New hydrogen-bonded dimeric and polymeric gold(I) complexes of the heterodifunctional ligand Ph2PNHP(O)Ph2

The preparation of several new gold(I) complexes by chloride metathesis of [AuCl(HL)] [HL=Ph₂PNHP(O)Ph₂] with either HL or K[Ph₂P(E)NP(E)Ph₂] (E=S or Se) is described. All compounds were characterised by a combination of ³¹P{¹H}, ¹H and IR spectroscopy, microanalysis and X-ray crystallography. X-ray structural studies reveal that [Au(HL)₂]Cl [monoclinic, space group P2₁/c, a=9.0726(3) Å, b=21.0847(6) Å, c=12.0131(3) Å, β=105.1090(10)°, V=2219 ų, Z=2, final R=3.97] forms a one dimensional polymeric structure in which alternating [Au(HL)₂]⁺ and Cl⁻ ions are linked through intermolecular N–H⋯Cl hydrogen-bonding. In contrast the three-co-ordinate compound [Au{Ph₂P(Se)NP(Se)Ph₂-Se,Se′}(HL)] [monoclinic, space group P2₁/a, a=21.6752(5) Å, b=9.1200(10) Å, c=24.0742(7) Å, β=106.080(2)°, V=4573 ų, Z=4, final R=8.94] forms hydrogen-bonded dimer pairs analogous to that previously observed in non-complexed HL. The X-ray crystal structure of the gold(I) precursor [AuCl(HL)] has also been determined: monoclinic, space group P2₁/c, a=10.217(8) Å, b=23.256(5) Å, c=20.086(5) Å, β=101.15(4)°, V=4683 ų, Z=8, final R=5.2. The X-ray crystal structure reveals intermolecular N–H⋯OP hydrogen-bonding between adjacent [AuCl(HL)] molecules forming infinite chains.     

Recognition of linear and bent forms of solid μ-oxo-bis[iodotriphenylantimony(V)] (Ph3SbI)2O

Two quite different shapes of the (Ph₃SbI)₂O molecule are found in separate crystals, namely 1a, in which the SbOSb bridge is linear with bond distances of 1.9410–1.9437(6) Å and 1b in which the SbOSb angle is 144.6(4)° and the SbO bonds are longer, averaging 1.971(8) Å. The two species also give distinct vibrational spectra. Both arise from the reaction of triphenylantimony with iodine in moist acetonitrile, 1a as the initial crop of colourless crystals and 1b as organe crystals left when the solution is allowed to evaporate to dryness.     

Diphenylantimony(III) diphenylphosphinate and diphenylmonothiophosphinate: synthesis,spectra and crystal structure

Infrared data suggest that in diphenylantimony(III) diphenylphosphinate and diphenylthiophosphinate, Ph₂Sb[OP(X)Ph₂], where X = O (1 or S (2), the ligands are symmetrically bonded, either as chelating or bridging groups, and the presence of the latter has been confirmed by X-ray diffraction. Ph₂SbO₂PPh₂ (1) is orthorhombic, space group P2₁2₁2₁, with a 9.185(4), b 11.075(4), c 21.099(7) Å and Z 4. Ph₂SbOSPPh₂ (2) is monoclinic, space group P2₁/n with, a 9.842(4), b 10.561(4), c 21.182(7) Å, β 93.19(4)° and Z 4. In both compounds diphenylantimony(III) groups are linked into chains by bridging phosphinate or thiophosphinate groups and antimony achieves pseudotrigonal bipyramidal coordination with the two phenyl groups in equatorial positions. The axial positions are occupied by oxygen and sulphur atoms of the ligands. The independent SbO and PO bond lengths in 1 are very similar (2.23, 2.29 and 1.49, 1.51 Å), while in 2 the PO and PS distances, 1.503 and 2.010 Å respectively, also point to symmetrical coordination. Stereochemical activity of the lone pair is considered.     

