supplementary materials


HTML versionpdf versioncif file3d viewstructure factorssupplementary materialsCIF check reportcited insimilar papers Open access

Acta Cryst. (2009). E65, m1307    [ doi:10.1107/S1600536809039804 ]

Dichloridobis{N-[(dimethylamino)dimethylsilyl]-2,6-dimethylanilido-[kappa]2N,N'}zirconium(IV)

J. Chen

Abstract top

The monomeric title zirconium(IV) compound, [Zr(C12H21N2Si)2Cl2], was prepared by the metathetical reaction of [LiN(SiMe2NMe2)(2,6-Me2C6H3)]2 with zirconium tetrachloride. The ZrIV atom is N,N'-chelated by the N-silylated anilido ligand. Along with two Cl atoms, the six-coordinated ZrIV atom demonstrates a highly distorted octahedral geometry. The two ligands around the ZrIV atom are arranged cis to each other and obey the C2 symmetry operation. That means the asymmetric unit consists of only half of the molecular compound and the complete molecule is generated by a twofold axis. The two ends of the N-Si-N chelating unit exhibit different affinities for the metal center. The Zr-Namino bond is longer than the Zr-Nanilido bond.

Comment top

Group 4 metal amides supported with the N-silylated anilido ligands were active catalysts for olefin polymerization (Gibson et al., 1998; Hill & Hitchcock, 2002). The N-silylated anilido ligand in the title compound has a pendant amino group. It results in an N—Si—N chelating moiety, which is presumed to be a "quasi" conjugated unit owing to d–π interaction between Si and N atoms. The zinc compound coordinated with the analogous ligand has been reported by Schumann et al. (2000). The title compound is monomeric and contains two N-silylated anilido ligands, which give the N—Zr—N bite angle of 67.63° and are arranged cis to each other and obey the C2 symmetrical operation. That means the asymmetric unit consists of only half of the molecular compound and the complete molecule is generated by a twofold axis. The ZrIV atom is situated in the plane defined by atoms N1, N2A and Cl1, and the symmetrical counterparts. Both planes are perpendicular to each other resulting in a highly distorted octahedral geometry. Two ends of the N—Si—N chelating unit exhibit different affinity to the metal center. The Zr—Nanilido bond is 2.119 Å and the Zr—Namino bond is 2.439 Å, suggesting the former is much tighter than the latter.

Related literature top

For the catalytic applications of related N-silylated analido group 4 metal compounds towards olefin polymerization, see: Gibson et al. (1998); Hill & Hitchcock (2002). For related organometallic compounds supported with analogous analido ligands, see: Schumann et al. (2000); Chen et al. (2007); Ferreira et al. (2007); Chen (2008).

Experimental top

ZrCl4 (0.47 g, 2.03 mmol) was added into the solution of [LiN(SiMe2NMe2)(2,6-Me2C6H3)]2 (0.92 g, 2.03 mmol) in Et2O (30 ml) at 273 K. The reaction mixture was warmed to room temperature and kept stirring for 12 h. It was dried in vacuum to remove all volatiles and the residue was extracted with CH2Cl2 (30 ml). Concentration of the filtrate under reduced pressure gave the title compound as colorless crystals (yield 0.92 g, 75%).

