The preparation of a series of ring-linked derivatives of [Fe2(η-C5H5)2(CO)2(μ-CO)2] starting from [Fe2η5,η5-C5H4CH(NMe3)CH(NMe2)C5H4}(CO)2(μ-CO)2]+ salts

The salts [Fe₂η⁵,η⁵-C₅H₄CH{NMe₃)CH(NMe₂)C₅H₄}(CO)₂(μ-CO)₂][X] (X = I or SO₃CF₃) are the synthetic precursors to a wide range of [Fe₂(η-C₅H₅)₂(CO)₂(μ-CO)₂] derivatives in which the two cyclopentadienyl ligands are joined by a two-carbon bridge.     

Reactions of dipropargyl manolate,terephthalate with Co2(CO)8, Mo2Cp2(CO)4 and RuCo2(CO)11 give the di or tetranuclear clusters. The crystal structure of [CH2(CO2CH2C2H-μ)2][Co2(CO)6]2 and [p-(HC2CH2OCO)C6H4(CO2CH2C2H-μ)][Co2(CO)6]

The reactions of dipropargyl manolate and terephthalate, respectively, with Co₂(CO)₈ in THF at room temperature gave four new compounds [R(CO₂CH₂C₂H-μ)₂][Co₂(CO)₆]₂ (R=CH₂, 1a; R=C₆H₄, 1b) and [(HC₂CH₂OCO)R(CO₂CH₂C₂H-μ)][Co₂(CO)₆] (R=CH₂, 2a; R=C₆H₄-1,4-, 2b), and compounds 2a and b reacted with RuCo₂(CO)₁₁ to form two new linked clusters [R(CO₂CH₂C₂H-μ)₂][Co₂(CO)₆][RuCo₂(CO)₉] (R=CH₂, 3a; R=C₆H₄-1,4-, 3b). The treatment of two dipropargyl esters, respectively, with RuCo₂(CO)₁₁ afforded another two new clusters [R(CO₂CH₂C₂H-μ)₂][RuCo₂(CO)₉]₂ (R=CH₂, 4a; R=C₆H₄-1,4-, 4b). The reactions of dipropargyl manolate, terephalate with Mo₂Cp₂(CO)₄ gave rise to the formation of dinuclear complexes [(HC₂CH₂OCO)R(CO₂CH₂C₂H-μ)][Mo₂Cp₂(CO)₄] (R=CH₂, 5a; R=C₆H₄-1,4-, 5b), compound 5a reacted with Co₂(CO)₈ to produce the cluster [CH₂(CO₂CH₂C₂H-μ)₂][Co₂(CO)₆][Mo₂Cp₂(CO)₄] 6a. All the new clusters have been characterized by C/H elemental analysis, IR and ¹H NMR spectroscopies. The structure of [CH₂(CO₂CH₂C₂H-μ)₂][Co₂(CO)₆]₂ 1a and [p-(HC₂CH₂OCO)C₆H₄(CO₂CH₂C₂H-μ)][Co₂(CO)₆] 2b have been determined by single crystal X-ray diffraction methods.     

Conformational analysis and x-ray crystal structure of [(η5-C5H5)Fe(CO)(PPh3)CH2CH3]

The complex [(η⁵-C₅H₅)Fe(CO)(PPh₃)CH₂CH₃] is shown by ¹H NMR spectroscopy and an X-ray crystal structure analysis to adopt a single conformation with the methyl group residing between the cyclopentadienyl and carbon monoxide ligands.     

