metal-organic compounds
Dichloridobis{N-[(dimethylamino)dimethylsilyl]-2,6-dimethylanilido-κ2N,N′}zirconium(IV)
aDepartment of Chemistry, Taiyuan Teachers College, Taiyuan 030031, People's Republic of China
*Correspondence e-mail: sdbai@sxu.edu.cn
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 That means the 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.
Related literature
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
Crystal data
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Refinement
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Data collection: SMART (Bruker, 2000); cell SAINT (Bruker, 2000); data reduction: SAINT; 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.
Supporting information
https://doi.org/10.1107/S1600536809039804/vm2005sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536809039804/vm2005Isup2.hkl
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%).
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).
Group 4 metal 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 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.
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–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).
Data collection: SMART (Bruker, 2000); cell
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).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. |
[Zr(C12H21N2Si)2Cl2] | F(000) = 1264 |
Mr = 604.92 | Dx = 1.393 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 3803 reflections |
a = 16.179 (2) Å | θ = 2.3–27.1° |
b = 10.257 (2) Å | µ = 0.67 mm−1 |
c = 18.779 (4) Å | T = 203 K |
β = 112.234 (4)° | Block, colorless |
V = 2884.6 (9) Å3 | 0.20 × 0.20 × 0.20 mm |
Z = 4 |
Bruker SMART area-detector diffractometer | 2548 independent reflections |
Radiation source: fine-focus sealed tube | 2448 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.027 |
φ and ω scans | θmax = 25.0°, θmin = 2.3° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −19→19 |
Tmin = 0.757, Tmax = 0.878 | k = −12→12 |
6014 measured reflections | l = −18→22 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.048 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.120 | H-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 parameters | Δρmax = 0.52 e Å−3 |
0 restraints | Δρmin = −0.53 e Å−3 |
[Zr(C12H21N2Si)2Cl2] | V = 2884.6 (9) Å3 |
Mr = 604.92 | Z = 4 |
Monoclinic, C2/c | Mo Kα radiation |
a = 16.179 (2) Å | µ = 0.67 mm−1 |
b = 10.257 (2) Å | T = 203 K |
c = 18.779 (4) Å | 0.20 × 0.20 × 0.20 mm |
β = 112.234 (4)° |
