organic compounds
of benzyl(methyl)phenyl[(piperidin-1-ium-1-yl)methyl]silane bromide
aFakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, 44227 Dortmund, Germany
*Correspondence e-mail: carsten.strohmann@tu-dortmund.de
The title compound, C20H29NSi+·Br−, contains a chiral silicon atom but crystallizes as a racemate. The C—Si—C bond angles in the range of 103.64 (8)–111.59 (9)° are usual for tetrahedral geometry. The piperidine ring shows a regular chair conformation with an equatorially positioned exocyclic N—C bond. In the crystal, there is a hydrogen bond between the ammonium cation and the bromide anion. The crystal packing shows the dominant intermolecular interaction to be the electrostatic attraction between the ammonium cation and the bromide anion.
Keywords: crystal structure; chiral organosilane; N—H⋯Br hydrogen bond.
CCDC reference: 1423495
1. Related literature
Benzylmethyl(piperidinomethyl)silane and its methyliodide salt are used as model systems to investigate the stereochemistry of substitution reactions with silyllithium compounds as nucleophiles, see: Strohmann et al. (2004).
2. Experimental
2.1. Crystal data
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2.3. Refinement
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Data collection: APEX2 (Bruker, 2003); cell SAINT (Bruker, 2003); data reduction: SAINT; program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009) and publCIF (Westrip, 2010).
Supporting information
CCDC reference: 1423495
10.1107/S2056989015016965/sj5471sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S2056989015016965/sj5471Isup2.hkl
Supporting information file. DOI: 10.1107/S2056989015016965/sj5471Isup3.cml
The title compound was synthesized to increase the enantiomeric ratio of the chiral benzylmethylphenyl(piperidinomethyl)silane. Therefore the silane was treated with 1 eq of HBr in Et2O (1 M). Solvent was evaporated in vacuum, and the solid residue was recrystallized from isopropanol at 243 K for 24 h. The crystals were washed with cold isopropanol to prepare them for X-ray analysis.
Data collection: APEX2 (Bruker, 2003); cell
SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009) and publCIF (Westrip, 2010).C20H28NSi+·Br− | F(000) = 816 |
Mr = 390.43 | Dx = 1.313 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
a = 13.9311 (12) Å | Cell parameters from 7370 reflections |
b = 7.4605 (6) Å | θ = 2.9–27.9° |
c = 19.3515 (17) Å | µ = 2.14 mm−1 |
β = 100.926 (2)° | T = 173 K |
V = 1974.8 (3) Å3 | Block, colourless |
Z = 4 | 0.2 × 0.2 × 0.1 mm |
Bruker APEXII CCD diffractometer | 3948 reflections with I > 2σ(I) |
φ and ω scans | Rint = 0.040 |
Absorption correction: multi-scan (SADABS, Bruker, 2015) | θmax = 28.0°, θmin = 2.1° |
Tmin = 0.421, Tmax = 0.746 | h = −18→18 |
26749 measured reflections | k = −9→9 |
