Syntheses and X-ray crystal structures of [Co(η-CO3)(NH3)4](NO3)·0.5H2O and [(NH3)3Co(μ-OH)2(μ-CO3)Co(NH3)3][NO3]2·H2O

[Co(η²-CO₃)(NH₃)₄](NO₃)·0.5H₂O and [(NH₃)₃Co(μ-OH)₂(μ-CO₃)Co(NH₃)₃][NO₃]₂·H₂O were prepared by prolonged aerial oxidation of a solution of Co(NO₃)₂·6H₂O and ammonium carbonate in aqueous ammonia. The formation of these side products highlights the richness of the chemistry of these systems and the possibility of by products if methods are not strictly adhered to. The X-ray crystal structures of [Co(η²-CO₃)(NH₃)₄][NO₃]·0.5H₂O and [(NH₃)₃Co(μ-OH)₂(μ-CO₃)Co(NH₃)₃][NO₃]₂·H₂O reveal a monomeric octahedral cobalt center with η²-bound CO₃²⁻ in the former, while the latter consists of a dimeric array where the two cobalt centers are bridged by two OH⁻ and one μ₂-CO₃²⁻ groups with three terminal NH₃ ligands for each Co center. In both complexes extensive hydrogen bonding interactions are evident.     

The evaluation of singlet-triplet separations for [W2(μ-H)(μ-Cl)Cl4(μ-dppm)2] and [W2(μ-H)2 (μ-O2CC6H5)2(P(C6H5)3)2] based on P NMR and crystallographic data

The singlet-triplet separations for the edge-sharing bioctahedral (ESBO) complex W₂(μ-H)(μ-Cl)(Cl₄(μ-dppm)₂ · (THF)₃ (II) has been studied by ³¹P NMR spectroscopy. The structural characterization of [W₂(μ-H)₂(μ-O₂CC₆H₅)₂Cl₂(P(C₆H₅)₃)₂] (I) by single-crystal X-ray crystallography has allowed the comparison of the energy of the HOMOLUMO separation determined using the Fenske-Hall method for a series of ESBO complexes with two hydride bridging atoms, two chloride bridging atoms and the mixed case with a chloride and hydride bridging atom. The complex representing the mixed case, [W₂(μ-H)(μ-Cl)Cl₄(μ-dppm)₂ · (THF)₃] (II), has been synthesized and the value of −2J determined from variable-temperature ³¹P NMR spectroscopy.     

Synthesis and characterisation of the methylene-inserted mixed-chalcogenide compounds Fe2(CO)6(μ-SeCH2Te) and Fe2(CO)6(μ-SCH2Te)

The methylene-bridged, mixed-chalogen compounds Fe₂(CO)₆(μ-SeCH₂Te) (1) and Fe₂(CO)₆(μ-SCH₂Te) (3) have been synthesised from the room temperature reaction of diazomethane with Fe₂(CO)₆(μ-SeTe) and Fe₂(CO)₆(μ-STe), respectively. Compounds 1 and 3 have been characterised by IR, ¹H, ¹³C, ⁷⁷Se and ¹²⁵Te NMR spectroscopy. The structure of 1 has been elucidated by X-ray crystallography. The crystalsare monoclinic,space group P2₁/n, A = 6.695(2), B = 13.993(5), C = 14.007(4)Å, β = 103.03(2)°, V = 1278(7) ų, Z = 4, D_c = 2.599 g cm⁻³ and R = 0.030 (R_w = 0.047).     

