Darstellung und Kristallstruktur von trans-(Ph4As)2[OsCl2(NCS)(SCN)], Schwingungsspektren und Normalkoordinatenanalyse

Preparation and Crystal Structure of trans-(Ph₄As)₂[OsCl₂(NCS) (SCN) ], Vibrational Spectra and Normal Coordinate Analysis By treatment of trans-[OsCl₂I₄]^2? with (SCN)₂ in dichloromethane a mixture of different linkage isomers is formed, from which trans-[OsCl₂(NCS)(SCN)]^2? has been isolated by ion exchange chromatography on diethylaminoethyl cellulose. The X-Ray structure determination on a single crystal of trans-(Ph₄As)₂[OsCl₂(NCS)(SCN)] (triclinic, space group P 1 , a = 12.505(5), b = 12.056(5), c = 19.833(5) Å, α = 108.047(5)°, β = 91.964(5)°, γ = 117.048(5)°, Z = 2) reveals that two cis-positioned Thiocyanate(N) groups are coordinated with Os? N? C angles of 172.1° and 173.0° and two cis-positioned Thiocyanate(S) groups are coordinated with Os? S? C angles of 106.9° and 108.7°. Using the molecular parameters of the X-Ray determination the low temperature (10 K) IR and Raman spectra of the (n-Bu₄N) salt of the linkage isomer are assigned by a normal coordinate analysis based on a modified valence force field. The valence force constants are f_d(OsN) = 1.63 and f_d(OsS) = 1.30 mdyn/Å. Taking into account the trans influence a good agreement between observed and calculated frequencies is achieved.     

Darstellung,Kristallstruktur und Schwingungsspektren von (n-Bu4N)2[(Mo6I)(NCS)]

Synthesis, Crystal Structure, and Vibrational Spectra of (n-Bu₄N)₂[(Mo₆I)(NCS)] By treatment of [(Mo₆I)I]^2– with (SCN)₂ in dichloromethane at –20 °C the hexaisothiocyanato cluster anion [(Mo₆I)(NCS)]^2– is formed. The X-ray structure determination of (n-Bu₄N)₂[(Mo₆I)(NCS)] · 2 Me₂CO (monoclinic, space group P2₁/c, a = 13.168(5), b = 11.964(5), c = 24.636(5) Å, β = 104.960(5)°, Z = 2) shows, that the thiocyanate groups are coordinated exclusively via N atoms with Mo–N bond lengths of 2.141–2.150 Å, Mo–N–C angles of 166–178° and N–C–S-angles of 174–180°. The vibrational spectra exhibit characteristic innerligand vibrations at 2073–2054 (ν_CN), 846–844 (ν_CS) and 480–462 cm^–1 (δ_NCS).     

Zur Insertion in die Lanthanoid–Kohlenstoffbindung Synthese und Struktur von [CpSm(C6H5CH2NNO)]2 und [K(18-Krone-6)CpYb(NCS)2]∞

On the Insertion into the Lanthanide–Carbon Bond. Synthesis and Structure of [Cp Sm(C₆H₅CH₂NNO)]₂ and [K(18-crown-6)Cp Yb(NCS)₂]_∞ The compound [CpSm(CH₂C₆H₅)(thf)] was investigated, regarding its reactions with small molecules. The main subject was to detect an insertion into the Ln–C bond. With N₂O an insertion reaction is observed, yielding the dimer [CpSm(C₆H₅CH₂NNO)]₂ ( 1 ). The structural data of 1 was collected by a single crystal X-Ray diffraction analysis. (Space group P 1, Z = 1, a = 982.8(2) pm, b = 1052.2(2) pm, c = 1383.8(3) pm, α = 89.29(3)°, β = 73.64(3)°, γ = 66.41(3)°). In the dimer, the two Samarium ions are linked via an (η¹ : η²) bridge by two benzyl diazotato ligands. A nearly planar six-membered central Sm₂N₂O₂-ring is formend. Two pentamethylcyclopentadienyl ligands complete the coordination sphere of each Samarium ion, which are thus surrounded by four ligands each and have a distorted tetrahedral coordination geometry. An insertion of a SCN^– fragment in the Ln–C bond could not be observed. The substitution of the benzyl ligand leads to a polymeric chain structure. The new compound [K(18-crown-6)CpYb(NCS)₂]_∞ 2 contains a tetrahedrally coordinated Yb(III)-ion. (Space group P2₁/n}, Z = 4, a = 1640.6(3) pm, b = 1482.2(3) pm, c = 1674.5(3) pm, β = 102.82(1)°).     

