Sequential conversion of ethyne into μ-vinylidene, μ-methylcarbyne and μ-methylcarbene at a di-ruthenium centre: X-ray structures of [Ru2(CO)2(μ-CO) (μ-CCH2) (η-C5H5)2] and [Ru2(CO)2(μ-CO) (μ-CCH3) (η-C5H5)2] [BF4]

The ethyne-derived demetallocycle [Ru₂(CO) (μ-CO){μ-C(O)C₂H₂}(η-C₅H₅)₂ isomerises in boiling toluene to yield the μ-vinylidene complex [Ru₂(CO)₂(μ-CO)(μ-CCH₂) (η-C₅H₅)₂], which on protonation with dry HBF₄ provides the μ-carbyne complex [Ru₂(CO)₂(μ-CO)(μ-CCH₃)(η-C₅H₅)₂][BF₄]; the structure of each product has been determined by X-ray diffraction. The μ-carbyne cation is attacked by hydride to produce the μ-methylcarbene complex [Ru₂(CO)₂(μ-CO)(μ-CHCH₃)(η-C₅H₅)₂].     

Conversion of allene into μ-dimethylcarbene at a diruthenium centre

Treatment of [Ru₂(CO)(μ-CO) {μ-C(O)C₂Ph₂} (η-C ₅H₅)₂] with allene in toluene at 100°C displaces diphenylacetylene and produces [Ru(CO)(η-C₅H₅)-{η³-C₃H₄Ru(CO)₂(η-C₅H₅)}]; upon protonation a 1-methylvinyl cation [Ru₂(CO)₂(μ-CO){μ-C(Me)CH₂}(η-C₅H₅)₂]⁺ is formed which undergoes nucleophillic attack by hydride to yield the μ-dimethylcarbene complex [Ru₂(CO)₂-(μ-CO)(μ-CMe₂)(η-C₅H₅)₂].     

Transformation of C2 units on a bimetallic tetranuclear cluster.: Reactivity of [Ru3Mo(μ3-η-CC)(μ-CO)3(CO)2(η-C5H4R)3(η-C5H5)] (R = H, Me)

The reactivity of [Ru₃Mo(μ₄-η²-CC)(μ-CO)₃(CO)₂(η-C₅H₄R)₃(η-C₅H₅)] (R = H; Me) have been investigated, initially to elucidate the nature of the starting material, and, latterly, to define the reactivity of an interesting ethane-1,2-bis(ylidyne) species. While the mixed RuMo clusters were unreactive towards simple electrophiles and carbonyl substitution by phosphine ligands they did react with atmospheric oxygen or carbon monoxide to give substantially different products. In all instances oxygen was incorporated either at the metal centre or at the C₂ fragment. High-pressure carbonylations yielded [Ru₃(μ-CO)₃(η-C₅H₅)₃(μ₃-C-C(O)O{Ru(CO)₂(η-C₅H₅)})] and [{Ru₂(μ-CO)(CO)₂(η-C₅H₄Me)₂}(μ₄-η²-CC){Ru(CO)(η-C₅H₄Me)Mo(η-C₅H₅)(=O)(μ-O)}], an ethane-1,2-bis(ylidene) complex, this exemplifying a relatively rare raft geometry which further reacted with Cl₂CCCl₂ to give [Mo₃(μ₄-C₂(Ru(CO)₂(η-C₅H₄Me))(CO)(μ-CO)(η-C₅H₅)₃(Cl)₂] having a similar geometry and undergone halogenation. In order to extend the extant examples of these raft clusters we explored the reaction of [{Ru(CO)₂(η-C₅H₄R)₂}₂(μ-C₂)] with [{Ru(CO)₂(η-C₅H₅)₂}₂] to provide a rational synthetic pathway leading to very reactive [Ru(μ₄-η²-CC)(μ₂-CO)₂(CO)₄(η-C₅H₄Me)₂(η-C₅H₄R)₂] rafts.     

A convenient entry into diruthenium chemistry

In boiling toluene, diphenylacetylene is readily displaced from the dimetallocycle [Ru₂(CO)(μ-CO) {μ-C(O)C₂Ph₂} (η-C₅H₅)₂] by a variety of reagents (P(OMe)₃, SO₂, R₂CN₂, Ph₂PCH₂) to produce [Ru₂(CO){P(OMe)₃}(μ-CO)₂ - (η-C₅H₅)₂] or [Ru₂(CO)₂(μ-CO)(μ-L)(η-C₅H₅)₂] (L  SO₂, CR₂, CH₂) in high yield.     

