Preparation and Characterization of an Unusual Di-Cobalt Complex; X-Ray Crystal Structure of Co(CO)2(μ-CO)(μ:η2,η4-C4Ph4)Co(CO)2(PPh3)

Reaction of [MoCo(CO)₅(PPh₃)₂(η⁵-C₅H₅)] (1) with diphenylacetylene in tetrahydrofuran at 50 °C yielded two heterobimetallic compounds, [MoCo(CO)₄.(PPh₃){μ-PhC ? CPh}(η⁵-C₅H₅)] (4) and [MoCo(CO)₅{μ-PhC ? CPh} (η⁵-C₅H₅)] (5). However, an unexpected product, Co(CO)₂(μ-CO)(μ:η₂,η⁴-C₄Ph₄)Co(CO)₂(PPh₃) (6), was observed while attempting to grow the crystals for structural determination of 4. The X-ray crystal structure of 6 was determined: triclinic, $ {\rm P}\bar 1 $, a = 11.654(2) Å, b = 12.864(2) Å, c = 13.854(2) Å, α = 89.67(2)°, β = 86.00(2)°, γ= 83.33(2)°, V = 2057.9(6) ų Z=2. In 6, two cobalt fragments are at apical and basal positions of the pseudo-pentagonal pyramidal structure, respectively. The electron count for the apical cobalt fragments is 20, which is rather unusual. It is believed that 6 was formed after the fragmentation and recombination of the fragmented species of 4.     

Phosphido- und arsenido-verbrückte Zweikernkomplexe: Synthese und Struktur von (η5-C5H4R)2Zr{μ-P(SiMe3)2}2M(CO)4 (R = Me,M = Cr; R = H,M = Mo) sowie die Synthese von (η5-C5H5)2Zr{μ-As(SiMe3)2}2Cr(CO)4

Phosphido- and Arsenido-bridged Dinuclear Complexes. Synthesis and Molecular Structure of (η⁵-C₅H₄R)₂Zr{μ-P(SiMe₃)₂}₂M(CO)₄ (R = Me, M = Cr; R = H, M = Mo) and Synthesis of (η⁵-C₅H₅)₂Zr{μ-As(SiMe₃)₂}₂Cr(CO)₄ The reaction of (η⁵-C₅H₄R)₂Zr{E(SiMe₃)₂}₂ with M(CO)₄(NBD) (NBD = norbornadiene) yields the dinuclear phosphido- or arsenido-bridged complexes (η⁵-C₅H₄R)₂Zr{μ-E(SiMe₃)₂}₂M(CO)₄ (R = Me, E = P, M = Cr ( 1 ); R = H, E = P, M = Mo ( 2 ); R = H, E = As, M = Cr ( 3 )). No formation of dinuclear complexes was observed in the reaction of (η⁵-C₅H₄Me)₂Zr{P(SiMe₃)₂}₂ with Ni(PEt₃)₄, Ni(CO)₂(PPh₃)₂ or with NiCl₂(PPh₃)₂ in the presence of Mg. Complexes 1 – 3 were characterised spectroscopically (i. r., n. m. r., m. s.), and X-ray structure investigations were carried out on 1 and 2 . The central four-membered ZrP₂M ring is slightly puckered (dihedral angle between planes ZrP₂/CrP₂ 14.7°, ZrP₂/MoP₂ 14.2°). The Zr? P bond lengths are equivalent ( 1 : Zr? P1 2.654(4), Zr? P2 2.657(4) Å; 2 : Zr? P1 2.6711(9), Zr? P2 2.6585(7) Å), as are the M? P bond lengths (M = Cr ( 1 ): Cr? P1 2.513(4), Cr? P2 2.502(4) Å; M = Mo ( 2 ): Mo? P1 2.6263(7), Mo? P2 2.6311(10) Å). The long Zr ··· M distances of 3.414 Å (M = Cr ( 1 )) and 3.461 Å (M = Mo ( 2 )) indicate the absence of a metal-metal bond.     

