organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

Crystal structure of benz­yl(meth­yl)phen­yl[(piperidin-1-ium-1-yl)meth­yl]silane bromide

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aFakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, 44227 Dortmund, Germany
*Correspondence e-mail: carsten.strohmann@tu-dortmund.de

Edited by J. Simpson, University of Otago, New Zealand (Received 29 August 2015; accepted 10 September 2015; online 17 September 2015)

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.

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[Strohmann, C., Bindl, M., Fraass, V. C. & Hörnig, J. (2004). Angew. Chem. Int. Ed. 43, 1011-1014.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C20H28NSi+·Br

  • Mr = 390.43

  • Monoclinic, P 21 /n

  • a = 13.9311 (12) Å

  • b = 7.4605 (6) Å

  • c = 19.3515 (17) Å

  • β = 100.926 (2)°

  • V = 1974.8 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 2.14 mm−1

  • T = 173 K

  • 0.2 × 0.2 × 0.1 mm

2.2. Data collection

  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS, Bruker, 2015[Bruker (2015). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.421, Tmax = 0.746

  • 26749 measured reflections

  • 4759 independent reflections

  • 3948 reflections with I > 2σ(I)

  • Rint = 0.040

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.031

  • wR(F2) = 0.080

  • S = 1.02

  • 4759 reflections

  • 213 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.66 e Å−3

  • Δρmin = −0.25 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯Br1 0.82 (2) 2.41 (2) 3.2242 (15) 173.4 (17)

Data collection: APEX2 (Bruker, 2003[Bruker (2003). APEX2 and SAINT . Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2003[Bruker (2003). APEX2 and SAINT . Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXT (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Synthesis and crystallization top

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.

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 1. Treatment of hydrogen atoms: Uiso(H) = 1.2 times Uiso(C) for CH and CH2, Uiso(H) = 1.5 times Uiso(C) for CH3; refinement: secondary CH2 and aromatic H with riding coordinates, CH3 as a rotating methyl group.

Related literature top

Preparation of the hydrobromide starting from benzylmethyl(piperidinomethyl)silane was used as a methyliodide-free alternative to determine the chirality of quarternary silicon centre. Benzylmethyl(piperidinomethyl)silane and its methyliodide salt is used as a model system to investigate the stereochemistry of substitution reactions with silyllithium compounds as nucleophiles (Strohmann et al., 2004).

Computing details top

Data collection: APEX2 (Bruker, 2003); cell refinement: 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).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound with anisotropic displacement ellipsoids drawn at the 50% probability level. An intermolecular hydrogen bond is shown as a dashed line.
[Figure 2] Fig. 2. Crystal packing of the title compound viewed along b axis. H-atoms are omitted for clarity.
Benzyl(methyl)phenyl[(piperidin-1-ium-1-yl)methyl]silane bromide top
Crystal data top
C20H28NSi+·BrF(000) = 816
Mr = 390.43Dx = 1.313 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
a = 13.9311 (12) ÅCell parameters from 7370 reflections
b = 7.4605 (6) Åθ = 2.9–27.9°
c = 19.3515 (17) ŵ = 2.14 mm1
β = 100.926 (2)°T = 173 K
V = 1974.8 (3) Å3Block, colourless
Z = 40.2 × 0.2 × 0.1 mm
Data collection top
Bruker APEXII CCD
diffractometer
3948 reflections with I > 2σ(I)
φ and ω scansRint = 0.040
Absorption correction: multi-scan
(SADABS, Bruker, 2015)
θmax = 28.0°, θmin = 2.1°
Tmin = 0.421, Tmax = 0.746h = 1818
26749 measured reflectionsk = 99
4759 independent reflectionsl = 2525
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.031H 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 reflectionsΔρmax = 0.66 e Å3
213 parametersΔρmin = 0.25 e Å3
0 restraints
Crystal data top
C20H28NSi+·BrV = 1974.8 (3) Å3
Mr = 390.43Z = 4
Monoclinic, P21/nMo Kα radiation
a = 13.9311 (12) ŵ = 2.14 mm1
b = 7.4605 (6) ÅT = 173 K
c = 19.3515 (17) Å0.2 × 0.2 × 0.1 mm
β = 100.926 (2)°
Data collection top
Bruker APEXII CCD
diffractometer
4759 independent reflections
Absorption correction: multi-scan
(SADABS, Bruker, 2015)
3948 reflections with I > 2σ(I)
Tmin = 0.421, Tmax = 0.746Rint = 0.040
26749 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0310 restraints
wR(F2) = 0.080H atoms treated by a mixture of independent and constrained refinement
S = 1.02Δρmax = 0.66 e Å3
4759 reflectionsΔρmin = 0.25 e Å3
213 parameters
Special details top