The first nickel(II) allogon of a ditertiary phosphine ligand: Preparation,spectral and crystallographic characterization of square-planar bis(diphenylphosphinomethyl)dimethylsilanedinitratonickel(II)

The reaction of nickel(II) nitrate with bis(diphenylphosphinomethyl)dimethylsilane in ethanol solution gives Ni(NO₃)₂ · (Ph₂PCH₂)₂SiMe₂, recrystallized as orange and violet crystals from dichloromethane. Vibrational, electronic spectral and magnetic measurements of the initial product indicate the presence of allogons, the first case involving nitrate anions or a ditertiary phosphine ligand. The structure of the orange crystals 1 was determined by single-crystal X-ray diffraction analysis. The crystals are monoclinic, space group P2₁/c with four molecules in a unit cell of dimensions a = 10.512(2), b = 15.821(5), c = 18.948(8) Å, β = 104.87(4)°. The structure was solved by the heavy-atom method and refined by full-matrix least-squares calculations to R = 0.029 for 2563 observed data. In the monomeric molecule the Ni atoms are square planar, with monodentate nitrate groups [NiO = 1.926(2) and 1.933(2) Å]. The bidentate phosphine ligand has a bite angle of 94.81(3)° and the NiP bond distances are 2.166(1) and 2.170(1) Å. The six-membered NiP₂C₂Si ring adopts a boat conformation.     

Phosphaniminato-Komplexe des Iods. Synthese und Kristallstrukturen von Ph3PNIO2 und Ph3PNSiMe3 · I2

Phosphoraneiminato Complexes of Iodine. Syntheses and Crystal Structures of Ph₃PNIO₂ and Ph₃PNSiMe₃ · I₂ Ph₃PNIO₂ has been prepared as yellow crystals by the reaction of Ph₃PNSiMe₃ with I₂O₅ in boiling acetonitrile, whereas the molecular complex Ph₃PNSiMe₃ · I₂ is formed as brown crystals by the reaction of Ph₃PNSiMe₃ with iodine in acetonitrile solution. Both complexes were characterized by crystal structure determinations. Ph₃PNIO₂: Space group P2₁/n, Z = 4, 2 858 observed unique reflections, R = 0.039. Lattice dimensions at 19°C: a = 972.8(2), b = 1 743.4(3), c = 1 073.7(2) pm, β = 115.46(3)°. The compound forms monomeric molecules with pyramidal geometry at the iodine atom. The bond angle PNI (126.9°) is unusually small; the PN bond length of 159.2 pm corresponds with a double bond. Ph₃PNSiMe₃ · I₂: Space group P1 , Z = 2, 3 560 observed unique reflections, R = 0.033. Lattice dimensions at 19°C: a = 941.2(2), b = 1 041.7(2), c = 1 287.4(3) pm, α = 78.34(1)°, β = 72.00(2)°, γ = 86.08(2)°. The compound forms monomeric molecules, in which the I₂ molecule and the nitrogen atom of the phosphoraneimine molecule realize a linear N? I? I axis with a bond length N? I of 243.2 pm.     

The crystal structure of Mn(NO)3P(C6H5)3: The first x-ray analysis of a mononuclear metal trinitrosyl complex

The structure of Mn(NO)₃PPh₃ has been analyzed by single-crystal X-ray diffraction. It shows a tetrahedral geometry with essentially linear nitrosyl groups, and an eclipsed configuration around the MnP bond. Average distances and angles are: MnN 1.686(7) Å, MnP 2.315(2) Å, NO 1.165(10) Å, PC 1.815(4) Å, MnNO 177.2(7)°, PMnN 103.6(2)°, NMnN 114.7(4)°. Final R factor 7.3% for 2064 non-zero reflections. The structure of the five-coordinate nitrito complex Mn(NO)₂(ONO)(PEt₃)₂ is also mentioned briefly.     

Molecular structure of two dicyclopentadienylmolybdenum derivatives containing a four-membered ring [Mo(η5-C5H5)2(2-NHNC5H4)][PF6] and [Mo(η5C5H5)2(2-ONC5H4)][PF6]

