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Acta Crystallogr Sect E Struct Rep Online. 2010 September 1; 66(Pt 9): m1180.
Published online 2010 August 28. doi:  10.1107/S1600536810033556
PMCID: PMC3007953

(tert-Butyl­imido)bis­(η5-cyclo­penta­dien­yl)pyridine­zirconium(IV)

Abstract

The title compound, [Zr(C5H5)2(C4H9N)(C5H5N)], was obtained from the reaction of (C5H5)2Zr(py)(η2-Me3SiC2SiMe3) (py is pyridine) and tBuN=C=NtBu alongside the formation of (C5H5)2Zr(CNtBu)(η2-Me3SiC2SiMe3). The zirconium atom is coordinated in a distorted tetra­hedral geometry by two cyclo­penta­dienyl ligands, a pyridine ligand, and a tert-butyl­imido ligand via a Zr=N double bond. The tert-butyl group is disordered over two positions in a 0.634 (5):0.366 (5) ratio.

Related literature

For other metallocene complexes (C5H5)CpM(L)(NtBu) (Cp = C5H5, C5Me5; M = Ti, L = py; M = Zr, L = py, thf (thf is tetrahydrofuran), exo-norbornene oxide) with an M=N double bond, see: Blum et al. (2003 [triangle], 2005 [triangle]); Dunn et al. (1997 [triangle]); Krska et al. (1998 [triangle]); Walsh et al. (1988 [triangle], 1993 [triangle]); Zuckerman et al. (2000 [triangle]). For the structure of (rac-ebthi)Zr(py)(NtBu) (ebthi = ethyl­enebis(η5-tetra­hydro­inden­yl)), see: Hoyt et al. (2004 [triangle]). For the preparation of the starting material (C5H5)2Zr(py)(η2-Me3SiC2SiMe3), see: Rosenthal et al. (1995 [triangle]). For the characterization of the by-product (C5H5)2Zr(CNtBu)(η2-Me3SiC2SiMe3) of the above-described reaction, see: Bach et al. (2007 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-m1180-scheme1.jpg

Experimental

Crystal data

  • [Zr(C5H5)2(C4H9N)(C5H5N)]
  • M r = 371.62
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-66-m1180-efi1.jpg
  • a = 9.3946 (2) Å
  • b = 13.6156 (4) Å
  • c = 14.4126 (3) Å
  • V = 1843.56 (8) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.60 mm−1
  • T = 200 K
  • 0.50 × 0.50 × 0.35 mm

Data collection

  • Stoe IPDS II diffractometer
  • Absorption correction: numerical (X-SHAPE and X-RED32; Stoe & Cie, 2005 [triangle]) T min = 0.730, T max = 0.896
  • 35444 measured reflections
  • 4990 independent reflections
  • 4752 reflections with I > 2σ(I)
  • R int = 0.025

Refinement

  • R[F 2 > 2σ(F 2)] = 0.023
  • wR(F 2) = 0.059
  • S = 1.03
  • 4990 reflections
  • 181 parameters
  • 16 restraints
  • H-atom parameters constrained
  • Δρmax = 0.45 e Å−3
  • Δρmin = −0.38 e Å−3
  • Absolute structure: Flack (1983 [triangle]), 216 Friedel pairs
  • Flack parameter: −0.03 (4)

Data collection: X-AREA (Stoe & Cie, 2005 [triangle]); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: XP in SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXTL.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810033556/im2220sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810033556/im2220Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

We thank our technical staff, in particular Regina Jesse, for assistance. This work was supported by the Deutsche Forschungsgemeinschaft (project No. RO1269/7–2).

supplementary crystallographic information

Comment

We studied the reaction of several carbodiimides with metallocene precursors as (C5H5)2M(η2-Me3SiC2SiMe3) (M = Ti, Zr) to synthesize and characterize new metallacycles with heteroatoms. In this case the reaction revealed a C—N bond cleavage which resulted in two products. Additionally to (C5H5)2Zr(py)(NtBu) the complex (C5H5)2Zr(CNtBu)(η2-Me3SiC2SiMe3) was found which was described by Bach et al. (2007).

The title compound consists of a zirconium center coordinated by two cyclopentadienyl ligands, a stabilizing pyridine and a tert-butyl imido ligand. The geometry at the zirconium atom is distorted tetrahedral (main deviations from the expected value of 109.47° are obtained in N1—Zr1—N2 95.64 (6)° and Cp—Zr1—Cp 123.9°). Bond lengths and angles can be compared to the thf stabilized complex (C5H5)2Zr(thf)(NtBu) described by Walsh et al. (1993). The bond lengths Zr1—N1 with 1.843 (2) Å and N1—C1 with 1.434 (3) Å are not significantly different compared to those of (C5H5)2Zr(thf)(NtBu) (Zr—N 1.826 (4) and N—C 1.449 (6) Å). In the title compound the Zr1—N1—C1 angle of 168.93 (13)° is about 5° smaller than the corresponding angle found for the almost linear tert-butyl imido ligand in (C5H5)2Zr(thf)(NtBu).