Synthese und Kristallstruktur von [N(Hex)4][Cu2(CN)3]

Synthesis and Crystal Structure of [N(Hex)₄] [Cu₂(CN)₃] [N(Hex)₄][Cu₂(CN)₃] has been prepared by solvothermal reaction of CuCN with Tetra‐n‐hexylammoniumiodide in acetone. The crystal structure is built up by condensed (CuCN)₆ and (CuCN)₇ rings, forming a zeolith type cyanocuprate(I) framework [Cu₂(CN)₃^—]. Space group R3; α = 44.482(6), c = 21.283(4) Å, V = 36471(9) ų; Z = 9.     

Crystal Structures of {[Cd(phen)](C6H8O4)3/3} and {[Cd(phen)](C7H10O4)3/3} · 2H2O with C6H10O4 = Adipic Acid and C7H12O4 = Pimelic Acid

Two coordination polymers {[Cd(phen)](C₆H₈O₄)_3/3} ( 1 ) and {[Cd(phen)](C₇H₁₀O₄)_3/3} · 2H₂O ( 2 ) were structurally characterized by single crystal X‐ray diffraction methods. In 1 (C2/c (no. 15), a = 16.169(2)Å, b = 15.485(2)Å, c = 14.044(2)Å, β = 112.701(8)°, U = 3243.9(7)ų, Z = 8), the Cd atoms are coordinated by two N atoms of one phen ligand and five O atoms of three adipato ligands to form mono‐capped trigonal prisms with d(Cd‐O) = 2.271‐2.583Å and d(Cd‐N) = 2.309, 2.390Å. The [Cd(phen)] moieties are bridged by adipato ligands to generate {[Cd(phen)](C₆H₈O₄)_3/3} chains, which, via interchain π—π stacking interactions, are assembled into layers. Complex 2 (P1¯(no. 2), a = 9.986(1)Å, b = 10.230(3)Å, c = 11.243(1)Å, α = 66.06(1)°, β = 87.20(1)°, γ = 66.71(1)°, U = 955.7(2)ų, Z = 2) consists of {[Cd(phen)](C₇H₁₀O₄)_3/3} chains and hydrogen bonded H₂O molecules. The Cd atoms are pentagonal bipyramidally coordinated by two N atoms of one phen ligand and five O atoms of three pimelato ligands with d(Cd‐O) = 2.213—2.721Å and d(Cd‐N) = 2.329, 2.372Å. Through interchain π—π stacking interactions, the {[Cd(phen)](C₇H₁₀O₄)_3/3} chains resulting from [Cd(phen)] moieties bridged by pimelato ligands are assembled in to layers, between which the hydrogen bonded H₂O molecules are sandwiched.     

Tetramethylcyclotetraarsoxane Bridged Copper(I) Halides with Porous Sheet and Framework Structures [CuX{cyclo-(MeAsO)4}] (X=Cl,Br, I) and [Cu3X3{cyclo-(MeAsO)4}2] (X=Cl,Br)

Open sheet and framework structures [CuX{cyclo-(MeAsO)₄}] (X=Cl, Br, I) 1 – 3 and [Cu₃X₃{cyclo-(MeAsO)₄}₂] (X=Cl, Br) 4 and 5 may be prepared by self-assembly from CuX and methylcycloarsoxane (MeAsO)_n in acetonitrile solution. 1 – 3 exhibit 4⁴ nets in which (CuX)₂ units are connected through μ-1 _KAs¹ : 2 _KAs³ coordinated (MeAsO)₄ ligands into large 28-membered rings. In contrast, adjacent [CuX] chains in 4 and 5 are connected into sheets by μ₄-K⁴ As coordinated (MeAsO)₄ building blocks, with μ-1 _KAs¹ : 2 _KAs³ bridging of these layers by independent (MeAsO)₄ cyclotetramers leading to the generation of a porous framework structure. 1 – 5 were characterised by X-ray structural analysis.     