The structure of the new compound [Mo(η⁵-C₅H₅)₂(2-NHNC₅H₄)][PF₆] (1) has been determined. The crystals are orthorhombic, space group Pca2₁ with a 20.807(1), b 8.0030(8), c 10.056(3) Å, V 1674.5 ų, Z = 4. The structure of [Mo(η⁵-C₅H₅)₂(2-ONC₅H₄)][PF₆] (2) has also been determined. The crystals are orthorhombic, space group Pnma with a 12.727(3), b 10.174(2), c 12.918(1) Å, V 1672.8 ų, Z = 4. The structures were solved by Patterson and difference electron density syntheses and refined by least-squares to R of 0.028 for 1287 reflections for 1 and 0.059 for 1178 reflections for 2.Although not isostructural the two cationic complexes have equivalent geometries with the normal bent bismetallocene structure. For 1 the MoN bond lengths are 2.160(8) and 2.142(9) Å, with a NMoN bond angle of 59.8(3)°, whereas for 2 MoO is 2.142(10), MoN is 2.138(11) Å, the NMoO angle is 61.2(4)°. These parameters are discussed and compared with the corresponding data for similar biscyclopentadienyl complexes of molybdenum(IV). Extended Hückel molecular orbital calculations have been carried out to throw light on the nature of the bonding between the metal and the bidentate ligand.     

The crystal structure of triphenyltin isothiocyanate

The crystal structure of Ph₃SnNCS has been determined by single crystal X-ray diffraction. The crystals are monoclinic, P2₁, a = 19.02(3), b = 11.67(2), c = 15.49(2)Å;, β = 95.64(10)°, Z = 8. The molecules are arranged in infinite zig-zag S…SnNCS…Sn&.sbnd; chains similar to those in Me₃SnNCS, but with slightly longer SnN, shorter SnS bonds, and almost planar SnC₃ units. Principal mean bond lengths and angles are: SnN, 2.22(5); NC, 1.17(8); CS, 1.58(7); SSn, 2.92(1); SnC, 2.09(3); CC, 1.38(2)Å; SnNCm 161(4); CSSn, 97(3); SSnN, 175(3) and CSnC, 119.8(1.5)°.     

Synthesis and structure of the heterotrinuclear chromium-palladium clusters (RC5H4CrCl)2-(μ3S)(μ-SCMe3)2Pd(PPh3) with ferromagnetic exchange interactions over the CrSCr system

Reactions of (RC₅H₄)₂Cr₂(SCMe₃)₂S(I, R = H; II, R = Me) with (PPh₃)₂PdCl₂ in benzene at 20°C gives trinuclear complexes (RC₅H₄)₂Cr₂Cl₂(μ₃-S)(μ-SCMe₃)₂Pd(PPh₃)(III, R = H; IV, R = Me). The structure of IV as a monobenzene solvate is established by an X-ray analysis (black-green triclinic crystals space group P$\text{1}$ with a = 11.403(4), b = 14.933(5), c = 14.131(5) Å, α = 99.13(3), β = 112.72(3), γ = 95.65(3)°, V = 2201.6 Å, Z = 2; IV·C₆H₆). The structure was solved by direct methods and refined in an anisotropic approximation to R = 0.046, R_w = 0.058 for 7643 reflections with I ? 2σ(I). In the molecule of IV metal atoms are separated by non-bonding distances (Cr … Cr 4.079(I), Cr … Pd 3.230(I) and 3.380(I) Å) but linked by the bridging tridentate sulphur atom (CrS 2.339(2) and 2.329(2), PdS 2.327(2) Å), and two SCMe₃ groups between Pd and Cr (CrS 2.396(2) and 2.403(2), PdS 2.350(2) and 2.381(2) Å, Cr?Pd 85.14(6) and 89.92(6)°). The Cl atoms are transferred from Pd to Cr atoms (CrCl 2.308(2) Å) and being terminally coordinated are in trans-positions to each other (as well as η-CH₃C₅H₄ rings) with respect to the Cr₂Pd plane. Cr atoms in III and IV exhibit ferromagnetic exchange interactions over the Cr?Cr system (+2J = 28 and 11 cm^?1, respectively).     

