Synthesis and Characterization of Tetrametal Cluster [Co2(CO)6][μ-HC2CH2OCH2C2H-μ][Co2(CO)6]

The treatment of dipropargyl ether HC2CH2OCH2C2H with Co2(CO)8 resulted in the formation of a novel cluster [Co2(CO)6][μ-HC2CH2OCH2C2H-μ][Co2(CO)6]. The cluster was characterized by C/H analyses, IR and 1H NMR spectroscopy and X-ray crystal structure determination. It belongs to monoclinic system, space group P21/c with the following crystallographic parameters: a=18.149(2), b=7.0111(7), c=20.897(2)(A), β=115.318(7)°, V=2403.7(5)(A)3, Z=4, Mr=665.97, Dc=1.840 g·cm-3, F(000)=1304.00, μ(Mo-Kα)=27.76 cm-1 and R=0.030 for 2372 observed reflections.     

Synthesis and Crystal Structure of Cluster [C6H4-1,2-(CO2CH2C2H-μ)2][Co2(CO)6]2

The reaction of dipropargyl phthalate C6H4-1,2-(CO2CH2C2H-μ)2 1 with octacarbonyldicobalt 2 resulted in the formation of red complex [C6H4-1,2-(CO2CH2C2H-μ)2][Co2(CO)6]2 3, in which each Co2(CO)6 group coordinates to one of the two C≡C bonds of 1. Molecular structure of complex 3 was determined by single crystal X-ray analyses. The crystal belongs to the monoclinic system, space group P21/a with the following crystallographic parameters: a=8.521(2), b=29.143(6), c=12.918(7)(A), β= 100.12(3)°, V=3158(2)(A)3, Z=4, Mr=814.09, Dc=1.712 g.cm-3, F(000)=1608, μ(Mo-Kα)=21.37 cm-1 and final R=0.044 for 3151 observations.     

The unusual electrochemical behaviour of [Co8(CO)18C]2− compared to [M6(CO)15C]2− (M = Co,Rh) and [Fe6(CO)16C]2− carbido clusters

A variety of electrochemical reactions has been observed for the carbido-carbonyl clusters [Co₈(CO)₁₈C](NMe₃CH₂C₆H₅)₂, [Co₆(CO)₁₅C](NMe₃CH₂C₆H₅)₂, [Rh₆(CO)₁₅C](Et₄N)₂ and [Fe₆(CO)₁₆C](Et₄N)₂. The hexanuclear clusters undergo irreversible electrochemical oxidation and reduction steps, whereas the octacobalt species exhibits three electrochemically reversible one-electron steps. The relation between the redox properties and the structure of these clusters is discussed.     

Co-ordination of copper and silver by [Co2{μ-C2(CH2SCH2CH2)2S}(CO)6]

The thiamacrocycle [Co₂{μ-C₂(CH₂SCH₂CH₂)₂S}(CO)₆] reacts with Ag[BF₄] and PPh₃ to afford the fluxional compound [Co₂{μ-C₂(CH₂SCH₂)₂S}(CO)₆(AgPPh₃)][BF₄], the structure of which has been established by X-ray crystallography, and with [Cu(CH₃₋CN)₄][PF₆] to afford [Co₂{μ-C₂(CH₂SCH₂CH₂)₂S}(CO)₆(CuCH₃₋CN)][PF₆], which undergoes phosphine sustitution.     

Synthesis, molecular structures, and properties of heterometallic cobalt tetramethylcyclobutadiene complexes (C4Me4)Co(CO)2TePh, (C4Me4)Co(CO)2TePh[W(CO)5], and Me4C4Co(μ3-S)2Cr2Cp2(μ-SC4H9)

The reaction of Cb*Co(CO)₂I (1) (Cb* is tetramethylcyclobutadiene) with sodium phenyltelluride afforded the mononuclesar complex Cb*Co(CO)₂TePh (2). The reaction of the latter with W(CO)₅(THF) produced the Cb*Co(CO)₂TePh[W(CO)₅] compound (4). The reaction of 1 with the Cp₂Cr₂(SCMe₃)₂S complex gave the heterometallic cluster Cb*Co(μ₃-S)₂Cr₂Cp2 (μ-SCMe₃) (5). Complexes 2, 4, and 5 are diamagnetic. Their structures were determined by X-ray diffraction. Complex 2 contains the Co-Te bond (2.585(1) Å); complex 4, the Co-Te (2.558(8) Å) and W-Te (2.8467(6) Å) bonds. Complex 5 has the stable triangular sulfide-and tert-butylmercaptide-bridged core Cr₂Co (Cr-Cr and Cr-Co bond lengths are 2.626(2) and 2.673(2) Å, respectively) with Cp ligands at the chromium atoms and a Cb* ligand at the cobalt atom. Complex 5 was characterized by cyclic voltammetry. The thermolysis of complex 4 was studied.     