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)

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Si10.27017 (3)0.16579 (6)0.40241 (2)0.02506 (11)
N10.47332 (10)0.2487 (2)0.38731 (7)0.0226 (3)
H10.4648 (13)0.358 (3)0.3882 (9)0.026 (5)*
C10.22693 (15)0.0080 (3)0.33465 (11)0.0397 (5)
H1A0.23880.03270.28890.060*
H1B0.15680.02820.33170.060*
H1C0.26240.12020.34770.060*
C20.22659 (14)0.3967 (3)0.37105 (10)0.0332 (4)
H2A0.25800.48720.40550.040*
H2B0.24630.42170.32550.040*
C30.11714 (13)0.4124 (2)0.36237 (9)0.0287 (4)
C40.05486 (15)0.3325 (2)0.30609 (11)0.0365 (4)
H40.08160.26900.27160.044*
C50.04527 (17)0.3443 (3)0.29963 (13)0.0494 (6)
H50.08670.28760.26120.059*
C60.08555 (16)0.4373 (3)0.34831 (14)0.0533 (6)
H60.15460.44530.34350.064*
C70.02525 (17)0.5190 (3)0.40435 (12)0.0499 (6)
H70.05280.58450.43790.060*
C80.07535 (15)0.5058 (3)0.41163 (10)0.0376 (4)
H80.11630.56090.45070.045*
C90.22505 (12)0.1129 (2)0.48553 (9)0.0274 (4)
C100.15034 (14)0.0107 (3)0.48712 (11)0.0375 (4)
H100.12240.07260.44520.045*
C110.11604 (16)0.0451 (3)0.54855 (12)0.0463 (5)
H110.06520.13010.54820.056*
C120.15485 (16)0.0426 (3)0.60973 (11)0.0466 (5)
H120.13110.01860.65170.056*
C130.22922 (17)0.1669 (3)0.60999 (11)0.0423 (5)
H130.25640.22840.65210.051*
C140.26369 (15)0.2009 (3)0.54857 (10)0.0339 (4)
H140.31470.28590.54930.041*
C150.40836 (12)0.1599 (2)0.43050 (9)0.0250 (3)
H15A0.42420.21260.47830.030*
H15B0.42780.03220.43520.030*
C160.57838 (13)0.2155 (3)0.41985 (9)0.0296 (4)
H16A0.59130.08490.42090.036*
H16B0.59110.25960.46900.036*
C170.64701 (14)0.3085 (3)0.37913 (10)0.0351 (4)
H17A0.71550.27960.40070.042*
H17B0.63850.43990.38180.042*
C180.62716 (14)0.2504 (3)0.30259 (10)0.0369 (4)
H18A0.64280.12160.29940.044*
H18B0.66950.31900.27640.044*
C190.52035 (14)0.2826 (3)0.26998 (9)0.0319 (4)
H19A0.50700.41300.26820.038*
H19B0.50710.23640.22110.038*
C200.45269 (13)0.1907 (2)0.31190 (9)0.0276 (4)
H20A0.38400.21950.29080.033*
H20B0.46110.05920.30940.033*
Br10.45737 (2)0.67990 (2)0.38635 (2)0.03319 (7)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Si10.0243 (2)0.0241 (2)0.0264 (2)0.00079 (18)0.00388 (18)0.00076 (18)
N10.0252 (8)0.0172 (6)0.0254 (7)0.0034 (5)0.0050 (6)0.0016 (5)
C10.0374 (11)0.0395 (11)0.0399 (10)0.0018 (9)0.0013 (8)0.0105 (9)
C20.0316 (10)0.0306 (9)0.0383 (10)0.0021 (8)0.0090 (8)0.0082 (8)
C30.0312 (10)0.0260 (8)0.0294 (9)0.0031 (7)0.0072 (7)0.0102 (7)
C40.0406 (11)0.0298 (10)0.0364 (10)0.0061 (8)0.0001 (8)0.0057 (8)