Synthetic and structural studies on some 1,3-diselena- and 1,3-dithia-[3]ferrocenophanes of germanium and tin. crystal and molecular structure of 1,3-diselena-2,2- dichlorogermyl-[3]ferrocenophane

A series of [3]ferrocenophanes of general formula Fe(C₅H₄X)₂YCl₂ and the spiro compounds [Fe(C₅H₄X)₂]₂Ge (X = S, Se; Y = Ge, Sn) have been prepared by the reaction of ferrocene 1,1′-dithiol and ferrocene 1,1′-diselenol with tetrahalides of germanium and tin. Spectroscopic properties of the compounds are reported. In solution, the compounds are fluxional by a bridge reversal process. The crystal structure of 1,3-diselena-2,2-dichlorogermyl-[3]ferrocenophane at 163 K. has been determined by X-ray diffraction methods. At that temperature, crystals have space group P2₁/n with a 6.222(3), b 16.156(13), c 12.968(4) Å, β 97.53(1)° and Z = 4. Least-squares refinement gave R = 0.033 for 2834 unique significant reflections whose intensities were measured by counter diffractometry. The two SeGe bond lengths are 2.323 and 2.325(1) Å, with GeCl 2.148 and 2.161(1) Å. The SeGeSe bond angle is 118.2(1)°, ClGeCl 104.7(1)°, and SeGeCl angles range from 106.2 to 109.8(1)°. The SeC bond lengths are 1.901 and 1.904(5) Å, with CSeGe angles of 95.8 and 96.5(2)°. The cyclopentadienyl rings are in an eclipsed conformation with a mean twist angle of 2.7°, and are inclined to one another at 6.1°. The Se atoms are displaced from the ring planes by 0.17 and 0.20 Å yielding a non-bonded intramolecular Se…Se contact of 3.99 Å.     

Synthesis and structure of organosilicon and organogermanium complexes of ytterbium (Ph3E)2Yb(THF)4 with Yb-Si and Yb-Ge bonds

Complexes (Ph₃Si)₂Yb(THF)₄ (1) and (Ph₃Ge)₂Yb(THF)₄ (2) were synthesised by the reactions of Ph₃SiCl or Ph₃GeCl with ytterbium in THF and characterised by X-ray diffraction. Compounds 1 and 2 have similar centrosymmetrical octahedral structures with a central Yb atom bonded to four oxygen atoms of THF molecules in equatorial positions and two Si (or Ge) atoms of SiPh₃ (or GePh₃) fragments in axial positions. In the crystal of 2 there are two symmetrically independent molecules with the same structure. The Yb-Si and Yb-Ge distances in 1 and 2 are 3.158(2) and 3.170(2), 3.141(2) Å, respectively.     

Organometalloidal derivatives of the transition metals: XI. Synthesis and crystal structures of Ph3GeSiMe3 and Ph3GeSiMe2Fe(CO)2(η5-C5H5)

Ph₃GeSiMe₃ and Ph₃GeSiMe₂Fe(CO)₂(η⁵-C₅H₅) have been synthesized and their crystal structures determined. The GeSi bond in iron (2.405(2) Å) is longer by 0.021 Å than in the simple germylsilane (2.384(1) Å). The significant shortening of the SiFe bond (2.328(1) Å) in the iron complex compared to that in the analogous Ph₃SiSiMe₂Fe(CO)₂(η⁵-C₅H₅) (2.346(1) Å) and spectroscopic data indicate an enhanced SiFe interaction.     

The crystal and molecular structure of bis(triphenylsilicon) carbodiimide

The structure of (Ph₃SiN)₂C has been determined by single crystal X-ray diffraction. The structure was solved by direct methods and refined to R = 0.071 for 593 independent diffractometer data. The crystals are rhombohedral, R$\text{3}$ with a = b = c 18.201(20) Å, α = β = γ = 48.82(2)°, and Z = 4. The three crystallographically independent molecules each have linear SiNCNSi chains lying along the crystallographic threefold axes; in two of the molecules the central carbon atom lies on a centre of symmetry. Principal mean bond lengths and angles are: Si, 1.696(25); SiC, 1.846(20); NC, 1.164(30); CC, 1.387(14) Å; CSi, 108.2(6); and CSiC, 110.8(6)°.     

