Studies of the synthesis, structure, and reactivity of a tetranuclear mixed-metal imido cluster, (η⁵-C₅H₅)WRu₃(CO)₉(µ-NPh)(CCPh)

Abstract

The title complex (II~-C~H~)WRU,(CO),(~-NP~)(CZCP~), containing a bridging imido ligand and a p4-V2-acetylide ligand, has been prepared by means of the condensation between ( T ~~-C ~H ~) W ( C O ) ~C = C P ~ and Ru~(CO)&~-NP~), and its reactions with dihydrogen and disubstituted alkyne ligands are presented; the products have been fully characterized by spectroscopic methods and X-ray diffraction studies for two complexes.

Synthesis and Structural Characterization of [Ir4(mu-CO)(CO)7{mu4-eta3-Ph2PC(H)C(Ph)PCBu t}(mu-PPh2)]: Alkyne-Phosphaalkyne Coupling and Formation of a Novel 2-phosphabutadienylphosphine Ligand

“…We recently reported that [Ir4(µ-H)(CO)9(Ph2PC≡CPh)(µ-PPh2)] 1 containing a terminally bound diphenylphosphinoacetylene undergoes a facile rearrangement into [Ir4(µ-CO)(CO)7(µ3-η 2 -HCCPh)(µ-PPh2)2] 4 which was proposed to occur via CO loss, P-Csp bond cleavage and hydride migration to the α-carbon of the acetylide fragment 7 . Cluster coordinated acetylides have been shown to undergo nucleophilic attack of alkynes at the α-carbon 8,9 and, in an attempt to trap the proposed hydrido-acetylido intermediate in the transformation of 1 into 4, this reaction was carried out in the presence of P≡CBu t . We report herein the first example of a phosphaalkyne-alkyne coupling reaction in the coordination sphere of a cluster compound, and describe the synthesis and characterization of [Ir4(µ-CO)(CO)7{µ4-η 3 -Ph2PC(H) C(Ph)PCBu t }(µ-PPh2)] 2, which contains the 2-phosphabutadienylphosphine chain.…”

Cluster Compounds Bearing both High- and Low-Valent Transition Metal Fragments: The Reactions of Imido Carbonyl Cluster Ru3(CO)10(μ3-NPh) with Dioxo Acetylide Complexes (C5Me5)W(O)2(CCR), R = Ph and CMeCH2

“…The ligated acetylide then brought the (C 5 Me 5 )W(O) 2 fragment into the close vicinity of one Ru(CO) 3 unit and provided the driving force to induce the elimination of a CO and coordination of a WO fragment to the Ru atom. This proposed pathway is supported by the isolation of a butterfly WRu 3 cluster ( 9 ) from the condensation of acetylide complex CpW(CO) 3 (CCPh) and Ru 3 (μ 3 -NPh)(CO) 10 and by the formation of alkyne cluster 10 , which contains an open triangular metal skeleton, from the reaction of phosphinidene cluster Fe 3 (μ 3 -PPh)(CO) 10 with alkyne under UV photolysis . In the formation of 9 , the facile dissociation of CO ligands on tungsten has induced the migration of the imido ligand from the triruthenium face to the W−Ru edge, as the tungsten atom tends to interact more strongly with the electronegative nitrogen atom.…”

Synthesis of the Tetranuclear Clusters RuM3H(C⋮CFc)(CO)12 (M = Ru, Os; Fc = Ferrocenyl), Containing a Fluxional μ4-Acetylide Ligand. Structure of a Mixed Crystal Containing Tetranuclear (Ru4H(C⋮CFc)(CO)12) and Trinuclear (Ru3H(C⋮CFc)(CO)9) Ruthenium Complexes

“…(The alternative description of the C(13)−C(14) bond as a triple bond π-coordinated to both Ru(2) and Ru(3) atoms is inconsistent with the very long Ru(2)···C(14) distance of 3.10(1) Å.) Such coordination of the acetylide ligand in tetranuclear clusters has been found just in a few cases, viz., in the heteronuclear butterfly clusters (C 5 Me 5 )WOs 3 (C⋮CCH 2 OMe)(CO) 11 ( 3 ) (with the W atom at the wingtip position), (C 5 H 5 )WOs 3 (C⋮CPh)(CO) 11 ( 4 ) (with the W atom at the hinge position), and (C 5 H 5 )WRu 3 (C⋮CPh)(μ-NPh)(CO) 9 ( 5 ) (with the W atom at the hinge position) . In contrast to compounds 3 − 5 , cluster 2a represents the first homonuclear complex of this type and contains only carbonyl and hydride ligands along with the μ 4 -acetylide group.…”