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Acta Cryst. (2009). E65, m125    [ doi:10.1107/S1600536808042621 ]

Pentacarbonyl-2[kappa]5C-chlorido-1[kappa]Cl-bis[1([eta]5)-cyclopentadienyl]([mu]-1-oxidoethylene-1:2[kappa]2O:C)chromium(0)zirconium(IV)

C. Esterhuysen, L. Retief, G. J. Kruger, S. Cronje and H. G. Raubenheimer

Abstract top

The title compound, [CrZr(C5H5)2(C2H3O)Cl(CO)5], consists of two metal centres, with a (pentacarbonylchromium)oxymethylcarbene group coordinating as a monodentate ligand to the zirconocene chloride. [pi]-Delocalization through the Zr-O-C=Cr unit is indicated by a short Zr-O distance [2.041 (3) Å] and a nearly linear Zr-O-C angle [170.5 (3)°]. Molecules are aligned with their molecular planes (through Zr, Cl, carbene and Cr) parallel to the ab plane. C-H...Cl interactions result in zigzag chains of molecules propagating parallel to the b axis.

Comment top

Since Cp2TiCl2 was shown to polymerize ethylene when activated by methylaluminoxane, MAO (Sinn et al., 1980), derivatives of this compound have been synthesized where a Cl ligand was replaced by a monodentate anionic Fischer-type carbene ligand (Barluenga and Fañanás, 2000). We have shown that zirconocene equivalents of this family of homogeneous catalysts, Cp2Zr(Cl)OC(R)M(CO)5 (where M = W or Cr), catalyze 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, (I).

In the molecular structure the Zr—O and O—C distances are similar to those found in the equivalent tungsten pentacarbonyl complex (Esterhuysen, Nel & Cronje, 2008). The Zr—O—C angle, on the other hand, is less linear than the previously published tungsten structure [177.4 (7)°], but similar to the hafnocene complex W(CO)5C(C6H5)OHf(C5H5)2Cl (Esterhuysen, Neveling et al., 2008), where the Hf—O—C angle deviates slightly more from linearity [171.4 (3)°]. These results are indicative of π delocalization through the Zr—O—C = W unit.

Molecules are linked by C—H···Cl interactions into zigzag chains along the b axis. All molecules in a chain point in the same direction, with their molecular planes parallel. Neighbouring chains in the a-direction have the same orientation, thus forming a layer parallel to the ab-plane. Molecules in neighbouring layers in the c-direction have alternating orientations.

Related literature top

For related literature regarding catalytic data of the title compound, see: Sinn et al. (1980); Luruli et al. (2004, 2006). For other cases of anionic Fischer-type carbenes being used as monodentate ligands, see: Barluenga & Fañanás (2000). For comparable structures, see: Esterhuysen, Nel & Cronje (2008); Esterhuysen, Neveling et al. (2008).

Experimental top

A solution of LiCH3 (11 ml, 1.5M in diethylether, 16.5 mmol) in 10 ml diethylether was added to a well stirred suspension of Cr(CO)6 (3.30 g, 15.0 mmol) in 100 ml of diethylether over the period of 1.5 h. The mixture was stripped of solvent in vacuo. The residue was dried for 3 h, extracted with cold (273 K), degassed water (1 × 40 ml, 2 × 20 ml) and the formed solution filtered. The aqueous solution was treated with a solution of [NEt4]Cl (2.49 g, 15 mmol) in cold, degassed water (4 ml) and the formed precipitate was isolated and dried overnight in vacuo. The precipitate was dissolved in warm CH2Cl2 (5 ml) layered with penatne and cooled to 258 K to yield yellow crystals of (CO)5Cr{=C(Me)O}[NEt4]. A solution of 0.61 g (2.0 mmol) of the product in 30 ml of CH2Cl2 was added to a solution of Cp2ZrCl2 (0.58 g, 2.0 mmol) in 70 ml of diethylether at 233 K over a period of 40 min. AgBF4 (0.39 g, 2.0 mmol) was then added to the mixture and stirred for an hour at 233 K. After reaching room temperature the solvent was removed in vacuo and the residue extracted in 5 portions of 10 ml of toluene. The extract was filtered, and the filtrate dried over anhydrous MgSO4. The solution was layered with pentane and kept at 258 K to yield orange crystals suitable for X-ray diffraction analysis.