Cluster Complexes of Polythioether Macrocycles: The Synthesis and Molecular Structures of Ru6(CO)13(cis-SCH2 CHMe(CH2SCH2CHMe)2CH2)(μ6-C) and Ru6(CO)13(trans-SCH2 CHMe(CH2SCH2CHMe)2CH2)(μ6-C)

The reaction of a mixture of cis-3,7,11-trimethyl-1,5,9-trithiacyclododecane, cis-Me₃12S3, 1 and trans-3,7,11-trimethyl-l,5,9-trithiacyclododecane, trans-Me₃12S3, 2, with Ru₆(CO)₁₇(μ ₆-C), 3, yielded three new cluster compounds Ru₆(CO)₁₃(μ-η³-cis-SCH₂CHMe(CH₂SCH₂CHMe)₂CH₂)(μ ₆-C) 4, and two isomers of Ru₆(CO)₁₃(μ-η³-cis-SCH₂CHMe(CH₂SCH₂CHMe)₂CH₂)(μ ₆-C) 5a and 5b. The molecular structures of 4 and 5b were established by single crystal X-ray diffraction analyses. In both complexes, the macrocycles have adopted tridentate coordination with one of the sulfur atoms in a bridging position. Two carbonyl ligands occupy bridging positions in each compound. Crystal Data for 4·Me₂CO: space group=P2₁/n, a=11.295(1) Å, b=17.547(3) Å, c=20.318(3) Å, β=93.71(1)°, Z=4, 2900 reflections, R=0.025. Crystal Data for 5b·1.5 C₆H₆: space group=Pbca, a=31.8900(8) Å, b=23.4330(6) Å, c=21.6240(4) Å, Z=16, 12163 reflections, R=0.040.     

Efficient Diastereoselective Synthesis of Chiral Diferrocenylphosphine‐diamines: X‐ray Crystal Structure of [(η5‐C5H5)Fe{(η5‐C5H3)PPh2CH(CH3) N(CH2)2(CH2)2NCH(CH3)PPh2 (η5‐C5H3)}Fe(η5‐C5H5)]

Abstract

Three novel chiral planar diferrocenylphosphine‐diamines 5 (a–c) were designed and synthesized starting with (s)‐(?)‐N,N‐dimethyl‐1‐ferrocenylethylamine‐1 [(S)‐1]. All new compounds were identified by ¹H NMR and MS. The structure of chiral diferrocenylphosphine‐diamine 5c was determined by X‐ray crystallography. Single crystal X‐ray diffraction analysis reveals that the molecular structure of compound 5c [(η⁵‐C₅H₅)Fe{(η⁵‐C₅H₃)PPh₂CH(CH₃) N(CH₂)₂(CH₂)₂NCH(CH₃)PPh₂‐(η⁵‐C₅H₃)}Fe(η⁵‐C₅H₅)] is enantiomerically pure and crystallizes in the noncentrosymmetric P2(1)2(1)2(1) space group; it maintains “Z” shape and contains a piperazine hexahydrate ring bridge. The piperazine ring adopts a favored chair conformation and the chiral center C₂₃ and C₂₉ substituents in S‐configuration.     

Insertion reactions of t-Bu(η5-C5H5)Fe(CO)2

The complex t-Bu(η⁵-C₅H₅)FE(CO)₂ has been treated with triphenylphosphine in refluxing THF to produce t-BuCO(η⁵-C₅H₅)Fe(CO)(PPh₃). The large steric bulk of the t-butyl group suggests that this reaction should be faster than the reaction involving the methyl group, and a kinetic investigation illustrates this to be the case. The same steric bulk predicts that the reaction with SO₂ should be slow, and indeed we have been unable to effect the related SO₂ insertion reaction. Attempts to prepare the corresponding t-Bu(η⁵-C₅H₅)W(CO)₃ led to formation of the related isobutyl complex.     

Crystal structure of twinned (η5-C5(CH3)4CF3) (η5-C5(CH3)5)Ru

The substituted sandwich complex crystallizes in monoclinic space groupP2₁/m withZ=2. Twinning to the (001) direction with the special conditionc ^*/4a ^* = cos ^* causes systematic superposition of the reciprocal lattices of both domains and results in an apparent unit cell with double volume and the reflection condition (2h)kl, l=2n. The structure solution was obtained with the subset of intensity data for the predominant individuum and converged atR = 0.040,R _w =0.046 for 832 independent observations and 122 variables. The molecules show disorder with respect to the crystallographic mirror plane. The structure is closely related to that of decamethylruthenocene.     