Orthomanganated arenes in synthesis VII. Transition-metal mediated formation of a P?P bond; the X-ray crystal structure of Mn2(μ-η1, η1-Ph2PPPh2)(μ-Cl)2(CO)6

The reaction of PPh₂Cl with orthomanganated acetophenone, 2′-CH₃C(O)C₆H₄Mn(CO)₄, gives Mn₂(μ-η₁,η¹-Ph₂PPPh₂)(μ-Cl)₂(CO)₆. An X-ray structure determination [triclinic, space group P1 , a = 10.908(4) Å, b = 11.756(3) Å, c = 12.186(3) Å, α = 96.20(2)°, β = 99.51(2)°, γ = 96.52(2)°] shows two Mn(CO)₃ groups held together by two bridging Cl ligands, and further bridged by a Ph₂P? PPh₂ group prepared in situ.     

Cluster chemistry. 61. Addition of HX (XCl,Br,I) or AuCl(PPh3) to an open Ru5 cluster. X-ray structures of Ru5(μ-H)(μ5-C2PPh2)(μ-PPh2)(μ-Br)(CO)13 and Ru5(μ-H)(μ5-C2PPh2)(μ3-I)(μ-PPh2)(CO)12

Reactions of aqueous HX (X?Cl, Br) or of AuCl(PPh₃) with Ru₅(μ₅-C₂PPh₂)(μ-PPh₂)(CO)₁₃ result in addition of the 4e-donor set (H + X) or (Au(PPh₃) + Cl) with concomitant opening of two Ru? Ru bonds to give complexes containing dimetallated triangular of ‘scorpion’ cores. Aqueous HI reacts similarly, but in this case the iodide ligand spans three Ru atoms, the (H + I) set acting as 6e-donor. The structures of the two title compounds were confirmed by X-ray crystallographic studies. Ru₅(μ-H)(μ₅-C₂PPh₂)(μ-PPh₂)-(μ-Br)(CO)₁₃ is triclinic, space group P1 , a = 9.689(2), b = 11.874(2), c = 20.005(4) Å, α = 84.66(2), β = 82.90(6), λ = 67.51(6)°, Z = 2; 6478 data with I > 2σ(I) were refined to R = 0.0368, R_w = 0.0362. Ru₅(μ-H)(μ₅-C₂PPh₂)(μ₃-I)(μ-PPh₂)-(CO)₁₂.CH₂Cl₂ is monoclinic, space group P2₁/n, a = 14.809(4), b = 20.721(4), c = 17.698(5) Å, β = 111.42(2)°, Z = 4; 7815 data with I > 2σ(I) were refined to R = 0.0440, R_w = 0.0416.     

Crystal and molecular structures of (η-xanthene)- (η-cyclopentadienyl)iron(II) hexafluorophosphate and (η-2-methylthianthrene)(η-cyclopentadienyl)iron(II) hexafluorophosphate

The neutral complexes (η⁵-C₅H₅NiXL (X = Cl, L = PPh₃ (I); L = PCy₃ (II); X = Br, L = PPh₃ (III); L = PCy₃ (IV); X = I, L = PPh₃ (V); L = PCy₃ (VI)) have been obtained by treating NiX₂L₂ with thallium cyclopentadienide. The same reaction in the presence of TlBF₄ gives cationic derivatives [(η⁵-C₅H₅)NiL₂]BF₄ (L = 2PPh₂Me (VII); L = dppe (VIII)), whereas mononuclear complexes containing two different ligands (L₂ = PPh₃ + PCy₃ (IX)) or dinuclear [(η⁵-C₅H₅)Ni(PPh₃)]₂dppe(BF₄)₂ (X) are obtained from the reaction of III with TlBF₄ in the presence of a different ligand. Reduction of cationic complexes with Na/Hg gives very unstable nickel(I) derivatives (η⁵-C₅H₅)NiL₂, which could not be isolated purely. Similar reduction of neutral complexes under CO gives a mixture of decomposition products containing [(η⁵-C₅H₅)Ni(CO)]₂ and nickel(o) carbonyls, whereas in the presence of acetylenes, dinuclear [(η⁵-C₅H₅)Ni]₂(RCCR′) (R = R′ = Ph; R = Ph, R′ = H) are obtained.     