Darstellung,Kristallstrukturen und Schwingungsspektren von [OsBr(acac)(PPh3)] und [OsBr(acac)(AsPh3)]

Synthesis, Crystal Structures, and Vibrational Spectra of [OsBr(acac)(PPh₃)] and [OsBr(acac)(AsPh₃)] By reaction of tetrabromoacetylacetonatoosmate(IV) with PPh₃ or AsPh₃ in ethanol the complexes [OsBr(acac)(PPh₃)] ( 1 ) and [OsBr(acac)(AsPh₃)] ( 2 ) are formed, which are purified by chromatography on silica gel. X-ray structure determinations of single crystals of ( 1 ) (monoclinic, space group P 2₁/n, a = 13.035(2), b = 18.2640(14), c = 16.636(3) Å, β = 112.776(14)°, Z = 4) and ( 2 ) (monoclinic, space group P 2₁/c, a = 13.23(5), b = 18.35(2), c = 16.65(2) Å, β = 112.9(5)°, Z = 4) result in mean bond distances Os–P = 2.413, Os–As = 2.483, Os–Br = 2.488 and Os–O = 2.037 Å. The vibrational spectra (10 K) exhibit the inner ligand vibrations of the acac, PPh₃ and AsPh₃ groups with nearly constant frequencies and the stretching vibrations of OsP at 499–522, of OsAs at 330–339, of OsBr at 213–214 and of OsO in the range 460–694 cm^–1.     

One‐dimensional Cadmium(II) Coordination Polymers: Syntheses and Crystal Structures of [Cd(H2O)3(C5H6O4)]·2H2O,Cd(H2O)2(C6H8O4), and Cd(H2O)2(C8H12O4)

[Cd(H₂O)₃(C₅H₆O₄)]·2H₂O ( 1 ) and Cd(H₂O)₂(C₆H₈O₄) ( 2 ) were prepared from reactions of fresh CdCO₃ precipitate with aqueous solutions of glutaric acid and adipic acid, respectively, while Cd(H₂O)₂(C₈H₁₂O₄) ( 3 ) crystallized in a filtrate obtained from the hydrothermal reaction of CdCl₂·2.5H₂O, suberic acid and H₂O. Compound 1 consists of hydrogen bonded water molecules and linear {[Cd(H₂O)₃](C₅H₆O₄)_2/2} chains, which result from the pentagonal bipyramidally coordinated Cd atoms bridged by bis‐chelating glutarato ligands. In 2 and 3 , the six‐coordinate Cd atoms are bridged by bis‐chelating adipato and suberato ligands into zigzag chains according to {[Cd(H₂O)₃](C₅H₆O₄)_2/2} and {[Cd(H₂O)₂](C₈H₁₂O₄)_2/2}, respectively. The hydrogen bonds between water and the carboxylate oxygen atoms are responsible for the supramolecular assemblies of the zigzag chains into 3D networks. Crystallographic data: ( 1 ) P1¯ (no. 2), a = 8.012(1), b = 8.160(1), c = 8.939(1) Å, α = 82.29(1)°, β = 76.69(1)°, γ = 81.68(1)°, U = 559.6(1) ų, Z = 2; ( 2 ) C2/c (no. 15), a = 16.495(1), b = 5.578(1), c = 11.073(1) Å, β = 95.48(1)°, U = 1014.2(1) ų, Z = 4; ( 3 ) P2/c (no. 13), a = 9.407(2), b = 5.491(1), c = 11.317(2) Å, β = 95.93(3)°, U = 581.4(2) ų, Z = 2.     