Tantalocene complexes as bidentate métalloligands: (C5Me5)(C5H4X)Ta(H2)(PPh2) (C5Me5) (C5H4X)Ta(CO) (PPh2) (X = PPh2, CH2CH2NMe2)

The synthesis of new bidentate métalloligands derived from tantalocene(C₅Me₅)(C₅H₄X)Ta(H₂)(PPh₂) (X = PPh₂, 2P; X = CH₂CH₂NMe₂2N) and (C₅Me₅)(C₅H₄X)Ta(CO)(PPh₂) 4(P,N) is described. When opposed to chromium unsaturated fragments the phosphino functionalised complexes 2P and 4P act as chelating bidentate ligands affording Ta(V) (C₅Me₅)(C₅H₄PPh₂)Ta(CH₂) (μ-PPh₂)Cr(CO)₄ or Ta(III) (C₅Me₅)(C₅H₄PPh₂)Ta(CO)(μ-PPh₂)Cr(CO)₄ bimetallic complexes. The same reaction carried out starting from 2N gives rise to a μ-phosphido, μ-hydrido dibridged complex Cp*(C₅H₄CH₂CH₂NMe₂)TaH(μ-H)(μ-PPh₂)Cr(CO)₄.     

Synthesis of the dimetal compounds [FeW{μ-PPh2 · CH · CH2 C(C6H4Me-4)}(CO)5(η5-C5Me5)] and [FeMo{μ-PPh2 · CH · CH2 · C(C6H4Me-4)}(CO)5(η5-C5H5)]; molecular structure of the iron-tungsten compound

Reactions between diphenyl(vinyl)phosphine and the compounds [FeW(μ-CC₆H₄Me-4)(CO)₅(η⁵-C₅Me₅)] and [FeMo(μ-CC₆H₄Me-4)(CO)₆(η⁵-C₅H₅)] result in a coupling of the vinyl and p-tolylmethylidyne groups at the dimetal centres to produce the PPh₂ · CH · CH₂ · C(C₆H₄Me-4) fragment, which bridges the metal-metal bonds. This was confirmed by an X-ray diffraction study on [FeW{μ-PPh₂ · CH · CH₂ · C(C₆H₄Me-4)}(CO)₅(η⁵-C₅Me₅)].     

Tetramethyl(2-methoxyethyl)cyclopentadienyl complexes of zirconium(iv). Crystal structure of [η5:η1−C5(CH3)4(CH2CH2OCH3)]ZrCl3

Several novel zirconium(iv) complexes with the chelating oxygen-containing cyclopentadienyl ligand, tetramethyl(2-methoxyethyl)cyclopentadiene, have been synthesized. [⁵:¹-Tetra-methyl(2-methyl)cyclopentadienyl]trichlorozirconium (2), bis[⁵-tetramethyl(2-methoxyethyl)cyclopentadienyl]dichlorozirconium (3), [⁵-pentamethylcyclopentadienyl][⁵-tetra-methyl(2-methoxyethyl)cyclopentadienyl]dichlorozirconium (4), and [⁵-tetra-methyl(2-methylthioethyl)cyclopentadienyl][⁵-tetramethyl(2-methoxyethyl)-cyclopentadienyl]dichlorozirconium (5) have been prepared from the corresponding lithium cyclopentadienide (l). The crystal structure of cyclopentadienyl complex2 has been established by X-ray analysis. The coordination OZr bond in compound2 exists both in the crystalline state and in solutions. No coordination of this type was observed in complexes3–5. Synthesized complexes2–5 are discussed in comparison with their sulfur-containing analogs.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1828–1832, July, 1996.     

