Synthesis, Characterization and Crystal Structures of Some Linked Metal Carbonyl Clusters Derived from Diethynyl-Substituted Silane and Disilane Ligands

The use of diethynylsilane, diethynyldisilane and diethynyldisiloxane in the synthesis of some linked metal carbonyl clusters is demonstrated. New dimeric η²-diyne complexes of cobalt [{Co₂(CO)₆}₂(η²-diyne)], ruthenium [{(μ-H)Ru₃(CO)₉}₂(μ₃-η²,η²-diyne)] and osmium [{(μ-CO)Os₃(CO)₉}₂(μ₃-η²-diyne)] {diyne=HC≡CSi(CH₃)₂C≡CH, HC≡CSi(CH₃)₂–Si(CH₃)₂C≡CH, HC≡CSi(CH₃)₂–O–Si(CH₃)₂C≡CH or HC≡CSi(Ph)₂C≡CH} have been prepared in good yields from the reaction of [Co₂(CO)₈], [Ru₃(CO)₁₂] and [Os₃(CO)₁₀(NCMe)₂] with half an equivalent of the appropriate diyne ligand, respectively. All the twelve compounds have been characterized by IR and ¹H NMR spectroscopies and mass spectrometry. The molecular structures of eight of them have been determined by X-ray crystallography. Structurally, each of the tetracobalt species displays two Co₂C₂ cores adopting the pseudo-tetrahedral geometry with the alkyne bond lying essentially perpendicular to the Co–Co vector. For the group 8 ruthenium and osmium analogues, the hexanuclear carbonyl clusters consist of two trinuclear metal cores with the μ₃-η²,η² bonding mode for the acetylene groups in the former case and μ₃-(η²-||) bonding mode in the latter one. Density functional theory was employed to study the electronic structures of these molecules in terms of the nature of the silyl or disilyl unit and its substituents.     

Intramolecular Cyclization of Butadiyne Functionalized Ligands coordinated to Triosmium‐Carbonyl Cluster

Reactions between diynes and [Os₃(CO)₁₁(CH₃CN)] in the presence of water give rise to the formation of intriguing hydride triosmium clusters [Os₃(μ‐H)(CO)₉{μ₃,η¹:η³:η¹‐RC₂COHC≡CR}] ( 1a – 1c ) under mild conditions in high yields. When these allylic alcohol compounds 1a – 1c are dissolved in dry polar and donor solvents, an intramolecular cyclization process takes place to give [Os₃(μ‐H)(CO)₉{μ₃,η¹:η³:η¹‐RC₂CH=COCR}] ( 2a – 2c ) in quantitative yield. The utilization of [Os₃(CO)₁₁(CH₃CN)] as starting material together with the addition of water can replace the inconvenient use of [Os₃(μ‐H)₂(CO)₁₀]. This method of synthesis provides a facile pathway for diyne cyclizations and has a clear advantage over those described to date in the literature. Additionally, the analogous cyclized mixed‐metal complex [Os₃(μ‐H)(CO)₉{μ₃,η¹:η³:η¹‐FcC₂CH=COCFc}] ( 2d ) (Fc = ferrocenyl), was synthesized in order to carry out a comparative electrochemical study with the related compounds [Os₃(CO)₁₁(μ₃‐FcC₄Fc)] ( I ) and [Os₃(CO)₁₀(μ₃‐FcC₄Fc)] ( II ), which were previously reported by R. D. Adams.     