Kristallstruktur und Eigenschaften von Calcium- und Strontiumhexathiodiphosphat(IV), Ca2P2S6 und Sr2P2S6, mit einem Beitrag zu Ca5P8 und Pb2P2S6

Crystal Structure and Properties of Calcium and Strontium Hexathiodiphosphate(IV), Ca₂P₂S₆ and Sr₂P₂S₆, with a Contribution on Ca₅P₈ and Pb₂P₂S₆ Ca₂P₂S₆ and Sr₂P₂S₆ were prepared from metal and a mixture of red phosphorus and sulfur (molar ratio M:P:S = 1:1:3) in 2 corundum crucibles inserted in quartz ampullae under vacuum (20 d 900°C). The compounds were obtained as colourless, crystalline powders containing single crystals. They crystallize in the Sn₂P₂S₆ (high temperature form) type structure (P2₁/c, Z = 2): Ca₂P₂S₆ a = 653.2(2)pm, b = 728.1(2)pm, c = 1110.1(4)pm, β = 124.00(4)°, d = 2.50(2); Sr₂P₂S₆ a = 664.3(2)pm, b = 755.7(3)pm, c = 1139.7(3)pm, β = 124.07(2)°, d = 2.97(2). The anions P₂S have staggered confirmation and are arranged with the motif of a cubic close-packing. Sr²⁺ is coordinated by 8S which form a twofold face-capped trigonal prism and belong to 4P₂S. Structure calculations clearly show that Pb₂P₂S₆ also crystallizes in P2₁/c and not in Pc [1]. Also, Raman- and IR-spectra of Ca₅P₈ were recorded at 20°C. The stretching vibrations of P were assigned in analogy to those of P₂S in alkaline earth hexathiodiphosphates(IV). The range of their frequencies (480 to 340 cm^?1) is essentially smaller and shifted to smaller values compared with P₂S in Ca₂P₂S₆ and Sr₂P₂S₆ (620 to 390 cm^?1). The symmetry of P is not D_3d but C_2h as in the case of P₂S.     

(C2H10N2)[BPO4F2] — Structural Relations between [BPO4F2]2— and [Si2O6]4—

(C₂H₁₀N₂)[BPO₄F₂] — Strukturbeziehungen zwischen [BPO₄F₂]^2— und [Si₂O₆]^4— Colourless crystals of (C₂H₁₀N₂)[BPO₄F₂] were prepared from mixture of ethylendiamine, H₃BO₃, BF₃ · C₂H₅NH₂, H₃PO₄ and HCl under mild hydrothermal conditions (220 °C). The crystal structure was determined by single crystal methods (triclinic, P1¯ (no. 2), a = 451.85(5) pm, b = 710.20(8) pm, c = 1210.2(2) pm, α = 86.08(1)°, β = 88.52(2)°, γ = 71.74(1)°, Z = 2) and contains infinite tetrahedral zweier‐single‐chains {[BPO₄F₂]^2—} which are isoelectronic (48e^—) with the polyanions {[Si₂O₆]^4—} of the pyroxene family.     

Zur Kenntnis komplexer Fluoride mit Cu2+ und Pd2+: MPtF6 (M  Pd,Cu) und RbCuPdF5

On Complex Fluorides with Cu²⁺ and Pd²⁺: MPtF₆ (M ? Pd, Cu) and RbCuPdF₅ For the first time single crystals of PdPtF₆ (green), trigonal-rhomboedric, a = 503.8, c = 1431.6 pm, spcgr. R3 ? C (No. 148), Z = 3, CuPtF₆ (orange), triclinic, a = 495.2, b = 498.5, c = 962.4 pm, α = 89.98, β = 104.23, γ = 120.35°, spcgr. P1 ? C (No. 2), Z = 2 and RbCuPdF₅ (orange brown, in connection with investigations on M^IPd₂F₅ [1]), orthorhombic, a = 626.9, b = 719.9, c = 1076.3 pm, spcgr. Pnma? D (No. 62), Z = 4, four circle diffractometer data, have been obtained.     