4759 independent reflections | l = −25→25 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.031 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.080 | w = 1/[σ2(Fo2) + (0.0462P)2 + 0.3152P] where P = (Fo2 + 2Fc2)/3 |
S = 1.02 | (Δ/σ)max = 0.001 |
4759 reflections | Δρmax = 0.66 e Å−3 |
213 parameters | Δρmin = −0.25 e Å−3 |
0 restraints |
C20H28NSi+·Br− | V = 1974.8 (3) Å3 |
Mr = 390.43 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 13.9311 (12) Å | µ = 2.14 mm−1 |
b = 7.4605 (6) Å | T = 173 K |
c = 19.3515 (17) Å | 0.2 × 0.2 × 0.1 mm |
β = 100.926 (2)° |
Bruker APEXII CCD diffractometer | 4759 independent reflections |
Absorption correction: multi-scan (SADABS, Bruker, 2015) | 3948 reflections with I > 2σ(I) |
Tmin = 0.421, Tmax = 0.746 | Rint = 0.040 |
26749 measured reflections |
R[F2 > 2σ(F2)] = 0.031 | 0 restraints |
wR(F2) = 0.080 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | Δρmax = 0.66 e Å−3 |
4759 reflections | Δρmin = −0.25 e Å−3 |
213 parameters |
Experimental. Absorption correction: SADABS-2014/5 (Bruker,2014/5) was used for absorption correction. wR2(int) was 0.1354 before and 0.0450 after correction. The Ratio of minimum to maximum transmission is 0.5649. The λ/2 correction factor is 0.00150. |
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. 1. Fixed Uiso At 1.2 times of: All C(H) groups, All C(H,H) groups At 1.5 times of: All C(H,H,H) groups 2.a Secondary CH2 refined with riding coordinates: C2(H2A,H2B), C15(H15A,H15B), C16(H16A,H16B), C17(H17A,H17B), C18(H18A,H18B), C19(H19A,H19B), C20(H20A,H20B) 2.b Aromatic/amide H refined with riding coordinates: C4(H4), C5(H5), C6(H6), C7(H7), C8(H8), C10(H10), C11(H11), C12(H12), C13(H13), C14(H14) 2.c Idealized Me refined as rotating group: C1(H1A,H1B,H1C) |
x | y | z | Uiso*/Ueq | ||
Si1 | 0.27017 (3) | 0.16579 (6) | 0.40241 (2) | 0.02506 (11) | |
N1 | 0.47332 (10) | 0.2487 (2) | 0.38731 (7) | 0.0226 (3) | |
H1 | 0.4648 (13) | 0.358 (3) | 0.3882 (9) | 0.026 (5)* | |
C1 | 0.22693 (15) | −0.0080 (3) | 0.33465 (11) | 0.0397 (5) | |
H1A | 0.2388 | 0.0327 | 0.2889 | 0.060* | |
H1B | 0.1568 | −0.0282 | 0.3317 | 0.060* | |
H1C | 0.2624 | −0.1202 | 0.3477 | 0.060* | |
C2 | 0.22659 (14) | 0.3967 (3) | 0.37105 (10) | 0.0332 (4) | |
H2A | 0.2580 | 0.4872 | 0.4055 | 0.040* | |
H2B | 0.2463 | 0.4217 | 0.3255 | 0.040* | |
C3 | 0.11714 (13) | 0.4124 (2) | 0.36237 (9) | 0.0287 (4) | |
C4 | 0.05486 (15) | 0.3325 (2) | 0.30609 (11) | 0.0365 (4) | |
H4 | 0.0816 | 0.2690 | 0.2716 | 0.044* | |
C5 | −0.04527 (17) | 0.3443 (3) | 0.29963 (13) | 0.0494 (6) | |
H5 | −0.0867 | 0.2876 | 0.2612 | 0.059* | |
C6 | −0.08555 (16) | 0.4373 (3) | 0.34831 (14) | 0.0533 (6) | |
H6 | −0.1546 | 0.4453 | 0.3435 | 0.064* | |
C7 | −0.02525 (17) | 0.5190 (3) | 0.40435 (12) | 0.0499 (6) | |
H7 | −0.0528 | 0.5845 | 0.4379 | 0.060* | |