Synthesis,Crystal and Molecular Structures of [Co(MH)2(Thio)2][BF4] · H2O and [Co(DH)2(NH3)2][BF4]

Crystal structures of [Co(MH)₂(Thio)₂][BF₄] · H₂O (I) and [Co(DH)₂(NH₃)₂][BF₄] (II), where MH^– is H₃C–C(NOH)–C(NO^–)–H and DH^– is H₃C–C(NOH)–C(NO^–)–CH₃, were determined by X-ray diffraction. The crystals are monoclinic, space group C2/c, unit cell parameters (for I and II, respectively): a = 22.018(2) Å, b = 7.943(1) Å, c = 11.681(1) Å, = 92.68(1)° and a = 21.436(2) Å, b = 6.400(2) Å, c = 12.389(2) Å, = 113.13(1)°. In both cases, the Co(III) coordination polyhedron is a centrosymmetrical trans-octahedron, N₄S₂ for I and N₆ for II. In the crystals of I and II, the complex cations and the outer-sphere [BF₄]^– anions (and the crystal water molecules in I) form elaborate hydrogen bonding system.     

The preparation and structure of the tetranuclear ruthenium cluster [Ru4(CO)10(μ2-Cl)2(μ3-OEt)2]

The tetranuclear ruthenium cluster [Ru₄(CO)₁₀Cl₂(OEt)₂] has been prepared in low yield by the reaction of [Ru₃(CO)₁₂] with [N(PPh₃)₂]Cl in refluxing EtOH, followed by oxidation with either [NO][BF₄] or Ag[ClO₄]. A single-crystal X-ray analysis of the complex shows that the four metal atoms adopt a planar geometry with one ruthenium bonded by two μ₂-Cl ligands and two μ₃-OEt ligands to a trinuclear fragment. This complex crystallises in the monoclinic space group I2/c, with a 14.458(3), b 22.073(6), c 15.302(4) Å, β 99.54(2)°, Z = 8; 3113 observed data with F > 3σ(F) were refined by blocked full-matrix least squares to R = 0.031, R_w = 0.034.     

Tetracarbonyliron adducts of Cp2Cr2(CO)4(μ-η2-P2). Syntheses and crystal structures of Cp2Cr2(CO)4P2[Fe(CO)4] m (m=1 and 2)

Cp₂Cr₂(CO)₄( - ² - P₂), 1, reacts with one molar equivalent of Fe₂(CO)₉ in THF to yield the mono- and di-iron complexes, Cp₂Cr₂(CO)₄P₂[Fe(CO)₄], 2, (16.5% yield) and Cp₂Cr₂(CO)₄P₂[Fe(CO)₄]₂, 3, (16.9% yield), as dark magenta brown and dark greenish brown crystals, respectively. Both complexes were characterized by single-crystal X-ray diffraction analysis. Crystal data –2: space group =P2₁/c,a=17.024(1) Å,b=8.180(1) Å,c=30.891(2) Å, =100.953(5)°,V=4223.4(7)ų,Z=8, 3743 observed reflections,R _F=0.033; 3: space group P1,a=10.209(2) Å,b=10.212(2) Å,c=15.989(3) Å, =106.93(1)°, =91.87(1)°, =119.50(1)°,V=1356.5(4) ų,Z=2, 3489 observed reflections,R _F=0.029.     

Synthesis and characterisation of novel selenium-containing clusters; crystal structures of [Ru4(μ4-Se)2(CO)8(μ-CO)3] and [Ru3(μ3-Se)2(CO)7(Ph2P(CH2)3PPh2)]

The compound [Ru₄(μ-Se)₂(CO)₈(μ3-CO)₃] (1), has been obtained in good yield by vacuum pyrolysis of [RU₃(CO)₁₂] with [Ph₂Se₂] at 185°C. Reaction of 1 with 1,3-bis(diphenylphosphino)propane at room temperature affords the novel cluster [RU₃(μ₃-Se)₂(CO)₇(Ph₂P(CH₂)₃PPh₂)] (2). The structures of 1 and 2 have been determined by an X-ray diffraction study.     