Die Kristall- und MolekülStruktur von (S4N3)2SbCI5

The structure of (S₄N₃)₂SbCI₅ has been determined by X-ray methods using least-squares′ refinement. The compound crystallises monoclinic; C–P2₁/c, a = 9.24 Å, b = 17.77 Å, c = 11.29 Å, β = 110.06°, Z = 4. The antimony atom has a fivefold coordination the geometry being derived from a deformed octahedron, the S₄N-rings retained their planar shape.     

Synthese und Strukturuntersuchungen von Iodocupraten(I). XV Iodocuprate(I) mit solvatisierten Kationen: [Li(CH3CN)4][Cu2I3] und [Mg{(CH3)2CO}6][Cu2I4]

Synthesis and Structure Investigations of Iodocuprates(I). XV Iodocuprate(I) with Solvated Cations: [Li(CH₃CN)₄] [Cu₂I₃] and [Mg{(CH₃)₂CO}₆][Cu₂I₄] [Li(CH₃CN)₄][Cu₂I₃] 1 and [Mg((CH₃)₂CO)₆][Cu₂I₄] 2 were prepared by reactions of CuI with LiI in acetonitrile and of CuI with MgI₂ in acetone. 1 crystallizes orthorhombic, Pnma, a = 552.7(2), b = 1258.8(8), c = 2516(1) pm, z = 4. [Li(CH₃CN)₄]⁺ cations are located between rod packings of CuI₄ tetrahedra double chains [(CuI_2/2I_2/4)₂]^? parallel to the axis. Short intermolecular anion/cation contacts were observed. The crystal structure of 2 (monoclinic, P2₁/n, a = 1840(2), b = 1059.2(2), c = 1879(2)pm, β = 112.94(4)°, z = 4) is built up by [Mg((CH₃)₂CO)₆]²⁺ cations forming a simple hexagonal sphere packing. The binuclear anions [Cu₂I₄]^2? occupy holes in the trigonal prismatic channels formed by the cations.     

The crystal structure of tris (ethylenediamine), cobalt(III) hexacyanoferrate(III)dihydrate,Co(C2H8N2)3[Fe(CN)6] · 2H2O

The crystal structure of the title compound has been determined from three dimensional x-ray data obtained by the multiple film method. The space group is P2_l/n and the cell dimensions are: a = 14.90, b = 16.84, c = 8.38 Å; β = 93.5° Z = 4. The structure is formed by discrete Co (en) and Fe(CN) ions, both of which have an octahedral configuration. The Fe(CN) ions are approximately octahedrally surrounded by the Co (en) ions while arrangement of Fe (CN) ions around the Co(en) ions completely differs from an octahedron. The mean Fe? C and Co? C dustances are 1.91 and 2.01 Å, respectively. The water molecules do not play an important role in the structure and all distances between oxygen and other atoms indicate the presence of very weak hydrogen bonds. The salts M (en)₃ Q(CN)₆ · H₂O, where M = Co and Cr and Q = Cr, Mn, Fe and Co, are all isomorphous.     

Schwermetall-π-Komplexe. IX. Die Kettenpolymere [(1,2- (CH3)2C6H4BiCl3)2], [(1,3) (CH3)2C6H4BiCl3)2] und [(1,4- (CH3)2C6H4BiCl3)2]