IR frequencies and intensities of the vibrational modes of Cx Hy fragments bonded to metal complexes. Relationship with structure,bonding and reactivity

The following organometallic complexes were studied as models of the coordination between metal atoms and different C_x H_y ligands: Co₂Fe(CO)₉(CCH₂), Co₂Ru(CO)₉(CCH₂), Os₃(H)₂(CO)₉(CCH₂) and Co₂Fe(CO)₉(CC(H)CH₃) (η₃-η₂-vinylidene or μ₃-η₂-methylvinylidene group); Fe₂(C₅H₅)₂(CO)₃(CCH₂) (μ₂-η¹-vinylidene group); Os₃(μ-H)(CO)₉(CHCH₂) (μ₂-η²-vinyl group); CH₃Mn(CO)₅ (η¹-methyl group); Os₃(μ-H)₂(Co)₁₀(CH₂) and Fe₂(CO)₈(CH₂) (μ₂-η¹-methylene group); Co₃(CO)₉(CH) (μ₃-methyne group); CO₃(CO)₉(CCH₃) (μ₃-η¹-ethylidyne group); Os₃(H)(CO)₉(C₂H) (μ₃-η²-acetylide group). The infrared frequencies and intensities associated with the main vibrational modes of the ligands (CC and CH stretchings, CH deformations) were evaluated and compared with those of appropriate model molecules. Both the frequency and intensity data can be usefully correlated with structural parameters (e.g. CC and CH bond distances and HCH bond angles) and provide information on the charge distribution on the ligands. It is therefore possible to discuss the type of metal—ligand interaction and the balance between the σ and π contributions to the bond.     

Bridging allyl ligands upon allene insertion into electron-deficient triosmium-hydride clusters [Os3(CO)9(μ3-NSC7H3R)(μ-H)] (R = H, Me)

Allene reacts with the benzothiazolide clusters [Os₃(CO)₉(μ₃-NSC₇H₃R)(μ-H)] (R = H, Me) to afford the bridging allyl complexes [Os₃(CO)₇(μ-CO)₂(μ-NSC₇H₃R)(μ-η¹:η²:η¹-CH₂CHCH₂)] resulting from insertion of allene into the metal-hydride. Both have been crystallographically characterized and differ with respect to the relative arrangement of allyl and benzothiazolide at the triosmium centre.     

Synthesis and characterization of triosmium and triruthenium pyrene clusters

The reaction between 1-pyrenecarboxaldehyde (C₁₆H₉CHO) and the labile triosmium cluster [Os₃(CO)₁₀(CH₃CN)₂] gives rise to the formation of two new compounds by competitive oxidative addition between the aldehydic group and an arene C-H bond, to afford the acyl complex [Os₃(CO)₁₀(μ-H)(μ-COC₁₆H₉)] (1) and the compound [Os₃(CO)₁₀(μ-H) (C₁₆H₈CHO)] (2), respectively. Thermolysis of [Os₃(CO)₁₀(μ-H)(μ-C₁₆H₉CO)] (1) in n-octane affords two new complexes in good yields, [Os₃(CO)₉(μ-H)₂(μ-COC₁₆H₈)] (3) and the pyryne complex [Os₃(CO)₉(μ-H)₂(μ₃-η¹:η¹:η²-C₁₆H₈)] (4).In contrast, when 1-pyrenecarboxaldehyde reacts with [Ru₃(CO)₁₂] only one product is obtained, [Ru₃(CO)₉(μ-H)₂(μ₃-η¹:η¹:η²-C₁₆H₈)] (5), a nonacarbonyl cluster bearing a pyrene ligand. All compounds were characterized by analytical and spectroscopic data, and crystal structures for 1, 2, 4 and 5 were obtained.     

Synthesis and properties of Rh6- and Os3-cluster-containing monomers and their copolymers with styrene

