Synthesis and Structure of the Cluster Ion Pair {Ru<sub>3</sub>(CO)<sub>9</sub>[μ-P(NPr<sup>i</sup><sub>2</sub>)<sub>2</sub>]<sub>3</sub>}{Ru<sub>6</sub>(CO)<sub>15</sub>(μ<sub>6</sub>-C)[μ-P(NPr<sup>i</sup><sub>2</sub>)<sub>2</sub>]}. A Theoretical Overview of M<sub>3</sub>(μ-PR<sub>2</sub>)<sub>3</sub> Frameworks
收藏资源简介：
The compound {Ru3(CO)9[μ-P(NPri2)2]3}{Ru6(CO)15(μ6-C)[μ-P(NPri2)2]} (1), obtained via the addition of PCl(NPri2)2 to K2[Ru4(CO)13], crystallizes in the monoclinic space group P21/c with a = 15.537(8) Å, b = 36.151(16) Å, c = 19.407(5) Å, β = 91.14(2)°, Z = 4, and R = 0.069 for 8006 observed reflections. The unit cell is unusual in that it contains both a typical octahedral Ru6 cluster anion (1a), featuring an encapsulated carbide, and a symmetrical phosphido bridge, in addition to a 50-electron trinuclear cluster cation {Ru3(CO)9[μ-P(NPri2)2]3}+ (1c). The latter, with approximate D3h symmetry, exhibits long Ru−Ru distances (≥3.15 Å). Among the family of clusters with M3(μ-PR2)3 cores and different numbers of both electrons (TEC) and terminal ligands (LxLyLz), 1c is unique in that it is a 333 stereotype with 50 valence electrons. MO calculations permit us to predict the existence of redox congeners of 1c clusters and related 48e Re3 clusters. This work also presents a summary of the relationships between the electronic and the geometric structures for all known M3LxLyLz(μ-PR2)3 species. The basic stereochemical features are influenced by the total-electron count and, hence, by the degree of M−M bonding, as well as the remarkable flexibility of the phosphido bridging ligands. The μ-PR2 ligands need not necessarily lie in the M3 plane, and a wide range of M−P−M angles (as small as 72° or as large as 133°) have been observed.