Heavy Metal π-Complexes. IX. The Chain Polymers [(1,2- (CH₃)₂C₆H₄BiCl₃)₂], [(1,3- (CH₃)₂C₆H₄BiCl₃)₂] and [(1,4- (CH₃)₂C₆H₄BiCl₃)₂] In the crystal structures of the three solid state complexes (C₆H₄(CH₃)₂BiCl₃ (C₆H₄(CH₃)₂ = o-xylene: 1 , m-xylene: 2 , p-xylene: 3 ) quasi-dimeric units of almost undistorted, arene coordinated BiCl₃ fragments can be found that are further associated via additional Bi? Cl contacts to form one-dimensional polymeric chains. Whereas the chains of 2 and 3 are constituted by Bi₂Cl₂ four-membered rings only, further Cl-bridging in 1 leads to additional trigonal-bipyramidal arrangements with Bi atoms exhibiting coordination numbers of 3 + 3 + 1 and 3 + 2 + 1, respectively (prim. + sec. Cl contacts + arene). The arene-metal bonding is characterized by Bi-arene distances in the range from 297 – 306 pm, including ring slippages of 24 –41 pm and 73 pm with the Bi atoms being six and seven coordinated, respectively. The direction of this slipping with respect to the arene's methylation sites cannot be understood in terms of electronic influences but is shown to be caused by steric demands. The values IP₁ of the arenes prove to determine the colours of the complexes.     

Darstellung,Schwingungsspektren und Kristallstrukturen von [(Ph3P)2N]2[(W6Cl)I] · 2 Et2O · 2 CH2Cl2 und [(Ph3P)2N]2[(W6Cl)(NCS)] · 2 CH2Cl2

Synthesis, Crystal Structures, and Vibrational Spectra of [(Ph₃P)₂N]₂[(W₆Cl )I ] · 2 Et₂O · 2 CH₂Cl₂ and [(Ph₃P)₂N]₂[(W₆Cl )(NCS) ] · 2 CH₂Cl₂ By treatment of [(W₆Cl)I]^2– with (SCN)₂ in dichloromethane at –20 °C the hexaisothiocyanato cluster anion [(W₆Cl)(NCS)]^2– is formed. X‐ray structure determinations have been performed on single crystals of [(Ph₃P)₂N]₂[(W₆Cl)I] · 2 CH₂Cl₂ · 2 Et₂O ( 1 ) (triclinic, space group P1, a = 10.324(5), b = 14.908(3), c = 17.734(8) Å, α = 112.78(2)°, β = 99.13(3)°, γ = 92.02(3)°, Z = 1) and [(Ph₃P)₂N]₂[(W₆Cl)(NCS)] · 2 CH₂Cl₂ ( 2 ) (triclinic, space group P1, a = 11.115(2), b = 14.839(2), c = 17.036(3) Å, α = 104.46(1)°, β = 105.75(2)°, γ = 110.59(1)°, Z = 1). The thiocyanate ligands of 2 are bound exclusively via N atoms with W–N bond lengths of 2.091–2.107 Å, W–N–C angles of 173.1–176.9° and N–C–S angles of 178.1–179.3°. The vibrational spectra exhibit characteristic innerligand vibrations at 2067–2045 (ν_CN), 879–867 (ν_CS) and 490–482 (δ_NCS). Based on the molekular parameters of the X‐ray determination of 1 the vibrational spectra of the corresponding (n‐Bu₄N) salt of 1 are assigned by normal coordinate analysis. The valence force constants are f_d(WW) = 1.61, f_d(WI) = 1.23 and f_d(WCl) = 1.10 mdyn/Å.     

Darstellung,Kristallstrukturen und Schwingungsspektren von [OsCl(acac)(EPh3)], E = P,As, Sb