Cluster metal-containing monomers were obtained and characterized. Mono- and disubstituted products were obtained under mild conditions via the interaction of Rh₆(CO)₁₆ with 4-vinylpyridine (4-VPy) in the presence of trimethylamin-N-oxide. Substitution of labile acetonitrile ligand in Rh₆(CO)₁₅NCMe by allyldiphenylphosphine (AlPPh₂) yields Rh₆(CO)₁₄(μ,η²-PPh₂CH₂CH=CH₂) with formation of π-complex. The structures of Rh₆(CO)₁₅(4-VPy), Rh₆(CO)₁₄(μ,η²-PPh₂CH₂CH=CH₂) and (μ-H)Os₃(μ-OCNM₂)(CO)₉PPH₂CH₂CH=CH₂ have been determined by single-crystal X-ray diffraction studies, as well as by IR-, ¹H NMR spectroscopies. The Rh - Rh bond lengths are within 2.72÷2.80 Å. The copolymerization of cluster-containing monomers synthesized with traditional monomers has been studied. It was found that Rh₆- and Os₃-containing monomers did not change either the ligand surroundings or the structure of cluster monomer framework during polymerization reaction.     

Reaction of alkyne cluster Os3(μ-CO)(CO)9(μ3-η1:η1:η2-Me3SiC2Me) with HC≡CCOOMe. Molecular and crystal structures of Os3(CO)9{μ3-η1:η1:η2:η2-C(SiMe3)C(Me)C(COOMe)CH× and Os3(CO)8{μ3-η1:η1:η4:η1-C(SiMe3)C(Me)C(H)C(COOMe)CH× complexes

Reaction of the cluster Os₃(μ-CO)(CO)₉(μ₃-η¹:η¹:η²-Me₃SiC₂Me) with HC≡CCOOMe in benzene at 70 °C results in Os₃(CO)₉{μ₃-η¹:η¹:η²:η²-C(SiMe₃)C(Me)C(COOMe)CH× (5), Os₃(CO)₉{μ₃-η¹:η¹:η²:η²-C(SiMe₃)C(Me)C(H)C(COOMe)CH× (6), Os₃(CO)₉{μ-η¹:η¹:η⁴-C(SiMe₃)C(Me)C(H)C(COOMe)CH× (7), and Os₃(CO)_δ{μ₃-η¹:η¹:η⁴:η¹-C(SiMe₃)C(Me)C(H)C(COOMe)× complexes (8), containing an osmacyclopentadiene moiety. Complexes5–8 were characterized by¹H NMR and IR spectroscopy. The structure of clusters5 and8 was confirmed by X-ray analysis. Complex7 is formed from cluster5 as a result of a new intramolecular rearrangement and complex8 is obtained by decarbonylation of compound6. Complex8 adds PPh₃ to give Os₃(CO)_δ(PPh₃){μ-η¹:η¹:η⁴-C(SiMe₃)C(Me)C(H)C(COOMe)×.     

Os3(CO)9{μ3-η1-η1-η2-η2-C(SiMe3)C(Me)C(H)C(Fc)}, the second example of a cluster with the “face” coordination of the metallacyclopentadiene fragment and its conversion to the Os3(μ-H)(CO)8{μ3-η1-η1-η4-η1-C(SiMe3)C(Me)C(H)C(C5H3FeC5H5)} complex with theortho-metallated ferrocene moiety

Os₃(μ-CO)(CO)₉(μ₃-Me₃SiC₂Me) alkyne complexes react with ferrocenylacetylene in hot benzene to form Os₃(CO)₉{μ₃-η¹-η¹-η²-η²-C(SiMe₃)C(Me)C(H)C(Fe)} and a small amount of the isomeric Os₃(CO)₉(μ-η¹-η¹-η⁴-C(SiMe₃)C(Me)C(Fc)C(H)} complex. The structure of the major isomer was confirmed by X-ray structural analysis of the single crystal. Thermolysis of this complex in refluxing benzene affords the Os₃(μ-H)(CO)₈{μ₃-η¹-η¹-η⁴-η¹-C(SiMe₃)C(Me)C(H)(C₅H₃FeC₅H₅)} complex with theortho-metallated ferrocene moiety. The spectral characteristics of clusters with the μ₃-η¹-η¹-η²-η² and μ-η¹-η¹-η⁴ coordinations of the metallacyclopentadiene fragment have been established, which made it possible to choose between the alternative modes of bonding of diene with the trimetallic core.     

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.     

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.     

