Synthesis and structure of the cluster Fe2Mo2(μ3-Se)(μ3-AsMe)(μ3-Co)(μ-Co)(Co)5(η5-Cp)2

The reaction of (Et₄N)₂[Fe₃(μ₃-Se)(Co)₉] with MeAsI₂ afforded the [Fe₃(μ₃-Se)(μ₃-AsMe)(Co)₉] cluster, which was characterized by¹H NMR and IR spectroscopy and elemental analysis. The reaction of the resulting compound with the dimeric, complex [η⁵-CpMo(CO)₃#x005D;₂ inm-xylene upon refluxing gave the heterometallic cluster Fe₂Mo₂(μ₃-Se)(μ₃-AsMe)(μ₃-Co)(μ-Co)(Co)₅(η⁵-Cp)₂, whose structure was established by X-ray diffraction analysis. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 996–998, May, 1999.     

S2CPR3 adducts as bridging ligands in tricobalt clusters. X-Ray structure of [Co3(CO)7(μ3-CH)(μ-S2CPCy3)]

[Co₃(CO)₉(μ₃-CX)] (X  H, Cl) react with S₂CPR₃ (R  cyclohexyl, Cy or isopropyl, ⁱPr) in CH₂ Cl₂ to give heptacarbonyltricobalt clusters [CO₃(CO)₇(μ₃-CX)(μ₂-S₂CPR₃)] in which the S₂CPR₃ act as four-electron ligands, bridging a CoCo cluster edge in a σ(S), σ(S′) fashion, as shown by an X-ray determination on a crystal of the derivative with X  H, R  Cy. The five-membered CoSCSCo ring is nearly perpendicular to the CO₃ triangle (i.e. axial), in contrast to the equatorial disposition usually found in related complexes with phosphorus ligands.     

Molecular structure and fluxional behaviour of the iron-rhodium methoxymethylidyne cluster complex Fe2 Rh(μ-H)(μ3-COCH3)(CO)7(η-C5H5)

The complex Fe₂Rh(μ-H)(μ₃-COCH₃)(CO)₇(η-C₅H₅) prepared by treatment of Fe₃(μ-H)(μ-COCH₃)(CO)₁₀ with Rh(CO)₂ (η-C₅H₅), has been examined by single crystal X-ray diffraction. The compound crystallises in the monoclinic space group C2/c (No. 15) with a 25.409(2), b 8.129(1), c 17.044(1) Å, β 103.744(6)°, V 3419.6(6) ų and D_c 2.02 g cm⁻³ for Z = 8 and M = 519.8. Data were collected for 2° ⩽ θ ⩽ 30° with graphite monochromated X-radiation (Mo-K_α) using an Enraf-Nonius CAD4-F diffractometer. The structure was refined to R = 0.025 (R_itw = 0.037) for 3557 observed [I ⩾ 3(σI)], absorption corrected data. The complex contains an asymmetrically bonded methoxymethylidyne ligand capping an Fe₂Rh triangular face (Fe(1)-C(8) 1.863(3), Fe(2)-C(8) 1.881(3), Rh-C(8), 2.211(3) Å). The terminal carbonyl ligand on the rhodium atom shows slight semi-bridging interactions with the two iron atoms (Fe(1) … C(7) 2.888(4), Fe(2) … C(7), 2.769(4) Å, Rh-C(7)-O(7) 169.1(4)°. The iron—iron vector is spanned by a (directly located) μ-hydride ligand. Variable temperature ¹³C NMR studies reveal fluxional behaviour, including a temperature dependence both of the alkylidyne carbon chemical shift (δ 323.5 at +80°C, δ 319.2 at −90°C) and its ¹⁰³Rh coupling constant (¹J(Rh-C) 23 Hz at −90°C, 26 Hz at +80°C). These data suggest an increased interaction of the ‘semi-μ₃’ alkylidyne ligand with the rhodium centre at higher temperatures, primarily associated with the highest energy fluxional process. Extended Hückel MO calculations on this complex allow a rationalisation of the ‘semi-μ₃’ nature of the COCH₃ group.     

