Basische metalle : XXXVI. Die synthese stabiler hydrido(olefin)rhodium-komplexe und von[C5H5Rh(PMe3)(η3-CH3CHC6H5)]PF6

The complexes C₅H₅Rh(PMe₃)C₂H₃R′ (R′  H, Me, Ph) and C₅H₅Rh(PR₃)C₂H₄(PR₃  PMe₂Ph, PPrⁱ₃) are prepared by reaction of[PMe₃(C₂H₃R/t')RhCl]₂ or [PR₃(C₂H₄)RhCl]₂ and TlC₅H₅, respectively. They react with HBF₄ in ether/propionic anhydride to form the BF₄ salts of the hydrido(olefin)rhodium cations [C₅H₅RhH(C₂H₃R′)PR₃]⁺(R  Me; R′  H, Me and R  Prⁱ; R′  H). From C₅H₅Rh(PMe₃)C₂H₃Ph and CF₃COOH/NH₄PF₆ the η³-benzyl complex [C₅H₅Rh(PMe₃)(η³-CH₃CHC₆H₅)]PF₆ is obtained. The reversibility of the protonation reactions is demonstrated by temperature-dependent NMR spectra and by deuteration experiments. The complexes C₅H₅Rh(PMe₃)C₂H₃R′ (R′  H, Ph) and C₅H₅Rh(PMe₂Ph)C₂H₄ react with CH₃I in ether to give the salts [C₅H₅RhCH₃(C₂H₃R′)PR₃]I which in THF or CH₃NO₂ yield the neutral compounds C₅H₅RhCH₃(PR₃)I.     

Protonation of the metal—metal bond in Fe2(μ-A)(μ-A′)(CO)4L2 complexes (A  A′ SC6H5, P(C6H5)2, P(CH3)2; A  SC6H5, A′ z.dbnd; P(C6H5)2; L z.dbnd; P(C6H5)3-n(CH3)n). : III. Experimental study of the influence of the A and A′ bridges on the basicity of the metal—metal bond

In order to check the influence of the bridges on the basicity of the metal—metal bond in Fe₂(μ-A)(μ-A′)(CO)₄L₂ complexes, the compounds with A  A′ SC₆H₅, P(C₆H₅)₂; P(CH₃)₂; A  SC₅H₅, A′ P(C₆H₅)₂ and L  P(CH₃)_3-n (C₆H₅)_n (n  0—3) have been prepared. IR and PMR spectroscopic results are interpreted in structural terms, and show that the Fe₂(SC₆H₅)(P(C₆H₅)₂.)-(CO)₄L₂ complexes are non rigid on the NMR time scale for n = 0, 1. Replacement of the first SC₆H₅ bridge by a P(C₆H₅)₂ bridge markedly increase the basicity of the metal—metal bond, but replacement of the second SC₆H₅ bridge has no significant effect.     

Structural study of iron carbonyl derivatives: IV. Synthesis and crystal and molecular structure of syn-[μ-(SCH3)Fe(CO)2P(CH3)3]2

Dimeric palladium(I) complexes of the type [μ-(η³-C₅H₅)-μ-XPd₂(PR₃)₂](X  Br, R  i-Pr, Ph, Cy; X  Cl, I, R  i-Pr) have been prepared by reduction of the complexes [(ν⁵-C₅H₅)(PR₃)PdX] with a variety of reducing agents (Mg,Na/Hg, LiAlH(t-BuO)₃, LiAlH₄, NaBH₄, n-BuMgBr). PMR and IR data and some properties of the new complexes are reported.     

Funktionell substituierte zinnorganische verbindungen v. st]Phosphono- Und phosphonylmethyl-triorganostannane

The synthesis of phosphono- and phosphonylmethyl-triorganostannanes R₃SnCH₂P(O)(OR′)R′′ (R′′  OR′, C₆H₅) via an Arbuzov reaction of R₃SnCH₂I with P(OR′)₃ or C₆H₅P(OR′)₂ (R′′  CH₃, C₂H₅) is described. The new compounds have been studied with regard to their behaviour towards electrophilic (Br₂, HCl, HgBr₂) and nucleophilic (NaOH, LiAlH₄, LiR) agents. Their reaction with chlorophenylphosphines followed by reduction with LiAlH₄ yields the unsymmetrical methylenebis(phosphines) C₆H₅P(R)CH₂PH₂ (R  H, C₆H₅). The title compounds add to the carbonyl group of aldehydes and the CN bond of phenylisocyanate.     