C8 | 0.07535 (15) | 0.5058 (3) | 0.41163 (10) | 0.0376 (4) | |
H8 | 0.1163 | 0.5609 | 0.4507 | 0.045* | |
C9 | 0.22505 (12) | 0.1129 (2) | 0.48553 (9) | 0.0274 (4) | |
C10 | 0.15034 (14) | −0.0107 (3) | 0.48712 (11) | 0.0375 (4) | |
H10 | 0.1224 | −0.0726 | 0.4452 | 0.045* | |
C11 | 0.11604 (16) | −0.0451 (3) | 0.54855 (12) | 0.0463 (5) | |
H11 | 0.0652 | −0.1301 | 0.5482 | 0.056* | |
C12 | 0.15485 (16) | 0.0426 (3) | 0.60973 (11) | 0.0466 (5) | |
H12 | 0.1311 | 0.0186 | 0.6517 | 0.056* | |
C13 | 0.22922 (17) | 0.1669 (3) | 0.60999 (11) | 0.0423 (5) | |
H13 | 0.2564 | 0.2284 | 0.6521 | 0.051* | |
C14 | 0.26369 (15) | 0.2009 (3) | 0.54857 (10) | 0.0339 (4) | |
H14 | 0.3147 | 0.2859 | 0.5493 | 0.041* | |
C15 | 0.40836 (12) | 0.1599 (2) | 0.43050 (9) | 0.0250 (3) | |
H15A | 0.4242 | 0.2126 | 0.4783 | 0.030* | |
H15B | 0.4278 | 0.0322 | 0.4352 | 0.030* | |
C16 | 0.57838 (13) | 0.2155 (3) | 0.41985 (9) | 0.0296 (4) | |
H16A | 0.5913 | 0.0849 | 0.4209 | 0.036* | |
H16B | 0.5911 | 0.2596 | 0.4690 | 0.036* | |
C17 | 0.64701 (14) | 0.3085 (3) | 0.37913 (10) | 0.0351 (4) | |
H17A | 0.7155 | 0.2796 | 0.4007 | 0.042* | |
H17B | 0.6385 | 0.4399 | 0.3818 | 0.042* | |
C18 | 0.62716 (14) | 0.2504 (3) | 0.30259 (10) | 0.0369 (4) | |
H18A | 0.6428 | 0.1216 | 0.2994 | 0.044* | |
H18B | 0.6695 | 0.3190 | 0.2764 | 0.044* | |
C19 | 0.52035 (14) | 0.2826 (3) | 0.26998 (9) | 0.0319 (4) | |
H19A | 0.5070 | 0.4130 | 0.2682 | 0.038* | |
H19B | 0.5071 | 0.2364 | 0.2211 | 0.038* | |
C20 | 0.45269 (13) | 0.1907 (2) | 0.31190 (9) | 0.0276 (4) | |
H20A | 0.3840 | 0.2195 | 0.2908 | 0.033* | |
H20B | 0.4611 | 0.0592 | 0.3094 | 0.033* | |
Br1 | 0.45737 (2) | 0.67990 (2) | 0.38635 (2) | 0.03319 (7) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Si1 | 0.0243 (2) | 0.0241 (2) | 0.0264 (2) | 0.00079 (18) | 0.00388 (18) | −0.00076 (18) |
N1 | 0.0252 (8) | 0.0172 (6) | 0.0254 (7) | 0.0034 (5) | 0.0050 (6) | −0.0016 (5) |
C1 | 0.0374 (11) | 0.0395 (11) | 0.0399 (10) | −0.0018 (9) | 0.0013 (8) | −0.0105 (9) |
C2 | 0.0316 (10) | 0.0306 (9) | 0.0383 (10) | 0.0021 (8) | 0.0090 (8) | 0.0082 (8) |
C3 | 0.0312 (10) | 0.0260 (8) | 0.0294 (9) | 0.0031 (7) | 0.0072 (7) | 0.0102 (7) |
C4 | 0.0406 (11) | 0.0298 (10) | 0.0364 (10) | 0.0061 (8) | −0.0001 (8) | 0.0057 (8) |
C5 | 0.0436 (13) | 0.0386 (12) | 0.0582 (14) | −0.0035 (9) | −0.0100 (11) | 0.0160 (10) |
C6 | 0.0292 (11) | 0.0587 (14) | 0.0730 (16) | 0.0058 (10) | 0.0125 (11) | 0.0356 (13) |
C7 | 0.0494 (13) | 0.0592 (14) | 0.0475 (12) | 0.0228 (11) | 0.0256 (11) | 0.0215 (11) |
C8 | 0.0427 (11) | 0.0385 (10) | 0.0316 (9) | 0.0089 (9) | 0.0068 (8) | 0.0074 (8) |
C9 | 0.0250 (9) | 0.0249 (8) | 0.0323 (9) | 0.0042 (7) | 0.0058 (7) | 0.0044 (7) |
C10 | 0.0333 (10) | 0.0359 (10) | 0.0420 (10) | −0.0051 (8) | 0.0037 (8) | 0.0071 (8) |
C11 | 0.0355 (11) | 0.0475 (12) | 0.0578 (14) | −0.0038 (9) | 0.0137 (10) | 0.0193 (10) |
