metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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Penta­carbonyl-2κ5C-chlorido-1κCl-bis­­[1(η5)-cyclo­penta­dien­yl][μ2-oxido(meth­yl)methyl­ene-1:2κ2O:C]tungsten(0)zirconium(IV)

aDepartment of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa, and bDepartment of Chemistry and Biochemistry, University of Johannesburg, PO Box 524, Auckland Park, Johannesburg 2006, South Africa
*Correspondence e-mail: ce@sun.ac.za

(Received 26 August 2008; accepted 2 September 2008; online 6 September 2008)

The title compound, [ZrW(C5H5)2(C2H3O)Cl(CO)5] or [W(CO)5C(CH3)OZr(C5H5)2Cl], consists of two metal centres, with a (tungsten penta­carbon­yl)oxymethyl­carbene group coordinating as a monodentate ligand to the chloridozirconocene. The two halves of the mol­ecule are related by a crystallographic mirror plane. Delocalization through the Zr—O—C=W unit is indicated by a short Zr—O distance and a nearly linear Zr—O—C angle.

Related literature

For related literature regarding catalytic data of the title compound, see: Sinn et al. (1980[Sinn, H., Kaminsky, W., Vollmer, H. J. & Woldt, R. (1980). Angew. Chem. Int. Ed. Engl. 19, 390-392.]); Brüll et al. (2001[Brüll, R., Kgosane, D., Neveling, A., Pasch, H., Raubenheimer, H. G., Sanderson, R. & Wahner, U. M. (2001). Macromol. Symp. 165, 11-18.]); Luruli et al. (2004[Luruli, N., Grumel, V., Brüll, R., Du Toit, A., Pasch, H., Van Reenen, A. J. & Raubenheimer, H. G. (2004). J. Polym. Sci., A1 5121-5133.], 2006[Luruli, N., Heinz, L. C., Grumel, V., Brüll, R., Pasch, H. & Raubenheimer, H. G. (2006). Polymer, 47, 56-66.]). For comparable structures, see: Erker et al. (1989[Erker, G., Dorf, U., Lecht, R., Ashby, M. T., Aulbach, M., Schlund, R., Krüger, C. & Mynott, R. (1989). Organometallics, 8, 2037-2044.]); Wolczanski et al. (1983[Wolczanski, P. T., Threlkel, R. S. & Santarsiero, B. D. (1983). Acta Cryst. C39, 1330-1333.]); Esterhuysen et al. (2008[Esterhuysen, C., Nel, I. B. J. & Cronje, S. (2008). Acta Cryst. E64, m1150.]). For a description of the Cambridge Structural Database, see: Allen (2002[Allen, F. H. (2002). Acta Cryst. B58, 380-388.]).

[Scheme 1]

Experimental

Crystal data
  • [ZrW(C5H5)2(C2H3O)Cl(CO)5]

  • Mr = 623.79

  • Orthorhombic, P n m a

  • a = 22.3794 (8) Å

  • b = 12.3852 (7) Å

  • c = 7.2404 (3) Å

  • V = 2006.85 (16) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 6.41 mm−1

  • T = 273 (2) K

  • 0.34 × 0.31 × 0.29 mm

Data collection
  • Philips PW1100 diffractometer

  • Absorption correction: ψ scan (North et al., 1968[North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351-359.]) Tmin = 0.219, Tmax = 0.258 (expected range = 0.133–0.156)

  • 2070 measured reflections

  • 1851 independent reflections

  • 1521 reflections with I > 2σ(I)

  • Rint = 0.042

  • 3 standard reflections every 50 reflections intensity decay: none

Refinement
  • R[F2 > 2σ(F2)] = 0.032

  • wR(F2) = 0.092

  • S = 1.08

  • 1851 reflections

  • 131 parameters

  • H-atom parameters constrained

  • Δρmax = 1.15 e Å−3

  • Δρmin = −1.14 e Å−3

Table 1
Selected geometric parameters (Å, °)

W1—C4 2.192 (9)
O4—C4 1.270 (10)
Zr1—O4 2.026 (6)
C4—O4—Zr1 177.4 (7)

Data collection: PWPC (Gomm, 1998[Gomm, M. (1998). PWPC. Institut für Angewandte Physik, Erlangen, Germany.]); cell refinement: PWPC; data reduction: Xtal3.4 (Hall et al., 1995[Hall, S. R., King, G. S. D. & Stewart, J. M. (1995). Editors. Xtal3.4 Reference Manual. University of Western Australia: Lamb, Perth.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: X-SEED (Barbour, 2001[Barbour, L. J. (2001). J. Supramol. Chem. 1, 189-191.]; Atwood & Barbour, 2003[Atwood, J. L. & Barbour, L. J. (2003). Cryst. Growth Des. 3, 3-8.]); software used to prepare material for publication: publCIF (Westrip, 2008[Westrip, S. P. (2008). publCIF. In preparation.]).