Reactions and properties of some trimethyleneplatinum(IV) complexes: X. Reaction with iodide and thiocyanate ions

The reaction between the platinacyclobutanes [$\text{PtX}{}_2\text{(CH}{}_2\text{CRR′C}$H₂)L₂] (X  Cl, Br; L  C₅H₅N, 4-CH₃C₅H₄N; R, R′  H, CH₃; R  H, R′  CH₃, C₆H₅) and iodide and thiocyanate ions in methyl cyanide solution has been studied. The C₃ moiety is eliminated as the cyclopropane and the process is first order with respect to the platinacyclobutanes and zero to half order with respect to the salt (MY). With the iodides the rate increases in the order Li < Na < K, Et₄N, and methyl substitution in the cyclobutane ring reduces the rate of reaction with Et₄NI. Added pyridine retards the reaction when L  C₅H₅N (X  Cl; R, R′  H) and added dimethylsulphoxide accelerates it.The mechanism suggested involves dissociation of an L ligand and attack of Y^? ions and of M⁺Y^? ion pairs on the five-coordinate intermediate formed.     

Carbamoyl and alkoxycarbonyl complexes of palladium(II) and platinum(II)

Carbamoyl and alkoxycarbonyl complexes of palladium(II) and platinum(II) of the type M(pnp)(CONHR)Cl (pnp = 2,6-bis(diphenylphosphinomethyl)pyridine; M Pd, R  C₆H₅, p-CH₃C₆H₄, p-CH₃OC₆H₄, C₆H₁₁, t-Bu; M  Pt, R  C₆H₅), Pd(pnp)[CON(Pr)₂]Cl (Pr = propyl), M(pnp)(COOR)Cl (M  Pd, R  C₆H₅, CH₃; M  Pt, R  CH₃), Pd(pnp)(COOCH₃)₂ result from reaction of M(pnp)Cl₂ with carbon monoxide and amines or alkoxides at room temperature and atmospheric pressure.The carbamoyl complexes react with bases to give urethane or diphenylurea depending upon the experimental conditions.     

New molybdenocene dihydrocarbyls

The preparation and characterization of [Mo(η⁵-C₅H₅)₂R₂)] (R  C₂H₅, ⁿC₄H₉,C₆H₅) and [Mo(η⁵-C₅H₅)₂R₂] PF₆ (R  C₂H₅, ⁿC₄H₉) are described. Cyclic voltammograms in CH₃CN and CH₂Cl₂ show that the reversible 1-electron oxidation of [Mo(η⁵-C₅H₅)₂R₂] (R  C₂H₅, ⁿC₄H₉) occurs at higher potentials (ca. −210 mV) than that for [Mo(η⁵-C₅H₅)₂(CH₃)₂] (ca. −270 mV).     

Fulvene—platinum complexes: x-ray crystal structure of [Pt(η2-C5H4CPh2)(PPh3)2]

Bis(cycloocta-1,5-diene)platinum reacts with 2,3,4,5-tetraphenylfulvene to afford the complex [Pt(η²-CH₂C₅Ph₄)(cod)] (cod  C₈H₁₂) in which the metal atom is coordinated to the exo-cyclic double bond of the fulvene. Related compounds [Pt(η²-CH₂C₅Ph₄L₂] (L  PPh₃, PMePh₂, PMe₂Ph, AsPh₃ or CNBu^t have also been prepared and characterised. Reaction of the complexes [Pt(C₂H₄)₂(L)] (L  P(cyclo-C₆H₁₁)₃, PPh₃ or AsPh₃) with 2,3,4,5-tetraphenylfulvene yields the compounds [Pt(C₂H₄)(η²-CH₂C₅PH₄)(L)]. NMR data for the new species are reported and discussed. 6,6-Diphenylfulvene reacts with [Pt(cod)₂] and PPh₃ ($\text{1}\text{2}$ mol ratio) to give the complex [Pt(η²-C₅H₄CPh₂)-(PPh₃)₂] in which the metal atom is bonded to carbon atoms C(2) and C(3) of the fulvene ring. This was established by an X-ray diffraction study. Crystals are monoclinic, space group P2₁/n, with Z  4 in a unit cell of dimensions a  13.761(4), b  21.653(13), c  17.395(6) Å, β,  104.46(2)°. The structure has been solved and refined to R  0.064 (R′  0.064) for 3139 independent diffracted intensifies measured at room temperature. The platinum atom is in a trigonal environment formed by the two ligated phosphorus atoms and the CC bond of the fulvene which is elongated to 1.52(3) Å. The c₅ fulvene ring is planar, and makes an angle of 108° with the coordination plane around the platinum. In this plane the metal atom is slightly asymmetrically bonded with PtC 2.15(2) and 2.24(2) Å, and PtP 2.280(6) and 2.301(6) Å.     