Synthesis and structures of new heterometallic clusters [Fe2(MCp x )(CO)6(μ3-S)2] (M = Rh, Ir; Cp x = Cp*, C5H3But 2)

The reaction of the [Fe₂(CO)₆(μ-S)₂]^2? anion (prepared in situ by reduction of [Fe₂(CO)₆(μ-S₂)] with Na/K alloy) with [Cp″RhCl₂]₂ (Cp″ = η⁵-(1,3-Bu^t ₂)C₅H₃) and [Cp*Ir(CH₃CN)₃](CF₃SO₃)₂ (Cp^* is pentamethylcyclopentadienide) yielded new heterometallic clusters [Fe₂(MCp ^x )(CO)₆(μ₃-S)₂]. The core of the resulting clusters can be described as the distorted [Fe₂S₂M] square pyramid with the M atom in the apical position. The structures of the clusters were established by X-ray diffraction.     

[μ4-SiCo(CO)4]2Co4(CO)11, a cobalt carbonyl cluster incorporating five-coordinate silicon

Si₂H₆ reacts with Co₂(CO)₈ to form Si₂Co₆(CO)₁₉, shown by X-ray structure analysis to contain a pseudo-octahedral trans-Si₂Co₄ core with terminal Co(CO)₄ groups on the silicon atoms. This is the first silicon example of a compound with the E₂M₄ type with M = transition metal and E = main group element, and has the silicon in a distorted square-pyramidal configuraion, with a Si...Si distance of 2.817 Å.     

X-ray structural study of the first bicluster π-arene complex [η6-PhCo4(CO)9]2CH2 and binuclear complex [η6-PhCr(CO)3]2CH2

It has been established by X-ray structural study that the bicluster cobalt -arene complex of diphenylmethane [⁶-PhCo₄CO₉]₂CH₂ and binuclear complex [⁶-PhCr(CO)₃]₂CH₂ have ans-trans-s-trans conformation in their crystals.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1111–1117, June, 1995.This work was supported by the Russian Foundation for Basic Research (Projects No. 93-03-4028 and 94-03-08338).     

Synthesis and Crystal Structure of[Co3(CO)9(μ3-C)C(O)OCH2]2

The title compound [Co3(CO)9(μ3-C)C(O)OCH2]2 was synthesized by the reaction of [Cl3CC(O)OCH2]2 with Co2(CO)8 at 40～50 ℃. Crystal data: C24H4O22Co6, Mr=997.88, monoclinic, space group P21/n(#14), a=9.330(2), b=15.197(4), c=11.783(4), β=91.16(2)°, V=1670.4(7) 3, Z=2, Dc=1.984 g/cm3, μ(MoKα)=30.01 cm-1, F(000)=972.00, T=293K, final R=0.045, Rw=0.051 for 1936 observed reflections with I＞2σ(I). The structure contains two centrosymmetric dimeric molecules in a unit cell, each of which has two tetrahedral skeletons (CCo3) connected through a C(O)OCH3CH2OC(O) bridge.     

Synthesis and characterisation of hexanuclear ruthenium clusters containing a μ4-nitrene ligand. Crystal structures of [Ru6(CO)15(μ-CO)2(μ4NH)(μ-OMe)μ3-η2-N(H)C(O)OMe] and [Ru6(CO)16(μ-CO)2(μ4-NH)(μ-OMe)(μ-NCO)]

Two hexaruthenium carbonyl clusters [Ru₆(CO)₁₅(μ-CO)₂(μ₄-NH) (μ-OMe){μ₃-η²-N(H)C(O)OMe}] and [Ru₆(CO)₁₆(μ-CO)₂-(μ₄-NH)(μ-OMe)(μ-NCO)]2 have been isolated from the pyrolysis of H₂Ru₃(CO))₉NOCH₃, and single-crystal X-ray structure analysis shows that both 1 and 2 have a square planar arrangement of four ruthenium atoms capped by a μ₄-nitrene ligand, with two additional ruthenium atoms bridging two opposite RuRu edges of the square base to form a ‘boat’ form metal framework.     

Synthesis and characterization of linked alkyne-bridging Co2C2 tetrahedral clusters and expansion reactions of (Co2(CO)6(μ-HCCCH2OOC))2R with Fe3(CO)12

Two new linked alkyne-bridging tetrahedral carbonyl clusters containing Co₂C₂ Co₂(CO)₆(μ-HCCCH₂OOC(CH₂)₃COOCH₂CCH-μ)Co₂(CO)₆, 1, and Co₂(CO)₆(μ-HCCCH₂OOC(CH₂)₈COOCH₂CCH-μ)Co₂(CO)₆, 2, have been prepared by reactions of two dipropargyl esters (HC≡CCH₂OOC)₂R (R = (CH₂)₃, (CH₂)₈) with Co₂(CO)₈. Expansion reactions of 1 and Co₂(CO)₆(μ-HCCCH₂OOCCOOCH₂CCH-μ)Co₂(CO)₆, 3, with Fe₃(CO)₁₂ give two new mixed-metal linked clusters Co₂(CO)₆(μ-HCCCH₂OOC(CH₂)₃COOCH₂CCH-μ,η⁴)Co₂Fe₂(CO)₁₂, 4, and Co₂(CO)₆(μ-HCCCH₂OOCCOOCH₂CCH-μ,η⁴)Co₂Fe₂(CO)₁₂, 5. The new clusters were characterized by elemental analysis, IR, ¹H-NMR and ESI-MS analysis.     