Synthesis and structural characterization of (μ-H)2RU3(CO)9(μ3-η-C8H12) and (μ-H)RU3(CO)9(μ3-η-C12H19)

The reaction between Ru₃(CO)₁₂ and a cyclic olefin (cis-cyclooctene or trans-cyclododecene) at 100 °C for several hours gives the title compounds (μ-H)₂RU₃(CO)₉(μ₃-η²-C₈H₁₂) (1), and (μ-H)RU₃(CO)₉(μ₃-η³-C₁₂H₁₉) (2), both of which have been characterized by X-ray diffraction studies, IR and NMR spectral measurements and elemental analysis. The prolonged reaction between Ru₃(CO)₁₂ and cis-cyclooctene gives compound HRu₃(CO)₉(C₈H₁₁) (3). Compound 3 has been characterized with IR and NMR spectral analyses. In 1 the cyclooctene ring is linked via a μ₃-η²-alkyne type of bonding to the face of the Ru₃ cluster. It is formally σ-bonded to two of the three Ru atoms and π-bonded to the third Ru. The two hydrides in 1 are bridging Ru---Ru bonds. In 2 the cyclododecene ring is bonded to the Ru₃ face via the μ₃-η³-CCHC linkage. There are two formal σ-bonds from the allyl part to the hydrido-bridged Ru atoms and the η³-allyl linkage to the third Ru atom.     

Synthese et etude des complexes [C5H4(CH2)3C5H4]Ti(C5H5)2 presentant un pont entre deux ligands cyclopentadienyles

The complex (di-η⁵-C₅H₄CH₂CH₂CH₂C₅H₄)Ti(η¹-C₅H₅)₂ (I) can be obtained unambiguously starting from the corresponding bridged titanocene dichloride. Attempts to synthesize the isomeric compounds (η⁵-C₅H₅)₂ Ti(di-η¹-C₅H₄-CH₂CH₂CH₂C₅H₄) (I′) by the action of a convenient bridged dianion on (C₅H₅)₂ TiCl₂ afford several compounds, one of them is the complex I. The possibility of interconversion of these complexes by a fluctional process is discussed.     

Tetrakisdimethylamidozirconium and its dimethylamido lithium adduct: Structures of [zr(nme2)4]2 and zr(nme2)6li2(thf)2

The molecular structure of [Zr(NMe₂)₄]₂ has been determined by an x-ray study and shown to involve a central Zr₂N₈ moiety involving the fusing of two trigonal bipyramidal units along a common axial-equatorial edge. The terminal Zr---NMe₂ units have trigonal planar coordination about the nitrogen atoms: Zr---N = 2.050(5) and 2.104(5) Å, and Zr---N (bridge) = 2.224(3) and 2.453(4) Å for equatorial and axial bonds, respectively. The Zr---Zr distance is 3.704(1) Å as expected for a non-M---M bonding bridged compound. In tetrahydrofuran solution, Zr(NMe₂)₄ and LiNMe₂ react irreversibly giving Zr(NMe₂)₆ Li₂(THF)₂ which has been isolated and characterized by an X-ray study. The central ZrN₆ octahedral moiety is capped on two opposite faces by Li atoms which are also coordinated to an oxygen atom of a THF molecule. Pertinent distances are: Zr---N = 2.22(7) (av.), N---Li = 2.155(25) (av.) and Li---O = 1.915(10) Å.     

Tetrakis(triphenylphosphine oxide) complexes of the lanthanide nitrates; synthesis, characterisation and crystal structures of [La(Ph3PO)4(NO3)3]·Me2CO and [Lu(Ph3PO)4(NO3)2]NO3