Coordination complexes of acetylenic phosphines and diphosphines : V. Acetylene bridged derivatives of dicobalt octacarbonyl

Reactions of the phosphinoacetylenes RR′PCCR″ (R  R′  Ph, R″  H, CF₃, Ph, Me, t-Bu; R  R′  C₆F₅, R″  Ph, Me; R  Ph, R′  Me, R″  Me) with Co₂(CO)₈ have been studied. Complexes of four types have been characterised: (A)(RR′PC₂R″)CO₂(CO)₆ (R  R′  C₆F₅, R″  Ph, Me; R  R′  Ph, R″  t-Bu), (B) (RR′PC₂R″)₂Co₄(CO)₁₀ (R  R′  Ph, R″  H, CF₃, Ph, Me; R  R′  C₆F₅, R″  Me; R  Ph, R′  Me, R″  Me), (C) (RR′PC₂R″)₂Co₂(CO)₆ (R  R′  Ph, R″  t-Bu), (D) (RR′P(O)C₂R″)Co₂(CO)₆ (R  R′  Ph, R″  t-Bu; R  R′  C₆F₅, R  Ph). The complexes were characterised by microanalysis, IR, NMR and where possible mass spectra. Substitution reactions of the complexes with tertiary phosphites are described. In complexes of type (A) only the alkyne function is utilised whereas the tetranuclear compounds (B) have structures in which both alkyne and phosphorus moieties are coordinated. Compounds of type (C) are simple disubstituted phosphine complexes of Co₂(CO)₈ and those of type (D) are μ-alkyne derivatives of acetylenic phosphine oxides. The mechanism of formation of complexes of type (B) is discussed in the light of IR data.     

Reactions of metal carbonyl derivatives : XIII. Reaction of bis[μ-(tert-butylsulphido)tricarbonyl-iron] with tertiary and ditertiary phosphines and phosphites

The ligands L  P(C₂H₅)₃, P(C₆H₅)₃, P(OCH₃)₃ and P(OC₆H₅)₃ react with [Fe(CO)₃(S-t-C₄H₉)]₂ to give mono-substituted Fe₂(CO)₅L(S-t-C₄H₉)₂ or bis-substituted [Fe(CO)₂L(S-t-C₄H₉)]₂ depending on the reaction conditions. With the exception of [Fe(CO)₂P(C₂H₅)₃(S-t-C₄H₉)]₂, the latter derivatives occur both in solution and in the solid state as a single isomer in which the ligands L are bonded trans to the metal-metal bond. Whereas an asymmetrically bis-substituted product, Fe(CO)₃(S-t-C₄H₉)₂Fe(CO)L' is formed in the reaction of [Fe(CO)₃(S-t-C₄H₉)]₂ with L' &2.dbnd; cis-(C₆H₅)₂PC₂H₂P(C₆H₅)₂, symmetrically bis-substituted derivatives [Fe(CO)₂(S-t-C₄H₉)]₂L', in which the ligand bridges the two iron atoms are produced in the corresponding reactions involving L'  (C₆H₅)₂P(CH_2nP(C₆H₅)₂ (n  1 and 2). The NMR spectrum of [Fe(CO)₂P(OCH₃)₃(S-t-C₄H₉)]₂, as well as those of the complexes [Fe(CO)₂P(OCH₃)₃SR]₂ (R  CH₃ and i-C₃H₇) which have also been synthesised in this study, is interpreted in terms of a virtual coupling effect.     