Refinement top

The methyl H atoms were constrained to an ideal geometry, with C—H distances of 0.97 Å and Uiso(H) = 1.5Ueq(C), but each group was allowed to rotate freely about its C–C, C–N and C–Si bonds. The other H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms, with C—H distances in the range 0.94Å and Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL/PC (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. Hydrogens omitted for clarity. Symmetry codes: (i) -x, y, -z + 1/2.
Dichloridobis{N-[(dimethylamino)dimethylsilyl]-2,6-dimethylanilido- κ2N,N'}zirconium(IV) top
Crystal data top
[Zr(C12H21N2Si)2Cl2]F(000) = 1264
Mr = 604.92Dx = 1.393 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 3803 reflections
a = 16.179 (2) Åθ = 2.3–27.1°
b = 10.257 (2) ŵ = 0.67 mm−1
c = 18.779 (4) ÅT = 203 K
β = 112.234 (4)°Block, colorless
V = 2884.6 (9) Å30.20 × 0.20 × 0.20 mm
Z = 4
Data collection top
Bruker SMART area-detector
diffractometer		2548 independent reflections
Radiation source: fine-focus sealed tube2448 reflections with I > 2σ(I)
graphiteRint = 0.027
φ and ω scansθmax = 25.0°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −19→19
Tmin = 0.757, Tmax = 0.878k = −12→12
6014 measured reflectionsl = −18→22
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)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.120H-atom parameters constrained
S = 1.20 w = 1/[σ2(Fo2) + (0.0465P)2 + 9.9576P]
where P = (Fo2 + 2Fc2)/3
2548 reflections(Δ/σ)max < 0.001
151 parametersΔρmax = 0.52 e Å−3
0 restraintsΔρmin = −0.53 e Å−3
Crystal data top
[Zr(C12H21N2Si)2Cl2]V = 2884.6 (9) Å3
Mr = 604.92Z = 4
Monoclinic, C2/cMo Kα radiation
a = 16.179 (2) ŵ = 0.67 mm−1
b = 10.257 (2) ÅT = 203 K
c = 18.779 (4) Å0.20 × 0.20 × 0.20 mm
β = 112.234 (4)°
Data collection top
Bruker SMART area-detector
diffractometer		2548 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		2448 reflections with I > 2σ(I)
Tmin = 0.757, Tmax = 0.878Rint = 0.027
6014 measured reflectionsθmax = 25.0°
Refinement top
R[F2 > 2σ(F2)] = 0.048H-atom parameters constrained
wR(F2) = 0.120Δρmax = 0.52 e Å−3
S = 1.20Δρmin = −0.53 e Å−3
2548 reflectionsAbsolute structure: ?
151 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
Zr10.00000.26497 (5)0.25000.02462 (18)
Si1−0.03902 (7)0.19837 (11)0.39184 (6)0.0297 (3)
Cl1−0.10371 (7)0.42525 (10)0.16362 (7)0.0427 (3)
N10.01144 (19)0.1249 (3)0.33620 (17)0.0249 (7)
N2−0.0992 (2)0.3112 (3)0.3175 (2)0.0337 (8)
C10.0574 (2)0.0027 (3)0.3583 (2)0.0236 (8)
C20.1508 (2)−0.0007 (4)0.3993 (2)0.0278 (8)
C30.1939 (3)−0.1203 (4)0.4175 (2)0.0325 (9)
H3A0.2562−0.12220.44390.039*
C40.1478 (3)−0.2359 (4)0.3977 (2)0.0345 (9)