Supporting information


Comment top

Homogeneous equivalents of the heterogeneous catalysts used in Ziegler–Natta polymerization of alkenes are of interest in efforts to understand the mechanism of polymerization. Cp2TiCl2 (I) has been shown to polymerize ethylene when activated by MAO (Sinn et al., 1980). In our ongoing studies into finding improved catalysts for the oligomerization of α-olefins we have studied zirconocene equivalents to (I) where we replaced one of the Cl ligands with a number of different ligands (Brüll et al., 2001). In particular, the use of a tungsten–carbene moiety as a ligand, (II), has been proven to result in an effective catalyst for the oligomerization of 1-pentene, as well as the copolymerization of ethene and 1-pentene, in the presence of MAO (Luruli et al., 2004; Luruli et al., 2006). Herein we report the crystal structure of the title zirconocene complex, (II).

In the molecular structure the Zr—O distance is shorter than all other zirconocene complexes containing a Zr—O—C(R)M (where M = any transition metal) group reported to date (Cambridge Structural Database, v. 5.29; Allen, 2002), except when R = H [1.971 (4) Å; Wolczanski et al., 1983]. The Zr—O—C angle, on the other hand, is more linear than the previously published structures, with a larger value than that of the benzoxycarbene W(CO)5C(C6H5)OZr(C5H5)2OC6H5 (166.1 (5)°; Erker et al., 1989). This, together with the short [1.27 (1)Å] C(carbene)—O distance, suggests that the bridging group forms an acyl-type structure, W—C(Me)O, with a typical hard–hard bond involving σ and π-donation from the O-atom to the Zr-fragment. This is similar to the hafnocene complex W(CO)5C(C6H5)OHf(C5H5)2Cl (Esterhuysen et al., 2008), where the Hf—O—C angle is also nearly linear [171.4 (3)°].

No intermolecular interactions are observed in the crystal structure, with the molecules packing in columns parallel to the a axis.

Related literature top

For related literature regarding catalytic data of the title compound, see: Sinn et al. (1980); Brüll et al. (2001); Luruli et al. (2004, 2006). For comparable structures, see: Erker et al. (1989); Wolczanski et al. (1983); Esterhuysen et al. (2008). For a description of the Cambridge Structural Database, see: Allen (2002).

Experimental top

To a well stirred suspension of W(CO)6 (8.906 g) in 80 ml diethylether a solution of LiCH3 (17 ml, 1.6M in diethylether) in 50 ml diethylether was added. After solvent removal, dissolution of the residue in 100 ml cold water and filtration, a solution of Et4NCl (8.306 g) in 25 ml cold water was added to the filtrate. Upon filtration 1.015 g of the product {[W(CO)5C(CH3)O][NEt4]} was dissolved in 30 ml dichloromethane and added to a solution of Cp2ZrCl2 (0.585 g) in 70 ml dichloromethane. After stirring for 30 min at -40°C AgBF4 (0.389 g) was added and stirred for 90 min at -40°C. After reaching room temperature the solvent was removed and the residue extracted in 5 portions of 10 ml toluene. The extract was filtered, and the filtrate dried over anhydrous MgSO4. The solution was layered with pentane to yield red crystals suitable for X-ray diffraction analysis.

Refinement top

H atoms were positioned geometrically, with C—H = 0.95–0.98 Å, and constrained to ride on their parent atoms, with Uiso(H) = 1.2–1.5Ueq(C).