New η-allyl η-cyclopentadienylcobalt cations

[Co(R-η-C₃H₄)(η-C₅H₅)I] is a good precursor for the preparation of some new cationic complexes as the iodide can easily be replaced; thus addition of PEt₃ to the iodo-complex (R  H) gives [Co(η-C₃H₅)(η-C₅H₅)(PEt₃)]⁺. The reactions of [Co(R-η-C₃H₄)(η-C₅H₅))I] (R  H or 2-Me) with AgBF₄ give solutions containing the coordinatively unsaturated species [Co(R-η-C₃H₄)(η-C₅H₅)⁺. The presence of traces of water leads to the formation of [Co(R-ηC₃H₄)-(η-C₅H₅)(H₂O)]⁺. The addition of monodentate ligands L  PEt₃ PPh₃, AsPh₃, SbPh₃, CNCH₃ and bidentate ligands LL  Ph₂PCH₂CH₂PPh₂(dppe) and o-C₆H₄(AsMe₂)₂(diars), gives, respectively mononuclear [Co(2-Me-ηC₃H₄)-(η-C₅H₅)L]⁺ and binuclear ligand-bridged [(2-Me-ηC₃H₄)(η-C₅H₅)CoLLCo(2-Me-ηC₃H₄)(η-C₅H₅))]²⁺ complexes. Crystals of [Co(2-Me-ηC₃H₄)(η-C₅H₅)-(H₂O)]⁺[BF₄]^- are monoclinic, space group P2₁/c, with a 7.858(3), b 10.262(4), c 15.078(4) Å, β 98.36(1)°. The molecular structure contains the cobalt atom bonded to planar 2-Me-allyl and cyclopentadienyl substituents, which are almost parallel with the H₂O molecule in a staggered conformation with respect to the 2-Me group.     

Alkylidenverbrückte diphosphane und dichlalkogenodiphosphorane als liganden in kationischen cyclopentadienyleisencarbonyl-komplexen

Oxidative cleavage of the FeFe bond in [C₅H₅Fe(CO)₂]₂ in the presence of alkylide-bridged diphosphanes LL (LL = (C₆H₅)₂P(CH₂)_n(P(C₆H₅)₂; n = 1–3), (C₆H₅)₂PCH₂As(C₆H₅)₂ and dichalcogenodiphosphoranes (X)LL(X) ((X)LL(X) = (C₆H₅)₂P(X)(CH₂)_n(X)P(C₆H₅)₂; X  O, S, Se; n = 1–3) yields the complexes [C₅H₅Fe(CO)₂L′]BF₄ (L′ = LL, (X)LL(X); X  S, Se) in high yield. the complexes react with Ni(CO)₄ under photochemical conditions to form [C₅H₅Fe(CO)₂(μ-L′)Ni(CO)₃]BF₄ in quantitative yield, and lose a CO group under irradiation (λ_max > 300 nm) to form the chelate compounds [C₅H₅Fe(CO)L′]BF₄, which are isolable for L′  LL (P,As ligand) and (X)LL(X) (X = S, Se). Some substitution reactions with phosphanes are described.     

Preparation,Chemical and structural studies of a new (η-allyl)dihalocarbonyltungsten(II) compound

The complex (C₂H₅)₄N(ν₃H₅)Cl₂(CO)₂WP(C₆H₅)₃] (I) prepared from the anion W(CO)₅Cl, crystallizes in the triclinic system, P1, a 11.264(5), b 14.697(6), c 10.318(4) Å; α 99.37(3), β 111.87(5), γ 90.21°; V 1559ų; Z  2. The structure was refined to R  0.057 for 4509 independent reflections. The crystal is made up of discrete monomeric ions. In the anion the tungsten atom is at the center of an ocahedron, with two chlorine atoms and two CO groups in the equatorial plane, and the two remaining apices occupied by a (ν-allyl) ligand and a triphenylphosphine group.     

Darstellung und chemie von Me2TlN(SiMe3)2 und Tl[N(SiMe3)2]3

The complexes [Rh(η³-C₃H₄R)(η⁵-C₅R′₅)L]⁺BF₄^- (R  1-Me, R′  H, Me; R  2-Me, R′  H) (L  C₅H₅N, Ph₃P, Ph₃As) have been prepared from Rh(η³-C₃H₄R)(η⁵-C₅R′₅)Cl and AGBF₄ in acetone, followed by reaction with the stoicheiometric quantity of L. The ¹H and ¹³C NMR spectra of the salts are reported and discussed.     