C12 | 0.0447 (12) | 0.0572 (13) | 0.0427 (12) | 0.0113 (10) | 0.0200 (10) | 0.0164 (10) |
C13 | 0.0456 (12) | 0.0479 (13) | 0.0355 (10) | 0.0088 (9) | 0.0130 (9) | −0.0018 (9) |
C14 | 0.0339 (10) | 0.0333 (10) | 0.0361 (10) | 0.0014 (8) | 0.0110 (8) | −0.0032 (8) |
C15 | 0.0254 (9) | 0.0248 (8) | 0.0251 (8) | 0.0012 (6) | 0.0052 (6) | 0.0018 (6) |
C16 | 0.0243 (9) | 0.0356 (9) | 0.0280 (9) | 0.0052 (7) | 0.0028 (7) | −0.0006 (7) |
C17 | 0.0246 (9) | 0.0437 (11) | 0.0375 (10) | 0.0002 (8) | 0.0075 (8) | −0.0023 (8) |
C18 | 0.0331 (11) | 0.0444 (11) | 0.0362 (10) | 0.0042 (9) | 0.0144 (8) | −0.0007 (9) |
C19 | 0.0365 (10) | 0.0340 (9) | 0.0264 (8) | 0.0038 (8) | 0.0091 (7) | 0.0000 (7) |
C20 | 0.0302 (9) | 0.0286 (9) | 0.0234 (8) | 0.0022 (7) | 0.0035 (7) | −0.0030 (7) |
Br1 | 0.04173 (13) | 0.02011 (10) | 0.03668 (11) | 0.00323 (7) | 0.00476 (8) | −0.00210 (7) |
Si1—C1 | 1.8614 (19) | C9—C14 | 1.400 (3) |
Si1—C2 | 1.8883 (19) | C10—H10 | 0.9500 |
Si1—C9 | 1.8766 (18) | C10—C11 | 1.387 (3) |
Si1—C15 | 1.8991 (18) | C11—H11 | 0.9500 |
N1—H1 | 0.82 (2) | C11—C12 | 1.371 (3) |
N1—C15 | 1.498 (2) | C12—H12 | 0.9500 |
N1—C16 | 1.500 (2) | C12—C13 | 1.389 (3) |
N1—C20 | 1.497 (2) | C13—H13 | 0.9500 |
C1—H1A | 0.9800 | C13—C14 | 1.387 (3) |
C1—H1B | 0.9800 | C14—H14 | 0.9500 |
C1—H1C | 0.9800 | C15—H15A | 0.9900 |
C2—H2A | 0.9900 | C15—H15B | 0.9900 |
C2—H2B | 0.9900 | C16—H16A | 0.9900 |
C2—C3 | 1.506 (3) | C16—H16B | 0.9900 |
C3—C4 | 1.391 (3) | C16—C17 | 1.518 (3) |
C3—C8 | 1.394 (3) | C17—H17A | 0.9900 |
C4—H4 | 0.9500 | C17—H17B | 0.9900 |
C4—C5 | 1.379 (3) | C17—C18 | 1.518 (3) |
C5—H5 | 0.9500 | C18—H18A | 0.9900 |
C5—C6 | 1.373 (4) | C18—H18B | 0.9900 |
C6—H6 | 0.9500 | C18—C19 | 1.521 (3) |
C6—C7 | 1.382 (4) | C19—H19A | 0.9900 |
C7—H7 | 0.9500 | C19—H19B | 0.9900 |
C7—C8 | 1.385 (3) | C19—C20 | 1.519 (3) |
C8—H8 | 0.9500 | C20—H20A | 0.9900 |
C9—C10 | 1.395 (3) | C20—H20B | 0.9900 |
C1—Si1—C2 | 111.59 (9) | C10—C11—H11 | 119.7 |
C1—Si1—C9 | 109.93 (9) | C12—C11—C10 | 120.6 (2) |
C1—Si1—C15 | 111.14 (8) | C12—C11—H11 | 119.7 |
C2—Si1—C15 | 111.09 (8) | C11—C12—H12 | 120.2 |
C9—Si1—C2 | 109.14 (8) | C11—C12—C13 | 119.55 (19) |
C9—Si1—C15 | 103.64 (8) | C13—C12—H12 | 120.2 |
C15—N1—H1 | 108.7 (13) | C12—C13—H13 | 120.1 |
C15—N1—C16 | 109.70 (13) | C14—C13—C12 | 119.9 (2) |
C16—N1—H1 | 106.7 (13) | C14—C13—H13 | 120.1 |
C20—N1—H1 | 107.8 (12) | C9—C14—H14 | 119.3 |
C20—N1—C15 | 113.03 (13) | C13—C14—C9 | 121.48 (19) |
C20—N1—C16 | 110.67 (13) | C13—C14—H14 | 119.3 |
Si1—C1—H1A | 109.5 | Si1—C15—H15A | 107.0 |
Si1—C1—H1B | 109.5 | Si1—C15—H15B | 107.0 |
Si1—C1—H1C | 109.5 | N1—C15—Si1 | 121.12 (11) |
H1A—C1—H1B | 109.5 | N1—C15—H15A | 107.0 |
H1A—C1—H1C | 109.5 | N1—C15—H15B | 107.0 |
H1B—C1—H1C | 109.5 | H15A—C15—H15B | 106.8 |
Si1—C2—H2A | 109.4 | N1—C16—H16A | 109.3 |
Si1—C2—H2B | 109.4 | N1—C16—H16B | 109.3 |