Crystal and molecular structure of 9-methyl-9-phenyl-9,10-dihydro-9-sila-3-azaanthrone

The crystal and molecular structure of 9-methyl-9-phenyl-9,10-dihydro-9-sila-3-azaanthrone has been determined from three-dimensional X-ray diffraction data. The title compound crystals are monoclinic, space group P2₁/b, a = 12.818(2), b = 16.508(2), c = 7.694(1) Å,γ = 105°, 34′(2), Z = 4 and D_cal = 1.278 g cm^?3. The structure was determined by direct methods and refined by full-matrix least-squares calculations in the block-diagonal anisotropic approximation for non-hydrogen atoms to R = 0.043 for 2190 independent reflections, registered at room temperature. This is the first crystal structure determination of a Si-dihydroanthracene derivative with two heterocycles and a planar carbon atom in the C10-position. The tricyclic fragment takes up a planar configuration, the silicon atom having a tetrahedral surrounding, with an endocyclic angle of 103.7(1)° and average bond length SiC, 1.862(1) Å. The CO, 1.220(2) Å, bond length in the carbonylic group exactly corresponds with the double bond length. Average distance NC is 1.335(3) Å, angle CNC, 116.5(2)°.     

Synthesis and structural characterization of acetatobis(triphenylphosphine)dicarbonylmanganese(I), (CH3CO2)Mn(CO)2[P(C6H5)3]2: An organometallic complex containing a chelating acetate ligand

The accidental but intriguing synthesis of acetatobis(triphenylphosphine)dicarbonylmanganese(I), (CH₃CO₂)Mn(CO)₂[P(C₆H₅)₃]₂, has been accomplished by the reaction of NaMn(CO)₅ with (CH₃)₃SiCl followed by the addition of triphenylphosphine and acetic acid. A three-dimensional single-crystal X-ray diffraction analysis has shown an octahedral-like molecule containing a symmetrically oxygen-chelating acetate group, the first such group to be reported in a metal carbonyl complex. The two triphenylphosphine ligands occupy mutually trans positions with the two carbonyl ligands possessing the remaining cis sites in the octahedral complex. The compound crystallizes with four molecules in a monoclinic unit cell of space group symmetry $\text{P}\text{2}{}_1\text{c}$ and of dimensions a = 17.744(2) Å, b = 9.692(1) Å, c = 20.004(2) Å, and β = 106.195(4)°. The relatively long MnO(acetate) bond lengths [2.066(6) and 2.069(7) Å] and the relatively short MnCO bond lengths [1.701(12) and 1.760(13) Å] and the relatively short MnP(C₆H₅)₃ bond lengths [2.260(3) and 2.275(3) Å], compared to the corresponding MnCO and MnP(C₆H₅)₃ bond lengths in other manganese carbonyl triphenylphosphine complexes, are rationalized on the basis that the acetate ligand in this molecule functions primarily as a σ-donor.     

Molecular structure and conformation of gaseous vinyldimethylchlorosilane as determined by electron diffraction

The molecular structure of vinyldimethylchlorosilane has been determined by gas phase electron diffraction at room temperature. The least squares values of the bond lengths (r_g) and bond angles (∠_α) are : r(CH) = 1.086(6) Å, r(CC) = 1.347(5) Å, r(SiC=) = 1.838(6) Å, r(SiC) = 1.876(3) Å, r(SiCl) = 2.078(2) Å, ∠CCSi = 127.8° (1.2) and ∠=CSiCl = 107° (1). Models with pure syn form and a mixture of syn and gauche gave equally good agreement with the diffraction data.     

Synthesis and molecular structure of niobocene trimethylacetate and its π-complex with diphenylacetylene

Niobocene trimethylacetate Cp₂Nb(OOCCMe₃) (I) does not react with usual n-donors (pyridine and triphenylphosphine), but readily adds a π-acceptor molecule of diphenylacetylene (tolane) in benzene to form Cp₂Nb(OOCCMe₃)(π-Ph₂C₂) · 0.5 C₆H₆ (II). The structures of the diamagnetic complexes I and II have been determined by an X-ray diffraction study. These molecules represent wedge-like sandwiches wit dihedral angles between cyclopentadienyl ligands equal to 44.4 and 50.7°, and average NbC distances of 2.39 and 2.44 Å, respectively. The bisector plane of I contains the chelate trimethylacetate group (NbO bond lenghts 2.23 and 2.24 Å) and that of II contains the coordinated tolane molecule and the oxygen atom of the terminal trimethylacetate ligand (NbO 2.16, NbC 2.18 and 2.19, CC 1.29 Å, PhCC angles 141 and 146°). An unusually large splitting of OCO stretching frequencies is observed in the IR spectrum of I (1652?1305 = 347 cm^?1). Structural characteristics of the coordinated CC triple bond in II are similar to those found in Cp(π-Ph₄C₄)Nb(CO)(π-Ph₂C₂) studied earlier. The role played by the Nb^III lone pair in I and II is discussed.     

