Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536801003415/wn6005sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536801003415/wn6005Isup2.hkl |
CCDC reference: 159871
All H atoms were located by difference Fourier synthesis and refined with fixed individual displacement parameters [U(H) = 1.5 Ueq[C(methyl)] or U(H) = 1.2Ueq(C)] using a riding model with C—H(aromatic) = 0.95, C—H(methyl) = 0.98, or C—H(tertiary) = 1.00 Å. The H atom bonded to Si was refined isotropically applying a restraint of 1.40 (1) Å to the Si—H distance The methyl groups attached to the aromatic rings were allowed to rotate about their local threefold axis.
Data collection: SMART (Siemens, 1995); cell refinement: SMART; data reduction: SAINT (Siemens, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 1991).
C28H34Br2Cl12N4Si | Z = 1 |
Mr = 1039.90 | F(000) = 518 |
Triclinic, P1 | Dx = 1.554 Mg m−3 |
a = 8.840 (1) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 10.059 (1) Å | Cell parameters from 7621 reflections |
c = 13.330 (1) Å | θ = 1–25° |
α = 97.65 (1)° | µ = 2.60 mm−1 |
β = 90.68 (1)° | T = 173 K |
γ = 108.63 (1)° | Block, colourless |
V = 1111.35 (19) Å3 | 0.40 × 0.35 × 0.20 mm |
Siemens CCD three-circle diffractometer | 5095 independent reflections |
Radiation source: fine-focus sealed tube | 3406 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.087 |
ω scans | θmax = 27.5°, θmin = 1.5° |
Absorption correction: empirical (SADABS; Sheldrick, 1996) | h = −11→11 |
Tmin = 0.37, Tmax = 0.60 | k = −13→13 |
22862 measured reflections | l = −17→17 |
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)] = 0.093 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.268 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.11 | w = 1/[σ2(Fo2) + (0.0856P)2 + 12.6187P] where P = (Fo2 + 2Fc2)/3 |
5095 reflections | (Δ/σ)max = 0.002 |
219 parameters | Δρmax = 2.39 e Å−3 |
1 restraint | Δρmin = −0.85 e Å−3 |
C28H34Br2Cl12N4Si | γ = 108.63 (1)° |
Mr = 1039.90 | V = 1111.35 (19) Å3 |
Triclinic, P1 | Z = 1 |
a = 8.840 (1) Å | Mo Kα radiation |
b = 10.059 (1) Å | µ = 2.60 mm−1 |
c = 13.330 (1) Å | T = 173 K |
α = 97.65 (1)° | 0.40 × 0.35 × 0.20 mm |
β = 90.68 (1)° |
Siemens CCD three-circle diffractometer | 5095 independent reflections |
Absorption correction: empirical (SADABS; Sheldrick, 1996) | 3406 reflections with I > 2σ(I) |
Tmin = 0.37, Tmax = 0.60 | Rint = 0.087 |
22862 measured reflections |
R[F2 > 2σ(F2)] = 0.093 | 1 restraint |
wR(F2) = 0.268 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.11 | w = 1/[σ2(Fo2) + (0.0856P)2 + 12.6187P] where P = (Fo2 + 2Fc2)/3 |
5095 reflections | Δρmax = 2.39 e Å−3 |
219 parameters | Δρmin = −0.85 e Å−3 |
Experimental. ; |