Lithium and lanthanum complexes with acenaphthylene dianion. Molecular structure of [Li(Et2O)2]2μ2:η3[Li(η3:η3-C12H8)]2 complex

The lithium complex with the acenaphthylene dianion [Li(Et₂O)₂]₂₂:³[Li(³:³-C₁₂H₈)]₂ (1) was synthesized by the reduction of acenaphthylene with lithium in diethyl ether. According to the X-ray diffraction data, compound 1 has a reverse-sandwich structure with the bridging dianion ₂:³[Li(³:³-C₁₂H₈)]₂. Two lithium atoms in complex 1 are located between two coplanar acenaphthylene ligands of the ₂:³[Li(³:³-C₁₂H₈)]₂ ^2– dianion and are ³-coordinated with the five- and six-membered rings. The lanthanum complex with the acenaphthylene dianion [LaI₂(THF)₃]₂(₂-C₁₂H₈) (2) was synthesized by the reduction of acenaphthylene in THF with the lanthanum(iii) complex [LaI₂(THF)₃]₂(₂-C₁₀H₈) containing the naphthalene dianion. The ¹H NMR spectrum of complex 2 in THF-d₈ exhibits four signals of the acenaphthylene dianion, whose strong upfield shifts compared to those of free acenaphthylene indicate the dianionic character of the ligand. The highest upfield chemical shift belongs to the proton bound to the C atom on which, according to calculation, the maximum negative charge is concentrated.     

Synthesis and crystal structure of [(η3-C3H5)(CO)2Mo(μ-S2CPCy3)-Mo(η3-CH2CMeCH2)(CO)2]

A novel dimolybdenum complex [(³-C₃H₅)(CO)₂Mo(-S₂CPCy₃)Mo(³-CH₂CMeCH₂)(CO)₂], obtained by reacting the [(CO)₂(³-C₃H₅)Mo(-S₂CPCy₃)Mo(CO)₃]^– anion with an excess of ClCH₂CMe=CH₂, has been characterized by i.r., ³¹P{¹H}, ¹H- and ¹³C-n.m.r. spectroscopy and by elemental analysis. The crystal structure of the complex, determined by X-ray diffraction, shows a definite preference for the central carbon of the S₂CPCy₃ bridge to bind to the Mo(2) atom coordinated by ³-2-methylallyl, rather than the Mo(1) atom attached to unsubstituted ³-allyl ligand.     

Crystal and molecular structure of (μ-η2,η3-propargyl)- bis(cyclopentadienyl)tetracarbonyldimolybdenum tetrafluoroborate and (μ-η2,η3-1,1-dimethylpropargyl)- bis(cyclopentadienyl)tetracarbonyldimolybdenum tetrafluoroborate

An X-ray study of [(μ-η²,η³-HCCCH₂)Cp₂Mo₂(CO)₄]⁺(BF₄⁻) (1) and [(μ-η²,η³-HCCCMe₂)Cp₂Mo₂(CO)₄]⁺(BF₄⁻) (2) reveals their structures to be similar to the structure of neutral compounds of the series (μ-η²,η²-RCCR)Cp₂Mo₂(CO)₄, the difference between 1 and 2 being mainly due to the markedly different MoC⁺ bond lengths, which accounts for different stability and fluxional behavior of these compounds in solution.     

Synthesis and reactivity of (μ-η2:η2-peroxo)dicopper(II) complexes with dinucleating ligands: Hydroxylation of xylyl linker with a NIH shift