Transition-metal complexes of two valence tautomers of a bulky phenoxide, 2,6-Bu-t2-4-MeC6H2O− (ArO−); preparation and crystal and molecular structure of a phenoxytitanium(III) and a cyclohexadienonylrhodium(I) complex, [Ti(η-C5H5)2 OAr] and [Rh(ArO-η5)(PPh3)2]

The 2,6-di-t-butyl-4-methylphenoxo ligand (ArO^?) is ambidentate, giving rise to the O-bonded 15-electron d¹ [Ti(η-C₅H₅)₂OAr] and the η⁵ -[C(2)-C(6)]-bonded 18-electron d⁸ complex [Rh(ArO-η⁵)(PPh₃)₂], obtained from [{Ti(η-C₅H₅)₂Cl}₂]-LiO Ar and [Rh{N(SiMe₃)₂}(PPh₃)₂]-ArOH, respectively; the average TiC(η) distance is 2.362(10) Å, TiO 1.892(2) Å, and O:C(of Ar) 1.352(3) Å, and TiOC 142.3(2)°; in the Rh^I complex, C(2)C(6) are coplanar (with CC(av.) 1.38(2) Å). C(1)O 1.28 Å, and Rh to C(2) C(6) bond lengthsare in the range 2.19–2.65 Å.     

Darstellung und Struktur von Tetrafluoro(η5-pentamethylcyclopentadienyl)niob und Tetrafluoro(η5-cyclopentadienyl)niob

Preparation and Structure of Tetrafluoro(η⁵-pentamethylcyclopentadienyl) Niobium and Tetrafluoro(η⁵-cyclopentadienyl) Niobium A facile preparation method for (η⁵-C₅Me₅)NbF₄ 3 and (η⁵-C₅H₅)NbF₄ 4 is reported by using AsF₃ as a fluorinating agent. Single crystals obtained from AsF₃ contain the solvent molecule as well as HF. The composition of the crystal is [(η⁵-C₅Me₅)NbF₄(AsF₃)₂]₂ · [(η⁵-C₅Me₅)NbF₄(HF)AsF₃]₂ 5 . The X-ray crystal structure of 5 will be reported. 5 crystallizes triclinic with one furmula in the space group P1 and lattice constants a = 843.1(4), b = 1154.9(6), c = 1910.2(10) pm, α = 91.68(3)°, β = 99.30(3)°, γ = 104.44(2)°.     

Synthesis and characterization of tris(η~5-cyclopentadienyl-μ-carbonyliron)-μ_3-nitrosyl cluster:X-ray structure of[(η~5-C_5H_5)(μ-CO)Fe]_3(μ3-NO).C_4H_8O

Tris)(η 5-cyclopentadienyl-μ-carbonyl-iron)-μ3-nitrosyl cluster was obtained from the reaction of cyclopentadienyl dicarbonyliron dimer with nitrogen monoxide in xylene. The cluster was characterized by elemental analyses, IR, MS and 1H NMR. The crystal structure of [(η5-C5H5)(μ-CO)Fe]3(μ3-NO).C4H8O was determined by X-ray diffraction analysis. It crystallizes in the orthorhombic space group Pnma, a=9.053(2), 6=10.545(2), c=22.525(4) A, V=2150.3(7) A3, Z=4,Dc=1.68 g.cm-3; structure solution and refinement based on 1141 reflections with I > 3.0 (I) (MoKa, A=0.71073 A) converged at R=0.0540. The infrared absorption band at 1325 cm-1 of the μ3-NO in the cluster, which is red shifted, shows that μ3-NO is activated.     

