CO)io react readily with 1,3-diynes or poly-ynes initially to give alkyne complexes, which readily undergo further reactions as a result of activation by the cluster core. 

Like other peroxides, also dioxetanes are sensitive to the presence of metal ions and their complexes, which catalyze the decomposition of the dioxetane molecule. In most cases, this decomposition is dark, i.e. no chemiluminesce is generated in such a catalytic cleavage42. An informative exception, for instance, constitutes the chemiluminescent decomposition of the dioxetane 19 in Scheme 13, initiated by the ruthenium complex Ru(bipy)3Cl243. It has been shown that this chemiexcitation derives from the valence change of the ruthenium ion in the process Ru3+ I e — Ru2+, for which the efficiency of the excited-state generation may be as much as 40%44. Hence, when the radical anion of the carbonyl cleavage fragment from the dioxetane and the Ru3+ ion are formed in... 

To date only one such cluster has been reported. The tetranuclear cluster 33 is unstable in solution and over a period of several days eliminates the elements of Pt(COD)2, giving the Pt bridged cluster Pt[Ru3(/i-H)(ji4- 72-C=CtBu)(CO)9]2 (75) in reasonable yields (40-50%) (152). The C2 metal core (Fig. 15) is chiral, and a variable-temperature 13C NMR study showed that the cluster undergoes enantiomerization, with AG 66 = 57 kJ mol-1. The enantiomerization presumably proceeds via an intermediate or transition state with a planar coordination at the Pt atom. 

A related cationic cluster [Ru3(/i-H)(/i3-ampy)(/r,77 77 -PhG GHPh)(GO)8][BF4] is a catalyst precursor for homogeneous hydrogenation of diphenylacetylene to cis- and /ra r-stilbene under very mild conditions, 333 K and less than 1 atm hydrogen. Reactivity, spectroscopic, and kinetic studies suggest that the active catalyst is a cationic trimetallic cluster." ... 

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