The reaction of Ln(NO₃)₃·6H₂O (Ln=La, Ce, Pr or Nd) with a sixfold excess of Ph₃PO in acetone formed [Ln(Ph₃PO)₄(NO₃)₃]·Me₂CO. The crystal structure of the La complex shows a nine-coordinate metal centre with four phosphine oxides, two bidentate and one monodentate nitrate groups, and PXRD studies show the same structure is present in the other three complexes. In CH₂Cl₂ or Me₂CO solutions, ³¹P NMR studies show that the complexes are essentially completely decomposed into [Ln(Ph₃PO)₃(NO₃)₃] and Ph₃PO. Similar reactions in ethanol gave [Ln(Ph₃PO)₃(NO₃)₃] only. In contrast for Ln=Sm, Eu or Gd, only the [Ln(Ph₃PO)₃(NO₃)₃] are formed from either acetone or ethanol solutions. For the later lanthanides Ln=Tb–Lu, acetone solutions of Ln(NO₃)₃·6H₂O and Ph₃PO gave [Ln(Ph₃PO)₃(NO₃)₃] only, even with a large excess of Ph₃PO, but from cold ethanol [Ln(Ph₃PO)₄(NO₃)₂]NO₃ (Ln=Tb, Ho–Lu) were obtained. The structure of [Lu(Ph₃PO)₄(NO₃)₂]NO₃ shows an eight-coordinate metal centre with four phosphine oxides and two bidentate nitrate groups. In solution in CH₂Cl₂ or Me₂CO the tetrakis-complexes show varying amounts of decomposition into mixtures of [Ln(Ph₃PO)₃(NO₃)₃], [Ln(Ph₃PO)₄(NO₃)₂]NO₃ and Ph₃PO as judged by ³¹P{¹H} NMR spectroscopy. The [Ln(Ph₃PO)₃(NO₃)₃] also partially decompose in solution for Ln=Dy–Lu, forming some tetrakis(phosphine oxide) species.     

Structural characterisation of [Pt(NH3)4]2[W(CN)8][NO3]·2H2O donor–acceptor complex

The bimetallic [Pt(NH₃)₄]₂[W(CN)₈][NO₃]·2H₂O is characterised by single-crystal X-ray diffraction [S.G.P2₁/m(11), a=8.0418(7), b=19.122(2), c=9.0812(6) Å, Z=2]. All platinum centres have the square-plane D_4h geometry with average dimensions Pt(1)–N 2.042(2) and Pt(2)–N 2.037(10) Å. The octacyanotungstate anion has the square-antiprismatic D_4d configuration with average dimensions W(1)–C 2.164(13), C–N 1.140(12), W(1)–N 3.303(5) Å. The structure exhibits two different mutual orientations of Pt versus W units resulting in Pt(2)–W(1), W(1)^* separations of 4.77(2), 4.55(2)^* and Pt(1)–W(1) of 6.331(8) Å. A centrosymmetric structure reveals groups of two distinct columns: the first is formed by intercalated NO₃⁻ between parallel [Pt(1)(NH₃)₄]²⁺ planes and the second consists of [W(CN)₈]³⁻ interlayered by, parallel to square faces of W-antiprisms, [Pt(2)(NH₃)₄]²⁺. The structure is stabilised through a three-dimensional hydrogen bond network via nitrogen atoms of cyanide ligands, hydrogen atoms of NH₃ ligands, water molecules and oxygen atoms of NO₃⁻ counteranions. The vibrational pattern and the range of ν(CN) frequencies attributable to the electronic environment of W(V) and W(IV) are consistent with the ground state Pt(II)↔W(V) charge transfer.     

A convenient synthesis of Fe(CO)2(η-S2CNMe2)2 and Fe(η-S2CNMe2)2 from the monodentate dithiocarbamato derivative, [(η-C5H5)(CO)3W(η-SCSNMe2)] and Fe2(CO)9

A high yield synthesis of the carbonyl dithiocarbamato derivative Fe(CO)₂(η²-S₂CNMe₂)₂ and Fe(η²-S₂CNMe₂)₂ by photolysis with visible light of solutions containing Fe₂(CO)₉ or Fe₃(CO)₁₂ and [(η⁵-C₅H₅)(CO)₃W(η¹-SCSNMe₂)] is reported.     