Synthesis, Crystal Structures, and Vibrational Spectra of [OsCl(acac)(EPh₃)], E = P, As, Sb By reaction of tetrachloroacetylacetonatoosmate(IV) with PPh₃, AsPh₃ or SbPh₃ in ethanol the complexes [OsCl(acac)(EPh₃)], E = P, As, Sb are formed, which are purified by chromatography on silica gel. X-ray crystal structure determinations of the isotypic single crystals of [OsCl(acac)(EPh₃)] (monoclinic, space group P 2₁/c, Z = 4; E = P ( 1 ): a = 12.972(2), b = 18.255(2), c = 16.517(2) Å, β = 112.61(2)°; E = As ( 2 ): a = 13.173(5), b = 18.299(5), c = 16.429(5) Å, β = 112.346(5)°; E = Sb ( 3 ): a = 13.573(3), b = 18.520(3), c = 16.440(9) Å, β = 111.78(2)°) result in mean bond distances Os–P = 2.412, Os–As = 2.485, Os–Sb = 2.619, Os–Cl = 2.354 and Os–O = 2.032 Å. The IR spectra (10 K) exhibit the inner ligand vibrations of the acac and EPh₃ groups with nearly constant frequencies and the stretching vibrations of OsP at 500–524, of OsAs at 330–339, of OsSb at 271–278, of OsCl at 317–322 and of Os–O in the range 460–694 cm^–1.     

Cs5[Na{W4N10}]: The first framework nitridotungstate(VI)

Cs₅[Na{W₄N₁₀}] was prepared from a mixture of NaNH₂, CsNH₂ and tungsten powder (molar ration 1 : 10 : 4) at 700°C in autoclaves. After the reaction is finished the nitride is embedded in an alkali metal matrix. Dark red crystals were isolated by washing out the alkali metal with liquid ammonia at room temperature. The structure of Cs₅[Na{W₄N₁₀}] was solved by X-ray single crystal data: I4₁ (No. 80), Z = 4, a = 13.926(3) Å, c = 8.723(3) Å, Z(F) ≥ 3σ(F) = 1535, Z(Variables) = 63, R/R_w = 0.040/0.052. The compound is highly sensitive against moisture giving oxotungstates and ammonia. It contains a framework of tetrahedra [WNN_3/2^1.5?]. Sodium shares four terminal nitrogen ligands. Including sodium a distorted, β-cristobalite type arrangement [Na{W₄N₁₀}^5?] results. It contains caesium in all interstices formed by twelve nitrogen ligands in so-called Friauf polyhedra.     

Reaktion von cyclopentadienyl-substituierten Molybdän(V)-tetrachloriden mit LiPH(2,4,6-BuC6H2) und KPPh2(Dioxan)2. Molekülstrukturen von [Cp0Mo(μ-Cl)2]2 und [CpMo2(μ-Cl)3(μ-PPh2)] (Cp0 = C5Me4Et)

Reaction of Cyclopentadienyl Substituted Molybdenum(V) Tetrachlorides with LiPH(2,4,6-Bu C₆H₂) and KPPh₂(Dioxane)₂. Crystal Structures of [Cp⁰Mo(μ? Cl)₂]₂ and [Cp Mo₂(μ? Cl)₃(μ? PPh₂)] (Cp⁰ = C₅Me₄Et) The reaction of [Cp⁰Mo(CO)₃]₂ (Cp⁰ = C₅Me₄Et) and [Cp′Mo(CO)₃]₂ (Cp′ = C₅H₄Me) with PCl₅ in CH₃CN furnishes the Mo(V) complexes Cp⁰MoCl₄(CH₃CN) 1 and Cp′MoCl₄(CH₃CN) 2 in good yields. While 1 and 2 are reduced by LiPH(2,4,6-BuC₆H₂) to the Mo(III) complexes [Cp⁰Mo(μ? Cl)₂]₂ 3 and [Cp′Mo(μ? Cl)₂]₂ 4 , the reaction of 1 with KPPh₂(dioxane)₂ yields the reduction/substitution product [CpMo₂(μ? Cl)₃(μ? PPh)] 5 in low yield. 1 – 4 were characterized spectroscopically (i.r., mass, 3 and 4 also n.m.r.). An X-ray crystal structure determination was carried out on 3 and 5. 3 crystallizes in the triclinic space group P1 (No. 2) with a = 8.278(4), b = 12.508(7), c = 12.826(7) Å, α = 86.78(5), β = 81.55(2), γ = 75.65(4)°, V = 1 272.4 ų and two formula units in the unit cell (data collection at ? 67°C, 4 255 independent observed reflections, R = 2.9%); 5 crystallizes in the triclinic space group P1 (No. 2) with a = 11.536(8), b = 12.307(9), c = 13.157(9) Å, α = 91.41(6), β = 100.42(5), γ = 112.26(6)°, V = 1 688.7 ų and two formula units in the unit cell (data collection at ? 60°C, 6 147 independent observed reflections, R = 4.9%). The crystal structure of 3 shows the presence of centrosymmetric dimeric molecules with four bridging chloro ligands. In 5, two Mo atoms are bridged by three chloro ligands and one PPh₂ ligand. The Mo? Mo bond length in 3 and 5 (2.600(2), 2.596(2) Å and 2.6388(8) Å) is in agreement with a Mo? Mo bond.     