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 | ||
Si1 | 0.0000 | 0.5000 | 0.0000 | 0.0181 (6) | |
H1 | 0.095 (8) | 0.592 (6) | −0.062 (5) | 0.022* | |
N11 | 0.1233 (8) | 0.6138 (7) | 0.1258 (5) | 0.0245 (13) | |
C12 | 0.0870 (9) | 0.5698 (9) | 0.2165 (6) | 0.0279 (17) | |
H12 | 0.0024 | 0.4839 | 0.2190 | 0.034* | |
C13 | 0.1699 (10) | 0.6467 (10) | 0.3067 (7) | 0.0346 (19) | |
C131 | 0.1271 (14) | 0.5955 (13) | 0.4048 (8) | 0.059 (3) | |
H13A | 0.0186 | 0.5272 | 0.3978 | 0.088* | |
H13B | 0.1317 | 0.6758 | 0.4565 | 0.088* | |
H13C | 0.2027 | 0.5495 | 0.4250 | 0.088* | |
C14 | 0.2969 (9) | 0.7754 (9) | 0.2986 (6) | 0.0306 (18) | |
H14 | 0.3556 | 0.8321 | 0.3581 | 0.037* | |
C15 | 0.3335 (10) | 0.8167 (9) | 0.2068 (6) | 0.0318 (18) | |
H15 | 0.4190 | 0.9009 | 0.2016 | 0.038* | |
C16 | 0.2460 (9) | 0.7358 (8) | 0.1209 (6) | 0.0278 (17) | |
H16 | 0.2718 | 0.7657 | 0.0568 | 0.033* | |
N21 | 0.1444 (8) | 0.3859 (7) | −0.0114 (5) | 0.0240 (13) | |
C22 | 0.1176 (10) | 0.2725 (8) | 0.0383 (6) | 0.0278 (17) | |
H22 | 0.0270 | 0.2490 | 0.0782 | 0.033* | |
C23 | 0.2159 (11) | 0.1886 (9) | 0.0340 (7) | 0.0350 (19) | |
C231 | 0.1800 (14) | 0.0644 (11) | 0.0918 (8) | 0.050 (3) | |
H23A | 0.2541 | 0.0888 | 0.1517 | 0.075* | |
H23B | 0.1925 | −0.0175 | 0.0482 | 0.075* | |
H23C | 0.0699 | 0.0409 | 0.1131 | 0.075* | |
C24 | 0.3474 (11) | 0.2239 (10) | −0.0254 (8) | 0.040 (2) | |
H24 | 0.4175 | 0.1690 | −0.0308 | 0.048* | |
C25 | 0.3753 (11) | 0.3401 (10) | −0.0768 (7) | 0.040 (2) | |
H25 | 0.4643 | 0.3645 | −0.1179 | 0.048* | |
C26 | 0.2747 (10) | 0.4198 (9) | −0.0683 (6) | 0.0303 (18) | |
H26 | 0.2963 | 0.5001 | −0.1028 | 0.036* | |
C1 | 0.8545 (14) | 0.0240 (12) | 0.3371 (9) | 0.056 (3) | |
H11 | 0.8022 | 0.0465 | 0.2776 | 0.067* | |
Cl11 | 0.9042 (8) | −0.1295 (4) | 0.2984 (4) | 0.1131 (17) | |
Cl12 | 0.7192 (5) | −0.0003 (5) | 0.4349 (4) | 0.1039 (14) | |
Cl13 | 1.0267 (5) | 0.1644 (5) | 0.3757 (4) | 0.0996 (14) | |
C2 | 0.4663 (12) | −0.3654 (11) | 0.6797 (8) | 0.048 (2) | |
H21 | 0.4338 | −0.2974 | 0.7295 | 0.058* | |
Cl21 | 0.2981 (4) | −0.5164 (5) | 0.6433 (3) | 0.0908 (13) | |
Cl22 | 0.6144 (4) | −0.4136 (4) | 0.7382 (3) | 0.0755 (10) | |
Cl23 | 0.5386 (4) | −0.2817 (5) | 0.5741 (3) | 0.0904 (13) | |
Br1 | 0.32492 (12) | 0.85295 (10) | −0.14354 (7) | 0.0387 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Si1 | 0.0192 (13) | 0.0191 (13) | 0.0166 (13) | 0.0062 (11) | 0.0034 (10) | 0.0054 (10) |
N11 | 0.025 (3) | 0.026 (3) | 0.027 (3) | 0.012 (3) | 0.002 (3) | 0.009 (3) |
C12 | 0.026 (4) | 0.031 (4) | 0.027 (4) | 0.008 (3) | 0.007 (3) | 0.010 (3) |
C13 | 0.029 (4) | 0.044 (5) | 0.031 (5) | 0.013 (4) | 0.001 (3) | 0.004 (4) |
C131 | 0.050 (6) | 0.064 (7) | 0.041 (6) | −0.004 (5) | 0.002 (5) | −0.008 (5) |