Molybdenum alkyl- and aryl-thiolates

The reaction between [(η⁵-C₅H₅)MoH(CO)₃] and disulphides gives dimeric or trimeric complexes depending upon the conditions. The syntheses of the novel trinuclear molybdenum carbonyl complex [{Mo(η⁵-C₅H₅)(SR)(μ-CO)(CO)}₃] (R = Me), and dinuclear compounds [Mo₂(η⁵-C₅H₅)(μ-SR)₃(CO)₄] (R = Me) and [Mo₂(η⁵-C₅H₅)₂(SR)₂(CO)₂(μ-SR)(μ-Br)] (R = Me or Ph) are reported.     

Electrophilic additions to unsaturated systems : By P.B.D. De la Mare and R. Bolton,Elsevier Scientific Publ. Co., Amsterdam and New York, 2nd Edition, 1982, xiii + 377 pages,U.S. $91.50, Dutch Fl. 215.00

The metalmetal double-bonded μ-alkyne complex [Ru₂(μ-CO)(μ-C₂Ph₂) (η-C₅H₅)₂] (1) reacts with diazomethane at 0°C to yield Ru₂(CO)(η-CH₂) {μ-C(Ph)C(Ph)CH₂} (η-C₅H₅)₂] (2) incorporating two methylene units, one bridging the metal atoms and one linked with the alkyne. Upon heating, a second carboncarbon bond formation occurs to link the methylene groups and give [Ru₂(CO)(μ-CO) {μ-C(Ph)C(Ph)C(H)Me} (η-C₅H₅)₂ (3); the structures of 1 and 2 were established by X-Ray diffraction.     

The cleavage of a coordinated SCNR group in [Fe(CO)2L2(η2-SCNR)] by [Co(η-C5H5)(PPh3)2] to give complexes containing μ3-CNR ligand. The preparation and structure of [{Co(η-C5H5)}2{Fe(CO)2(PPh3)}(μ3-S){μ3-CNC(O)C6H5}]

The reaction of [Fe(CO)₂(PPh₃)₂{η²-SCNC(O)Ph}] with [Co(η-C₅H₅)(PPh₃)₂] in benzene solution at room temperature results in the facile cleavage of the CS bond of the SCNC(O)Ph ligand to give [{Co(η-C₅H₅)}₂{Fe(CO)₂(PPh₃)}(μ₃-S{μ₃-CNC(O)Ph}], whereas [Fe(CO)₂(PPh₃)₂(η²-SCNMe)] gives [{Co(η-C₅H₅)} ₂₂{Fe(CO)(CNMe)(PPh₃)(μ₃-S)(μ₃-CO)]. The structure of [{Co(η-C₅H₅)}₂{Fe(CO)₂(PPh₃)} (μ₃-CNC(O)Ph}] has been confirmed by X-ray diffraction.     

The reaction of [H4Ru4(CO)12] with 1-penten-3-yne: dimerization and trimerization through the triple bonds

The clusters [Ru₄(μ-CO)(CO)₁₀(μ₄-η¹:η²:η¹:η²-C₅H₆)₂] (1), [Ru₄(CO)₈(μ₄-η⁴:η¹:η¹:η¹:η³-C₁₀H₁₂)(μ₃-η³:η²:η¹-C₅H₆)] (2) and [Ru₄(CO)₁₀(μ₄-η⁴:η¹:η¹:η³:η¹-C₁₅H₁₆)] (3) have been prepared from the reaction of [H₄Ru₄(CO)₁₂] with 1-penten-3-yne. This reaction is observed to proceed with dimerization and trimerization through the triple bonds. The products were characterized spectroscopically by ¹H- and ¹³C-NMR. X-ray crystal structures of compounds 1 and 2 are also described.     