Experimental

To a solution of 235 mg (0.5 mmol) (C5H5)2Zr(py)(η2-Me3SiC2SiMe3) in 10 ml of n-hexane was added dropwise 0.1 ml (0.5 mmol) of tBuN=C=NtBu. The reaction mixture was allowed to stand for 16 h. During this period the solution turned red and yellow crystals were formed which were isolated, washed with cold n-hexane and dried in vacuo. Yield: 46% (85 mg, 0.229 mmol).

Refinement

All H atoms were placed in idealized positions with d(C—H) = 0.98 (CH3) and 0.95 Å (CH) and refined using a riding model with Uiso(H) fixed at 1.5 Ueq(C) for CH3 and 1.2 Ueq(C) for CH.

Figures

Fig. 1.
Molecular structure of the title compound showing the atom-labelling scheme. Hydrogen atoms are omitted for clarity. Thermal ellipsoids are drawn at the 30% probability level.

Crystal data

[Zr(C5H5)2(C4H9N)(C5H5N)]F(000) = 768
Mr = 371.62Dx = 1.339 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 11751 reflections
a = 9.3946 (2) Åθ = 2.0–29.6°
b = 13.6156 (4) ŵ = 0.60 mm1
c = 14.4126 (3) ÅT = 200 K
V = 1843.56 (8) Å3Prism, yellow
Z = 40.50 × 0.50 × 0.35 mm

Data collection

Stoe IPDS II diffractometer4990 independent reflections
Radiation source: fine-focus sealed tube4752 reflections with I > 2σ(I)
graphiteRint = 0.025
ω scansθmax = 29.2°, θmin = 2.1°
Absorption correction: numerical (X-SHAPE and X-RED32; Stoe & Cie, 2005)h = −12→12
Tmin = 0.730, Tmax = 0.896k = −18→18
35444 measured reflectionsl = −19→19

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.023H-atom parameters constrained
wR(F2) = 0.059w = 1/[σ2(Fo2) + (0.043P)2 + 0.044P] where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max = 0.001
4990 reflectionsΔρmax = 0.45 e Å3
181 parametersΔρmin = −0.38 e Å3
16 restraintsAbsolute structure: Flack (1983), 2169 Friedel pairs
Primary atom site location: structure-invariant direct methodsFlack parameter: −0.03 (4)

Special details

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)