C14 | 0.019 (4) | 0.045 (5) | 0.020 (4) | 0.003 (3) | −0.002 (3) | −0.006 (3) |
C15 | 0.028 (4) | 0.029 (4) | 0.035 (5) | 0.006 (3) | −0.003 (3) | 0.002 (3) |
C16 | 0.025 (4) | 0.030 (4) | 0.031 (4) | 0.010 (3) | 0.011 (3) | 0.011 (3) |
N21 | 0.027 (3) | 0.024 (3) | 0.022 (3) | 0.010 (3) | 0.002 (3) | 0.002 (3) |
C22 | 0.028 (4) | 0.031 (4) | 0.027 (4) | 0.013 (3) | 0.007 (3) | 0.007 (3) |
C23 | 0.037 (5) | 0.033 (5) | 0.038 (5) | 0.018 (4) | −0.003 (4) | 0.001 (4) |
C231 | 0.067 (7) | 0.043 (6) | 0.055 (6) | 0.033 (5) | 0.008 (5) | 0.023 (5) |
C24 | 0.039 (5) | 0.038 (5) | 0.049 (6) | 0.023 (4) | 0.003 (4) | 0.001 (4) |
C25 | 0.035 (5) | 0.051 (6) | 0.043 (5) | 0.025 (4) | 0.014 (4) | 0.008 (4) |
C26 | 0.029 (4) | 0.034 (4) | 0.031 (4) | 0.012 (3) | 0.008 (3) | 0.008 (3) |
C1 | 0.058 (7) | 0.052 (6) | 0.059 (7) | 0.016 (5) | 0.002 (5) | 0.015 (5) |
Cl11 | 0.186 (5) | 0.070 (2) | 0.090 (3) | 0.052 (3) | 0.002 (3) | 0.009 (2) |
Cl12 | 0.077 (3) | 0.123 (4) | 0.098 (3) | 0.007 (2) | 0.028 (2) | 0.030 (3) |
Cl13 | 0.064 (2) | 0.084 (3) | 0.122 (4) | −0.0043 (19) | 0.003 (2) | −0.013 (2) |
C2 | 0.043 (6) | 0.050 (6) | 0.053 (6) | 0.018 (5) | 0.006 (5) | 0.010 (5) |
Cl21 | 0.058 (2) | 0.114 (3) | 0.072 (2) | −0.0119 (19) | −0.0015 (17) | 0.014 (2) |
Cl22 | 0.065 (2) | 0.091 (2) | 0.079 (2) | 0.0296 (18) | −0.0071 (16) | 0.0325 (19) |
Cl23 | 0.065 (2) | 0.125 (3) | 0.092 (3) | 0.024 (2) | 0.0131 (18) | 0.068 (3) |
Br1 | 0.0433 (5) | 0.0395 (5) | 0.0363 (5) | 0.0135 (4) | 0.0107 (4) | 0.0144 (4) |
Si1—H1 | 1.401 (10) | N21—C26 | 1.363 (10) |
Si1—N21 | 1.966 (6) | C22—C23 | 1.388 (11) |
Si1—N21i | 1.966 (6) | C22—H22 | 0.9500 |
Si1—N11i | 1.990 (7) | C23—C24 | 1.393 (13) |
Si1—N11 | 1.990 (7) | C23—C231 | 1.505 (12) |
Si1—H1 | 1.401 (10) | C231—H23A | 0.9800 |
N11—C12 | 1.349 (10) | C231—H23B | 0.9800 |
N11—C16 | 1.363 (10) | C231—H23C | 0.9800 |
C12—C13 | 1.396 (12) | C24—C25 | 1.389 (13) |
C12—H12 | 0.9500 | C24—H24 | 0.9500 |
C13—C14 | 1.435 (12) | C25—C26 | 1.371 (12) |
C13—C131 | 1.478 (14) | C25—H25 | 0.9500 |
C131—H13A | 0.9800 | C26—H26 | 0.9500 |
C131—H13B | 0.9800 | C1—Cl13 | 1.729 (12) |
C131—H13C | 0.9800 | C1—Cl11 | 1.752 (12) |
C14—C15 | 1.354 (12) | C1—Cl12 | 1.769 (12) |
C14—H14 | 0.9500 | C1—H11 | 1.0000 |
C15—C16 | 1.378 (12) | C2—Cl22 | 1.743 (11) |
C15—H15 | 0.9500 | C2—Cl23 | 1.758 (11) |
C16—H16 | 0.9500 | C2—Cl21 | 1.760 (11) |
N21—C22 | 1.353 (10) | C2—H21 | 1.0000 |
H1—Si1—N21 | 90 (3) | C15—C16—H16 | 119.2 |
H1—Si1—N21i | 90 (3) | C22—N21—C26 | 118.3 (7) |
N21—Si1—N21i | 179.999 (1) | C22—N21—Si1 | 120.6 (5) |
H1—Si1—N11i | 88 (3) | C26—N21—Si1 | 121.1 (5) |
N21—Si1—N11i | 90.2 (3) | N21—C22—C23 | 123.3 (7) |
N21i—Si1—N11i | 89.8 (3) | N21—C22—H22 | 118.4 |