Reactions of carbonyl clusters with potentially tridentate thioethers: Crystal and molecular structures of [Os4(CO) 13([12]aneS3)] and [Ru6(CO)15(μ4-η2- CO)([12]aneS3)] [([12]aneS3) = {(CH2) 3S}3]

The reaction of [Os₃(CO)₁₂ with [12]aneS₃ ([12]aneS₃  {(CH₂)₃S}₃) in octane for 6 h, under reflux, led to isolation of two products [Os₃(CO)₁₁([12]aneS₃)] (1) and [Os₄(CO) ₁₃([12]aneS₃)] (2), while with [Ru₃(CO)₁₂] under similar conditions, in THF, a number of products were obtained, including [Ru₄(CO)₁₁([12]aneS₃)] (3), [Ru₅(CO)₁₃([12]aneS₃)] (4), and [Ru₆(CO)₁₆([12]aneS₃)] (5). An X-ray diffraction study of 2 shows that the macrocycle is coordinated to the ‘wingtips’ of an Os₄ butterfly through the two electron pairs on one sulphur atom, while in 5 all three sulphur atoms of the macrocycle coordinate to two of the Ru atoms in a spiked edge-bridged tetrahedral metal framework.     

[Co^I(CO)(dppe-P,P')2]2[Co2^I^I(μ-dppeo)Cl6].2CH3OH的合成和结构

合成了混合价态多核羰基钴离子对配合物[Co^I/(CO)(dppe-P,P')2]2[co2^I^I(μ-dppeo)Cl6]{dppeo=双二苯基膦基乙烷Ph2P(O)CH2CH2P(O)Ph2},用X射线衍射法测定了其晶体学参数为a=11.761(3),b=12.860(2), c=21.428(3)A, a=81.45(2), β=82.47(2), γ=79.84(2)°, 三斜晶系, PI空间群, Co^I和Co^I^I具有不同的配位构型, 量子化学计算结果解释了该配合物稳定的原因。     

The first decaruthenium hydrido cluster: synthesis and crystal structure of [N(PPh3)2]2[Ru10C(CO)24]·C6H14 and [N(PPh3)2][HRu10C(CO)24]

X-ray structural studies of new thermolysis products from the reaction of Ru₃(CO)₁₂ in heptane in the presence of 1,3,5-trimethylbenzene (mesitylene) confirm that they are the decaruthenium carbido-cluster dianion [Ru₁₀C(CO)₂₄]²⁻ (I) and the hydrido decaruthenium carbido-cluster monoanion [HRu₁₀C(CO)₂₄]⁻ (II). Both anions have the giant tetrahedron Ru₁₀ metal framework, and the monohydride provides the first example of a hydrido ligand in a tetrahedral Ru₄ cavity.     

Synthesis, Characterization and Crystal Structure of [Co2Mo2(μ4-C2HPh)(μ-CO)4(CO)4(η5-C5H4C(O)Me)2]

The reaction of μ-alkyne-bridged dimolybdenum compound [Mo2(μ-C2HPh)(CO)4(η5-C5H4C(O)Me)2] 1 with Co2(CO)8 in refluxing toluene gave a new butterfly compound [Co2Mo2(μ4-C2HPh)(μ-CO)4(CO)4(η5-C5H4C(O)Me)2] 2 which was fully characterized by elemental analysis, IR, 1H NMR and X-ray single crystal diffraction techniques. 2 crystallized in monoclinic system, C30H20Co2Mo2O10, Mr=850.23, space group P21/a(#14), a=14.165(5), b=12.498(2), c=16.204(2)(A), β = 96.50(2)°, V = 2850(1)(A)3, Z = 4, Dc = 1.981 g cm-3, F(000)=1672, μ(MoKα)=20.41 cm-1, final R=0.030, Rw=0.039 for 4831 observable reflections with I>2σ(I). The structure contains a Co2Mo2 butterfly core, and each Mo-Co bond is spanned by an asymmetric semi-bridging carbonyl ligand.