Computing details top

Data collection: PWPC (Gomm, 1998); cell refinement: PWPC (Gomm, 1998); data reduction: Xtal3.4 (Hall et al., 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001; Atwood & Barbour, 2003); software used to prepare material for publication: publCIF (Westrip, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (II) showing the atomic labelling scheme and displacement ellipsoids drawn at the 50% probability level.
Pentacarbonyl-2κ5C-chlorido-1κCl-bis[1(η5)-cyclopentadienyl][µ2-oxido(methyl)methylene-1:2κ2O:C]tungsten(IV)zirconium(0) top
Crystal data top
[ZrW(C5H5)2(C2H3O)Cl(CO)5]Dx = 2.065 Mg m3
Mr = 623.79Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, PnmaCell parameters from 25 reflections
a = 22.3794 (8) Åθ = 2–17°
b = 12.3852 (7) ŵ = 6.41 mm1
c = 7.2404 (3) ÅT = 273 K
V = 2006.85 (16) Å3Prism, red
Z = 40.34 × 0.31 × 0.29 mm
F(000) = 1176
Data collection top
Philips PW1100
diffractometer
1521 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.042
Graphite monochromatorθmax = 25.0°, θmin = 2.5°
ω/2θ scansh = 026
Absorption correction: ψ scan
(North et al., 1968)
k = 014
Tmin = 0.219, Tmax = 0.258l = 80
2070 measured reflections3 standard reflections every 50 reflections
1851 independent reflections intensity decay: none
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.032Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.092H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.053P)2 + 1.7971P]
where P = (Fo2 + 2Fc2)/3
1851 reflections(Δ/σ)max = 0.001
131 parametersΔρmax = 1.15 e Å3
0 restraintsΔρmin = 1.14 e Å3
Crystal data top
[ZrW(C5H5)2(C2H3O)Cl(CO)5]V = 2006.85 (16) Å3
Mr = 623.79Z = 4
Orthorhombic, PnmaMo Kα radiation
a = 22.3794 (8) ŵ = 6.41 mm1
b = 12.3852 (7) ÅT = 273 K
c = 7.2404 (3) Å0.34 × 0.31 × 0.29 mm
Data collection top
Philips PW1100
diffractometer
1521 reflections with I > 2σ(I)
Absorption correction: ψ scan
(North et al., 1968)
Rint = 0.042
Tmin = 0.219, Tmax = 0.2583 standard reflections every 50 reflections
2070 measured reflections intensity decay: none
1851 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0320 restraints
wR(F2) = 0.092H-atom parameters constrained
S = 1.08Δρmax = 1.15 e Å3
1851 reflectionsΔρmin = 1.14 e Å3
131 parameters
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
W10.812162 (16)0.25000.32704 (5)0.04133 (16)
Cl10.60410 (18)0.25000.5194 (4)0.0896 (10)
O10.8874 (3)0.0780 (5)0.1035 (9)0.092 (2)
C10.8601 (3)0.1384 (6)0.1848 (10)0.0573 (18)
Zr10.59893 (4)0.25000.18263 (11)0.0388 (2)
O20.9032 (3)0.25000.6604 (11)0.078 (2)
C20.8712 (4)0.25000.5381 (14)0.053 (2)
O30.7386 (3)0.0625 (5)0.5187 (10)0.094 (2)
C30.7643 (3)0.1307 (6)0.4506 (10)0.0529 (17)
O40.6885 (3)0.25000.1422 (10)0.0535 (17)
C40.7442 (4)0.25000.1090 (13)0.045 (2)
C50.7572 (6)0.25000.0914 (16)0.089 (5)
H5A0.80060.25000.11050.134*
H5B0.73990.31460.14820.134*0.50
H5C0.73990.18540.14820.134*0.50
C60.6081 (5)0.0817 (7)0.0048 (16)0.088 (3)
H60.64060.07570.08860.106*
C70.6081 (5)0.0484 (6)0.1785 (16)0.085 (3)
H70.64070.01690.24320.102*
C80.5524 (5)0.0696 (8)0.2486 (16)0.083 (3)
H80.53920.05350.37030.100*
C90.5185 (4)0.1185 (7)0.1117 (15)0.074 (2)
H90.47850.14300.12460.088*
C100.5523 (5)0.1253 (7)0.0444 (13)0.079 (3)
H110.53990.15460.15950.095*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
W10.0383 (2)0.0444 (2)0.0413 (2)0.0000.00042 (16)0.000
Cl10.118 (3)0.107 (2)0.0435 (15)0.0000.0088 (17)0.000
O10.099 (4)0.091 (4)0.087 (4)0.026 (4)0.009 (4)0.027 (4)
C10.059 (4)0.058 (4)0.055 (4)0.010 (4)0.003 (3)0.011 (4)