H4A0.1782−0.31590.40990.041*
C50.0562 (3)−0.2329 (4)0.3598 (2)0.0330 (9)
H5A0.0245−0.31180.34680.040*
C60.0100 (2)−0.1158 (4)0.3404 (2)0.0265 (8)
C70.2058 (3)0.1209 (4)0.4260 (3)0.0416 (11)
H7A0.26800.09740.45270.062*
H7B0.18510.16880.46070.062*
H7C0.19980.17500.38200.062*
C8−0.0900 (2)−0.1221 (4)0.3002 (2)0.0314 (9)
H8A−0.1059−0.19360.26360.047*
H8B−0.1118−0.04090.27310.047*
H8C−0.1169−0.13600.33780.047*
C9−0.1136 (3)0.0973 (4)0.4237 (3)0.0404 (10)
H9A−0.09870.11030.47830.061*
H9B−0.10590.00610.41400.061*
H9C−0.17520.12250.39550.061*
C100.0358 (3)0.2854 (5)0.4793 (3)0.0458 (11)
H10A0.02070.26090.52290.069*
H10B0.02840.37870.47110.069*
H10C0.09740.26180.48970.069*
C11−0.1893 (3)0.2614 (5)0.2688 (3)0.0478 (12)
H11A−0.23050.27840.29410.072*
H11D−0.18600.16830.26130.072*
H11C−0.21000.30510.21940.072*
C12−0.1088 (4)0.4470 (5)0.3400 (3)0.0536 (13)
H12B−0.15030.44920.36610.080*
H12C−0.13120.50130.29440.080*
H12A−0.05110.47940.37420.080*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Zr10.0262 (3)0.0198 (3)0.0309 (3)0.0000.0142 (2)0.000
Si10.0310 (6)0.0305 (6)0.0303 (6)0.0019 (4)0.0148 (5)−0.0011 (4)
Cl10.0491 (6)0.0310 (6)0.0538 (7)0.0120 (5)0.0259 (6)0.0139 (5)
N10.0206 (15)0.0262 (17)0.0273 (17)0.0006 (12)0.0086 (13)−0.0026 (13)
N20.0347 (19)0.0300 (19)0.041 (2)0.0072 (15)0.0194 (16)0.0046 (15)
C10.0258 (18)0.0221 (19)0.0225 (18)0.0028 (15)0.0086 (15)−0.0003 (15)
C20.0254 (19)0.033 (2)0.025 (2)−0.0016 (16)0.0107 (16)−0.0034 (16)
C30.028 (2)0.043 (2)0.026 (2)0.0095 (18)0.0101 (17)0.0027 (18)
C40.040 (2)0.032 (2)0.033 (2)0.0104 (18)0.0139 (19)0.0052 (18)
C50.041 (2)0.026 (2)0.033 (2)−0.0030 (18)0.0150 (19)0.0014 (17)
C60.0272 (19)0.032 (2)0.0221 (19)−0.0027 (16)0.0113 (16)−0.0016 (16)
C70.026 (2)0.043 (3)0.047 (3)−0.0042 (19)0.0039 (19)−0.006 (2)
C80.028 (2)0.035 (2)0.032 (2)−0.0067 (17)0.0127 (18)−0.0042 (17)
C90.047 (3)0.042 (3)0.041 (3)0.002 (2)0.027 (2)0.002 (2)
C100.053 (3)0.050 (3)0.034 (2)−0.005 (2)0.017 (2)−0.012 (2)
C110.031 (2)0.060 (3)0.052 (3)0.009 (2)0.016 (2)0.019 (2)
C120.072 (3)0.039 (3)0.073 (4)0.017 (2)0.053 (3)0.006 (2)
Geometric parameters (Å, °) top
Zr1—N1i2.119 (3)C5—C61.389 (6)
Zr1—N12.119 (3)C5—H5A0.9400
Zr1—N2i2.439 (3)C6—C81.506 (5)
Zr1—N22.439 (3)C7—H7A0.9700
Zr1—Cl1i2.4676 (11)C7—H7B0.9700
Zr1—Cl12.4676 (11)C7—H7C0.9700
Zr1—Si1i3.0385 (12)C8—H8A0.9700
Si1—N11.724 (3)C8—H8B0.9700
Si1—N21.791 (4)C8—H8C0.9700
Si1—C91.854 (4)C9—H9A0.9700
Si1—C101.859 (5)C9—H9B0.9700
N1—C11.436 (5)C9—H9C0.9700
N2—C121.480 (6)C10—H10A0.9700
N2—C111.487 (6)C10—H10B0.9700
C1—C61.408 (5)C10—H10C0.9700
C1—C21.413 (5)C11—H11A0.9700
C2—C31.388 (6)C11—H11D0.9700
C2—C71.504 (6)C11—H11C0.9700