New hexadentate dinucleating ligands having a xylyl linker, X–L–R, were synthesized, where X–L–R = 1,3-bis[bis(6-methyl-2-pyridylmethyl)aminomethyl]-2,4,6-trimethybenzene (Me₂–L–Me) and 1,3-bis[bis(6-methyl-2-pyridylmethyl)aminomethyl]-2-fluorobenzene (H–L–F). They form dinuclear copper(I) complexes, [Cu₂(X–L–R)]²⁺ (Me₂–L–Me (1) and H–L–F (2)). The copper(I) complexes in acetone at −78 °C react with O₂ to produce intra- and intermolecular (μ-η²:η²-peroxo)dicopper(II) species depending on the concentrations of the complexes:  both complexes generate intramolecular (μ-η²:η²-peroxo)dicopper(II) species [Cu₂(O₂)(X–L–R)]²⁺ (1-O₂ and 2-O₂) at the concentrations below ∼5 mM, whereas at ∼60 mM, both complexes produce intermolecular (μ-η²:η²-peroxo)dicopper(II) species, which were confirmed by the electronic and resonance Raman spectroscopies.  The electronic spectrum of 1-O₂ in acetone at concentrations below ∼5 mM showed an absorption band at (λ_max = 442 nm, ε = 5600 M⁻¹ cm⁻¹) assignable to the ${\mathrm{\pi }}_{\sigma }^1$(O–O)-to-Cu(II) ($({\text{d}}_{x^2-y^2}+{\text{d}}_{x^2-y^2})$ component) LMCT transition in addition to an intense band attributable to the ${\mathrm{\pi }}_{\sigma }^1$(O–O)-to-Cu(II) ($({\text{d}}_{x^2-y^2}-{\text{d}}_{x^2-y^2})$ component) LMCT transition (λ_max = 359 nm, ε = 21000 M⁻¹ cm⁻¹), indicating that the (μ-η²:η²-peroxo)Cu(II)₂ core of 1-O₂ takes a butterfly structure. Decomposition of 1-O₂ resulted in hydroxylation of the 2-position of the xylyl linker with 1,2-methyl migration (NIH shift), suggesting that the hydroxylation reaction proceeds via a cationic intermediate as proposed for closely related (μ-η²:η²-peroxo)Cu(II)₂ complexes having a xylyl linker. Kinetic study of the decomposition (hydroxylation of the xylyl linker) of 1-O₂ suggests that a stereochemical effect of the methyl group in the 2-position of the xylyl linker has a significant influence on a transition state for decomposition (hydroxylation of the xylyl linker).     

Synthesis and crystal structure of platinum(II) acetamidates [Pt(2,2′-bipy)(NHCOCH3)2] and [enPt(μ-NHCOCH3)(μ-OH)Pten](NO3)2

The diamines PtbipyCl₂, and PtenCl₂ and their aqua and hydroxy derivatives react with acetonitrile to give the Pt(II) acetamidates [Pt(2,2′-bipy)(NHCOCH₃)₂] · 4.125 H₂O (I) and [enPt(μ-NHCOCH₃(μ-OH)Pten](NO₃)₂ · H₂O (II), which are characterized by X-ray diffraction. The crystals of I are triclinic, a = 7.137(10) Å, b = 12.655(3) Å, c = 21.914(6) Å, α = 81.82(2)°, β = 82.12(2)°, γ = 77.72(2)°, V = 1908.6(7) ų, space group P $\overline 1 $ , Z = 4, R = 0.033 for 3700 reflections. Complex I is a mononuclear acetamidate with terminal (NHCOCH₃)^? ligands. The crystals of II are monoclinic, a = 11.413(2) Å, b = 10.981(2) Å, c = 14.385(3) Å, β = 105.90(3)°, V = 1733.8(6) ų, space group P2₁/n, R = 0.028 for 2797 reflections. Complex II is a dimer with bridging (NHCOCH₃)^? and (OH)^? groups. The Pt-Pt distance is 3.1667(7) Å.     

Comparison of the Bonding of Benzene and C60 to a Metal Cluster: Ru3(CO)9(μ3-η2,η 2,η2-C6H6) and Ru3(CO)9(μ3-η2,η2,η2-C60)