Zr10.0376 (5)0.0378 (5)0.0408 (5)0.0000.0006 (4)0.000
O20.056 (5)0.109 (7)0.068 (5)0.0000.016 (4)0.000
C20.044 (5)0.069 (6)0.047 (5)0.0000.007 (5)0.000
O30.089 (4)0.083 (4)0.111 (5)0.019 (4)0.009 (4)0.034 (4)
C30.051 (4)0.050 (4)0.057 (4)0.006 (3)0.007 (3)0.014 (3)
O40.039 (4)0.066 (5)0.055 (4)0.0000.002 (3)0.000
C40.037 (5)0.050 (5)0.046 (5)0.0000.000 (4)0.000
C50.061 (7)0.162 (14)0.045 (6)0.0000.000 (6)0.000
C60.096 (7)0.052 (5)0.117 (8)0.019 (5)0.039 (7)0.040 (6)
C70.092 (7)0.033 (4)0.130 (10)0.004 (4)0.036 (7)0.004 (5)
C80.104 (7)0.055 (5)0.091 (6)0.026 (5)0.002 (7)0.015 (5)
C90.051 (4)0.058 (5)0.112 (7)0.013 (4)0.013 (5)0.002 (5)
C100.123 (8)0.050 (5)0.062 (5)0.031 (5)0.027 (6)0.000 (4)
Geometric parameters (Å, º) top
W1—C22.019 (10)Zr1—C82.511 (9)
W1—C1i2.030 (8)O2—C21.139 (11)
W1—C12.030 (7)O3—C31.134 (8)
W1—C3i2.033 (7)O4—C41.270 (10)
W1—C32.033 (7)C4—C51.480 (14)
W1—C42.192 (9)C5—H5A0.9800
Cl1—Zr12.441 (3)C5—H5B0.9800
O1—C11.131 (9)C5—H5C0.9800
Zr1—O42.026 (6)C6—C71.390 (13)
Zr1—C92.482 (8)C6—C101.391 (13)
Zr1—C9i2.482 (8)C6—H60.9500
Zr1—C102.485 (8)C7—C81.373 (13)
Zr1—C10i2.485 (8)C7—H70.9500
Zr1—C62.496 (8)C8—C91.387 (13)
Zr1—C6i2.496 (8)C8—H80.9500
Zr1—C7i2.506 (8)C9—C101.362 (12)
Zr1—C72.506 (8)C9—H90.9500
Zr1—C8i2.511 (9)C10—H110.9500
C2—W1—C1i92.2 (3)Cl1—Zr1—C8i80.2 (3)
C2—W1—C192.2 (3)C9—Zr1—C8i108.8 (3)
C1i—W1—C185.8 (5)C9i—Zr1—C8i32.3 (3)
C2—W1—C3i90.7 (3)C10—Zr1—C8i120.3 (3)
C1i—W1—C3i90.4 (3)C10i—Zr1—C8i53.0 (3)
C1—W1—C3i175.3 (3)C6—Zr1—C8i151.7 (4)
C2—W1—C390.7 (3)C6i—Zr1—C8i52.7 (3)
C1i—W1—C3175.3 (3)C7i—Zr1—C8i31.8 (3)
C1—W1—C390.4 (3)C7—Zr1—C8i157.4 (5)
C3i—W1—C393.2 (4)O4—Zr1—C8116.0 (3)
C2—W1—C4176.9 (4)Cl1—Zr1—C880.2 (3)
C1i—W1—C490.1 (3)C9—Zr1—C832.3 (3)
C1—W1—C490.1 (3)C9i—Zr1—C8108.8 (3)
C3i—W1—C487.2 (3)C10—Zr1—C853.0 (3)
C3—W1—C487.2 (3)C10i—Zr1—C8120.3 (3)
O1—C1—W1178.5 (8)C6—Zr1—C852.7 (3)
O4—Zr1—Cl195.6 (2)C6i—Zr1—C8151.7 (4)
O4—Zr1—C9133.5 (2)C7i—Zr1—C8157.4 (5)
Cl1—Zr1—C9104.0 (3)C7—Zr1—C831.8 (3)
O4—Zr1—C9i133.5 (2)C8i—Zr1—C8125.7 (5)
Cl1—Zr1—C9i104.0 (3)O2—C2—W1178.1 (9)
C9—Zr1—C9i82.1 (4)O3—C3—W1178.4 (7)
O4—Zr1—C10108.7 (3)C4—O4—Zr1177.4 (7)
Cl1—Zr1—C10132.9 (2)O4—C4—C5112.3 (9)
C9—Zr1—C1031.8 (3)O4—C4—W1123.0 (7)
C9i—Zr1—C1088.1 (3)C5—C4—W1124.7 (7)
O4—Zr1—C10i108.7 (3)C4—C5—H5A109.5
Cl1—Zr1—C10i132.9 (2)C4—C5—H5B109.5
C9—Zr1—C10i88.1 (3)H5A—C5—H5B109.5
C9i—Zr1—C10i31.8 (3)C4—C5—H5C109.5
C10—Zr1—C10i76.8 (4)H5A—C5—H5C109.5
O4—Zr1—C680.8 (3)H5B—C5—H5C109.5
Cl1—Zr1—C6122.6 (3)C7—C6—C10108.2 (9)
C9—Zr1—C653.0 (3)C7—C6—Zr174.2 (5)
C9i—Zr1—C6119.7 (4)C10—C6—Zr173.4 (5)
C10—Zr1—C632.4 (3)C7—C6—H6125.9
C10i—Zr1—C6101.2 (4)C10—C6—H6125.9
O4—Zr1—C6i80.8 (3)Zr1—C6—H6118.4
Cl1—Zr1—C6i122.6 (3)C8—C7—C6107.2 (9)
C9—Zr1—C6i119.7 (4)C8—C7—Zr174.3 (5)
C9i—Zr1—C6i53.0 (3)C6—C7—Zr173.5 (5)
C10—Zr1—C6i101.2 (4)C8—C7—H7126.4
C10i—Zr1—C6i32.4 (3)C6—C7—H7126.4
C6—Zr1—C6i113.3 (6)Zr1—C7—H7117.8
O4—Zr1—C7i85.2 (3)C7—C8—C9108.4 (10)
Cl1—Zr1—C7i90.5 (3)C7—C8—Zr173.9 (5)
C9—Zr1—C7i135.4 (3)C9—C8—Zr172.7 (5)
C9i—Zr1—C7i53.4 (3)C7—C8—H8125.8
C10—Zr1—C7i130.2 (3)C9—C8—H8125.8
C10i—Zr1—C7i53.7 (3)Zr1—C8—H8119.4
C6—Zr1—C7i145.0 (5)C10—C9—C8108.4 (9)
C6i—Zr1—C7i32.3 (3)C10—C9—Zr174.2 (5)
O4—Zr1—C785.2 (3)C8—C9—Zr175.0 (5)
Cl1—Zr1—C790.5 (3)C10—C9—H9125.8
C9—Zr1—C753.4 (3)C8—C9—H9125.8
C9i—Zr1—C7135.4 (3)Zr1—C9—H9116.9
C10—Zr1—C753.7 (3)C9—C10—C6107.7 (8)
C10i—Zr1—C7130.2 (3)C9—C10—Zr173.9 (5)
C6—Zr1—C732.3 (3)C6—C10—Zr174.2 (5)
C6i—Zr1—C7145.0 (5)C9—C10—H11126.2
C7i—Zr1—C7170.5 (6)C6—C10—H11126.2
O4—Zr1—C8i116.0 (3)Zr1—C10—H11117.7
Symmetry code: (i) x, y+1/2, z.