Koordinative komplexe des antibasen—basen-systems urantetrachlorid und tricyclopentadienyluran(IV)-chlorid

Novel coordination compounds of uranium tetrachloride with tricyclopentadienyluranium(IV) chloride of the compositions [(C₅H₅)₃U]₂UCl₆· 2DME, [(C₅H₅)₃U]₂UCl₆ and [(C₅H₅)₃U]UCl₅ have been synthesized by the following reactions in dimethoxyethane: (a) UCl₄ + 2TlC₅H₅, (b) UCl₄ + U(C₅H₅)₄ and (c) UCl₄ + 2(C₅H₅)₃UCl.The solvent-free compounds have been prepared in benzene in a similar manner. The physical and chemical properties of these compounds are reported.     

Nickelocene chemistry : II. New methylidyne trinickel cluster compounds

The new methylidene trinickel cluster complexes, [RCNi₃(η⁵-C₅H₅₃] (R  CMe₃ or SiMe₃) and [Me₃SiCNi₃(η⁵-C₅H₅)2(η⁵-C₅H₄CH₂SiMe₃)] have been isolated in low yield from reactions between nickelocene and the corresponding alkyllithium reagents, RCH₂Li. The compounds [RCNi₃(η⁵-C₅H₅)₃] (R  Ph, CMe₃ or SiMe₃) have also been obtained by treatment of the σ-alkylnickel complexes [(η⁵-C₅H₅)Ni(CH₂R)(PPh₃)] with n-BuLi in the presence of an excess of nickelocene, but under similar conditions [(η⁵-C₅H₅)Ni(CH₂C_1OH₇-2)-(PPh₃)] (where C_1OH₇-2  2-naphthyl) failed to give [2-C_1OH₇CNi₃(η⁵-C₅H₅)₃]. The attempted synthesis of [(η⁵-C₅H₅)Ni(CH₂CCH)(PPh₃)] from [(η⁵-C₅H₅)-NiBr(PPh₃)] and CHCCH₂MgBr gave only [(η⁵-C₅H₅)Ni(CCMe)(PPh₃)] by an unusual rearrangement reaction.     

μ-Oxo-bis(triorganoantimon- und -bismutsulfonate). Kristallstruktur von {(CH3)3SbOH2]2}O3SC6H5)2

μ-Oxo-bis(triorganoantimony- and -bismuthsulfonates) (R₃MO₃Sr′)₂O[M  Sb, R  Ph, benzyl, M  Bi, R  Ph; R′  Me, CH₂CH₂OH, CF₃, Ph, 4-CH₃C₆H₄, 2,4-(NO₂)₂C₆H₃] and (Me₃SbO₃SR′)₂O · nH₂O (n  2, R′  CF₃, Ph, 4-CH₃C₆H₄; n  0, R′  CH₃, CH₂CH₂OH) have been prepared by reaction of (Ph₃SbO)₂ and Me₃Sb(OH)₂, respectively, with appropriate sulfonic acids or with (R₃MX)₂O (R  Ph, benzyl; X  Br) and R′SO₃H in the presence of Ag₂O. The anhydrous compounds (Me₃SbO₃SR′)₂O are obtained by heating the hydrates. Me₃Sb(OH)₂ and 2,4-(NO₂)₂C₆H₃SO₃H react to give the hydroxosulfonate Me₃Sb(OH)O₃SR′. CH₃OH solvolyzes the products. A covalent structure, with pentacoordinated Sb or Bi atoms, unidentate O₃SR′ ligands and μ-oxygen in apical, and R in equatorial positions, is inferred from the vibrational data for all nonhydrated sulfonate compounds. A correlation between ν_as(SbOSb) vibration and SbOSb bond angles in hexaphenyl distiboxans was established, which indicates that the SbOSb bridges are linear in (Ph₃SbO₃SR′)₂O (R′  2,4-(NO₂)₂C₆H₃, 2,4,6-(NO₂)₃C₆H₂) and bent in the other compounds. Data also indicate that there is a linear BiOBi bridge in (Ph₃BiO₃SCH₂CH₂OH)₂O. The hydrated compounds have a distinctly different ionic structure one H₂O being coordinated apically to each of the pentacoordinated Sb atoms in the cation [(Me₂SbOH₂)₂O]²⁺. This proposal is verified by the crystal structure determination of (Me₃SbO₃SPh)₂O · 2H₂O which revealed an ionic structure: [(Me₃SbOH₂)₂O](O₃SPh)₂. The angles μ-OSbO(H₂O) of 171.7(2) and 171.0(2)° and μ-OSbC(CH₃) of 98.3° (mean) reflect the distortion of the trigonal bipyramidal surrounding of the Sb atoms, and the long SbO(H₂O) distance of 244.4(5) pm (mean) the rather weak bonding of the water molecules to Sb. The distances S [144.6(6) pm (mean)] and the angles OSO [112.6(4)° (mean)] in the sulfonate anion are essentially identical. Hydrogen bonds exist between the water ligands and O atoms of the anions.     