C50.0436 (13)0.0386 (12)0.0582 (14)0.0035 (9)0.0100 (11)0.0160 (10)
C60.0292 (11)0.0587 (14)0.0730 (16)0.0058 (10)0.0125 (11)0.0356 (13)
C70.0494 (13)0.0592 (14)0.0475 (12)0.0228 (11)0.0256 (11)0.0215 (11)
C80.0427 (11)0.0385 (10)0.0316 (9)0.0089 (9)0.0068 (8)0.0074 (8)
C90.0250 (9)0.0249 (8)0.0323 (9)0.0042 (7)0.0058 (7)0.0044 (7)
C100.0333 (10)0.0359 (10)0.0420 (10)0.0051 (8)0.0037 (8)0.0071 (8)
C110.0355 (11)0.0475 (12)0.0578 (14)0.0038 (9)0.0137 (10)0.0193 (10)
C120.0447 (12)0.0572 (13)0.0427 (12)0.0113 (10)0.0200 (10)0.0164 (10)
C130.0456 (12)0.0479 (13)0.0355 (10)0.0088 (9)0.0130 (9)0.0018 (9)
C140.0339 (10)0.0333 (10)0.0361 (10)0.0014 (8)0.0110 (8)0.0032 (8)
C150.0254 (9)0.0248 (8)0.0251 (8)0.0012 (6)0.0052 (6)0.0018 (6)
C160.0243 (9)0.0356 (9)0.0280 (9)0.0052 (7)0.0028 (7)0.0006 (7)
C170.0246 (9)0.0437 (11)0.0375 (10)0.0002 (8)0.0075 (8)0.0023 (8)
C180.0331 (11)0.0444 (11)0.0362 (10)0.0042 (9)0.0144 (8)0.0007 (9)
C190.0365 (10)0.0340 (9)0.0264 (8)0.0038 (8)0.0091 (7)0.0000 (7)
C200.0302 (9)0.0286 (9)0.0234 (8)0.0022 (7)0.0035 (7)0.0030 (7)
Br10.04173 (13)0.02011 (10)0.03668 (11)0.00323 (7)0.00476 (8)0.00210 (7)
Geometric parameters (Å, º) top
Si1—C11.8614 (19)C9—C141.400 (3)
Si1—C21.8883 (19)C10—H100.9500
Si1—C91.8766 (18)C10—C111.387 (3)
Si1—C151.8991 (18)C11—H110.9500
N1—H10.82 (2)C11—C121.371 (3)
N1—C151.498 (2)C12—H120.9500
N1—C161.500 (2)C12—C131.389 (3)
N1—C201.497 (2)C13—H130.9500
C1—H1A0.9800C13—C141.387 (3)
C1—H1B0.9800C14—H140.9500
C1—H1C0.9800C15—H15A0.9900
C2—H2A0.9900C15—H15B0.9900
C2—H2B0.9900C16—H16A0.9900
C2—C31.506 (3)C16—H16B0.9900
C3—C41.391 (3)C16—C171.518 (3)
C3—C81.394 (3)C17—H17A0.9900
C4—H40.9500C17—H17B0.9900
C4—C51.379 (3)C17—C181.518 (3)
C5—H50.9500C18—H18A0.9900
C5—C61.373 (4)C18—H18B0.9900
C6—H60.9500C18—C191.521 (3)
C6—C71.382 (4)C19—H19A0.9900
C7—H70.9500C19—H19B0.9900
C7—C81.385 (3)C19—C201.519 (3)
C8—H80.9500C20—H20A0.9900
C9—C101.395 (3)C20—H20B0.9900
C1—Si1—C2111.59 (9)C10—C11—H11119.7
C1—Si1—C9109.93 (9)C12—C11—C10120.6 (2)
C1—Si1—C15111.14 (8)C12—C11—H11119.7
C2—Si1—C15111.09 (8)C11—C12—H12120.2
C9—Si1—C2109.14 (8)C11—C12—C13119.55 (19)
C9—Si1—C15103.64 (8)C13—C12—H12120.2
C15—N1—H1108.7 (13)C12—C13—H13120.1
C15—N1—C16109.70 (13)C14—C13—C12119.9 (2)
C16—N1—H1106.7 (13)C14—C13—H13120.1
C20—N1—H1107.8 (12)C9—C14—H14119.3
C20—N1—C15113.03 (13)C13—C14—C9121.48 (19)
C20—N1—C16110.67 (13)C13—C14—H14119.3