Heterometallische Clusterkomplexe der Typen Re2(μ-PR2)(CO)8(HgY) und ReMo(μ-PR2)(η5-C5H5)(CO)6(HgY) (R = Ph,Cy; Y = Cl,W(η5-C5H5)(CO)3)

Heterometallic Cluster Complexes of the Types Re₂(μ-PR₂)(CO)₈(HgY) and ReMo(μ-PR₂)(η⁵-C₅H₅)(CO)₆(HgY) (R = Ph, Cy; Y = Cl, W(η⁵-C₅H₅)(CO)₃) Dinuclear complexes Re₂(μ-H)(μ-PR₂)(CO)₈ and ReMo(μ-H)(μ-PR₂)(η⁵-C₅H₅)(CO)₆ (R = phenyl, cyclohexyl) were deprotonated and reacted as anions with HgCl₂ to compounds of the both types Re₂(μ-PR₂)(CO)₈HgCl) and ReMo(μ-PR₂)(η⁵-C₅H₅)(CO)₆(HgCl). The heterometallic three-membered cluster complexes correspond to an isolobal exchange of a proton against a cationic HgCl⁺ group. For one of the products ReMo(μ-PCy₂)(η⁵-C₅H₅)(CO)₆(HgCl) has been shown its conversion with NaW(η⁵-C₅H₅)(CO)₃ to ReMo(μ-PCy₂)(η⁵-C₅H₅)(HgW(η⁵-C₅H₅)(CO)₃) under substitution of the chloro ligand, par example. The newly prepared compounds were characterized by means of IR, UV/VIS and ³¹P NMR data. A complete determination of the molecular structure by single crystal analyses was done in the case of Re₂(μ-PCy₂)(CO)₈(HgCl) and of ReMo(μ-PCy₂)(η⁵-C₅H₅)(CO)₆(HgCl) which both are dimer because of the presence of an asymmetric dichloro bridge, and of ReMo(μ-PCy₂)(η⁵-C₅H₅)(CO)₆(HgW(η⁵-C₅H₅)(CO)₃). The structural study illustrates through comparison the influence of various metal types on an interaction between centric and edge-bridged frontier orbitals in three-membered metal rings.     

Synthese,Struktur und Reaktivität von η3‐1,2‐Diphosphaallylkomplexen sowie von [{(η5‐C5H5)(CO)2W–Co(CO)3}{μ‐AsCH(SiMe3)2}(μ‐CO)]

Syntheses, Structure and Reactivity of η³‐1,2‐Diphosphaallyl Complexes and [{(η⁵‐C₅H₅)(CO)₂W–Co(CO)₃}{μ‐AsCH(SiMe₃)₂}(μ‐CO)] Reaction of ClP=C(SiMe₂iPr)₂ ( 3 ) with Na[Mo(CO)₃(η⁵‐C₅H₅)] afforded the phosphavinylidene complex [(η⁵‐C₅H₅)(CO)₂Mo=P=C(SiMe₂iPr)₂] ( 4 ) which in situ was converted into the η¹‐1,2‐diphosphaallyl complex [η⁵‐(C₅H₅)(CO)₂Mo{η³‐tBuPPC(SiMe₂iPr)₂] ( 6 ) by treatment with the phosphaalkene tBuP=C(NMe₂)₂. The chloroarsanyl complexes [(η⁵‐C₅H₅)(CO)₃M–As(Cl)CH(SiMe₃)₂] [where M = Mo ( 9 ); M = W ( 10 )] resulted from the reaction of Na[M(CO)₃(η⁵‐C₅H₅)] (M = Mo, W) with Cl₂AsCH(SiMe₃)₂. The tungsten derivative 10 and Na[Co(CO)₄] underwent reaction to give the dinuclear μ‐arsinidene complex [(η⁵‐C₅H₅)(CO)₂W–Co(CO)₃{μ‐AsCH(SiMe₃)₂}(μ‐CO)] ( 11 ). Treatment of [(η⁵‐C₅H₅)(CO)₂Mo{η³‐tBuPPC(SiMe₃)₂}] ( 1 ) with an equimolar amount of ethereal HBF₄ gave rise to a 85/15 mixture of the saline complexes [(η⁵‐C₅H₅)(CO)₂Mo{η²‐tBu(H)P–P(F)CH(SiMe₃)₂}]BF₄ ( 18 ) and [Cp(CO)₂Mo{F₂PCH(SiMe₃)₂}(tBuPH₂)]BF₄ ( 19 ) by HF‐addition to the PC bond of the η³‐diphosphaallyl ligand and subsequent protonation ( 18 ) and/or scission of the PP bond by the acid ( 19 ). Consistently 19 was the sole product when 1 was allowed to react with an excess of ethereal HBF₄. The products 6 , 9 , 10 , 11 , 18 and 19 were characterized by means of spectroscopy (IR, ¹H‐, ¹³C{¹H}‐, ³¹P{¹H}‐NMR, MS). Moreover, the molecular structures of 6 , 11 and 18 were determined by X‐ray diffraction analysis.     