Reactions of benzothiazolide triosmium clusters with tetramethylthiourea

The valence saturated benzothiazolide triosmium cluster [Os₃(CO)₁₀(μ-η²-C₇H₄NS)(μ-H)] (1) reacts with tetramethylthiourea in refluxing toluene to give [Os₃(CO)₈(μ-η²-C₇H₄NS)(η²-SCNMe₂NMeCH₂)(μ-H)₂] (5), which exists as a mixture of two isomers in solution, whereas the electron-deficient cluster [Os₃(CO)₉(μ₃-η²-C₇H₄NS)(μ-H)] (2) reacts with tetramethylthiourea in refluxing cyclohexane to give two new compounds [Os₃(CO)₈(μ-η²-C₇H₄NS)(η²-SCNMe₂NMeCH₂)(μ-H)₂] (6) and [Os₃(CO)₉(μ-η²-C₇H₄NS)(η¹-SC(NMe₂)₂)(μ-H)] (7). In contrast, the reaction of [Os₃(CO)₉(μ₃-η²-C₇H₃(2-CH₃)NS)(μ-H)](3) with tetramethylthiourea in refluxing cyclohexane at 81 °C, gives only [Os₃(CO)₉(μ-η²-C₇H₃(2-CH₃)NS)(η¹-SC(NMe₂)₂)(μ-H)] (8) in 15% yield. Compound 7 converts into 6 in refluxing toluene whereas a similar thermolysis of 8 results non-specific decomposition. All the compounds have been characterized by elemental analysis, IR, ¹H NMR and mass spectroscopic data together with single crystal X-ray diffraction analysis for 5 and 7. Both compounds 5 and 6 contain a cyclometallated tetramethylthiourea ligand which is chelating at the rear osmium atom and are structurally very similar. In 5, the benzothiazolide ligand is coordinated to Os₃ triangle via the nitrogen lone pair and C(2) carbon atom of the heterocyclic ring whereas in 6 the ligand is coordinated to the Os₃ triangle via the nitrogen lone pair and the C(7) carbon atom of carbocyclic ring. In 7 and 8, the tetramethylthiourea ligand is coordinated at an equatorial site of the osmium atom which is also bound to the nitrogen atom of the benzothiazolide ligand.     

Reactivity of triosmium clusters with 3,4-dimethyl-1-phenylphosphole and cyanoethyldi-tert-butylphosphine ligands: X-ray crystal structures of [Os3(CO)9(μ-OH)(μ-H)(η1-PhPC4H2Me2)] and [Os3(CO)11(η1- t Bu2PC2H4CN)]

Reaction of [Os₃(μ-H)₂(CO)₁₀] with 3,4-dimethyl-1-phenylphosphole in refluxing cyclohexane affords two substituted triosmium clusters: [Os₃(CO)₉(μ-H)(μ³:η¹:η¹:η²-PhPC₄H₃Me₂)] (1) and [Os₃(CO)₉(H)(μ²-η¹:η²-PhPC₄H₄Me₂)] (2), of which cluster 2 exhibits two chromatographically non-separable isomeric forms attributed to terminal and bridging coordination of the hydride ligand, respectively. When this reaction is performed in refluxing THF, the only product is the cluster [Os₃(CO)₉(μ-OH)(μ-H)(η¹-PhPC₄H₂Me₂)] (3). Crystallographic information obtained for cluster 3 shows the phosphole ligand occupying an equatorial position, as expected, while the OH group is asymmetrically bridging unlike previously reported similar compounds. Additionally, interaction of the labile cluster [Os₃(CO)₁₁(CH₃CN)] with cyanoethyldi-tert-butylphosphine in dichloromethane at room temperature was found to give [Os₃(CO)₁₁(η¹- ^t Bu₂PC₂H₄CN)] (4) as the only product; its crystallographic characterization shows that the phosphine ligand coordinates by means of the phosphorus atom in an equatorial fashion, analogous to compound 3.     