Refinement top

H atoms were positioned geometrically, with C—H = 0.95 Å and 0.98 Å, and constrained to ride on their parent atoms, with Uiso(H) = 1.2 or 1.5Ueq(C). Large anisotropy on atoms C16 and C17 suggests the presence of disorder in the C13–C17 Cp ring, however this could not be modeled. Highest peak: 1.03 Å from Zr1; deepest hole: 1.04 Å from Zr1.

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, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) showing the atomic labelling scheme and displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. A portion of the packing diagram showing zigzag chains of molecules forming a layer perpendicular to the c axis.
Pentacarbonyl-2κ5C-chlorido-1κCl-bis[1(η5)-cyclopentadienyl](µ-1- oxidoethylene-1:2κ2O:C)chromiumzirconium top
Crystal data top
[CrZr(C5H5)2(C2H3O)Cl(CO)5]F(000) = 976
Mr = 491.94Dx = 1.686 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 48 reflections
a = 12.7395 (7) Åθ = 2–17°
b = 12.1117 (6) ŵ = 1.26 mm−1
c = 12.7859 (7) ÅT = 173 K
β = 100.826 (5)°Plate, orange
V = 1937.71 (18) Å30.30 × 0.28 × 0.08 mm
Z = 4
Data collection top
Philips PW1100
diffractometer		2332 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.0000
graphiteθmax = 25.0°, θmin = 2.3°
ω–2θ scansh = −15→14
Absorption correction: ψ scan
(North et al., 1968)		k = 0→14
Tmin = 0.68, Tmax = 0.88l = 0→15
3423 measured reflections3 standard reflections every 50 reflections
3423 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)] = 0.039Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.109H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.053P)2]
where P = (Fo2 + 2Fc2)/3
3423 reflections(Δ/σ)max < 0.001
235 parametersΔρmax = 0.55 e Å−3
0 restraintsΔρmin = −0.58 e Å−3
Crystal data top
[CrZr(C5H5)2(C2H3O)Cl(CO)5]V = 1937.71 (18) Å3
Mr = 491.94Z = 4
Monoclinic, P21/cMo Kα radiation
a = 12.7395 (7) ŵ = 1.26 mm−1
b = 12.1117 (6) ÅT = 173 K
c = 12.7859 (7) Å0.30 × 0.28 × 0.08 mm
β = 100.826 (5)°
Data collection top
Philips PW1100
diffractometer		2332 reflections with I > 2σ(I)
Absorption correction: ψ scan
(North et al., 1968)		Rint = 0.0000
Tmin = 0.68, Tmax = 0.88θmax = 25.0°
3423 measured reflections3 standard reflections every 50 reflections
3423 independent reflections intensity decay: none
Refinement top
R[F2 > 2σ(F2)] = 0.039H-atom parameters constrained
wR(F2) = 0.109Δρmax = 0.55 e Å−3
S = 1.06Δρmin = −0.58 e Å−3
3423 reflectionsAbsolute structure: ?