Bis[N-(trimethylsilyl)iminobenzoyl]phosphanide des Lithiums und Zinks – Synthese sowie NMR-spektroskopische,strukturelle und quantenchemische Untersuchungen

Acyl- and Alkylidenephosphanes. XXXV. Bis[ N -(trimethylsilyl)iminobenzoyl]phosphanides of Lithium and Zinc – Syntheses as well as NMR Spectroscopic, Structural, and Quantumchemical Studies From the reaction of bis(tetrahydrofuran)lithium bis(trimethylsilyl)phosphanide with two equivalents of benzonitrile in 1,2-dimethoxyethane, the yellow dme complex ( 2 a ) of lithium bis[N-(trimethylsilyl)iminobenzoyl]phosphanide ( 2 ) was obtained in 69% yield. However, the intermediate {1-[N-lithium-N-(trimethylsilyl)amido]benzylidene}trimethylsilylphosphane ( 1 ), formed by an analogous 1 : 1 addition in diethyl ether, turned out to be unstable and as a consequence could be characterized by nmr spectroscopic methods only; attempts to isolate the compound failed, but small amounts of the neutral complex 2 b , with the ligands benzonitrile and tetrahydrofuran coordinated to lithium, precipitated. The reaction of compound 2 with zinc(II) chloride in diethyl ether gives the orange-red spiro-complex zinc bis{bis[N-(trimethylsilyl)iminobenzoyl]phosphanide} ( 3 ); this complex is also formed from bis[N-(trimethylsilyl)iminobenzoyl]phosphane ( 4 ), easily amenable by a lithium hydrogen exchange of 2 a with trifluoroacetic acid [18], and zinc bis[bis(trimethylsilyl)amide]. As derived from nmr spectroscopic studies and x-ray structure determinations, compounds 2 a {δ³¹P +63.3 ppm; P2₁/n; Z = 4; R₁ = 0.067}, 2 b {δ³¹P +63.3 ppm; P2₁/c; Z = 4; R₁ = 0.063}, 3 {δ³¹P +58.2 ppm; C2/c; Z = 4; R₁ = 0.037} and 4 {δ³¹P +58.1 ppm [18]} exist as cyclic 3-imino-2λ³σ²-phosphapropenylamides and -propenylamine, respectively, in solution as well as in the solid state. Unlike hydrogen derivative 4 the bis[N-(trimethylsilyl)iminobenzoyl]phosphanide fragments N,N′-coordinating either a lithium or a zinc cation are characterized by almost completely equalized bond lengths; typical mean distances and angles are: PC 180.3 and 178.7; CN 130.5 and 131.8; N–Si 175.3 and 179.3; N–Li 202.3; N–Zn 203.5 pm; CPC 108.8° and 110.5°; PCN 130.9° and 132.9°; CN–Li 113.0°, CN–Zn 117.4°; N–Li–N 104.6°; N–Zn–N 108.8°. Alterations in the shape of the six membered chelate rings, caused by an exchange of the 3-imino-2λ³σ²-phosphapropenylamide or related 2λ³σ²-phospha-1,3-dionate units for the corresponding phosphorus free ligands, are discussed in detail. The results of quantumchemical DFT-B3LYP calculations coincide very well with the experimentally obtained findings.