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].     

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.     

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     

Synthesis, characterization and reactivity studies of the new compound [Os3(CO)9(μ3-η,η,η-{C5H5FeC5H3CCC(S)C(Fc)CHO}]

Processes such as S-C and C-H bond activations as well as C-C coupling reactions have taken place in the synthesis of the new compound [Os₃(CO)₉(μ₃-η²,η³,η³-{C₅H₅FeC₅H₃CCC(S)C(Fc)CHO}] (Fc = C₅H₄FeC₅H₅), which contains an aldehyde oxametallacycle. A reactivity study of it has been carried out. In addition, other new triosmium clusters such as [Os₃(CO)₉(μ₃,η²-CCFc)(μ,η¹-SCCFc)], [Os₃(CO)₁₀(μ,η²-CCFc)(μ,η¹-SCCFc)] and [Os₃(CO)₉(μ-CO)(μ₃,η²-FcCCSCCFc)] have been prepared from the reaction of [Os₃(CO)₁₀(NCMe)₂] and FcCCSCCFc. All the compounds have been characterized by analytical and spectroscopic techniques. The crystal structures of [Os₃(CO)₉(μ₃,η²-CCFc)(μ,η¹-SCCFc)] and [Os₃(CO)₉(μ₃-η²,η³,η³-{C₅H₅FeC₅H₃CCC(S)C(Fc)CHO}] have been determined by X-ray crystallography and some electrochemical studies have also carried out.     

A comparative study of the reactivity of unsaturated triosmium clusters [Os3(CO)8{μ3-Ph2PCH2P(Ph)C6H4}(μ-H)] and [Os3(CO)9{μ3-η-C7H3(2-Me)NS}(μ-H)] with BuNC

Treatment of unsaturated [Os₃(CO)₈{μ₃-Ph₂PCH₂P(Ph)C₆H₄}(μ-H)] (2) with ^tBuNC at room temperature gives [Os₃(CO)₈(CNBu^t)){μ₃-Ph₂PCH₂P(Ph)C₆H₄}(μ-H)] (3) which on thermolysis in refluxing toluene furnishes [Os₃(CO)₇(CNBu^t){μ₃-Ph₂PCHP(Ph)C₆H₄}(μ-H)₂] (4). Reaction of the labile complex [Os₃(CO)₉(μ-dppm)(NCMe)] (5) with ^tBuNC at room temperature affords the substitution product [Os₃(CO)₉(μ-dppm)(CNBu^t)] (6). Thermolysis of 6 in refluxing toluene gives 4. On the other hand, the reaction of unsaturated [Os₃(CO)₉{μ₃-η²-C₇H₃(2-Me)NS}(μ-H)] (7) with ^tBuNC yields the addition product [Os₃(CO)₉(CNBu^t){μ-η²-C₇H₃(2-Me)NS}(μ-H)] (8) which on decarbonylation in refluxing toluene gives unsaturated [Os₃(CO)₈(CNBu^t){μ₃-η²-C₇H₃(2-Me)NS}(μ-H)] (9). Compound 9 reacts with PPh₃ at room temperature to give the adduct [Os₃(CO)₈(PPh₃)(CNBu^t){μ-η²-C₇H₃(2-Me)NS(μ-H)] (10). Compound 8 exists as two isomers in solution whereas 10 occurs in four isomeric forms. The molecular structures of 3, 6, 8, and 10 have been determined by X-ray diffraction studies.     