xyzUiso*/UeqOcc. (<1)
C2A−0.0298 (4)0.5132 (4)0.2054 (4)0.0710 (13)*0.634 (5)
H2A1−0.01980.56910.24770.107*0.634 (5)
H2A2−0.11180.47340.22410.107*0.634 (5)
H2A3−0.04410.53730.14200.107*0.634 (5)
C3A0.1191 (6)0.4163 (4)0.3089 (2)0.0765 (14)*0.634 (5)
H3A10.12430.47330.35020.115*0.634 (5)
H3A20.20620.37720.31520.115*0.634 (5)
H3A30.03660.37600.32560.115*0.634 (5)
C4A0.0964 (5)0.3633 (3)0.1445 (3)0.0690 (13)*0.634 (5)
H4A10.18460.32530.14930.103*0.634 (5)
H4A20.08410.38620.08060.103*0.634 (5)
H4A30.01550.32190.16200.103*0.634 (5)
C2B0.0023 (10)0.4490 (9)0.1272 (6)0.095 (3)*0.366 (5)
H2B10.05280.42620.07170.143*0.366 (5)
H2B2−0.03480.51530.11620.143*0.366 (5)
H2B3−0.07690.40440.14080.143*0.366 (5)
C3B0.0215 (10)0.4865 (7)0.2929 (5)0.081 (3)*0.366 (5)
H3B1−0.00460.55560.28430.122*0.366 (5)
H3B20.08060.47990.34860.122*0.366 (5)
H3B3−0.06500.44700.30010.122*0.366 (5)
C4B0.1428 (12)0.3436 (3)0.2234 (6)0.078 (2)*0.366 (5)
H4B10.19740.32000.17000.117*0.366 (5)
H4B20.05560.30470.22970.117*0.366 (5)
H4B30.20030.33700.27980.117*0.366 (5)
C10.1041 (2)0.45092 (16)0.20903 (15)0.0500 (5)
C150.6237 (2)0.54813 (15)0.02869 (15)0.0469 (4)
H150.65090.61420.04030.056*
C160.7109 (3)0.49094 (19)−0.02490 (19)0.0627 (7)
H160.79640.5172−0.04980.075*
C170.6736 (3)0.39523 (18)−0.04233 (19)0.0737 (9)
H170.73320.3538−0.07840.088*
C180.5476 (3)0.36108 (19)−0.00621 (19)0.0722 (9)
H180.51810.2955−0.01810.087*
C190.4643 (3)0.42177 (15)0.04710 (15)0.0493 (5)
H190.37760.39700.07170.059*
N10.22557 (16)0.51038 (11)0.18718 (11)0.0361 (3)
N20.50127 (18)0.51501 (12)0.06570 (11)0.0383 (3)
Zr10.363638 (15)0.605190 (11)0.172085 (11)0.03033 (5)
C50.16807 (18)0.72069 (14)0.12010 (16)0.0645 (8)
H50.07710.70760.14620.077*
C60.2709 (2)0.78328 (13)0.15691 (17)0.0720 (9)
H60.26250.82040.21250.086*
C70.3884 (2)0.78188 (13)0.09794 (17)0.0748 (9)
H70.47410.81790.10620.090*
C80.3582 (2)0.71844 (15)0.02469 (14)0.0712 (8)
H80.41970.7036−0.02570.085*
C90.2220 (2)0.68063 (15)0.03839 (14)0.0680 (8)
H90.17430.6355−0.00110.082*
C100.5757 (3)0.54733 (18)0.27310 (18)0.0803 (10)
H100.62320.48950.25320.096*
C110.4565 (3)0.5510 (2)0.32905 (16)0.0944 (12)
H110.40760.49610.35440.113*
C120.4209 (3)0.6485 (3)0.34173 (13)0.0959 (13)
H120.34310.67240.37730.115*
C130.5180 (3)0.7050 (2)0.29362 (17)0.0829 (10)
H130.51880.77470.29030.099*
C140.6137 (2)0.64251 (19)0.25120 (15)0.0731 (8)
H140.69190.66160.21360.088*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0409 (11)0.0494 (12)0.0596 (12)−0.0060 (8)0.0131 (9)0.0040 (9)
C150.0433 (10)0.0462 (10)0.0513 (11)0.0066 (9)0.0127 (9)0.0041 (8)
C160.0615 (14)0.0656 (15)0.0611 (14)0.0170 (12)0.0308 (12)0.0123 (12)
C170.099 (2)0.0582 (14)0.0644 (15)0.0300 (15)0.0443 (14)0.0062 (13)
C180.116 (2)0.0389 (11)0.0612 (15)0.0142 (13)0.0411 (16)−0.0014 (10)
C190.0687 (14)0.0346 (10)0.0447 (11)0.0026 (8)0.0199 (10)0.0011 (7)
N10.0355 (7)0.0365 (7)0.0364 (8)0.0017 (6)0.0066 (6)0.0008 (6)
N20.0418 (8)0.0357 (8)0.0374 (8)0.0065 (6)0.0085 (6)0.0022 (6)
Zr10.02958 (7)0.03000 (7)0.03142 (7)0.00527 (6)0.00094 (6)−0.00138 (6)
C50.0433 (12)0.0566 (14)0.093 (2)0.0242 (10)0.0149 (11)0.0296 (13)
C60.0713 (16)0.0367 (11)0.108 (3)0.0212 (11)0.0257 (16)0.0057 (13)
C70.0670 (17)0.0398 (11)0.118 (3)0.0089 (11)0.0268 (17)0.0228 (14)
C80.0676 (14)0.0726 (16)0.0735 (16)0.0295 (14)0.0231 (15)0.0402 (14)
C90.0630 (15)0.0719 (17)0.0690 (17)0.0214 (13)−0.0124 (13)0.0270 (14)
C100.0732 (19)0.095 (2)0.0723 (19)0.0222 (17)−0.0423 (17)−0.0064 (17)
C110.104 (3)0.127 (3)0.0521 (15)−0.015 (2)−0.0394 (19)0.020 (2)
C120.086 (2)0.163 (4)0.0385 (14)0.002 (2)−0.0050 (13)−0.0307 (18)
C130.081 (2)0.092 (2)0.0749 (19)−0.0029 (18)−0.0192 (16)−0.0435 (18)
C140.0516 (15)0.101 (2)0.0671 (16)−0.0002 (13)−0.0210 (12)−0.0239 (15)

Geometric parameters (Å, °)