Cyclometallation reactions in complexes of the type Rh(oq)(CO)(P(o-BrC6F4)Ph2): II. The molecular structure of [Rh(oq)Br(P(o-C6F4)Ph2)(H2O)]2 (oq = 8-oxyquinolinate)

The complex [uRh(oq)Br(P(o-Cu₆F₄)Ph₂)(H₂O)]₂ is obtained by refluxing a solution of Rh(oq)(CO)(P(o-BrC₆F₄)Ph₂) (oq = 8-oxyquinolinate) in toluene. The structure of this compound has been determined by X-ray diffraction and refined to R = 0.061 and R_w = 0.065 factors. The cell has monoclinic symmetry, space group P2₁/n; a 19.513(2), b 17.049(1), c 16.898(1) Å and β 99.69(1)°. The structure consists of two independent Rh(oq)Br(P(o-C₆F₄)Ph₂)H₂O) units linked by hydrogen bonds between the coordinated water molecules and oq ligands to form a distorted boat (six atom ring of junction between the two units). In each unit the metal atom has a distorted octahedral coordination, with a four-atom metallocyclic ring (uRhPCCu) with CRhP and RhPC angles 69.3(2) and 85.3(3)°, respectively, in one unit, and 70.0(2) and 81.1(2)° in the other. The water molecule is readily displaced by a variety of phosphorus donor ligands to form the complexes uRh(oq)Br(P(o-Cu₆F₄)Ph₂)P′, P′ = PPh₃, P(p-CH₃C₆H₄)₃ and P(OCH₃)₃, in which the P atoms are in trans-dispositions.     

New preparation method of chlorotriphenylantimony aryloxides Ph3SbCl(OAr)

The reaction of bis(2,6-dichlorophenoxo)triphenylantimony with triphenylantimony dichloride gave chloro(2,6-dichlorophenoxo)triphenylantimony Ph₃SbCl(OC₆H₃Cl₂-2,6) (I). 2,6-Dichlorophenoxotetraphenylantimony Ph₄Sb(OC₆H₃Cl₂-2,6) (II) was prepared from pentaphenylantimony and bis(2,6- dichlorophenoxo)triphenylantimony. According to X-ray diffraction data, the antimony atoms in I and II have a distorted trigonal-bipyramidal coordination with the following axial: OSbCl, 179.59(5)° (I); CSbO, 178.20(14)° (II); the equatorial angles are 115.72(9)°–124.87(10)° (I) and 111.43(18)°–123.18(19)° (II); the equatorial bond lengths are Sb–C, 2.099(3)–2.111(2) Å (I), 2.111(4)–2.122(5) Å (II); and the axial bond lengths are Sb–Cl, 2.4740(7) Å; Sb–O, 2.0802(16) Å (I); Sb–O, 2.237(3) Å; and Sb–C, 2.167(4) Å (II) (CIF files CCDC no. 998625 for I and no. 1010553 for II).     

Formation and X-ray structure of a silver iodide based polymeric complex (Ag5l6)n(Ph3PCH2l)n

Compounds [(Ph₃P)₂AgS₂CSR (R = Bu^t, TIPT(2,4,6-triisopropylthiophenolato))], formed by inserting CS₂ into the Ag–S bond in AgSR in the presence of PPh₃, react with CH₂I₂ to give pale yellow crystals of (Ag₅I₆)_n(Ph₃PCH₂I)_n, which consist of the polymeric anion (Ag₅I₆)_n⁻ and the cation (Ph₃PCH₂)⁺. The polyanion (Ag₅I₆)_n⁻ is composed of alternate I₅-pentagons and Ag₅-pentagons that are connected by Ag–I bonds along the C axis to form a layered “pagoda” structure, in which there exists an unusual stereochemistry of iodine. Crystal data: monoclinic, space group P2₁/c, a = 15.004(12) Å, b = 27.19(2) Å, c = 7.898 Å, β = 97.18(5)°, V = 3205(4) ų, Z = 4, R = 0.0673 for 2726 observed reflections.