The electron distributions and bonding in Ru₃(CO)₉(³-²,²,²-C₆H₆) and Ru₃(CO)₉(³-²,²,²-C₆₀) are examined via electronic structure calculations in order to compare the nature of ligation of benzene and buckminsterfullerene to the common Ru₃(CO)₉ inorganic cluster. A fragment orbital approach, which is aided by the relatively high symmetry that these molecules possess, reveals important features of the electronic structures of these two systems. Reported crystal structures show that both benzene and C₆₀ are geometrically distorted when bound to the metal cluster fragment, and our ab initio calculations indicate that the energies of these distortions are similar. The experimental Ru–C_fullerene bond lengths are shorter than the corresponding Ru–C_benzene distances and the Ru–Ru bond lengths are longer in the fullerene-bound cluster than for the benzene-ligated cluster. Also, the carbonyl stretching frequencies are slightly higher for Ru₃(CO)₉(³-²,²,²-C₆₀) than for Ru₃(CO)₉(³-²,²,²-C₆H₆). As a whole, these observations suggest that electron density is being pulled away from the metal centers and CO ligands to form stronger Ru–C_fullerene than Ru–C_benzene bonds. Fenske-Hall molecular orbital calculations show that an important interaction is donation of electron density in the metal–metal bonds to empty orbitals of C₆₀ and C₆H₆. Bonds to the metal cluster that result from this interaction are the second highest occupied orbitals of both systems. A larger amount of density is donated to C₆₀ than to C₆H₆, thus accounting for the longer metal–metal bonds in the fullerene-bound cluster. The principal metal–arene bonding modes are the same in both systems, but the more band-like electronic structure of the fullerene (i.e., the greater number density of donor and acceptor orbitals in a given energy region) as compared to C₆H₆ permits a greater degree of electron flow and stronger bonding between the Ru₃(CO)₉ and C₆₀ fragments. Of significance to the reduction chemistry of M₃(CO)₉(³-²,²,²-C₆₀) molecules, the HOMO is largely localized on the metal–carbonyl fragment and the LUMO is largely localized on the C₆₀ portion of the molecule. The localized C₆₀ character of the LUMO is consistent with the similarity of the first two reductions of this class of molecules to the first two reductions of free C₆₀. The set of orbitals above the LUMO shows partial delocalization (in an antibonding sense) to the metal fragment, thus accounting for the relative ease of the third reduction of this class of molecules compared to the third reduction of free C₆₀.     

Synthesis and crystal structure of [Cu3(μ3-η1-CCPh)(μ-dppm)3][BF4]2, a tricopper(I) complex containing a μ3-η1 acetylide group and three bis(diphenylphosphino)methane (dppm) bridging ligands

The synthesis of the cationic trinuclear copper(I) complex [Cu₃(CCPh)(dppm)₃][BF₄]₂ is described. An X-ray structure determination shows a triangular array of copper atoms with three diphosphine ligands Ph₂PCH₂PPh₂ (dppm) bridging each edge of the triangle and a μ₃-η¹ phenyl acetylide group bound to the Cu₃ unit.     

The chemistry of pyridinethiols and related ligands,Part 9. Synthesis,spectroscopy and crystal structure of sulphur bridged dimeric [{η3-(O-μ-S)-1-oxopyridine-2-thione}(triphenylphosp hine)silver(I)]

Reaction of 1-hydroxypyridine-2-thione (HpyOS) in CHCl3 with Ag2CO3 suspended in CHCl3 under magnetic stirring followed by addition of PPh3 yields a product of stoichiometry: Ag(pyOS)(PPh3). The compound adopts a dimeric structure [Ag(pyOS)(PPh3)]2 (1) where each Ag atom acquires a distorted tetrahedral geometry by co-ordinating to one oxygen, two sulphur and one phosphorus atoms. The Ag2S2 core forms a parallelogram [Ag—S 2.507(1), 2.822(1)Å] with Ag—S—Ag and S—Ag—S angles of 74.8(1) and 105.2(1)°, respectively.     

Molecular structure of a new palladium-containing vinylidene cluster [η2-Ph2P(CH2)3PPh2]PdFe3(μ4-C=CHPh)(CO)9

The structure of the vinylidene cluster [²-Ph₂P(CH₂)₃PPh₂]PdFe₃(₄-C=CHPh)(CO)₉ was established by X-ray diffraction analysis. The metal core of the molecule has a butterfly shape with the Pd atom occupying a wingtip position. The C(1)=C(2)HPh ligand is -bound to three atoms of the Fe₂Pd triangle through the C(1) atom and is ²-coordinated to the Fe atom located in the second wingtip position via the C(1)=C(2) double bond. The Pd atom is chelated by the diphosphine ligand.     