C2A—C11.518 (3)C19—N21.343 (3)
C2A—H2A10.9800C19—H190.9500
C2A—H2A20.9800N1—Zr11.8428 (16)
C2A—H2A30.9800N2—Zr12.3517 (16)
C3A—C11.521 (3)Zr1—C52.5318 (16)
C3A—H3A10.9800Zr1—C112.534 (2)
C3A—H3A20.9800Zr1—C92.5570 (17)
C3A—H3A30.9800Zr1—C122.5719 (19)
C4A—C11.514 (3)Zr1—C62.5857 (17)
C4A—H4A10.9800Zr1—C102.590 (2)
C4A—H4A20.9800Zr1—C82.6255 (17)
C4A—H4A30.9800Zr1—C72.6428 (17)
C2B—C11.519 (3)Zr1—C132.649 (2)
C2B—H2B10.9800Zr1—C142.6602 (19)
C2B—H2B20.9800C5—C61.3933
C2B—H2B30.9800C5—C91.3933
C3B—C11.516 (3)C5—H50.9500
C3B—H3B10.9800C6—C71.3933
C3B—H3B20.9800C6—H60.9500
C3B—H3B30.9800C7—C81.3933
C4B—C11.519 (3)C7—H70.9500
C4B—H4B10.9800C8—C91.3933
C4B—H4B20.9800C8—H80.9500
C4B—H4B30.9800C9—H90.9500
C1—N11.434 (3)C10—C111.3807
C15—N21.346 (3)C10—C141.3807
C15—C161.369 (3)C10—H100.9500
C15—H150.9500C11—C121.3807
C16—C171.373 (3)C11—H110.9500
C16—H160.9500C12—C131.3807
C17—C181.374 (3)C12—H120.9500
C17—H170.9500C13—C141.3807
C18—C191.373 (3)C13—H130.9500
C18—H180.9500C14—H140.9500
C1—C2A—H2A1109.5C5—Zr1—C10155.98 (8)
C1—C2A—H2A2109.5C9—Zr1—C10161.08 (8)
H2A1—C2A—H2A2109.5C12—Zr1—C1051.29 (7)
C1—C2A—H2A3109.5C6—Zr1—C10126.29 (8)
H2A1—C2A—H2A3109.5N1—Zr1—C8119.55 (7)
H2A2—C2A—H2A3109.5N2—Zr1—C877.87 (6)
C1—C3A—H3A1109.5C5—Zr1—C851.80 (6)
C1—C3A—H3A2109.5C11—Zr1—C8154.14 (8)
H3A1—C3A—H3A2109.5C12—Zr1—C8129.69 (9)
C1—C3A—H3A3109.5C6—Zr1—C851.26 (6)
H3A1—C3A—H3A3109.5C10—Zr1—C8130.42 (8)
H3A2—C3A—H3A3109.5N1—Zr1—C7138.37 (7)
C1—C4A—H4A1109.5N2—Zr1—C799.39 (6)
C1—C4A—H4A2109.5C5—Zr1—C751.60 (6)
H4A1—C4A—H4A2109.5C11—Zr1—C7126.55 (9)
C1—C4A—H4A3109.5C9—Zr1—C751.36 (6)
H4A1—C4A—H4A3109.5C12—Zr1—C799.06 (10)
H4A2—C4A—H4A3109.5C10—Zr1—C7115.87 (8)
C1—C2B—H2B1109.5N1—Zr1—C13131.80 (8)
C1—C2B—H2B2109.5N2—Zr1—C13113.45 (7)
H2B1—C2B—H2B2109.5C5—Zr1—C13105.91 (8)
C1—C2B—H2B3109.5C11—Zr1—C1351.00 (7)
H2B1—C2B—H2B3109.5C9—Zr1—C13125.24 (8)
H2B2—C2B—H2B3109.5C6—Zr1—C1376.06 (8)
C1—C3B—H3B1109.5C10—Zr1—C1350.46 (7)
C1—C3B—H3B2109.5C8—Zr1—C13104.14 (9)
H3B1—C3B—H3B2109.5C7—Zr1—C1375.64 (9)
C1—C3B—H3B3109.5N1—Zr1—C14134.81 (8)
H3B1—C3B—H3B3109.5N2—Zr1—C1483.90 (7)
H3B2—C3B—H3B3109.5C5—Zr1—C14130.47 (7)
C1—C4B—H4B1109.5C11—Zr1—C1450.87 (7)
C1—C4B—H4B2109.5C9—Zr1—C14134.89 (8)
H4B1—C4B—H4B2109.5C12—Zr1—C1450.52 (7)
C1—C4B—H4B3109.5C6—Zr1—C1498.89 (7)