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 = 0.878 | Rint = 0.027 |
6014 measured reflections |
R[F2 > 2σ(F2)] = 0.048 | 0 restraints |
wR(F2) = 0.120 | H-atom parameters constrained |
S = 1.20 | Δρmax = 0.52 e Å−3 |
2548 reflections | Δρmin = −0.53 e Å−3 |
151 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
Zr1 | 0.0000 | 0.26497 (5) | 0.2500 | 0.02462 (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) | |
N1 | 0.01144 (19) | 0.1249 (3) | 0.33620 (17) | 0.0249 (7) | |
N2 | −0.0992 (2) | 0.3112 (3) | 0.3175 (2) | 0.0337 (8) | |
C1 | 0.0574 (2) | 0.0027 (3) | 0.3583 (2) | 0.0236 (8) | |
C2 | 0.1508 (2) | −0.0007 (4) | 0.3993 (2) | 0.0278 (8) | |
C3 | 0.1939 (3) | −0.1203 (4) | 0.4175 (2) | 0.0325 (9) | |
H3A | 0.2562 | −0.1222 | 0.4439 | 0.039* | |
C4 | 0.1478 (3) | −0.2359 (4) | 0.3977 (2) | 0.0345 (9) | |
H4A | 0.1782 | −0.3159 | 0.4099 | 0.041* | |
C5 | 0.0562 (3) | −0.2329 (4) | 0.3598 (2) | 0.0330 (9) | |
H5A | 0.0245 | −0.3118 | 0.3468 | 0.040* | |
C6 | 0.0100 (2) | −0.1158 (4) | 0.3404 (2) | 0.0265 (8) | |
C7 | 0.2058 (3) | 0.1209 (4) | 0.4260 (3) | 0.0416 (11) | |
H7A | 0.2680 | 0.0974 | 0.4527 | 0.062* | |
H7B | 0.1851 | 0.1688 | 0.4607 | 0.062* | |
H7C | 0.1998 | 0.1750 | 0.3820 | 0.062* | |
C8 | −0.0900 (2) | −0.1221 (4) | 0.3002 (2) | 0.0314 (9) | |
H8A | −0.1059 | −0.1936 | 0.2636 | 0.047* | |
H8B | −0.1118 | −0.0409 | 0.2731 | 0.047* | |
H8C | −0.1169 | −0.1360 | 0.3378 | 0.047* | |
C9 | −0.1136 (3) | 0.0973 (4) | 0.4237 (3) | 0.0404 (10) | |
H9A | −0.0987 | 0.1103 | 0.4783 | 0.061* | |
H9B | −0.1059 | 0.0061 | 0.4140 | 0.061* | |
H9C | −0.1752 | 0.1225 | 0.3955 | 0.061* | |
C10 | 0.0358 (3) | 0.2854 (5) | 0.4793 (3) | 0.0458 (11) | |
H10A | 0.0207 | 0.2609 | 0.5229 | 0.069* | |
H10B | 0.0284 | 0.3787 | 0.4711 | 0.069* | |
H10C | 0.0974 | 0.2618 | 0.4897 | 0.069* | |
C11 | −0.1893 (3) | 0.2614 (5) | 0.2688 (3) | 0.0478 (12) | |
H11A | −0.2305 | 0.2784 | 0.2941 | 0.072* | |
H11D | −0.1860 | 0.1683 | 0.2613 | 0.072* | |
H11C | −0.2100 | 0.3051 | 0.2194 | 0.072* | |
C12 | −0.1088 (4) | 0.4470 (5) | 0.3400 (3) | 0.0536 (13) | |
H12B | −0.1503 | 0.4492 | 0.3661 | 0.080* | |
H12C | −0.1312 | 0.5013 | 0.2944 | 0.080* | |
H12A | −0.0511 | 0.4794 | 0.3742 | 0.080* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Zr1 | 0.0262 (3) | 0.0198 (3) | 0.0309 (3) | 0.000 | 0.0142 (2) | 0.000 |
Si1 | 0.0310 (6) | 0.0305 (6) | 0.0303 (6) | 0.0019 (4) | 0.0148 (5) | −0.0011 (4) |
Cl1 | 0.0491 (6) | 0.0310 (6) | 0.0538 (7) | 0.0120 (5) | 0.0259 (6) | 0.0139 (5) |
N1 | 0.0206 (15) | 0.0262 (17) | 0.0273 (17) | 0.0006 (12) | 0.0086 (13) | −0.0026 (13) |