H2A—C2—H2B | 108.0 | N1—C16—C17 | 111.52 (14) |
C3—C2—Si1 | 111.32 (12) | H16A—C16—H16B | 108.0 |
C3—C2—H2A | 109.4 | C17—C16—H16A | 109.3 |
C3—C2—H2B | 109.4 | C17—C16—H16B | 109.3 |
C4—C3—C2 | 121.46 (17) | C16—C17—H17A | 109.4 |
C4—C3—C8 | 118.03 (18) | C16—C17—H17B | 109.4 |
C8—C3—C2 | 120.50 (17) | C16—C17—C18 | 111.09 (16) |
C3—C4—H4 | 119.5 | H17A—C17—H17B | 108.0 |
C5—C4—C3 | 120.9 (2) | C18—C17—H17A | 109.4 |
C5—C4—H4 | 119.5 | C18—C17—H17B | 109.4 |
C4—C5—H5 | 119.7 | C17—C18—H18A | 109.7 |
C6—C5—C4 | 120.5 (2) | C17—C18—H18B | 109.7 |
C6—C5—H5 | 119.7 | C17—C18—C19 | 110.05 (15) |
C5—C6—H6 | 120.2 | H18A—C18—H18B | 108.2 |
C5—C6—C7 | 119.7 (2) | C19—C18—H18A | 109.7 |
C7—C6—H6 | 120.2 | C19—C18—H18B | 109.7 |
C6—C7—H7 | 120.0 | C18—C19—H19A | 109.4 |
C6—C7—C8 | 120.1 (2) | C18—C19—H19B | 109.4 |
C8—C7—H7 | 120.0 | H19A—C19—H19B | 108.0 |
C3—C8—H8 | 119.6 | C20—C19—C18 | 111.38 (15) |
C7—C8—C3 | 120.8 (2) | C20—C19—H19A | 109.4 |
C7—C8—H8 | 119.6 | C20—C19—H19B | 109.4 |
C10—C9—Si1 | 122.04 (14) | N1—C20—C19 | 111.48 (14) |
C10—C9—C14 | 117.13 (17) | N1—C20—H20A | 109.3 |
C14—C9—Si1 | 120.80 (14) | N1—C20—H20B | 109.3 |
C9—C10—H10 | 119.3 | C19—C20—H20A | 109.3 |
C11—C10—C9 | 121.40 (19) | C19—C20—H20B | 109.3 |
C11—C10—H10 | 119.3 | H20A—C20—H20B | 108.0 |
Si1—C2—C3—C4 | −74.37 (19) | C9—Si1—C2—C3 | −55.09 (15) |
Si1—C2—C3—C8 | 104.58 (17) | C9—Si1—C15—N1 | −160.77 (12) |
Si1—C9—C10—C11 | −178.33 (15) | C9—C10—C11—C12 | 0.2 (3) |
Si1—C9—C14—C13 | 178.18 (15) | C10—C9—C14—C13 | 0.0 (3) |
N1—C16—C17—C18 | −56.7 (2) | C10—C11—C12—C13 | 0.0 (3) |
C1—Si1—C2—C3 | 66.61 (15) | C11—C12—C13—C14 | −0.1 (3) |
C1—Si1—C9—C10 | −15.24 (18) | C12—C13—C14—C9 | 0.2 (3) |
C1—Si1—C9—C14 | 166.66 (15) | C14—C9—C10—C11 | −0.2 (3) |
C1—Si1—C15—N1 | 81.20 (15) | C15—Si1—C2—C3 | −168.75 (12) |
C2—Si1—C9—C10 | 107.45 (16) | C15—Si1—C9—C10 | −134.11 (15) |
C2—Si1—C9—C14 | −70.65 (16) | C15—Si1—C9—C14 | 47.79 (16) |
C2—Si1—C15—N1 | −43.69 (15) | C15—N1—C16—C17 | −178.06 (14) |
C2—C3—C4—C5 | 178.46 (17) | C15—N1—C20—C19 | −179.63 (14) |
C2—C3—C8—C7 | −179.31 (17) | C16—N1—C15—Si1 | −177.28 (11) |
C3—C4—C5—C6 | 0.8 (3) | C16—N1—C20—C19 | −56.13 (18) |
C4—C3—C8—C7 | −0.3 (3) | C16—C17—C18—C19 | 55.3 (2) |
C4—C5—C6—C7 | −0.3 (3) | C17—C18—C19—C20 | −55.1 (2) |
C5—C6—C7—C8 | −0.6 (3) | C18—C19—C20—N1 | 56.0 (2) |
C6—C7—C8—C3 | 0.9 (3) | C20—N1—C15—Si1 | −53.24 (17) |
C8—C3—C4—C5 | −0.5 (3) | C20—N1—C16—C17 | 56.54 (19) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···Br1 | 0.82 (2) | 2.41 (2) | 3.2242 (15) | 173.4 (17) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···Br1 | 0.82 (2) | 2.41 (2) | 3.2242 (15) | 173.4 (17) |
Acknowledgements
We are grateful to the Deutsche Forschungsgemeinschaft (DFG) for financial support.
References
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