Si1—C1—H1A109.5Si1—C15—H15A107.0
Si1—C1—H1B109.5Si1—C15—H15B107.0
Si1—C1—H1C109.5N1—C15—Si1121.12 (11)
H1A—C1—H1B109.5N1—C15—H15A107.0
H1A—C1—H1C109.5N1—C15—H15B107.0
H1B—C1—H1C109.5H15A—C15—H15B106.8
Si1—C2—H2A109.4N1—C16—H16A109.3
Si1—C2—H2B109.4N1—C16—H16B109.3
H2A—C2—H2B108.0N1—C16—C17111.52 (14)
C3—C2—Si1111.32 (12)H16A—C16—H16B108.0
C3—C2—H2A109.4C17—C16—H16A109.3
C3—C2—H2B109.4C17—C16—H16B109.3
C4—C3—C2121.46 (17)C16—C17—H17A109.4
C4—C3—C8118.03 (18)C16—C17—H17B109.4
C8—C3—C2120.50 (17)C16—C17—C18111.09 (16)
C3—C4—H4119.5H17A—C17—H17B108.0
C5—C4—C3120.9 (2)C18—C17—H17A109.4
C5—C4—H4119.5C18—C17—H17B109.4
C4—C5—H5119.7C17—C18—H18A109.7
C6—C5—C4120.5 (2)C17—C18—H18B109.7
C6—C5—H5119.7C17—C18—C19110.05 (15)
C5—C6—H6120.2H18A—C18—H18B108.2
C5—C6—C7119.7 (2)C19—C18—H18A109.7
C7—C6—H6120.2C19—C18—H18B109.7
C6—C7—H7120.0C18—C19—H19A109.4
C6—C7—C8120.1 (2)C18—C19—H19B109.4
C8—C7—H7120.0H19A—C19—H19B108.0
C3—C8—H8119.6C20—C19—C18111.38 (15)
C7—C8—C3120.8 (2)C20—C19—H19A109.4
C7—C8—H8119.6C20—C19—H19B109.4
C10—C9—Si1122.04 (14)N1—C20—C19111.48 (14)
C10—C9—C14117.13 (17)N1—C20—H20A109.3
C14—C9—Si1120.80 (14)N1—C20—H20B109.3
C9—C10—H10119.3C19—C20—H20A109.3
C11—C10—C9121.40 (19)C19—C20—H20B109.3
C11—C10—H10119.3H20A—C20—H20B108.0
Si1—C2—C3—C474.37 (19)C9—Si1—C2—C355.09 (15)
Si1—C2—C3—C8104.58 (17)C9—Si1—C15—N1160.77 (12)
Si1—C9—C10—C11178.33 (15)C9—C10—C11—C120.2 (3)
Si1—C9—C14—C13178.18 (15)C10—C9—C14—C130.0 (3)
N1—C16—C17—C1856.7 (2)C10—C11—C12—C130.0 (3)
C1—Si1—C2—C366.61 (15)C11—C12—C13—C140.1 (3)
C1—Si1—C9—C1015.24 (18)C12—C13—C14—C90.2 (3)
C1—Si1—C9—C14166.66 (15)C14—C9—C10—C110.2 (3)
C1—Si1—C15—N181.20 (15)C15—Si1—C2—C3168.75 (12)
C2—Si1—C9—C10107.45 (16)C15—Si1—C9—C10134.11 (15)
C2—Si1—C9—C1470.65 (16)C15—Si1—C9—C1447.79 (16)
C2—Si1—C15—N143.69 (15)C15—N1—C16—C17178.06 (14)
C2—C3—C4—C5178.46 (17)C15—N1—C20—C19179.63 (14)
C2—C3—C8—C7179.31 (17)C16—N1—C15—Si1177.28 (11)
C3—C4—C5—C60.8 (3)C16—N1—C20—C1956.13 (18)
C4—C3—C8—C70.3 (3)C16—C17—C18—C1955.3 (2)
C4—C5—C6—C70.3 (3)C17—C18—C19—C2055.1 (2)
C5—C6—C7—C80.6 (3)C18—C19—C20—N156.0 (2)
C6—C7—C8—C30.9 (3)C20—N1—C15—Si153.24 (17)
C8—C3—C4—C50.5 (3)C20—N1—C16—C1756.54 (19)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···Br10.82 (2)2.41 (2)3.2242 (15)173.4 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···Br10.82 (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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