Experimental details

Crystal data
Chemical formula[ZrW(C5H5)2(C2H3O)Cl(CO)5]
Mr623.79
Crystal system, space groupOrthorhombic, Pnma
Temperature (K)273
a, b, c (Å)22.3794 (8), 12.3852 (7), 7.2404 (3)
V3)2006.85 (16)
Z4
Radiation typeMo Kα
µ (mm1)6.41
Crystal size (mm)0.34 × 0.31 × 0.29
Data collection
DiffractometerPhilips PW1100
diffractometer
Absorption correctionψ scan
(North et al., 1968)
Tmin, Tmax0.219, 0.258
No. of measured, independent and
observed [I > 2σ(I)] reflections
2070, 1851, 1521
Rint0.042
(sin θ/λ)max1)0.594
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.032, 0.092, 1.08
No. of reflections1851
No. of parameters131
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)1.15, 1.14

Computer programs: PWPC (Gomm, 1998), Xtal3.4 (Hall et al., 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001; Atwood & Barbour, 2003), publCIF (Westrip, 2008).

Selected geometric parameters (Å, º) top
W1—C42.192 (9)O4—C41.270 (10)
Zr1—O42.026 (6)
C4—O4—Zr1177.4 (7)
 

Footnotes

Currently at Sasol Technology, PO Box 1, Sasolburg 1947, South Africa.

§Currently at Sasol Polymers, PO Box 72, Modderfontein 1645, South Africa.

Acknowledgements

We thank the NRF and the University of Stellenbosch for financial support.

References

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