On the synthesis and structure of monoaryllead and diaryllead acetates RPb(OCOCH3)3 and R2Pb(OCOCH3)2

Anhydrous monoaryllead triacetates ArPb(OAc)₃ (Ar = Ph, p-Tolyl, o-Tolyl, 2,5-Xylyl; OAc = OCOMe) were prepared by arylation of Pb(OAc)₄ with ArSn(C₄H₉-n)₃ in the presence of Hg(OCOCF₃)₂. The procedure was adapted for the synthesis of diaryllead diacetates Ar₂Pb(OAc)₂ (Ar = Ph, p-Tolyl, o-Tolyl, p-ClC₆H₄, o-ClC₆H₄) and afforded products with higher purity than other procedures. The crystal structures of PhPb(OAc)₃, Ph₂Pb(OAc)₂ and (o-Tolyl)₂Pb(OAc)₂ were determined by X-ray diffraction. PhPb(OAc)₃ and (o-Tolyl)₂Pb(OAc)₂ are monomeric. The pentagonal bipyramid around Pb in PhPb(OAc)₃, like the trapezoidal bipyramid around Pb in (o-Tolyl)₂Pb(OAc)₂, is heavily distorted, the OAc groups being unsymmetrically chelating. Lead in Ph₂Pb(OAc)₂ is in a distorted octahedral environment. One OAc group is bridging, linking the molecular units to infinite chains, the other OAc group is symmetrically chelating. IR, ¹H, ¹³C and ²⁰⁷Pb NMR spectroscopic data are reported. The structures of p-TolPb(OAc)₃, o-TolPb(OAc)₃ and 2,5-XylPb(OAc)₃ are inferred to be similar to that of PhPb(OAc)₃, and the structure of (o-ClC₆H₄)₂Pb(OAc)₂ is inferred to be similar to that of (o-Tolyl)₂Pb(OAc)₂.     

Crystal structure of a novel Hg(II) complex, [Hg(tri-2-furylphosphine)2(tri-2-furylphosphinoxide)3] [ClO4]2

The Hg(II) complex [Hg(TFP)₂(OTFP)₃][ClO₄]₂ with TFP=tri-2-furyl-phosphine and OTFP=tri-2-furylphosphinoxide has been prepared and characterised. It crystallises in the hexagonal P6₃/m space group with Z=2, a=13.308(3), c=21.092 (4) Å, V=3235(1) Å³. The structure of the complex cation consists of independent molecules with Hg pentacoordinated in exact trigonal bipyramidal geometry.     

Mechanism of formation of (η-C5H5)2NbH3 from the reaction of (η-C5H5)2NbCl2 with hydridoaluminate reducing agents

The mechanism of the transformation of (η⁵-C₅H₅)₂NbCl₂ to (η⁵-C₅H₅)₂NbH₃ by hydridoaluminate reducing agents has been investigated. Results suggest disproportionation of a niobium(IV) hydrite, leading to the trihydride product and a niobium(III) hydridoaluminate, (η⁵-C₅H₅)₂NbH₂AlR₂, which in turn is converted to the trihydride on hydrolysis. (η⁵-C₅H₅)₂NbH₂AlH₂ has been isolated; deuterium labelling shows that hydrogens exchange between ring and metal-bridging positions in this molecule.     

Rhenium(I) methoxo carbonyl complexes containing tetraphosphine or triphosphine ligands; facile separation and X-ray crystallographic studies of d/l- and meso-[{Re2(μ-OMe)2(CO)6}2(μ,μ′-1,1,4,7,10,10-hexaphenyl-1,4,7,10-tetra-phosphadecane)]