The synthesis and reactivity of some indenyl and bis-indenyl ruthenium carbonyl complexes

The reaction of [Ru₃(CO)₁₂] (1), with indene in refluxing xylene affords [{(η⁵-C₉H₇)Ru(CO)₂}₂] (2), in high yield. An analogous reaction of 1 with 2-phenylindene affords the expected dinuclear complex [{(η⁵-C₉H₆Ph)Ru(CO)₂}₂] (5), and a heptaruthenium cluster [(C₉H₄Ph)Ru₇(μ-H)(μ-CO)₂(CO)₁₆] (6). The indenyl ligand in compound 6 exhibits a novel bonding mode in which the benzenoid ring is μ₄,η¹:η¹:η²:η² bound to the cluster. Refluxing 1 with bis-indenyl methane affords the dinuclear complex [Ru₂(CO)₄{μ-(η⁵-C₉H₆)₂CH₂}] (7), which reacts with iodine via Ru-Ru bond cleavage to give [Ru₂I₂(CO)₄{(η⁵-C₉H₆)₂CH₂}] (8).     

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

Reaction of the heteronuclear cluster RuOs₃(μ-H)₂(CO)₁₃ (1) with azulene under thermal activation afforded the novel clusters RuOs₃(μ-H)(CO)₉(μ₃,η⁵:η²:η²-C₁₀H₉) (3) and Ru₂Os₃(μ-H)₂(CO)₁₃(μ-CO)(μ₃,η⁵:σ²-C₁₀H₈) (5a), with 4,6,8-trimethylazulene to give RuOs₃(μ-H)(CO)₈(μ-CO)(μ,η⁵:η⁴-C₁₀H₆Me₃) (4) and Ru₂Os₃(μ-H)₂(CO)₁₃(μ-CO)(μ₃,η⁵:σ²-C₁₀H₅Me₃) (5b), and with guaiazulene to give Ru₂Os₃(CO)₁₁(μ₃,η⁵:η³:η³-C₁₀H₅Me₂ⁱPr) (6), respectively. In 3–5, cluster-to-ligand hydrogen transfer appears to have taken place, with the organic moiety capping a trimetallic face in 3, bridging a metal–metal bond in 4 and via a μ₃,η⁵:σ² bonding mode in 5a and 5b. Cluster 6 contains a trigonal bipyramidal metal framework with the guaiazulene ligand over a triangular metal face. All five clusters have been completely characterised, including by single-crystal X-ray diffraction analysis.     

A synthetic route to heteronuclear clusters containing iridium and rhodium: X-ray crystal structures of [IrOs3(μ-H)2(μ-Cl)(CO)12] and [Ir2Rh2(μ-CO)(μ3-CO)2(CO)4(η-C5Me5)2]

The iridium and rhodium complexes [MCl(CO)₂(NH₂C₆H₄Me-4)] (M = Ir or Rh) react with [Os₃(μ-H)₂(CO)₁₀] to give the tetranuclear clusters [MOs₃(μ-H)₂(μ-Cl)(CO)₁₂]; the iridium compound being structurally identified by X-ray diffraction. Similarly, [IrCl(CO)₂(NH₂C₆H₄Me-4)] and [Rh₂(μ-CO)₂(η-C₅Me₅)₂] afford the tetranuclear cluster [Ir₂Rh₂(μ-CO)(μ₃-CO)₂(CO)₄(η-C₅Me₅)₂], also characterised by single-crystal X-ray crystallog     

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

The heteronuclear cluster RuOs₃(μ-H)₂(CO)₁₃ (4) reacts with refluxing toluene to form the clusters Ru₂Os₃(μ-H)₂(CO)₁₆ (5) RuOs₃(CO)₉(μ-CO)₂(η⁶-C₆H₅Me) (6) and Ru₂Os₃(CO)₁₂(μ-CO)(η⁶-C₆H₅Me) (7). Cluster 5 exists as a mixture of five isomers. The inter-relationship among the clusters has also been investigated.     

The reactions of AgY salts with [Fe2(η-C5H5)2(CO)4-n(CNMe)n] complexes (Y−  NO3−, BF4− or PF6−; n  0, 1 or 2). The crystal structure of [Fe(η-C5H5)2(CNMe)]BF4

The oxidative cleavage of [Fe₂(η-C₅H₅)₂(CO)_4-n(CNMe)_n] (n=0−2) by 2AgX gives mononuclear products. It is shown to be a two-electron process in most solvents but a one-electron process in acetonitrile. The two-electron oxidations proceed by way of adducts such as [Fe₂(η-C₅H₅)₂(CO)(CNMe)(μ-CO){;μ-CN(Me)AgPPh₃};]BF₄ which are isolable when n = 2, detectable when n = 1 and postulatetd when n = 0. The one-electron process gives no adducts, and 1AgX cleaves all of the substrate to [Fe(η-C₅H₅)(CO)(L)(NCMe)]⁺ and [Fe(η-C₅H₅)(CO)(L)]^. (L  CO or CNME). The latter may combine or react with added CHBr₃ to give [Fe(η-C₅H₅)(CO)(L)Br]. The structure of [Fe(η-C₅H₅)(CO)₂-(CNMe)]BF₄ has been determined by X-ray diffraction.     