Synthesis and Crystal Structure of CpFe(CO)l(η1-Ph2PCH2P(O)Ph2)

CpFe(CO)I(η¹-Ph₂PCH₂P(O)Ph₂) 2 was obtained in small yield from reaction of [CpFe(CO)]₂[μ-(Ph₂P)₂CH₂] with diiodine in benzene, or prepared in 82% yield on treating CpFe(CO)I(η¹-Ph₂PCH₂PPh₂) 1 with H₂O₂. Compound 2 crystallizes in the space group P2₁/n, with a = 8.441(2) Å, b = 10.054(2) Å, c = 33.343(8) Å, β = 92.33(2)°, Z = 4, V = 2827(1) ų, R_F = 0.057, and R_w = 0.056.     

Molecular and crystal structure of Bis(η5-cyclopentadienyl)titanium(IV) Dibromide,Ti(η5-C5H5)2Br2

The crystal and molecular structure of Bis(η⁵-cyclopentadienyl)titanium(IV) dibromide, Ti(η⁵?C₅H₅)₂Br₂, has been investigated by an X-ray structure determination. Crystal data: triclinic, a = 7.872(5), b = 11.807(5), c = 12.310(3) Å, α = 107.62(3), β = 100.83(4), γ = 90.69(4)°, V = 1 068(14) ų, T = 293, space group P1 , Z = 4 (there are two crystallographically independent molecules in the asymmetric unit cell and their conformations are similar). Final R and R_w values are 0.068 and 0.073, respectively. The structural results are compared to those for similar type molecules.     

Syntheses,and Crystal Structures of Indium Complexes with η2‐Piperidinyldithiocarbamate and η2‐Pyridine‐2‐Thionate Containing Ligands: Structures of [In(η2‐S2CNC5H10)3] and [In(η2‐pyS)3]

The η²‐thio‐indium complexes [In(η²‐thio)₃] (thio = S₂CNC₅H₁₀, 2 ; SNC₄H₄, (pyridine‐2‐thionate, pyS, 3 ) and [In(η²‐pyS)₂(η²‐acac)], 4 , (acac: acetylacetonate) are prepared by reacting the tris(η²‐acac)indium complex [In(η²‐acac)₃], 1 with HS₂CNC₅H₁₀, pySH, and pySH with ratios of 1:3, 1:3, and 1:2 in dichloromethane at room temperature, respectively. All of these complexes are identified by spectroscopic methods and complexes 2 and 3 are determined by single‐crystal X‐ray diffraction. Crystal data for 2 : space group, C2/c with a = 13.5489(8) Å, b = 12.1821(7) Å, c = 16.0893(10) Å, β = 101.654(1)°, V = 2600.9(3) ų, and Z = 4. The structure was refined to R = 0.033 and Rw = 0.086; Crystal data for 3 : space group, P2₁ with a = 8.8064 (6) Å, b = 11.7047 (8) Å, c = 9.4046 (7) Å, β = 114.78 (1)°, V = 880.13(11) ų, and Z = 2. The structure was refined to R = 0.030 and Rw = 0.061. The geometry around the metal atom of the two complexes is a trigonal prismatic coordination. The piperidinyldithiocarbamate and pyridine‐2‐thionate ligands, respectively, coordinate to the indium metal center through the two sulfur atoms and one sulfur and one nitrogen atoms, respectively. The short C‐N bond length in the range of 1.322(4)–1.381(6) Å in 2 and C‐S bond length in the range of 1.715(2)–1.753(6) Å in 2 and 3 , respectively, indicate considerable partial double bond character.     