235 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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*/Ueq
Zr10.67690 (3)0.45977 (3)0.79870 (3)0.03838 (16)
Cr20.82371 (6)0.82936 (6)0.79664 (6)0.0441 (2)
Cl10.51592 (14)0.56328 (16)0.80604 (18)0.1054 (7)
O10.6062 (3)0.7896 (4)0.6561 (3)0.0785 (12)
O20.7878 (4)1.0760 (3)0.7936 (4)0.1005 (16)
O30.7167 (4)0.7914 (4)0.9852 (4)0.1065 (17)
O40.9358 (4)0.8437 (4)0.6086 (4)0.0886 (14)
O51.0309 (4)0.8682 (5)0.9517 (4)0.1162 (19)
O60.7769 (3)0.5916 (3)0.8006 (3)0.0532 (9)
C10.6880 (4)0.8052 (4)0.7069 (4)0.0492 (12)
C20.8007 (5)0.9823 (5)0.7944 (4)0.0631 (15)
C30.7572 (5)0.8072 (5)0.9152 (5)0.0627 (15)
C40.8933 (4)0.8394 (4)0.6786 (5)0.0566 (13)
C50.9534 (5)0.8515 (5)0.8931 (5)0.0689 (16)
C60.8496 (4)0.6625 (4)0.7962 (4)0.0449 (11)
C70.9547 (4)0.6101 (5)0.7899 (6)0.086 (2)
H7A1.00800.66780.78710.129*
H7B0.94690.56450.72560.129*
H7C0.97800.56390.85280.129*
C80.8066 (5)0.4232 (6)0.9667 (5)0.0733 (18)
H80.87370.45990.97720.088*
C90.7144 (6)0.4611 (5)0.9977 (4)0.0769 (19)
H90.70650.52871.03320.092*
C100.6349 (5)0.3814 (6)0.9672 (4)0.0758 (18)
H100.56350.38500.97870.091*
C110.6779 (6)0.2982 (5)0.9184 (5)0.0762 (19)
H110.64140.23350.88930.091*
C120.7831 (6)0.3228 (5)0.9179 (5)0.0711 (17)
H120.83150.27790.88870.085*
C130.7269 (6)0.4442 (6)0.6179 (5)0.081 (2)
H130.78430.48670.60120.097*
C140.6228 (6)0.4758 (6)0.6006 (5)0.084 (2)
H140.59430.54450.57270.100*
C150.5653 (7)0.3857 (10)0.6326 (6)0.119 (3)
H150.49010.38140.62820.142*
C160.6386 (11)0.3060 (7)0.6711 (6)0.124 (4)
H160.62280.23650.69890.149*
C170.7361 (9)0.3420 (7)0.6632 (5)0.106 (3)
H170.80110.30270.68540.127*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Zr10.0412 (3)0.0306 (2)0.0410 (3)−0.0002 (2)0.00175 (18)0.0023 (2)
Cr20.0464 (5)0.0299 (4)0.0544 (5)0.0011 (3)0.0054 (4)0.0004 (3)
Cl10.0717 (11)0.0871 (13)0.1666 (19)0.0361 (10)0.0464 (12)0.0408 (12)
O10.048 (2)0.097 (3)0.084 (3)0.002 (2)−0.005 (2)0.002 (2)
O20.121 (4)0.035 (2)0.140 (4)0.013 (2)0.013 (3)−0.005 (2)
O30.134 (5)0.122 (4)0.076 (3)0.023 (4)0.053 (3)0.009 (3)
O40.086 (3)0.096 (3)0.094 (3)−0.016 (3)0.042 (3)−0.007 (3)
O50.077 (3)0.118 (4)0.132 (4)−0.015 (3)−0.033 (3)−0.002 (4)
O60.052 (2)0.0333 (18)0.073 (2)−0.0062 (16)0.0079 (17)−0.0001 (16)
C10.058 (3)0.039 (3)0.054 (3)0.008 (2)0.018 (3)0.005 (2)
C20.074 (4)0.041 (3)0.071 (4)0.004 (3)0.007 (3)−0.003 (3)
C30.076 (4)0.055 (3)0.057 (3)0.008 (3)0.010 (3)−0.005 (3)
C40.054 (3)0.045 (3)0.071 (4)−0.008 (3)0.014 (3)0.000 (3)
C50.061 (4)0.052 (3)0.088 (4)−0.007 (3)−0.002 (3)−0.003 (3)