Reactivity of the heteronuclear cluster RuOs3(μ-H)2(CO)13 with indene

The heteronuclear cluster RuOs₃(μ-H)₂(CO)₁₃ (1) reacts with indene under thermal activation to afford the novel clusters RuOs₃(μ-H)(CO)₉(μ-CO)₂(η⁵-C₉H₇) (3), RuOs₃(μ-H)(CO)₉(μ₃,η⁵:η²:η²-C₉H₇) (4) and Ru₂Os₃(μ-H)(CO)₁₁(μ₃,η⁵:η²:η²-C₉H₇) (5), the latter two possessing indenyl ligands in the μ₃,η⁵:η²:η² bonding mode. Cluster 5 exists as a mixture of two isomers. The inter-relationship among the clusters has also been investigated.     

Synthesis of the compounds [Re(CR)(CO)2(η5-C9H7)][BF4] (R = C6H4Me-4 or C6H3Me2-2,6) and the preparation of complexes with FeRe bonds

The salts [Re(CR)CO)₂(η⁵-C₉H₇)][BF₄] [R = C₆H₄Me-4 or C₆H₃Me-2,6; η⁵- C₉H₇ = indenyl] have been prepared and used to synthesize the dimetal compounds [FeRe(μ-CR)(μ-NO)(CO)₄(η⁵-C₉H₇)]. The iron-rhenium species containing a bridging p- tolylmethylidyne ligands react with [Fe₂(CO)₉] or with [Ru(CO)₄(η-C₂H₄)], respectively, to yield the trimetal compounds ([FeMRe(μ₃-CC₆H₄Me-4)(μ-CO)(μ-NO)(CO)₆(η ₅-C₉H₇)] (M = Fe or Ru).     

The μ3-cyclopentadienylidene ligand: X-ray structure of [Ru4(CO)5 {P(OMe)3}(μ3-C5H4)2(η-C5H5)2]

UV irradiation of [Ru₂(CO)₄(η-C₅H₅)₂] yields the tri- and tetra-ruthenium complexes [Ru₂(CO)₄(η-C₅H₅){η-C₅H₄Ru(CO)₂(η-C₅H₅)}] and [Ru₄(CO)₆(μ₃-C₅H₄)₂(η-C₅H₅)₂]. The μ₃-C₅H₄ ligand in the latter has been characterised through an X-ray diffraction study on [Ru₄(CO)₅{P(OMe)₃}(μ₃-C₅H₄)₂(η-C₅H₅)₂].     

Ligand exchange between metals: synthesis and characterisation of binuclear and trinuclear iron-alkyne complexes. Crystal structures of [(η5-C5H5)2Fe3(CO)3(μ3-CO)(μ-CO)(CF3C2CF3] and [{μ-CF3CC(CF3)S} {Fe(CO)3}2]

Reaction of[(η⁵-C₅H₅)(CO)Fe{μ-C(CF₃)C(CF₃)SMe}₂Fe(CO)(η⁵-C₅H₅)] with Fe₃(CO)₁₂ leads to an exchange of ligands (hexafluorobut-2-yne, cyclopentadienyl or sulphur) between the metal centres and the formation of several new complexes.Two of These, [(η⁵-C₅H₅)₂Fe₃(CO)₃(μ₃-CO)(μ-CO)(CF₃C₂CF₃)] and [{μ-CF₃CC (CF₃)S Fe(CO)₃}₂], have been shown by X-ray diffraction to contain μ₃-η²-| CF₃C₂CF₃ units bridging Fe₃ and Fe₂S triangles, respectively.     