Reactions of Ph3Sb═S with copper(I) complexes supported by N-donor ligands: formation of stable adducts and S-transfer reactivity

In the exploration of sulfur-delivery reagents useful for synthesizing models of the tetracopper-sulfide cluster of nitrous oxide reductase, reactions of Ph(3)Sb═S with Cu(I) complexes of N,N,N',N'-tetramethyl-2R,3R-cyclohexanediamine (TMCHD) and 1,4,7-trialkyltriazacyclononanes (R(3)tacn; R = Me, Et, iPr) were studied. Treatment of [(R(3)tacn)Cu(NCCH(3))]SbF(6) (R = Me, Et, or iPr) with 1 equiv of S═SbPh(3) in CH(2)Cl(2) yielded adducts [(R(3)tacn)Cu(S═SbPh(3))]SbF(6) (1-3), which were fully characterized, including by X-ray crystallography. The adducts slowly decayed to [(R(3)tacn)(2)Cu(2)(μ-η(2):η(2)-S(2))](2+) species (4-6) and SbPh(3), or more quickly in the presence of additional [(R(3)tacn)Cu(NCCH(3))]SbF(6) to 4-6 and [(R(3)tacn)Cu(SbPh(3))]SbF(6) (7-9). The results of mechanistic studies of the latter process were consistent with rapid intermolecular exchange of S═SbPh(3) between 1-3 and added [(R(3)tacn)Cu(NCCH(3))]SbF(6), followed by conversion to product via a dicopper intermediate formed in a rapid pre-equilibrium step. Key evidence supporting this step came from the observation of saturation behavior in a plot of the initial rate of loss of 1 versus the initial concentration of [(Me(3)tacn)Cu(NCCH(3))]SbF(6). Also, treatment of [(TMCHD)Cu(CH(3)CN)]PF(6) with S═SbPh(3) led to the known tricopper cluster [(TMCHD)(3)Cu(3)(μ(3)-S)(2)](PF(6))(3) in good yield (79%), a synthetic procedure superior to that previously reported (Brown, E. C.; York, J. T.; Antholine, W. E.; Ruiz, E.; Alvarez, S.; Tolman, W. B. J. Am. Chem. Soc. 2005, 127, 13752-13753).     

Synthesis and characterization of binuclear palladium complexes of isocyanides with novel bridging η3-indenyl ligands. Crytal structure of [Pd2(μ-η3-indenyl)2(RNC)2] (R = 2,6-dimethylphenyl)

The reaction of PdCl₂(RNC)₂ (RNC = isocyanide) with indenyl lithium (InLi) gave a binuclear palladium complex, [Pd₂(μ-η³-In)₂(RNC)₂], in which the Pd₂(RNC)₂ unit is sandwiched between two μ-η³-indenyl groups in a syn arrangement.     

Synthesis,molecular structure and spectroscopic characterization of MO(CO)2I2 (η2-dppm)(η1-dppm)

A new, high-yield method has been developed for the preparation of MO(CO)₂I₂(η²-dppm)(η¹-dppm). The title compound was prepared by the reaction of [Et₄N][Mo(CO)₄I₃] with dppm in benzene in 95% yield. It has been characterized by a single-crystal X-ray study. The crystallographic data are as follows: monoclinic, space group P2₁/n, a = 19.023(4) Å, b = 14.439(3) Å, c = 20.141(5) Å, β = 100.45(2)°, V = 5440(2) ų Z = 4. The geometry around the central metal atom could be considered as either a distortion from a capped octahedron with a carbonyl in a capping position or from a trigonal prism with the iodine capping a rectangular face. The solution behavior of Mo(CO)₂I₂(dppm)₂ was examined with ³¹P NMR, which showed it to be fluxional.     

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)×.     

Synthesis of Platinum-Triruthenium Clusters Using the Zero-Valent Platinum Reagent Pt(nb)3: X-Ray Crystal Structures of Ru3Pt(CO)11(P-iPr3)2, Ru3Pt(μ-H)(μ3-η3-MeCCHCMe)(CO)9(P-iPr3), Ru3Pt(μ3-η2-PhCCPh)(CO)10(P-iPr3), Ru3Pt(μ-H)(μ4-N)(CO)10(P-iPr3) and Ru3Pt(μ-H)(μ4-η2-NO)(CO)10(P-iPr3)

