Parent Cyclopentadienyl Ruthenium(II) Chloride Synthon: Derivatization to CpRu Amido, Imido, and Oxo Complexes

Abstract

The complex salt [CpRu­(η6-C10H8)]­[(CpRu)2(μ-Cl)3] ([1]­[2]) was synthesized and found to be a useful CpRuCl synthon. The ions [1]+ and [2]− cleanly comproportionate into monomeric CpRuCl­(L)2 complexes with liberation of naphthalene upon treatment with donor ligands L such as DMSO, tBuNH2, 1,5-cycloctadiene, and CO. The amine adduct [CpRuCl­(NH2 tBu)2] allows access to the coordinatively unsaturated dimeric amido complex [CpRu­(NHtBu)]2, which is subsequently transformed into the bridging imido complexes [(CpRu)2(μ-NtBu)­(μ-CH2)] and [(CpRu)2(μ-NtBu)­(μ-CH)]+. The imido methylidyne complex shows enhanced electrophilicity at the methylidyne carbon compared to its bulkier C5Me5 congener and also allows access to a less hindered parent Cp version of the diruthenocarbene ligand in the form of the Ru2Cu μ3-carbido complex [(CpRu)2(μ-NtBu)­(μ3-C)­Cu­{N­(SiMe3)2}]. The salt [1]­[2] also gives a novel tetranuclear μ4-oxo cluster [(CpRuCl)4(μ4-O)] upon oxidation in air or by N-methylmorpholine N-oxide.

Synthesis, Reactivity, and Coordination of Semihomologous dppf Congeners Bearing Primary Phosphine and Primary Phosphine Oxide Groups

“…All syntheses were performed in argon or nitrogen atmosphere using standard Schlenk techniques and oven-dried glassware. Compounds 3 , [(η 5 -C 5 H 5 )­RuCl­(PPh 3 ) 2 ], [(η 5 -C 5 H 5 )­Ru­(MeCN-κ N ) 3 ]­[PF 6 ], and [(η 5 -C 5 H 5 )­RuCl­(cod)] (cod = η 2 :η 2 -cycloocta-1,5-diene) were prepared according to literature procedures. Other chemicals were purchased from commercial suppliers (Sigma-Aldrich or Alfa-Aesar) and used as received.…”

Four-Electron Reduction of Dioxygen on a Metal Surface: Models of Dissociative and Associative Mechanisms in a Homogeneous System

“…The Cp analogue of 2a and 2b , i.e., [{CpRu­(μ-H)} 4 (μ 3 -H) 2 ] ( 2c ), also reacted with O 2 to yield the mono-oxygenated complex [(CpRu) 4 (μ 3 -O)­(μ-H) 4 ] ( 4b ; Scheme ). Unlike 4a , 4b underwent a further mono-oxygenation to yield the bis­(μ 3 -oxo) complex [(CpRu) 4 (μ 3 -O) 2 (μ 3 -H) 2 ] ( 5 ). , The different reactivity of the mono­(μ 3 -oxo) complexes is presumably due to the difference in their hydricity. Because 4b has fewer electron-donating Cp ligands, its hydrides should be more acidic than those in 4a .…”

“…Unlike 4a, 4b underwent a further mono-oxygenation to yield the bis(μ 3 -oxo) complex [(CpRu) 4 (μ 3 -O) 2 (μ 3 -H) 2 ] (5). 16,21 The different reactivity of the mono(μ 3 -oxo) complexes is presumably due to the difference in their hydricity. Because 4b has fewer electron-donating Cp ligands, its hydrides should be more acidic than those in 4a.…”

Transition Metal Carbide Complexes

“…Starting from the naphthalene-containing Ru II salt, [Ru­(C 10 H 8 )­Cp]­[CpRu­(μ-Cl) 3 RuCp], sequential treatment with t BuNH 2 and Li­(NH t Bu) provides the amide-bridged complex, [CpRu­(μ-NH t Bu)] 2 , which reacts with the sulfur ylide, Ph 2 SCH 2 , to provide the methylene-bridged complex, [(μ-N t Bu)­(CpRu) 2 (μ-CH 2 )]. Hydride abstraction using [Ph 3 C]­[BF 4 ] affords the methylidyne complex, [(μ-N t Bu)­(CpRu) 2 (μ-CH)]­BF 4 , which reacts sequentially with (Et 4 N)­[CuI 2 ] and K­{N­(SiMe 3 ) 2 } to afford [(μ-N t Bu)­(CpRu) 2 (μ 3 -C)­Cu­{N­(SiMe 3 ) 2 }] …”