N2 | 0.0347 (19) | 0.0300 (19) | 0.041 (2) | 0.0072 (15) | 0.0194 (16) | 0.0046 (15) |
C1 | 0.0258 (18) | 0.0221 (19) | 0.0225 (18) | 0.0028 (15) | 0.0086 (15) | −0.0003 (15) |
C2 | 0.0254 (19) | 0.033 (2) | 0.025 (2) | −0.0016 (16) | 0.0107 (16) | −0.0034 (16) |
C3 | 0.028 (2) | 0.043 (2) | 0.026 (2) | 0.0095 (18) | 0.0101 (17) | 0.0027 (18) |
C4 | 0.040 (2) | 0.032 (2) | 0.033 (2) | 0.0104 (18) | 0.0139 (19) | 0.0052 (18) |
C5 | 0.041 (2) | 0.026 (2) | 0.033 (2) | −0.0030 (18) | 0.0150 (19) | 0.0014 (17) |
C6 | 0.0272 (19) | 0.032 (2) | 0.0221 (19) | −0.0027 (16) | 0.0113 (16) | −0.0016 (16) |
C7 | 0.026 (2) | 0.043 (3) | 0.047 (3) | −0.0042 (19) | 0.0039 (19) | −0.006 (2) |
C8 | 0.028 (2) | 0.035 (2) | 0.032 (2) | −0.0067 (17) | 0.0127 (18) | −0.0042 (17) |
C9 | 0.047 (3) | 0.042 (3) | 0.041 (3) | 0.002 (2) | 0.027 (2) | 0.002 (2) |
C10 | 0.053 (3) | 0.050 (3) | 0.034 (2) | −0.005 (2) | 0.017 (2) | −0.012 (2) |
C11 | 0.031 (2) | 0.060 (3) | 0.052 (3) | 0.009 (2) | 0.016 (2) | 0.019 (2) |
C12 | 0.072 (3) | 0.039 (3) | 0.073 (4) | 0.017 (2) | 0.053 (3) | 0.006 (2) |
Zr1—N1i | 2.119 (3) | C5—C6 | 1.389 (6) |
Zr1—N1 | 2.119 (3) | C5—H5A | 0.9400 |
Zr1—N2i | 2.439 (3) | C6—C8 | 1.506 (5) |
Zr1—N2 | 2.439 (3) | C7—H7A | 0.9700 |
Zr1—Cl1i | 2.4676 (11) | C7—H7B | 0.9700 |
Zr1—Cl1 | 2.4676 (11) | C7—H7C | 0.9700 |
Zr1—Si1i | 3.0385 (12) | C8—H8A | 0.9700 |
Si1—N1 | 1.724 (3) | C8—H8B | 0.9700 |
Si1—N2 | 1.791 (4) | C8—H8C | 0.9700 |
Si1—C9 | 1.854 (4) | C9—H9A | 0.9700 |
Si1—C10 | 1.859 (5) | C9—H9B | 0.9700 |
N1—C1 | 1.436 (5) | C9—H9C | 0.9700 |
N2—C12 | 1.480 (6) | C10—H10A | 0.9700 |
N2—C11 | 1.487 (6) | C10—H10B | 0.9700 |
C1—C6 | 1.408 (5) | C10—H10C | 0.9700 |
C1—C2 | 1.413 (5) | C11—H11A | 0.9700 |
C2—C3 | 1.388 (6) | C11—H11D | 0.9700 |
C2—C7 | 1.504 (6) | C11—H11C | 0.9700 |
C3—C4 | 1.376 (6) | C12—H12B | 0.9700 |
C3—H3A | 0.9400 | C12—H12C | 0.9700 |
C4—C5 | 1.379 (6) | C12—H12A | 0.9700 |
C4—H4A | 0.9400 | ||
N1i—Zr1—N1 | 94.65 (16) | C3—C4—C5 | 119.2 (4) |
N1i—Zr1—N2i | 67.63 (11) | C3—C4—H4A | 120.4 |
N1—Zr1—N2i | 130.12 (12) | C5—C4—H4A | 120.4 |
N1i—Zr1—N2 | 130.12 (12) | C4—C5—C6 | 121.4 (4) |
N1—Zr1—N2 | 67.63 (11) | C4—C5—H5A | 119.3 |
N2i—Zr1—N2 | 157.56 (16) | C6—C5—H5A | 119.3 |
N1i—Zr1—Cl1i | 142.64 (8) | C5—C6—C1 | 119.5 (3) |
N1—Zr1—Cl1i | 96.22 (9) | C5—C6—C8 | 117.7 (4) |
N2i—Zr1—Cl1i | 78.14 (8) | C1—C6—C8 | 122.8 (3) |
N2—Zr1—Cl1i | 86.92 (9) | C2—C7—H7A | 109.5 |
N1i—Zr1—Cl1 | 96.22 (9) | C2—C7—H7B | 109.5 |
N1—Zr1—Cl1 | 142.64 (8) | H7A—C7—H7B | 109.5 |
N2i—Zr1—Cl1 | 86.92 (9) | C2—C7—H7C | 109.5 |
