Reaction of H2FeRu3(CO)13 with tertiary phosphines and phosphites. Influence of ligand size and basicity on substitution site preference. Crystal and molecular structure of H2FeRu3(CO)12(PMe2Ph)

Abstract

Die Reaktion des FeRu‐Clusters (I) mit einer Reihe von tert. Phosphinen und Phosphiten L führt zu den Mono‐ und Disubstitutionsprodukten (II).

Reaction of the heterometallic cluster Os3Ru(μ-H)2(CO)13 with diphenylphosphine: phosphido-bridged tetrahedral and butterfly clusters

“…This leaves the most upfield resonance at À21.59 ppm assignable to H (13), which bridges an Os-Os edge. This is also consistent with earlier observations that the bridging hydride resonance in tetranuclear clusters is shifted increasingly upfield along the series Ru-Ru, Ru-Os and Os-Os [14]. The NMR assignments for 2 are thus as depicted in Fig.…”

Reaction of the heteronuclear cluster RuOs3(μ-H)2(CO)13 with toluene

“…We have assumed that these isomers differ only in the positions of the hydride ligands. Based on previous observations that the chemical shift for a metal hydride bridging an Os-Os edge would lie in a higher field than that bridging an Os-Ru edge [9], the tentative structures and 1 H NMR assignments are as given in Fig. 4.…”

The Aromatization of C5 Rings on a Heteronuclear Cluster

“…The identities of the species giving rise to the other two sets of resonances are uncertain, but there was an absence of crosspeaks involving these resonances, and the chemical shift ranges indicated that these hydrides may be bridging Os-Os bonds. [16] As already mentioned above, besides 2f, the reaction with trimethyl(2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl)silane also afforded RuOs 3 (µ-H) 3 (CO) 9 (µ-CO)(η 5 -C 5 Me 4 SiMe 3 ) (4), which has also been completely characterized, also by a single-crystal X-ray diffraction analysis; the ORTEP plot together with selected bond parameters is shown in Figure The silicon atom of the C 5 Me 4 SiMe 3 ligand is displaced by 9°, while the four methyl groups are displaced at an average of 5°, out of the plane of the central carbon ring. These indicate that the replacement of a carbonyl ligand with two bridging hydrides enabled the cyclopentadienyl ring to coordinate to the metal tetrahedron with less steric strain, and may explain why the SiMe 3 group was retained, unlike in 2f.…”