Formation of organometallic compounds of carbene and carbine types by the interaction of RLi with neodymium and yttrium chlorides in various media

It has been established that in the interaction of NdCl₃ and YCl₃ with RLi, where R  CH₂C₆H₅, CH₂C(CH₃)₂C₆H₅, CH₂Si(CH₃)₃, unusual organometallic compounds are formed. They are stable in hydrocarbon solutions. The benzyl and neophyl derivatives are carbene type complexes containing one R group at a trivalent metal atom. In all cases the reaction is accompanied by the evolution of RH as the main product and some stilbene and tolan when R  CH₂C₆H₅. The mechanism of this reaction is discussed.     

The formation of dimetallocycles from reactions of alkynes with (η-C5Me5)2Rh2(CO)2; X-ray structure of [(η-C5Me5)2Rh2(η-CO) {μ-η2,η2-C(O)C2-(CF3)2}]

The complexes (η-C₅Me₅)₂Rh₂(μ-CO) {μ-η²,η²-C(O)CRCR} are obtained from reactions between (η-C₅Me₅)₂Rh₂(CO)₂ and the alkynes RCCR (R  CF₃, CO₂Me, or Ph) at 25°C. The molecular geometry of the complex with R  CF₃ has been established by X-ray diffraction; the bridging 'ene-one' unit adopts a μ-η²,η² conformation. Other complexes isolated from these reactions include (η-C₅Me₅)Rh(C₆R₆) (R  CF₃, CO₂Me), (η-C₅Me)₂Rh₂(C₄R₄) (R  CO₂Me) and (η-C₅Me₅)₂Rh₂(CO₂C₂R₂) (R  Ph). The reaction between (η-C₅Me₅)₂Rh₂(CO)₂ and C₆F₅CCC₆F₅ gives (η-C₅Me₅)₂Rh₂(CO)₂(C₆F₅C₂C₆F₅). Mononuclear complexes such as (η-C₅Me₅)Co(C₄R₄CO) are the major products isolated from reactions between (η-C₅Me₅)₂CO₂(CO)₂ and alkynes at 25°C.     

Organolanthanoids : II. Preparation and identification of some organolanthanoid species in solution

The organolanthanoid derivatives R₂M (R  C₆F₅, M  Yb or Eu; R  $\text{o}$-HC₆F₄ or PhCC, M  Yb) have been prepared by reaction of the corresponding diorganomercury compounds with ytterbium or europium metal in tetrahydrofuran at room temperature, and ($\text{o}$-HC₆F₄)₂Yb has been obtained by an analogous reaction at 0°C. The compounds were identified by determination of the amounts of polyfluoroarene or phenylacetylene and lanthanoid ions formed on acidolysis of the filtered reaction mixtures. Reaction of samarium with bis(pentafluorophenyl)mercury and of ytterbium with bis(2,3,4,5-tetrafluorophenyl) mercury at room temperature gives more complex products including RMF₂, MF₂ and RMF derivatives (R  C₆F₅, M  Sm; R  $\text{o}$-HC₆F₄, M  Yb), polyfluoropolyphenyls, and more complex organometallic species. These are considered to be derived from decomposition of initially formed (C₆F₅)₂Sm, (C₆F₅)₃Sm, and ($\text{o}$-HC₆f₄)₂Yb derivatives. The decomposition paths include fluoride elimination to give polyfluorobenzynes, reduction of polyfluoroaryl groups by lanthanoid(II) species, and hydrogen abstraction from tetrahydrofuran.