N2—Zr1—Cl1 | 78.14 (8) | H7A—C7—H7C | 109.5 |
Cl1i—Zr1—Cl1 | 96.45 (6) | H7B—C7—H7C | 109.5 |
N1i—Zr1—Si1i | 33.40 (8) | C6—C8—H8A | 109.5 |
N1—Zr1—Si1i | 122.01 (9) | C6—C8—H8B | 109.5 |
N2i—Zr1—Si1i | 36.12 (8) | H8A—C8—H8B | 109.5 |
N2—Zr1—Si1i | 153.54 (9) | C6—C8—H8C | 109.5 |
Cl1i—Zr1—Si1i | 114.26 (3) | H8A—C8—H8C | 109.5 |
Cl1—Zr1—Si1i | 83.61 (4) | H8B—C8—H8C | 109.5 |
N1—Si1—N2 | 93.02 (16) | Si1—C9—H9A | 109.5 |
N1—Si1—C9 | 117.81 (19) | Si1—C9—H9B | 109.5 |
N2—Si1—C9 | 112.64 (19) | H9A—C9—H9B | 109.5 |
N1—Si1—C10 | 116.49 (19) | Si1—C9—H9C | 109.5 |
N2—Si1—C10 | 111.0 (2) | H9A—C9—H9C | 109.5 |
C9—Si1—C10 | 105.6 (2) | H9B—C9—H9C | 109.5 |
C1—N1—Si1 | 121.2 (2) | Si1—C10—H10A | 109.5 |
C1—N1—Zr1 | 134.3 (2) | Si1—C10—H10B | 109.5 |
Si1—N1—Zr1 | 104.01 (15) | H10A—C10—H10B | 109.5 |
C12—N2—C11 | 108.4 (4) | Si1—C10—H10C | 109.5 |
C12—N2—Si1 | 118.1 (3) | H10A—C10—H10C | 109.5 |
C11—N2—Si1 | 112.0 (3) | H10B—C10—H10C | 109.5 |
C12—N2—Zr1 | 119.4 (3) | N2—C11—H11A | 109.5 |
C11—N2—Zr1 | 107.3 (3) | N2—C11—H11D | 109.5 |
Si1—N2—Zr1 | 90.49 (13) | H11A—C11—H11D | 109.5 |
C6—C1—C2 | 118.9 (3) | N2—C11—H11C | 109.5 |
C6—C1—N1 | 120.6 (3) | H11A—C11—H11C | 109.5 |
C2—C1—N1 | 120.6 (3) | H11D—C11—H11C | 109.5 |
C3—C2—C1 | 119.4 (4) | N2—C12—H12B | 109.5 |
C3—C2—C7 | 118.1 (3) | N2—C12—H12C | 109.5 |
C1—C2—C7 | 122.5 (3) | H12B—C12—H12C | 109.5 |
C4—C3—C2 | 121.6 (4) | N2—C12—H12A | 109.5 |
C4—C3—H3A | 119.2 | H12B—C12—H12A | 109.5 |
C2—C3—H3A | 119.2 | H12C—C12—H12A | 109.5 |
Symmetry code: (i) −x, y, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | [Zr(C12H21N2Si)2Cl2] |
Mr | 604.92 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 203 |
a, b, c (Å) | 16.179 (2), 10.257 (2), 18.779 (4) |
β (°) | 112.234 (4) |
V (Å3) | 2884.6 (9) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.67 |
Crystal size (mm) | 0.20 × 0.20 × 0.20 |
Data collection | |
Diffractometer | Bruker SMART area-detector |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.757, 0.878 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6014, 2548, 2448 |
Rint | 0.027 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.048, 0.120, 1.20 |
No. of reflections | 2548 |
No. of parameters | 151 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.52, −0.53 |
Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL/PC (Sheldrick, 2008).
Acknowledgements
This work was under the sponsorship of the Natural Science Foundation of Shanxi Province (2008011024).
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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.