C60.044 (3)0.036 (3)0.052 (3)0.000 (2)0.003 (2)0.002 (2)
C70.048 (3)0.049 (3)0.160 (7)0.008 (3)0.016 (4)0.004 (4)
C80.073 (4)0.076 (4)0.058 (4)−0.007 (4)−0.020 (3)0.016 (3)
C90.115 (6)0.071 (4)0.041 (3)0.015 (4)0.004 (3)−0.011 (3)
C100.083 (5)0.099 (5)0.047 (3)−0.006 (4)0.019 (3)0.015 (3)
C110.124 (6)0.049 (3)0.050 (4)−0.013 (4)0.002 (4)0.014 (3)
C120.084 (5)0.065 (4)0.061 (4)0.026 (4)0.005 (3)0.020 (3)
C130.104 (6)0.093 (5)0.048 (3)−0.021 (4)0.019 (4)−0.003 (3)
C140.100 (5)0.094 (5)0.048 (3)−0.010 (5)−0.007 (3)0.023 (3)
C150.104 (6)0.185 (10)0.053 (4)−0.072 (7)−0.021 (4)−0.008 (5)
C160.232 (12)0.088 (6)0.047 (4)−0.088 (8)0.009 (6)−0.022 (4)
C170.188 (10)0.076 (5)0.058 (4)0.042 (6)0.032 (5)−0.012 (4)
Geometric parameters (Å, °) top
Zr1—O62.041 (3)C6—C71.498 (7)
Zr1—Cl12.4205 (16)C7—H7A0.9800
Zr1—C162.463 (7)C7—H7B0.9800
Zr1—C172.470 (6)C7—H7C0.9800
Zr1—C122.476 (5)C8—C121.373 (8)
Zr1—C112.483 (5)C8—C91.387 (9)
Zr1—C152.490 (6)C8—H80.9500
Zr1—C82.492 (5)C9—C101.400 (9)
Zr1—C92.500 (5)C9—H90.9500
Zr1—C102.503 (5)C10—C111.354 (9)
Zr1—C142.504 (6)C10—H100.9500
Zr1—C132.517 (6)C11—C121.374 (9)
Cr2—C21.875 (6)C11—H110.9500
Cr2—C51.885 (6)C12—H120.9500
Cr2—C31.889 (6)C13—C141.358 (9)
Cr2—C41.892 (6)C13—C171.362 (9)
Cr2—C11.910 (6)C13—H130.9500
Cr2—C62.048 (5)C14—C151.417 (10)
O1—C11.135 (6)C14—H140.9500
O2—C21.146 (6)C15—C161.368 (13)
O3—C31.130 (6)C15—H150.9500
O4—C41.131 (6)C16—C171.338 (12)
O5—C51.141 (7)C16—H160.9500
O6—C61.271 (5)C17—H170.9500
O6—Zr1—Cl197.24 (10)C3—Cr2—C687.6 (2)
O6—Zr1—C16130.2 (3)C4—Cr2—C687.8 (2)
Cl1—Zr1—C16110.7 (3)C1—Cr2—C688.58 (19)
O6—Zr1—C17100.8 (3)C6—O6—Zr1170.5 (3)
Cl1—Zr1—C17134.4 (2)O1—C1—Cr2178.0 (5)
C16—Zr1—C1731.5 (3)O2—C2—Cr2179.2 (6)
O6—Zr1—C12104.4 (2)O3—C3—Cr2178.3 (6)
Cl1—Zr1—C12133.79 (17)O4—C4—Cr2178.7 (5)
C16—Zr1—C1285.4 (3)O5—C5—Cr2177.9 (6)
C17—Zr1—C1280.9 (2)O6—C6—C7112.5 (4)
O6—Zr1—C11132.73 (19)O6—C6—Cr2123.2 (3)
Cl1—Zr1—C11106.9 (2)C7—C6—Cr2124.3 (4)
C16—Zr1—C1177.9 (3)C6—C7—H7A109.5
C17—Zr1—C1190.6 (3)C6—C7—H7B109.5
C12—Zr1—C1132.2 (2)H7A—C7—H7B109.5
O6—Zr1—C15123.2 (2)C6—C7—H7C109.5
Cl1—Zr1—C1582.4 (3)H7A—C7—H7C109.5
C16—Zr1—C1532.1 (3)H7B—C7—H7C109.5
C17—Zr1—C1552.7 (3)C12—C8—C9107.3 (6)
C12—Zr1—C15116.3 (3)C12—C8—Zr173.3 (3)
C11—Zr1—C15100.2 (3)C9—C8—Zr174.2 (3)
O6—Zr1—C879.46 (18)C12—C8—H8126.3
Cl1—Zr1—C8119.22 (18)C9—C8—H8126.3
C16—Zr1—C8117.0 (3)Zr1—C8—H8118.2
C17—Zr1—C8105.2 (3)C8—C9—C10107.4 (6)
C12—Zr1—C832.1 (2)C8—C9—Zr173.5 (3)
C11—Zr1—C853.3 (2)C10—C9—Zr173.9 (3)