New electron-deficient alkene and alkyne derivatives of Ru5(μ5-C)(CO)15: The syntheses and crystal structure analyses of Ru5(μ5-C)(CO)13 [C2H2(CO2Me)2] and Ru5(μ5-C)(CO)15 [C2(CO2Me)2]

Treatment of carbido cluster Ru₅(μ ₅-C)(CO)₁₅ with Me₃NO in acetonitrile solution followed by addition of dimethyl maleate or dimethyl acetylene dicarboxylate affords new clusters Ru₅(μ ₅-C)(CO)₁₃[C₂H₂(CO₂Me)₂] (1) and Ru₅(μ ₅-C)(CO)₁₅[C₂(CO₂Me)₂] (2), respectively. Single crystal X-ray structural studies reveal that both complexes contain a wingtip-bridged butterfly pentametallic skeleton. In complex1 the maleate fragment is coordinated to one wingtip Ru atom through its carbon-carbon double bond and to the adjacent Ru atom by the formation of two O → Ru dative bonding interactions, while the acetylene dicarboxylate fragment in2 is best considered as acis-dimetallated alkene, linking one hinge Ru atom and the nearby Ru atom at the bridged position. Crystal data for1: space group P 4₂/n;a=20.199(6),c=13.941(3) Å,Z=8; finalR _F=0.025,R _w=0.026 for 3963 reflections withI>2σ(I). Crystal data for2: space group P2₁/n;a=9.634(3),b=20.062(6),c=17.372(5) Å,β=90.62(2)°,Z=4; finalR _F=0 033,R _w=0.036 for 4683 reflections withI>3σ(I).     

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.     

Addition of boranes to (E)-(η5-C5H5)2Zr(CH=CHPh)Cl

In this study, the addition of boranes to (E)-(η⁵-C₅H₅)₂Zr(CH=CHPh)Cl (3) has been examined in order to investigate the regioselectivity of these ‘hydroboration’ reactions. We have found that these additions proceed with remarkable selectivity to give exclusive formation of a saturated organic molecule where one carbon atom has both the boron and the zirconium fragments. These reactions do not proceed via a conventional hydroboration reaction, but instead go through an initial transmetalation step to generate (E)-(η⁵-C₅H₅)₂Zr(H)Cl (1) and the corresponding alkenyl boron intermediate, whereupon subsequent hydrozirconation of this latter species gives the geminal products. An x-ray diffraction study has been conducted on gem-(η⁵-C₅H₅)₂Zr(CH(Bpin)CH₂Ph)Cl (pin = 1, 2-O₂C₂Me₄) (2). Crystals of 2 were orthorhombic with a = 18.545(3) Å, b = 15.713(3) Å, c = 16.157(3) Å in the space group Pccn. An x-ray diffraction study has also been conducted on the trinuclear zirconium oxide species (η⁵-C₅H₅)₂ZrO₂[ZrCl(η⁵-C₅H₅)₂]₂ (4). Crystals of 4 were orthorhombic with a = 13.6000(8) Å, b = 14.2252(8) Å, c = 17.6500(10) Å in the space group P2(1)2(1)2(1).      

Synthesis and structures of cycloalkylidene-bridged biscyclopentadienyl-tetracarbonyldiiron complexes C(CH2) n [( η 5-C5H4)Fe(CO)]2( μ-CO)2(n = 4, 5 and 6)

A series of cycloalkylidene-bridged biscyclopentadienyldiiron complexes, C(CH₂) _n [(⁵-C₅H₄)Fe(CO)]₂(-CO)₂ (n = 4, 5 and 6) have been synthesized by the reacting C(CH₂) _n Cp₂ (Cp = C₅H₅) with Fe(CO)₅ in refluxing xylene. The molecular structures of C(CH₂)₅[(⁵-C₅H₄)Fe(CO)]₂(-CO)₂ (2) and trans-C(CH₂)₄[(⁵-t-BuC₅H₃)Fe(CO)]₂(-CO)₂ (4t) have been determined by X-ray diffraction. The Fe—Fe bond distance [2.466 Å], in (2) is the shortest reported to date for bridged biscyclopentadienyldiiron complexes.     