Alkynethiolate ligands in the syntheses of iron carbonyl derivatives. Crystal structure of [(η-C5H5)Fe(CO)2(SCCSiMe3)]

The complexes [(η⁵-C₅H₅)Fe(CO)₂(SCCR)] (R=^tBu, SiMe₃) have been obtained by reaction of [(η⁵-C₅H₅)Fe(CO)₂I] and the corresponding LiSCCR. These are the first examples of mononuclear iron compounds containing alkynethiolate ligands. The crystal structure of [(η⁵-C₅H₅)Fe(CO)₂(SCCSiMe₃)] has been determined by X-ray diffraction. The role of [(η⁵-C₅H₅)Fe(CO)₂(SCCSiMe₃)] as a metalloligand in its reactions with metal carbonyls has been explored.     

Preparation of new (η5-C5H4CH3)Mn(NO)(PPh3) and (η7-C7H7)Mo(CO)-(PPh3) complexes

The complex (η⁵-C₅H₄CH₃)Mn(NO)(PPh₃)I has been prepared by the reaction of NaI with [(η⁵-C₅H₄CH₃)Mn(NO)(CO)(PPh₃)]⁺ and also by the reaction of [(η⁵-C₅H₄CH₃)Mn(NO)(CO)₂]⁺ with NaI followed by PPh₃. This iodide compound reacts with NaCN to yield (η⁵-C₅H₄CH₃)Mn(NO)(PPh₃)CN which is ethylated by [(C₂H₅)₃O]BF₄ to yield [(η⁵-C₅H₄CH₃)Mn(NO)(PPh₃)(CNC₂H₅)]⁺. Both [(η⁵-C₅H₄CH₃)Mn(NO)(CO)₂]⁺ and [(η⁵-C₅H₄CH₃)Mn(NO)(PPh₃)(CO)]⁺ react with NaCN to yield [(η⁵-C₅H₄CH₃)Mn(NO)(CN)₂]^?. This anion reacts with Ph₃SnCl to yield cis-(η⁵-C₅H₄CH₃)Mn(NO)(CN)₂SnPh₃ and with [(C₂-H₅)₃O]BF₄ to yield [(η⁵-C₅H₄CH₃)Mn(NO)(CNC₂H₅)₂]⁺. The reaction of (η⁵-C₅-H₄CH₃)Mn(NO)(PPh₃)I with AgBF₄ in acetonitrile yields [(η⁵-C₅H₄CH₃)Mn-(NO)(PPh₃)(NCCH₃)]⁺. The complex (η⁵-C₅H₄CH₃)Mn(NO)(CO)I, produced in the reaction of [(η⁵-C₅H₄CH₃)Mn(NO)(CO)₂]⁺ with NaI, is not stable and decomposes to the dimeric complex (η⁵-C₅H₄CH₃)₂Mn₂(NO)₃I for which a reasonable structure is proposed. Similar dimers can be prepared from the other halide salts. The reaction of (η⁷-C₇H₇)Mo(CO)(PPh₃)I with NaCN yields (η⁷-C₇-H₇)Mo(CO)(PPh₃)CN which is ethylated by [(C₂H₅)₃O]BF₄ to yield [(η⁷-C₇H₇)-Mo(CO)(PPh₃)(CNC₂H₅)]⁺. The interaction of this molybdenum halide complex with AgBF₄ in acetonitrile and pyridine yields [(η⁷-C₇H₇)Mo(CO)(PPh₃)-(NCCH₃)]⁺ and [(η⁷-C₇H₇)Mo(CO)(PPh₃)(NC₅H₅)]⁺, respectively. Both (η⁵-C₅-H₄CH₃)Mn(NO)(PPh₃)I and (η⁷-C₇H₇)Mo(CO)(PPh₃)I are oxidized by NOPF₆ to the respective 17-electron cations in acetonitrile at ?78°C but revert to the neutral halide complex at room temperature. This result is supported by electrochemical data.     