C3—C41.376 (6)C12—H12B0.9700
C3—H3A0.9400C12—H12C0.9700
C4—C51.379 (6)C12—H12A0.9700
C4—H4A0.9400
N1i—Zr1—N194.65 (16)C3—C4—C5119.2 (4)
N1i—Zr1—N2i67.63 (11)C3—C4—H4A120.4
N1—Zr1—N2i130.12 (12)C5—C4—H4A120.4
N1i—Zr1—N2130.12 (12)C4—C5—C6121.4 (4)
N1—Zr1—N267.63 (11)C4—C5—H5A119.3
N2i—Zr1—N2157.56 (16)C6—C5—H5A119.3
N1i—Zr1—Cl1i142.64 (8)C5—C6—C1119.5 (3)
N1—Zr1—Cl1i96.22 (9)C5—C6—C8117.7 (4)
N2i—Zr1—Cl1i78.14 (8)C1—C6—C8122.8 (3)
N2—Zr1—Cl1i86.92 (9)C2—C7—H7A109.5
N1i—Zr1—Cl196.22 (9)C2—C7—H7B109.5
N1—Zr1—Cl1142.64 (8)H7A—C7—H7B109.5
N2i—Zr1—Cl186.92 (9)C2—C7—H7C109.5
N2—Zr1—Cl178.14 (8)H7A—C7—H7C109.5
Cl1i—Zr1—Cl196.45 (6)H7B—C7—H7C109.5
N1i—Zr1—Si1i33.40 (8)C6—C8—H8A109.5
N1—Zr1—Si1i122.01 (9)C6—C8—H8B109.5
N2i—Zr1—Si1i36.12 (8)H8A—C8—H8B109.5
N2—Zr1—Si1i153.54 (9)C6—C8—H8C109.5
Cl1i—Zr1—Si1i114.26 (3)H8A—C8—H8C109.5
Cl1—Zr1—Si1i83.61 (4)H8B—C8—H8C109.5
N1—Si1—N293.02 (16)Si1—C9—H9A109.5
N1—Si1—C9117.81 (19)Si1—C9—H9B109.5
N2—Si1—C9112.64 (19)H9A—C9—H9B109.5
N1—Si1—C10116.49 (19)Si1—C9—H9C109.5
N2—Si1—C10111.0 (2)H9A—C9—H9C109.5
C9—Si1—C10105.6 (2)H9B—C9—H9C109.5
C1—N1—Si1121.2 (2)Si1—C10—H10A109.5
C1—N1—Zr1134.3 (2)Si1—C10—H10B109.5
Si1—N1—Zr1104.01 (15)H10A—C10—H10B109.5
C12—N2—C11108.4 (4)Si1—C10—H10C109.5
C12—N2—Si1118.1 (3)H10A—C10—H10C109.5
C11—N2—Si1112.0 (3)H10B—C10—H10C109.5
C12—N2—Zr1119.4 (3)N2—C11—H11A109.5
C11—N2—Zr1107.3 (3)N2—C11—H11D109.5
Si1—N2—Zr190.49 (13)H11A—C11—H11D109.5
C6—C1—C2118.9 (3)N2—C11—H11C109.5
C6—C1—N1120.6 (3)H11A—C11—H11C109.5
C2—C1—N1120.6 (3)H11D—C11—H11C109.5
C3—C2—C1119.4 (4)N2—C12—H12B109.5
C3—C2—C7118.1 (3)N2—C12—H12C109.5
C1—C2—C7122.5 (3)H12B—C12—H12C109.5
C4—C3—C2121.6 (4)N2—C12—H12A109.5
C4—C3—H3A119.2H12B—C12—H12A109.5
C2—C3—H3A119.2H12C—C12—H12A109.5
Symmetry codes: (i) −x, y, −z+1/2.
Table 1
Selected geometric parameters (Å) top
Zr1—N12.119 (3)Zr1—Cl12.4676 (11)
Zr1—N22.439 (3)
Acknowledgements top

This work was under the sponsorship of the Natural Science Foundation of Shanxi Province (2008011024).

references
References top

Bruker (2000). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.

Chen, J. (2008). Acta Cryst. E64, m938.

Chen, J., Cao, K.-N. & Guo, J. (2007). Acta Cryst. E63, m3112.

Ferreira, H., Dias, A. R., Duarte, M. T., Ascenso, J. R. & Martins, A. M. (2007). Inorg. Chem. 46, 750–755.

Gibson, V. C., Kimberley, B. S., White, A. J. P., Willianms, D. J. & Howard, P. (1998). Chem. Commun. pp. 313–314.

Hill, M. S. & Hitchcock, P. B. (2002). Organometallics, 21, 3258–3262.

Schumann, H., Gottfriedsen, J., Dechert, S. & Girgsdies, F. (2000). Z. Anorg. Allg. Chem. 626, 747–758.

Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.