Reaction of the activated mixture of Re₂(CO)_10, Me₃NO and MeOH with a 1:1 mixture of rac (d/l)- and meso-1,1,4,7,10,10-hexaphenyl-1,4,7,10-tetraphosphadecane (hptpd) yields a mixture of (d/l)- and meso-[{Re₂(μ-OMe)₂(CO)₆}₂(μ,μ′-hptpd)] 1. The diastereomers can be easily separated by selective dissolution of d/l-1 in benzene, and give clearly distinguishable ¹H- and ³¹P-NMR spectra. The fluxional behavior of d/l-1 in solution has been studied by variable-temperature ¹H- and ³¹P-{¹H}-NMR spectroscopy. The crystal structures of both d/l- and meso-1 have been determined. Both molecules consist of two {Re₂(μ-OMe)₂(CO)₆} moieties which are bridged by the two P---CH₂---CH₂---P moieties of the hptpd ligand. Whilst the molecules of meso-1 possess crystallographic i-symmetry, those of d/l-1 do not have any crystallographic symmetry. These diastereomers therefore give clearly distinguishable Raman spectra in the solid state. Reaction of tris[2-(diphenylphosphino)ethyl]phosphine (tdppep) with the activated mixture affords the complex [{Re₂(μ-OMe)₂(CO)₆}(μ,η²-tdppep)] 2, and the analogous reaction involving bis[2-diphenylphospinoethyl)phenylphosphine (triphos) gives [{Re₂(μ-OMe)₂(CO)₆}(μ,μ′,η³-triphos){Re₂(CO)₉}] 3 and [{Re₂(μ-OMe)₂(CO)₆}(μ,η²-triphos)] 4.     

Synthesis and crystal structure of the novel trimanganese tetrathiolate incomplete cubane: [Mo(η-C5H5)2(H)CO][Mn3(CO)9(μ-SC6H5)4]

An unexpected trimanganese(I) tetrathiolate-bridged complex, [Mn₃(CO)₉(μ-SC₆H₅)₄]⁻, with an incomplete cubane structure, was obtained by thermal reaction of [Mn₂(CO)₁₀] with [Mo(η⁵-C₅H₅)₂(SC₆H₅)₂]. The structure, established by single-crystal X-ray diffraction studies, shows the cation, [Mo(η⁵-C₅H₅)₂(H)CO]⁺, directed towards the vacant site of the cubane structure. Possible routes by which the anion and the cation could be formed are discussed.     

Synthesis and derivative chemistry of [Ru2(μ-PPh2) (μ-OH) 2(μ-p-cymene) 2]

The cationic diphenylphosphido-bridged compound [Ru₂(μ-PPh₂)(μ-OH)₂(η⁶-p-cymene)₂][PF₆) (2) has been prepared by reaction of the tri-μ-hydroxo complex [Ru₂(μ-OH)₃(η-p-cymene)₂][PF₆] (1) with diphenylphosphine. Complex 2 eliminates water on reaction with protic acids, incorporating the conjugate base of the added acid as a bridging ligand. Formic acid, acetic acid, phenol, and aniline react with 2 to give the monosubstituted compounds [Ru₂(μ-PPh₂)(μ-OH)(μ-L)(η⁶-p-cymene)₂]PF₆] (L = HCO₂, MeCO₂, OPh, or NHPH), whereas methanol, thiophenol, 1,2-benzenedithiol, hydrochloric acid and isopropanol afford the disubstituted derivatives [Ru₂(μ-PPh₂)(μ-L)₂(η⁶-p-cymene)₂]PF₆] (L = OMe, SPh, S₂C₆H₄, Cl, or H).     

The reaction of (μ-H)2Os3(CO)9(PPh3) with ethylene affords the ethylidene complex (μ-H)2Os3(CO)9(PPh3)(μ-CHCH3)

The product isolated from the reaction of (μ-H)₂Os₃(CO)₉(PPh₃) with ethylene is shown to be the ethylidene complex (μ-H)₂Os₃(CO)₉(PPh₃)(μ-CHCH₃) (1) rather than the ethylene complex (μ-H)(H)Os₃(CO)₉(PPh₃)(C₂H₄), as previously claimed. The characterization of 1 is based on a combination of ¹H and ¹³C NMR results. The ¹H NMR data (δ 6.84 (1 H_D), 2.53 (3 H_C), J(CD) = 7.4 Hz) establish the presence of the ethylidene moiety, whereas detailed analysis of the 1-D and 2-D ¹³C NMR spectra of ¹³CO-enriched 1 indicates the relative positions of the ethylidene, hydride, and phosphine ligands on the triosmium framework.     