H4B1—C4B—H4B3109.5C8—Zr1—C14104.58 (8)
H4B2—C4B—H4B3109.5C7—Zr1—C1485.50 (8)
N1—C1—C4A110.4 (2)C6—C5—C9108.0
N1—C1—C3B113.7 (4)C6—C5—Zr176.34 (7)
C4A—C1—C3B135.8 (5)C9—C5—Zr175.11 (6)
N1—C1—C2A109.7 (2)C6—C5—H5126.0
C4A—C1—C2A112.3 (3)C9—C5—H5126.0
C3B—C1—C2A54.9 (4)Zr1—C5—H5114.8
N1—C1—C2B109.9 (5)C7—C6—C5108.0
C4A—C1—C2B58.6 (5)C7—C6—Zr176.82 (6)
C3B—C1—C2B107.6 (6)C5—C6—Zr172.08 (7)
C2A—C1—C2B57.3 (5)C7—C6—H6126.0
N1—C1—C4B112.5 (4)C5—C6—H6126.0
C4A—C1—C4B48.5 (4)Zr1—C6—H6117.1
C3B—C1—C4B108.7 (6)C8—C7—C6108.0
C2A—C1—C4B137.7 (5)C8—C7—Zr173.98 (6)
C2B—C1—C4B103.9 (6)C6—C7—Zr172.29 (6)
N1—C1—C3A108.0 (3)C8—C7—H7126.0
C4A—C1—C3A109.9 (3)C6—C7—H7126.0
C3B—C1—C3A52.6 (4)Zr1—C7—H7119.6
C2A—C1—C3A106.4 (3)C7—C8—C9108.0
C2B—C1—C3A142.0 (5)C7—C8—Zr175.35 (7)
C4B—C1—C3A63.3 (4)C9—C8—Zr171.71 (6)
N2—C15—C16123.0 (2)C7—C8—H8126.0
N2—C15—H15118.5C9—C8—H8126.0
C16—C15—H15118.5Zr1—C8—H8118.8
C15—C16—C17119.4 (2)C8—C9—C5108.0
C15—C16—H16120.3C8—C9—Zr177.14 (7)
C17—C16—H16120.3C5—C9—Zr173.11 (7)
C16—C17—C18118.2 (2)C8—C9—H9126.0
C16—C17—H17120.9C5—C9—H9126.0
C18—C17—H17120.9Zr1—C9—H9115.9
C19—C18—C17119.9 (2)C11—C10—C14108.0
C19—C18—H18120.0C11—C10—Zr172.15 (8)
C17—C18—H18120.0C14—C10—Zr177.58 (9)
N2—C19—C18122.2 (2)C11—C10—H10126.0
N2—C19—H19118.9C14—C10—H10126.0
C18—C19—H19118.9Zr1—C10—H10116.3
C1—N1—Zr1168.93 (13)C10—C11—C12108.0
C19—N2—C15117.30 (17)C12—C11—Zr175.82 (9)
C19—N2—Zr1118.78 (14)C10—C11—H11126.0
C15—N2—Zr1123.60 (14)C12—C11—H11126.0
N1—Zr1—N295.64 (6)Zr1—C11—H11113.9
N1—Zr1—C587.67 (7)C13—C12—C11108.0
N2—Zr1—C5122.03 (7)C13—C12—Zr177.79 (8)
N1—Zr1—C1186.16 (8)C11—C12—Zr172.82 (9)
N2—Zr1—C11103.93 (9)C13—C12—H12126.0
C5—Zr1—C11134.01 (9)C11—C12—H12126.0
N1—Zr1—C990.23 (7)Zr1—C12—H12115.5
N2—Zr1—C990.26 (6)C12—C13—C14108.0
N1—Zr1—C12101.27 (8)C12—C13—Zr171.59 (8)
N2—Zr1—C12128.65 (8)C14—C13—Zr175.37 (7)
C5—Zr1—C12106.90 (9)C12—C13—H13126.0
C9—Zr1—C12137.15 (9)C14—C13—H13126.0
N1—Zr1—C6115.46 (7)Zr1—C13—H13118.9
N2—Zr1—C6128.29 (6)C13—C14—C10108.0
C11—Zr1—C6117.67 (9)C13—C14—Zr174.49 (8)
C9—Zr1—C652.00 (6)C10—C14—Zr171.97 (8)
C12—Zr1—C686.33 (9)C13—C14—H14126.0
N1—Zr1—C10105.18 (8)C10—C14—H14126.0
N2—Zr1—C1077.57 (8)Zr1—C14—H14119.4

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: IM2220).

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