The reactions of AgI electrophile with [Fe2(η-C5H5)2(CO)2(L){CN(Me)H}]+ and [Fe2(η-C5H5)2(CO)2{CN(Me)H}2]2+ salts (L = CO or CNMe)

The protonated species [Fe₂(η-C₅H₅)₂(CO)₂(η-CO){μ-CN(Me)H}]X, [Fe₂(η-C₅H₅)₂(CO)(CNMe)(μ-CO){μ-CN(Me)H}][X], and [Fe₂(η-C₅H₅)₂(CO)₂{η-CN(Me)H}₂][X]₂ react with one equivalent of AgY. The Ag⁺ and one H⁺ act together as a two-electron oxidant. Silver metal is precipitated quantitatively and the substrates cleaved to give mono-nuclear products of the type (a) [Fe(η-C₅H₅)(CO)(L)X] and [Fe(η-C₅H₅(CO)(L)Y] or (b) Fe(η-C₅H₅(CO)(L)(CNMe)][X] (L = CO, CNMe). If X⁻ and Y⁻ are both coordinating anions such as NO₃⁻, I⁻, or Br⁻ or the solvent is MeCN products of type (a) are usually obtained with X = Y = MeCN⁺ if acetonitrile is used as the solvent. However, if either X⁻ or Y⁻ is a non-coordinating anion such as BF₄⁻ or PF₆⁻ and methanol is the solvent, the products are usually those of type (b). When X⁻ = [p-MeC₆H₄SO₃]⁻, both types of products are obtained in significant amounts. If two equivalents of Ph₃P are added to the methanol solution of [Fe₂(η-C₅H₅)₂(CO)₂{-CN(Me)H}₂[BF₆]₂, no reaction takes place until the third equivalent of AgNO₃ has been added. The products have been isolated and characterized by analysis and infrared spectroscopy. The previously unreported [Fe₂(η-C₅H₅)₂(CO)(CNMe)(η-CO){η-CN(Me)H}] X salts are described for X⁻ = BF₄⁻, PF₆⁻, Br⁻ · 2H₂O, I⁻ · H₂O, NO₃⁻ · 0.5H₂O, and p-MeC₆H⁴SO₃⁻.     

Ruthenium cluster chemistry: Monodentate bis(diphenylphosphino)acetylene-ligated cluster modules in chain and dendrimer formation

Reaction of Ru₃(μ-dppm)(CO)₁₀ [dppm = bis(diphenylphosphino)methane] with one equivalent of dppa [dppa = bis(diphenylphosphino)acetylene] afforded Ru₃(μ-dppm)(CO)₉(η¹-dppa) which possesses a monodentate dppa ligand,an X-ray structural study revealing that all phosphorus donor atoms are arranged in equatorial coordination sites with respect to the triruthenium cluster plane.Reaction of Ru₃(CO)₉(NCMe)₃ with excess dppa afforded fair yields of Ru₃(CO)₉(η¹-dppa)₃,which possesses three monodentate dppa ligands.Reaction of three equivalents of Ru₃(μ-dppm)(CO)₉(η¹-dppa) with Ru₃(CO)₉(NCMe)₃ or reaction of Ru₃(CO)₉(η¹-dppa)₃ with excess Ru₃(μ-dppm)(CO)₁₀ afforded low yields of the dodecanuclear first-generation dendrimer Ru₃(CO)₉{PPh₂C₂PPh₂Ru₃(μ-dppm)(CO)₉}₃.Reaction of WIr₃(μ-CO)₃(CO)₈(η-C₅Me₅) with excess Ru₃(μ-dppm)(CO)₉(η¹-dppa) afforded fair yields of the decanuclear dppa-bridged tri-cluster WIr₃(CO)₉{PPh₂C₂PPh₂Ru₃(μ-dppm)(CO)₉}₂(η-C₅Me₅).     

Isonitrilsynthesen am komplex: V. Desulfurierung von isothiocyanaten in carbonylmetallat-additions-verbindungen

The isocyanide complexes [Fe(η-C₅H₅)(CO)₂CNR][PF₆] and Cr(CO)₅CNR (R = CH₃, C₆H₁₁, C₆H₅) are conveniently prepared at ?50°C from carbonyl metallates, isothiocyanates, and phosgene. At room temperature Na[Fe(η-C₅H₅)(CO)₂] reacts with isothiocyanates ($\text{1}\text{1}$) to give the isocyanide bridged complexes [Fe₂(η-C₅H₅)₂(μ-CO)(μ-CNR)(CO)₂].