Template reactions with polynuclear complexes. The reaction of [Mo2(O2CCF3)4(PR3)2] (R = Ph, Et) with 2-aminobenzaldehyde

The binuclear molybdenum(II) complexes [Mo₂(O₂CCF₃)₄(PR₃)₂] (R = Ph, Et) act as templates for the self-condensation of 2-aminobenzaldehyde to give a new class of complexes in which a hydride ion bridges two molybdenum(III) centres, each of which carries a tetradentate macrocyclic ligand (C). The new hydrido complexes [Mo₂(C)₂ (H)(O₂CCF₃)₃(PPh₃)₂] (I), [Mo₂(C)₂(H)₂(O₂CCF₃)₂(PPh₃)₂] (II), and [Mo₂(C)₂ (H)₂(O₂CCF₃)₂(PEt₃)₂]₂ (V) exist in two or more isomeric forms as shown by their IR, ¹H, ³¹P and ¹⁹F NMR spectra. Substitution with thiocyanate, nitrate and tetraphenylborate anions gives the new products [Mo₂(C)₂(H)(CO)(NCS)₃(PPh₃)₂] (III), [Mo₂(C)₂ (H)₂(O₂CCF₃)(NO₃)(PPh₃)₂] (IV), [Mo₂(C)₂(H)(O₂CCF₃)(PPh₃)₂](BPh₄)₂ (VI) and [Mo₂(C)₂(H)₂(O₂CCF₃)(PEt₃)₂](BPh₄) (VII), which also exist in isomeric forms.     

CRYSTAL STRUCTURE OF A HETERONUCLEAR LANTHANIDE COMPLEX OF ERBIUM-YTTRIUM AND GLYCINE[ErY(GlY)_6(H_2O)_4](ClO_4)_65H_2O

The title complex [ErY(Gly)_6(H_2O)_4](ClO_4)_6 5H_2O has been synthesized.Its crystalstructure has been determined by X-ray diffraction method.The crystal is triclinic with space groupP1.The unit cell parameters are as follows:a=11.518(4),b=14.105(7),c=15.530(6) ,α=96.61(3),β=102.74(3),γ=105.70(3)°,V=2327.7(17) ~3,Z=2,Dc=2.091g/cm~3.The structure has been refinedto a final R of 0.0785.The crystal is an infinite chain complex,in which four carboxyl groups fromglycine molecules bridge the Er(Ⅲ)and Y(Ⅲ)ion,other two carboxyl groups bridge two adjacentEr(Ⅲ)or two Y(Ⅲ)ions.     

The coordinatively unsaturated cluster cations [Pt3{M(CO)3}(μ-Ph2PCH2PPh2)3] (M = Re, Mn)

The coordinatively unsaturated cluster [Pt₃(μ₃-CO)(μ-dppm)₃]²⁺ (1, dppm = Ph₂PCH₂PPh₂) reacts with Na⁺[M(CO)₅]⁻ to give the mixed metal clusters [Pt₃{M(CO)₃}(μ-dppm)₃]⁺ (M = Re, 2; Mn, 3). The new clusters are characterized by spectroscopic methods and, for M = Re, by an X-ray structure determination. The Pt₃Re core in 2 is tetrahedral with particularly short metal-metal distances.     

Reactions of fluorinated acid anhydrides, (CF3CO)2O, (CF3SO2)2O and (FSO2)2O, with organometallic substrates of group 15 (As, Sb and Bi)

(C₆H₅)₃MX₂ (M = As, Sb; X = OCOCF₃ and M = Sb, Bi; X = SO₃F, SO₃CF₃) compounds prepared by the interaction of triphenylmetal(V) substrates with (CF₃CO)₂O, (CF₃SO₂)₂O and (FSO₂)₂O have been characterized by molecular weight determination, elemental and spectroscopic (IR, ¹H and ¹⁹F NMR, mass) analyses.