Übergangsmetall-substituierte Acylphosphane und Phosphaalkene. 17 [1] Synthese und Struktur der μ-Isophosphaalkin-Komplexe [(η5-C5H5)2(CO)2Fe2(μ-CO)(μ-CPC6H2R3-2,4,6)] (R = Me,iPr, tBu)

Transition Metal Substituted Acylphosphanes and Phosphaalkenes. 17. Synthesis and Structure of the μ-Isophosphaalkyne Complexes [(η⁵-C₅H₅)₂(CO)₂Fe₂(μ-CO)(μ-C?PC₆H₂R₃)] (R = Me, iPr, tBu) . Condensation of (η⁵-C₅H₅)₂(CO)₂Fe₂(μ-CO)(μ-CSMe)}⁺SO₃CF₃^? ( 6 ) with 2,4,6-R₃C₆H₂PH(SiMe₃) ( 7 ) ( a : R = Me, b : R = iPr, c : R = tBu) affords the complexes (η⁵-C₅H₅)₂(CO)₂Fe₂(μ-CO)(η-C?PC₆H₂R₃-2,4,6) ( 9 a–c ) with edge-bridging isophosphaalkyne ligands as confirmed by the x-ray structure analysis of 9 a .     

Effects on Coordination of Thioether Sites. 4. Structural Analysis of η3-Tripodal Ligand Manganese(I) Complexes

Crystal structures of a series of manganese(I) complexes containing tripodal ligands were determined. For [η³-{CH₃C(CH₂PPh₂)₂(CH₂SPh)-P,P′,S}Mn(CO)₃]PF₆ ( 1 ): a = 10.856(3) Å, b = 19.698(3) Å, c = 17.596(5) Å, β = 96.17(2)°, monoclinic, Z = 4, P2₁/c, R(F_o) = 0.068, R_w(F_o) = 0.055 for 3617 reflections with I_o > 2σ(I_o). For [η³-{CH₃C(CH₂PPh₂)(CH₂SPh)₂-P,P′,S}Mn(CO)₃]PF₆ ( 2 ): a = 9.890(2) Å, b = 20.403(4) Å, c = 10.269(3) Å, β = 117.44(2)°, monoclinic, Z = 2, P2_l, R(F_o) = 0.050, R_w(F_o) = 0.037 for 1760 reflections with I_o > 2σ(I_o). For [η³-{CH₃C(CH₂PPh₂)₂(CH₂S)-P,P′,S}Mn(CO)₃] ( 4 ): a = 8.191(7) Å, b = 10.495(3) Å, c = 19.858(6) Å, α = 99.61(2)°, β = 96.17(2)°, γ = 92.70(4)°, triclinic, Z = 2, P-I, R(F_o) = 0.048, R_w(F_o) = 0.039 for 2973 reflections with I_o > 2σ(I_o). There is no significant difference in the bond lengths of Mn-S bonds among three species in their crystal structures [2.325(2) Å in 1; 2.358(4) in 2; 2.380(2) in 4], but the better donating ability of thiolate in complex 4 appears on the lower frequencies of its carbonyl stretching absorptions.     

Cyclopentadienyl-ruthenium and -osmium chemistry: XXVIII. Reactions and isomerisation of 1,2-bis(methoxycarbonyl)ethenyl complexes: X-ray structures of Ru{Z)-C(CO2Me)CH(CO2Me)} -(CO)(PPh3)(η-C5H5) · 0.5EtOH,Ru{(E)-C(CO2Me)CH(CO2Me)}(dppe)(η-C5H5) and Ru{C(CO2Me)C(CO2Me)C(CO2Me)CH(CO2Me)} - (PPh3)(η-C5H5)