C15—Zr1—C8148.3 (3)C8—C9—H9126.3
O6—Zr1—C989.1 (2)C10—C9—H9126.3
Cl1—Zr1—C987.62 (17)Zr1—C9—H9118.3
C16—Zr1—C9130.9 (3)C11—C10—C9107.9 (6)
C17—Zr1—C9133.9 (2)C11—C10—Zr173.4 (3)
C12—Zr1—C953.1 (2)C9—C10—Zr173.6 (3)
C11—Zr1—C953.1 (2)C11—C10—H10126.0
C15—Zr1—C9147.1 (3)C9—C10—H10126.0
C8—Zr1—C932.3 (2)Zr1—C10—H10118.8
O6—Zr1—C10121.38 (19)C10—C11—C12108.6 (6)
Cl1—Zr1—C1081.00 (17)C10—C11—Zr175.1 (3)
C16—Zr1—C10103.6 (3)C12—C11—Zr173.6 (3)
C17—Zr1—C10121.9 (3)C10—C11—H11125.7
C12—Zr1—C1052.9 (2)C12—C11—H11125.7
C11—Zr1—C1031.5 (2)Zr1—C11—H11117.6
C15—Zr1—C10114.7 (3)C8—C12—C11108.7 (6)
C8—Zr1—C1053.5 (2)C8—C12—Zr174.6 (3)
C9—Zr1—C1032.5 (2)C11—C12—Zr174.2 (3)
O6—Zr1—C1490.23 (19)C8—C12—H12125.7
Cl1—Zr1—C1485.7 (2)C11—C12—H12125.7
C16—Zr1—C1453.6 (3)Zr1—C12—H12117.5
C17—Zr1—C1452.9 (3)C14—C13—C17109.2 (7)
C12—Zr1—C14133.6 (2)C14—C13—Zr173.8 (4)
C11—Zr1—C14130.8 (2)C17—C13—Zr172.2 (4)
C15—Zr1—C1433.0 (2)C14—C13—H13125.4
C8—Zr1—C14153.9 (3)C17—C13—H13125.4
C9—Zr1—C14173.1 (2)Zr1—C13—H13120.3
C10—Zr1—C14146.9 (2)C13—C14—C15106.2 (7)
O6—Zr1—C1378.71 (18)C13—C14—Zr174.9 (3)
Cl1—Zr1—C13115.91 (19)C15—C14—Zr173.0 (3)
C16—Zr1—C1352.3 (3)C13—C14—H14126.9
C17—Zr1—C1331.7 (2)C15—C14—H14126.9
C12—Zr1—C13108.2 (2)Zr1—C14—H14117.5
C11—Zr1—C13122.3 (2)C16—C15—C14107.0 (8)
C15—Zr1—C1352.6 (3)C16—C15—Zr172.9 (4)
C8—Zr1—C13122.5 (3)C14—C15—Zr174.1 (4)
C9—Zr1—C13154.5 (3)C16—C15—H15126.5
C10—Zr1—C13153.4 (2)C14—C15—H15126.5
C14—Zr1—C1331.4 (2)Zr1—C15—H15118.6
C2—Cr2—C589.1 (2)C17—C16—C15108.9 (8)
C2—Cr2—C393.4 (2)C17—C16—Zr174.5 (4)
C5—Cr2—C388.0 (3)C15—C16—Zr175.0 (5)
C2—Cr2—C491.1 (2)C17—C16—H16125.5
C5—Cr2—C491.6 (3)C15—C16—H16125.5
C3—Cr2—C4175.4 (2)Zr1—C16—H16116.8
C2—Cr2—C191.2 (2)C16—C17—C13108.7 (9)
C5—Cr2—C1176.2 (2)C16—C17—Zr174.0 (5)
C3—Cr2—C188.2 (2)C13—C17—Zr176.1 (4)
C4—Cr2—C192.2 (2)C16—C17—H17125.7
C2—Cr2—C6178.9 (2)C13—C17—H17125.6
C5—Cr2—C691.2 (2)Zr1—C17—H17116.3
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C16—H16···Cl1i0.952.743.581 (8)149
Symmetry codes: (i) −x+1, y−1/2, −z+3/2.
Table 1
Selected geometric parameters (Å, °) top
Zr1—O62.041 (3)O6—C61.271 (5)
C6—O6—Zr1170.5 (3)
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C16—H16···Cl1i0.952.743.581 (8)149
Symmetry codes: (i) −x+1, y−1/2, −z+3/2.
Acknowledgements top

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

references
References top

Atwood, J. L. & Barbour, L. J. (2003). Cryst. Growth Des. 3, 3–8.

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