The activation and transformations of acenaphthylene by osmium carbonyl cluster complexes

The reaction of Os₃(CO)₁₀(NCMe)₂ (1) with an excess of acenaphthylene at room temperature provided the complex Os₃(CO)₁₀(μ-H)(μ-η²-C₁₂H₇) (2). Compound 2 contains a σ-π coordinated acenaphthyl ligand bridging an edge of the cluster. Compound 2 was converted to the complex Os₃(CO)₉(μ-H)₂(μ₃-η²-C₁₂H₆) (3) when heated to reflux in a cyclohexane solution. Compound 3 contains a triply bridging acenaphthyne ligand. Compound 3 reacts with acenaphthylene again at 160 °C to yield four new cluster complexes: Os₄(CO)₁₂(μ₄-η²:η²-C₁₂H₆) (4); Os₂(CO)₆(μ-η⁴-C₂₄H₁₂) (5); Os₃(CO)₉(μ-H)(μ₃-η⁴-C₂₄H₁₃) (6); and Os₂(CO)₅(μ-η⁴-C₂₄H₁₂)(η²-C₁₂H₈) (7). All compounds were characterized crystallographically. Compound 4 is a butterfly cluster of four osmium atoms bridged by a single acenaphthyne ligand. Compounds 5 and 7 are dinuclear osmium clusters containing metallacycles formed by the coupling of two equivalents of acenaphthyne. Compound 6 is a triosmium cluster formed by the coupling of an acenaphthyne ligand to an acenapthyl group that is coordinated to the cluster through a combination of σ and π-bonding.     

Reaction of tri(2-furyl)phosphine with triosmium clusters: C-H and P-C activation to afford furyne and phosphinidene ligands

Addition of tri(2-furyl)phosphine, PFu₃, to [Os₃(CO)₁₀(μ-H)₂] at room temperature gives [HOs₃(CO)₁₀(PFu₃)(μ-H)] (1), while in refluxing toluene the same reactants afford [Os₃(CO)₉{μ₃-PFu₂(C₄H₂O)}(μ-H)] (2) resulting from orthometallatation of a furyl ring. Reaction of PFu₃ with [Os₃(CO)_10−n(NCMe)_n] (n = 0, 1, 2) affords the substituted clusters [Os₃(CO)_12−n(PFu₃)_n] (n = 1-3) (3-5), the phosphine ligands occupying equatorial position in all cases. Heating [Os₃(CO)₁₁(PFu₃)] (3) in refluxing octane gives [Os₃(CO)₉(μ₃-PFu)(μ₃-η²-C₄H₂O)] (6) which results from both carbon-hydrogen and carbon-phosphorus bond activation and contains both μ₃-η²-furyne and furylphosphinidene ligands. All new clusters have been characterized by spectroscopic methods together with single crystal X-ray diffraction for 2, 3 and 6.     

Synthesis and structures of the silyl bridged bis(indenyl) diruthenium complexes and a novel indenyl nonanuclear ruthenium cluster Ru9(μ6-C)(CO)14(μ3-η:η:η-C9H7)2

Thermal treatment of C₉H₇SiMe₂C₉H₇ and C₉H₇Me₂SiOSiMe₂C₉H₇ with Ru₃(CO)₁₂ in refluxing xylene gave the corresponding diruthenium complexes (E)[(η⁵-C₉H₆)Ru(CO)]₂(μ-CO)₂ [E = Me₂Si (1), Me₂SiOSiMe₂ (2)]. A desilylation product [(η⁵-C₉H₇)Ru(CO)]₂(μ-CO)₂ (3) was also obtained in the latter case. Similar treatment of C₉H₇Me₂SiSiMe₂C₉H₇ with Ru₃(CO)₁₂ gave a novel indenyl nonanuclear ruthenium cluster Ru₉(μ₆-C)(CO)₁₄(μ₃-η⁵:η²:η²-C₉H₇)₂ (5) with carbon-centered tricapped trigonal prism geometry, in addition to the diruthenium complex (Me₂SiSiMe₂)[(η⁵-C₉H₆)Ru(CO)]₂(μ-CO)₂ (4) and the desilylation product 3. Complex 4 can undergo a thermal rearrangement to form the product [(Me₂Si)(η⁵-C₉H₆)Ru(CO)₂]₂ (6). The molecular structures of 1, 2, 4, 5, and 6 were determined by X-ray diffraction.