Study of allylic rearrangement in (μ-H)Os3(μ-O=CNRCH2CH=CH2)(CO)10 (R=H or CH3) clusters

The migration of the double bond in the allylcarboxamide ligands of (μ-H)Os₃(μ-O=CN RCH₂CH=CH₂) (CO)₁₀ (R=H (1) or CH₃ (2)), (μ-D)Os₃(μ-O=CNDCH₂CH=CH₂) (CO)₁₀, and (μ-H)Os₃(μ-O=CNHCD₂CH=CH₂)(CO)₁₀ clusters was studied by¹H,²H, and¹³C NMR spectroscopy. Neither μ-D nor ND groups in the deuterated complexes are directly involved in prototropic processes of allylic rearrangement. Initially, the deuterium atom of the CD₂ group migrates to the ψ-carbon atom of the allyl fragment to form the −CD=CH-CH₂D propenyl moiety, in which the deuterium and hydrogen atoms are gradually redistributed between the ψ-and β-carbon atoms. The triosmium cluster complexes containing the bridging carboxamide ligands O=CNRR' catalyze the allylic rearrangement ofN-allylacetamide. Based on the data obtained, the probable scheme of the allylic rearrangements in clusters1 and2 was proposed. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2182–2186, November, 1999.     

Detection of σ-alkane complexes of manganese by NMR and IR spectroscopy in solution: (η5-C5H5)Mn(CO)2(ethane) and (η5-C5H5)Mn(CO)2(isopentane)

Irradiation of CpMn(CO)₃ in liquid ethane at 135 K at 355 nm yields a photoproduct that exhibits ν(CO) bands in the IR spectrum shifted to low wavenumber with respect to CpMn(CO)₃ that are indicative of a Mn(i) dicarbonyl. Parallel experiments employing in situ irradiation within an NMR probe (133 K, 355 nm photolysis) reveal the ¹H NMR signals of this product and confirm its formulation as the σ-ethane complex CpMn(CO)₂(η²-C1–H-ethane). The resonance of its coordinated C–H group is observed at δ –5.84 and decays with lifetime of ca. 360 s. Analogous photolysis experiments in isopentane solution with IR detection produce CpMn(CO)₂(η²-C–H-isopentane) with similar IR bands to those of CpMn(CO)₂(η²-C–H-ethane). ¹H NMR spectra of the same species were obtained by irradiation of CpMn(CO)₃ in a 60 : 40 mixture of propane and isopentane; three isomers of CpMn(CO)₂(η²-C–H-isopentane) were detected with coordination of manganese at the two inequivalent methyl positions and at the methylene group, respectively. The lifetimes of these isomers are ca. 380 ± 20 s at 135 K and do not vary significantly from each other. These σ-complexes of manganese are far more reactive than those of related CpRe(CO)₂(alkane) complexes which are stable in solution at 170–180 K. The room temperature lifetimes of CpMn(CO)₂(η²-C–H-ethane) and CpMn(CO)₂(η²-C–H-isopentane), as determined by TRIR spectroscopy, are 2.0 ± 0.1 and 28 ± 1 μs, respectively.     

Interconversion of acetyl- and terminal-carbonyl groups on labeled (η5-indenyl)(CO)2Fe13C(O)CH3

The ¹³C-labeled (95–99%) acetyl complex (η⁵-In)(CO)₃Fe¹³C(O)CH₃ (8) (In = indenyl) has been prepared by acylating In(CO)₂Fe⁻ Na⁺ (1) with CH₃ ¹³C(O)Cl. All of the starting 1 must be consumed in this reaction (at −78°C), or 45% of the product results as In(CO)(¹³CO)FeC(O)CH₃ (9). Once isolated, neither 8 nor mixtures of 8 and 9 further redistribute or lose this label after pressurizing under 800 atm CO, or after heating in heptane, THF, or acetonitrile solution. Treating 8 with even trace amounts of 1 or of Cp(CO)₂Fe⁻ Na⁺ (5) rapidly interconverts the acetyl and terminal carbonyls, thus transforming 8 into mixtures of 8 and 9. A mechanism is proposed that involves a labile metalla-β-diketonate In(CO)Fe(Fp-CO)(CH₃¹³CO)⁻ Na⁺.