A reinvestigation of the reaction between C₂(CO₂Me)₂ and RuH(PPh₃)₂(η-C₅H₅) and some related complexes is reported. Initial cis addition is followed by conversion into the trans isomer. In the case of the bis-(PPh₃) complex, isomerisation is followed by chelation of the ester CO group with concomitant displacement of one PPh₃ligand. The resulting chelate complex reacts with CO or CNBu^t to give the (Z)-RuC(CO₂Me)CH(CO₂Me) complexes; the (E)-isomer of the carbonyl complex is obtained by addition of C₂(CO₂Me)₂to RuH(CO)(PPh₃)(η-C₅H₅). The ^1Hand ¹³C NMR spectra are not a reliable guide to assignment of the stereochemistry of the vinyl group. Other products isolated from the initial reaction are the bis-insertion product $\text{Ru{C(CO}{}_2\text{Me)C(CO}{}_2\text{Me)C(CO}{}_2\text{Me)}$CH(CO₂Me)} -(PPh₃)(η-C₅H₅) and the 1/2 PPh₃/C₂(CO₂Me)₂ adduct. The molecular structures of Ru{(Z)-C(CO₂Me)CH(CO₂Me)}(CO)(PPh₃(η-C₅H₅) · 0.5EtOH, Ru{(E)-C(C₂Me)CH(CO₂Me)}(dppe)(η-C₅H₅) and $\text{Ru{C(CO}{}_2\text{Me)C(CO}{}_2\text{Me)C(CO}{}_2\text{-Me)}$CH(CO₂Me)}(PPh₃)(η-C₅H₅) have been determined. The cis isomer is monoclinic, space group P2₁,with a 9.328(8), b 17.385(10), c 10.356(7) Å, β 101.78(3)° and Z = 2; 2107 data with I ≥ 2.5σ(I) were refined to R = 0.076 R_w = 0.085. The trans isomer is triclinic, space group P$\text{1}$, with a 10.404(7) b 11.221(6), c 13.230(9) Å, α 92.67(5), β 110.56(5), γ 106.21(5)° and Z = 2; 2520 data with I ≥ 2.5σ(I) were refined to R = 0.055 R_w = 0.068. The butadienyl complex is monoclinic, space group P2₁/a, with a 19.655(8), b 8.674(4), c 21.060(5) Å, β 116.22(3)° and Z = 4; 2724 data with I ≥ 2.5σ(I) were refined to R = 0.042, R_w = 0.047.     

Open metallocenes XI. A pentadienyl compound of heavier rare earth element [2,4-(CH3)2-η5-C5H5]3Tb·1/2THF

The reaction of TbCl₃ with K[2,4-(CH₃)₂ C₅H₅] at 0°C in THF followed by crystallization at ?90°C led to a pale yellow hexagonal prismatic crystalline product [2,4-[CH₃)₂-η⁵-C₅H₅]₃-Tb·1/ 2THF , which is highly sensitive to air and water and rapidly efflorescent at ambient temperature. The single crystal X-ray diffraction data of the compound have been collected at low temperature (-60°C) and the crystal structure has been solved by heavy atom method. It belongs to triclinic system, space group P1 with lattice parameters α=8.477 Å , b=12.583 Å , c=12.858 Å , α=118.08°, β=91.38°, γ=108.75°, V=1120.36 ų and Z=2. Least-squares refinement converged to a final value R=0.043. The compound possesses an idealized C_3h symmetry with three 2,4dimethylpentadienyl ligands bound to the central terbium atom in a pentahapto mode (η⁵). Each unit cell contains two molecules of [2,4-(CH₃)₂-η⁵-C₅H₅]₃Tb and one molecule of solvent THF, of which the role in the lattice has been discussed in detail.     

Crystal and molecular structure of tricyclopentadienyltetrahydrofuranuranium(III), (η5-C5H5)3U·OC4H8

Tricyclopentadienyltetrahydrofuranuranium(III), (η⁵-C₅H₅)₃U·OC₄H₈, crystallizes in the centrosymmetric monoclinic space group P2₁/n with a 8.248(3), b 24.322(17), c 8.357(4) Å, β 101.29(5)°, V 1644.0 ų and ρ(calc) 2.04 g cm^?1 for Z = 4 and mol.wt. 595.0. Diffraction data (Mo-K_α, 2θ(max) 45°) were collected on an Enraf-Nonius CAD4 diffractometer and the structure was refined to R_w(F) 4.7% for those 1530 reflections having I > 2σ(I). The molecule consists of a distorted tetrahedral arrangement of THF and (η⁵-C₅H₅) ligands with CpUCp angles in the range 110.4–122.4° and CpUO angles between 90.2 and 106.0°. Individual uranium-carbon distances range from 2.76(2) to 2.82(2) Å and average 2.79[1] Å. The uranium-oxygen distance of 2.551(10) Å suggests a 10-coordinate U³⁺ radius of 1.20 Å in this class of compounds.