H1—Si1—N11 | 92 (3) | C23—C22—H22 | 118.4 |
N21—Si1—N11 | 89.8 (3) | C22—C23—C24 | 117.6 (8) |
N21i—Si1—N11 | 90.2 (3) | C22—C23—C231 | 120.6 (8) |
N11i—Si1—N11 | 179.999 (1) | C24—C23—C231 | 121.8 (8) |
H1—Si1—H1 | 0 (3) | C23—C231—H23A | 109.5 |
N21—Si1—H1 | 90 (3) | C23—C231—H23B | 109.5 |
N21i—Si1—H1 | 90 (3) | H23A—C231—H23B | 109.5 |
N11i—Si1—H1 | 88 (3) | C23—C231—H23C | 109.5 |
N11—Si1—H1 | 92 (3) | H23A—C231—H23C | 109.5 |
C12—N11—C16 | 119.6 (7) | H23B—C231—H23C | 109.5 |
C12—N11—Si1 | 120.1 (5) | C25—C24—C23 | 119.4 (8) |
C16—N11—Si1 | 120.3 (5) | C25—C24—H24 | 120.3 |
N11—C12—C13 | 122.0 (8) | C23—C24—H24 | 120.3 |
N11—C12—H12 | 119.0 | C26—C25—C24 | 120.2 (8) |
C13—C12—H12 | 119.0 | C26—C25—H25 | 119.9 |
C12—C13—C14 | 116.8 (8) | C24—C25—H25 | 119.9 |
C12—C13—C131 | 120.6 (8) | N21—C26—C25 | 121.2 (8) |
C14—C13—C131 | 122.6 (8) | N21—C26—H26 | 119.4 |
C13—C131—H13A | 109.5 | C25—C26—H26 | 119.4 |
C13—C131—H13B | 109.5 | Cl13—C1—Cl11 | 109.6 (7) |
H13A—C131—H13B | 109.5 | Cl13—C1—Cl12 | 110.7 (7) |
C13—C131—H13C | 109.5 | Cl11—C1—Cl12 | 111.5 (7) |
H13A—C131—H13C | 109.5 | Cl13—C1—H11 | 108.3 |
H13B—C131—H13C | 109.5 | Cl11—C1—H11 | 108.3 |
C15—C14—C13 | 120.4 (8) | Cl12—C1—H11 | 108.3 |
C15—C14—H14 | 119.8 | Cl22—C2—Cl23 | 110.7 (6) |
C13—C14—H14 | 119.8 | Cl22—C2—Cl21 | 109.7 (6) |
C14—C15—C16 | 119.7 (8) | Cl23—C2—Cl21 | 110.6 (6) |
C14—C15—H15 | 120.2 | Cl22—C2—H21 | 108.6 |
C16—C15—H15 | 120.2 | Cl23—C2—H21 | 108.6 |
N11—C16—C15 | 121.6 (7) | Cl21—C2—H21 | 108.6 |
N11—C16—H16 | 119.2 | ||
H1—Si1—N11—C12 | −177 (3) | H1—Si1—N21—C22 | 178 (3) |
N21—Si1—N11—C12 | −86.8 (6) | N11i—Si1—N21—C22 | −94.4 (6) |
N21i—Si1—N11—C12 | 93.2 (6) | N11—Si1—N21—C22 | 85.6 (6) |
H1—Si1—N11—C16 | 2 (3) | H1—Si1—N21—C26 | −1 (3) |
N21—Si1—N11—C16 | 92.5 (6) | N11i—Si1—N21—C26 | 86.5 (6) |
N21i—Si1—N11—C16 | −87.5 (6) | N11—Si1—N21—C26 | −93.5 (6) |
C16—N11—C12—C13 | 1.0 (12) | C26—N21—C22—C23 | −0.2 (12) |
Si1—N11—C12—C13 | −179.7 (6) | Si1—N21—C22—C23 | −179.4 (7) |
N11—C12—C13—C14 | −0.2 (12) | N21—C22—C23—C24 | −0.5 (13) |
N11—C12—C13—C131 | −180.0 (9) | N21—C22—C23—C231 | 179.6 (8) |
C12—C13—C14—C15 | −1.0 (13) | C22—C23—C24—C25 | 0.4 (14) |
C131—C13—C14—C15 | 178.8 (9) | C231—C23—C24—C25 | −179.7 (9) |
C13—C14—C15—C16 | 1.3 (13) | C23—C24—C25—C26 | 0.5 (15) |
C12—N11—C16—C15 | −0.7 (11) | C22—N21—C26—C25 | 1.1 (12) |
Si1—N11—C16—C15 | −180.0 (6) | Si1—N21—C26—C25 | −179.7 (7) |
C14—C15—C16—N11 | −0.5 (12) | C24—C25—C26—N21 | −1.3 (14) |
Symmetry code: (i) −x, −y+1, −z. |
D—H···A | D—H | H···A | D···A | D—H···A |
C1—H11···Br1ii | 1.00 | 2.58 | 3.565 (12) | 170 |
C2—H21···Br1iii | 1.00 | 2.52 | 3.519 (11) | 174 |
Symmetry codes: (ii) −x+1, −y+1, −z; (iii) x, y−1, z+1. |
