Mixed-metal clusters trinuclear

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). 

The metal framework of trinuclear clusters capped by one or two bridging groups is more robust toward oxidation or reduction. The mixed-metal clusters [FeCo2(CO)9(/t-E)] (65) (E = S, Se, or PR) reduce in successive one-electron steps, first to a somewhat persistent anion radical [E = S, r,/2 = 60 seconds 142)) at mild potentials (E = S, = -0.24 V vs Ag/AgCl), and then to a very unstable dianion 142, 143). 

This section is dedicated to a description of the chemistries of trinithenium and triosmium clusters that do not contain hydrocarbon ligands. This section should be viewed as an addition to the chemistry described in sections 32.5 and 33 of COMC (1982) and section 12 of COMC (1995) as most of the main themes have been developed in the previous two decades. Overall, the interest in the cluster chemistry of ruthenium and osmium during the period 1994-2004 has tended to focus mainly on higher nuclearity and mixed metal clusters in order to enhance the developments in catalysis and bridge the gap between molecular clusters and nanoparricles. However, triruthenium and triosmium clusters continue to play a pivotal role in the chemistry of ruthenium and osmium. Both classes of clusters can be, and are, used extensively as precursors for the synthesis of higher nuclearity clusters as well as the formation of mono- and bimetallic complexes. No up-to-date review of the chemistry of either Ru3(CO)i2 or Os3(CO)i2 and their compounds is available, but several annual reviews of the chemistry of mthenium and osmium, which include the chemistry of the trinuclear clusters, are available. ... 

Figure 9.27 The structure of the GdCo2 cluster and its magnetic relaxation behavior [112], (Reprinted with permission from V. Chandrasekhar, et al Linear trinuclear mixed-metal Co — Gd — Co singlemolecule magnet [LzCoaGdJpSlOsl CHCL (LHs = (S)P[N(Me)NCH—C6H3-2-OH-3-OMe]3), Inorganic Chemistry, 46, 5140-5142, 2007. 2007 American Chemical Society.)...

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