Decanuclear cluster

The thermolysis of 4 with Ru3(CO)12 3 in bis(2-methoxyethyl)ether under reflux for 3 h affords the decanuclear cluster [RuioC(CO)24]2 218 in 81% yield (Scheme 36).124 The same cluster has also been isolated from the thermolysis of 3 with mesitylene.95 The structure of 218 has been established by single crystal X-ray diffraction, which shows that the metal skeleton consists of a tetra-capped octahedron decorated with terminal carbonyl ligands. Cluster 218 reacts with CO in dichloromethane under ambient conditions to regenerate 4 and 3 in quantitative yield.109 The decanuclear cluster 218 also undergoes a reversible reaction with two equivalents of iodine to afford [RuioC(CO)24I] 219.109 At higher temperatures further reaction occurs with iodine to produce a species tentatively characterized as the hexamer [Ru6C(CO)i6I2] 220. 

Scheme 15 shows the geometry of the only decanuclear cluster, which has been electrochemically investigated. 

The decanuclear cluster [OsioC(CO)24] can be prepared in 65% yield by vacuum pyrolysis of Os3(CO)ii(NC5H5). Its structure is based on a tetrahedron formed by three layers of close-packed Os atoms in the sequence 1 3 6. An alternative view of this cluster is as a tetracapped octahedron with the carbide atom located inside the octahedral cavity. Reaction of [OsioC(CO)24] with iodine initially affords the monoanion [OsioC(CO)24l] , and subsequently, the neutral cluster [OsioC(00)24X2] (Scheme 24). In [OsioC(CO)24l] one Os-Os bond of a capping atom has cleaved with the concomitant insertion of an I atom into the metal-metal... 

Figure 3.2 Core structures of nonanuclear (a, b, c), decanuclear (d) and undecanuclear (e) gold clusters.

The thermolysis of [RufiC(CO)i6]2 4 in tetraglyme at 210-230°C for 80 h affords the decanuclear dicarbide cluster [RukjC CO ]2- 216 in 35% yield (Scheme 35).121,122 The structure has been established by single crystal X-ray diffraction, which reveals that the metal core comprises two... 

The neutral decanuclear complex [Mn°(tptz)(H20)]2[Mn (tptz) (MeOH)2l4[W (CN)g]4 (152) exhibits a structure in which three cyanide Mu2W2 squares are connected by shared W(V) comers [Fig. 54(a)]. Another view of this cluster [Fig. 54(Z>)] reveals that the peripheral squares are quite distorted and adopt a butterfly conformation. The overall shape of the cluster core resembles two boats fused at the Mn(II) centers. 

For nitrido clusters, open butterfly structures with a RU4 core are observed in (38) and the precursor molecules (35) or (37), where one nitride or isocyanate ligand bridges the open wings of the butterfly. RusN cores, exemplified by [RusN(CO)i4] (41), are of a similar square pyramidal arrangement as RusC clusters. The nitrido atom in the former is displaced out of the basal plane by as much as 0.21 A (i.e. about twice as much as the carbon atom in (30)) making the transition to a distorted octahedron. The decanuclear complex... 

Figure 2.10.17 Molecular structure of the decanuclear organotinoxo cluster 81...

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