The complexes Pt(nb)_3-n(P-iPr₃)_n (n=1, 2, nb=bicyclo[2.2.1]hept-2-ene), prepared in situ from Pt(nb)₃, are useful reagents for addition of Pt(P-iPr₃)_n fragments to saturated triruthenium clusters. The complexes Ru₃Pt(CO)₁₁(P-iPr₃)₂ (1), Ru₃Pt(-H)(₃-³-MeCCHCMe)(CO)₉(P-iPr₃) (2), Ru₃Pt(₃-²-PhCCPh)(CO)₁₀(P-iPr₃) (3), Ru₃Pt(-H)(₄-N)(CO)₁₀(P-iPr₃) (4) and Ru₃Pt(-H)(₄-²-NO)(CO)₁₀(P-iPr₃) (5) have been prepared in this fashion. All complexes have been characterized spectroscopically and by single crystal X-ray determinations. Clusters 1–3 all have 60 cluster valence electrons (CVE) but exhibit differing metal skeletal geometries. Cluster 1 exhibits a planar-rhomboidal metal skeleton with 5 metal–metal bonds and with minor disorder in the metal atoms. Cluster 2 has a distorted tetrahedral metal arrangement, while cluster 3 has a butterfly framework (butterfly angle=118.93(2)°). Clusters 4 and 5 posseses 62 CVE and spiked triangular metal frameworks. Cluster 4 contains a ₄-nitrido ligand, while cluster 5 has a highly unusual ₄-²-nitrosyl ligand with a very long nitrosyl N–O distance of 1.366(5) Å.     

Cluster chemistry. 85. Addition of a gold acetylide to an Ru5 cluster. X-ray structure of AuRu5(μ5-C2PPh2)(μ-C2Ph)(μ-PPh2)(CO)13(PPh3)

The reaction between Ru₅(₅-C₂PPh₂)(-PPh₂)(CO)₁₃ and Au(C₂Ph)(PPh₃) afforded AuRu₅(₅-C₂PPh₂)(-C₂Ph)(-PPh₂)(CO)₁₃ (PPh₃), in which the Ru₅ cluster has a scorpion geometry; the Au(PPh₃) group bridges one of the Ru-Ru bonds of the Ru₃ triangle, while the C₂Ph group bridges one of the tail Ru-Ru vectors.For Part 84, see Ref. 1.     

Co3(CO)7(μ3-S)(μ,η2-SCNR2)的合成和晶体结构

Co2(CO)8与4个二硫代双(烷基硫代甲酰胺)类前配体[R2NC(S)S]2反应,得4个含烷基硫代甲酰胺基的三核钴羰基硫簇合物.通过元素分析、IR、1H NMR和MS等方法表征了它们的结构,用X射线衍射法测定了其中一个簇合物Co3(CO)7(μ3-S)[μ,η2-SCN(i-Pr)2](Ⅲ)的晶体结构.晶体属单斜晶系,P21/n空间群,晶胞参数a=1.145 2(2)nm,b=1.502 8(3)nm,c=1.2144(2)nm,a=90°,β=92.15(3)°,γ=90°,V=2.088 5(7)nm3,Z=4,F(000)=1 096,Dc=1.747 mg·m-3,GOF(F2)=0.835,μ=2.588 nm-1.最终因子R[I＞2σ(I)]=0.040 7,Rw=0.062 4.     

Cluster chemistry. Synthesis and X-ray structure of Os5(μ5-η2,P-C2PPh2)(μ-PPh2)(CO)13, a complex containing a phosphinoalkylne ligand attached to an open Os5 cluster

Reaction of C₂(PPh₂)₂(dppa) with Os₃(CO)₁₁(NCMe) affords the yellow complex [Os₃(CO)₁₁]₂(μ-dppa); this on heating gives [Os₅(μ₅-η²-P-C₂PPh₂)(μ-PPh₂)(CO)₁₃] in 51% yield, which is shown by an X-ray study to contain a seven electron donor C₂PPh₂ ligand interacting with all five Os₅ atoms of an open Os₅ cluster consisting of three edge fused Os₃ triangles with a “swallowlike” arrangement. The PPh₂ group bridges the non fused edgeof the central triangle. The structure appears to be identical with that described for the equivalent ruthenium complex.