Experimental details
Crystal data | |
Chemical formula | C28H34Br2Cl12N4Si |
Mr | 1039.90 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 173 |
a, b, c (Å) | 8.840 (1), 10.059 (1), 13.330 (1) |
α, β, γ (°) | 97.65 (1), 90.68 (1), 108.63 (1) |
V (Å3) | 1111.35 (19) |
Z | 1 |
Radiation type | Mo Kα |
µ (mm−1) | 2.60 |
Crystal size (mm) | 0.40 × 0.35 × 0.20 |
Data collection | |
Diffractometer | Siemens CCD three-circle diffractometer |
Absorption correction | Empirical (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.37, 0.60 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 22862, 5095, 3406 |
Rint | 0.087 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.093, 0.268, 1.11 |
No. of reflections | 5095 |
No. of parameters | 219 |
No. of restraints | 1 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
w = 1/[σ2(Fo2) + (0.0856P)2 + 12.6187P] where P = (Fo2 + 2Fc2)/3 | |
Δρmax, Δρmin (e Å−3) | 2.39, −0.85 |
Computer programs: SMART (Siemens, 1995), SMART, SAINT (Siemens, 1995), SHELXS97 (Sheldrick, 1990), SHELXL97 (Sheldrick, 1997), XP in SHELXTL-Plus (Sheldrick, 1991).
D—H···A | D—H | H···A | D···A | D—H···A |
C1—H11···Br1i | 1.00 | 2.58 | 3.565 (12) | 169.9 |
C2—H21···Br1ii | 1.00 | 2.52 | 3.519 (11) | 173.9 |
Symmetry codes: (i) −x+1, −y+1, −z; (ii) x, y−1, z+1. |
Lewis acid–base complexes between silicon compounds and nitrogen bases have in recent years been the subject of many structural studies (Hensen et al., 1997, 1988; Chuit et al. 1993). Apart from [H2Si(3-picoline)4]2+.2Cl-.4CHCl3 (Fleischer et al., 1996), [H2Si(pyridine)4]2+.2Cl-.4CHCl3 (Hensen et al., 1998), [H2Si(3,4-lutidine)4]2+.2Cl-.6CHCl3 (Hensen et al., 2000), [H2Si(3,5-lutidine)4]2+.2Br-.2CH3CN (Bolte et al., 2000), [H2Si(4-picoline)4]2+.2Cl-.6CHCl3 (Stumpf & Bolte, 2001) and [H2Si(4-picoline)4]2+.2Br-.6CHCl3 (Bolte & Faber, 2001), the crystal structure of the title compound, (I), is a further example with the structural element H2Si(pyridine)4.
The coordination of the Si atom can be described as a slightly distorted octahedron, with the 3-picoline ligands in the equatorial plane and the two H atoms occupying axial positions. The two Br- ions are displaced from the first sphere of coordination. It is remarkable that (I) is not isomorphous with its analogue in which the Br- ions are substituted by Cl- ions (Fleischer et al., 1996). A least-squares fit of all non-H atoms of the cations of both structures (r.m.s. deviation 0.259 Å) shows that there are only minor differences between them, e.g. the angle between the aromatic rings is 90.0 (3)° in (I) and 96.9° in the structure containing the Cl- ions. However, the packing patterns of the two structures are completely different.