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Acta Crystallogr Sect E Struct Rep Online. 2010 July 1; 66(Pt 7): o1618.
Published online 2010 June 9. doi:  10.1107/S1600536810021392
PMCID: PMC3007038

Benzyl­ammonium tetra­fluoro­borate 18-crown-6 clathrate

Abstract

The reaction of benzyl­ammonium tetra­fluoro­borate and 18-crown-6 in a methano­lic solution yields the title compound, C7H10N+·BF4 ·C12H24O6O6, which displays a supra­molecular structure. The –NH3 + substituent of the benzyl­ammonium cation forms a 1:1 supra­molecular rotator–stator structure by N—H(...)O hydrogen-bonding inter­actions.

Related literature

For similar crown ether clathrates, see: Akutagawa et al. (2002 [triangle]); Kryatova et al. (2004 [triangle]). For their ferroelectric properties, see: Zhang et al. (2009 [triangle]); Ye et al. (2009 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o1618-scheme1.jpg

Experimental

Crystal data

  • C7H10N+·BF4 ·C12H24O6
  • M r = 459.28
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1618-efi1.jpg
  • a = 9.281 (6) Å
  • b = 10.673 (6) Å
  • c = 11.863 (7) Å
  • α = 76.418 (16)°
  • β = 86.244 (17)°
  • γ = 78.274 (15)°
  • V = 1118.2 (12) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.12 mm−1
  • T = 293 K
  • 0.40 × 0.30 × 0.20 mm

Data collection

  • Rigaku SCXmini diffractometer
  • Absorption correction: multi-scan (CrystalClear; Rigaku, 2005 [triangle]) T min = 0.958, T max = 0.976
  • 12286 measured reflections
  • 5057 independent reflections
  • 4153 reflections with I > 2σ(I)
  • R int = 0.031

Refinement

  • R[F 2 > 2σ(F 2)] = 0.045
  • wR(F 2) = 0.103
  • S = 1.03
  • 5057 reflections
  • 280 parameters
  • H-atom parameters constrained
  • Δρmax = 0.25 e Å−3
  • Δρmin = −0.24 e Å−3

Data collection: CrystalClear (Rigaku, 2005 [triangle]); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: PRPKAPPA (Ferguson, 1999 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810021392/im2207sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810021392/im2207Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors are grateful to the starter fund of Southeast University for financial support to purchase the X-ray diffractometer.

supplementary crystallographic information

Comment

There is currently a great deal of interest in crown ethers because of their ability to form non-covalent, H-bonding complexes with ammonium cations both in solid and in solution (Akutagawa et al., 2002; Kryatova et al. 2004). Not only the size of the crown ether, but also the nature of the ammonium cation (–NH4+, RNH3+, R2NH2+, etc) can influence both stoichiometry and stability of these host–guest complexes. The host molecules combine with the guest species by intermolecular interactions, and if the host molecule possesses some specific sites, it is easy to realise high selectivity in ion or molecular recognitions. 18-Crown-6 exhibits the highest affinity for ammonium cations RNH3+, mostly resulting in a 1:1 stoichiometry.

Dielectric permittivity of the title compound was tested to systematically investigate the ferroelectric phase transitions of new materials (Ye et al., 2009; Zhang et al., 2009). The title compound has no dielectric anomaly with the value of 5 and 8 under 1M Hz in the temperature range from 80 to 433 K (m.p.> 453 K), suggesting that the compound should show no distinct phase transition occurring within the measured temperature range.

The title compound is composed of cationic [C7H10N(18-Crown-6)]+ and anionic [BF4] ions in a 1:1 stoichiometry (Fig. 1). Supramolecular rotator-like structures are assembled between benzylammonium cations and 18-crown-6 molecules by N—H···O hydrogen-bonding. Intramolecular N—H···O hydrogen bonding lengths are within the usual range around 2.9 Å. No intermolecular hydrogen bond was observed.

The crown ether adopts a conformation in which the rings show some distortion from planarity, with torsion angles: O5—C8—C9—O3 = 64.5 (2) °; O2—C10—C13—O1 = 68.1 (2) °; C16—C17—O2—C10 = 176.0 (1) °; C10—C13—O1—C14 = 179.5 (1) ° and C8—C9—O3—C11 = 167.9 (1) °. C—N bonds of [C7H10N]+ are almost perpendicular to the mean plane formed by oxygen atoms of the crown ether. Boron shows a slightly distorted tetrahedral coordination by four F ions [range of cis-bond angles = 108.9 (1) – 110.2 (1) °; average distance (B—F) = 1.383 (2)–1.397 (2) Å].

Experimental

C7H10N+BF4 (2 mmol, 0.388 g) and 18-crown-6 (2 mmol, 0.528 g) were dissolved in 15 ml methanol. The resulting precipitate was filtered. Two days later, single crystals suitable for X-ray diffraction analysis were obtained from slow evaporation of the remaining methanolic solution at 0°C (yield: 95%).

Refinement

All hydrogen atoms were calculated geometrically with C—H distances ranging from 0.93 to 0.97 Å and N—H = 0.90 Å. refinement of hydrogen atoms was performed using a riding model with Uiso(H) = 1.2Ueq(C,N).

Figures

Fig. 1.
Molecular structure of the title compound showingh the atom numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.

Crystal data

C7H10N+·BF4·C12H24O6Z = 2
Mr = 459.28F(000) = 488
Triclinic, P1Dx = 1.364 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 9.281 (6) ÅCell parameters from 2953 reflections
b = 10.673 (6) Åθ = 2.9–27.5°
c = 11.863 (7) ŵ = 0.12 mm1
α = 76.418 (16)°T = 293 K
β = 86.244 (17)°Prism, colorless
γ = 78.274 (15)°0.40 × 0.30 × 0.20 mm
V = 1118.2 (12) Å3

Data collection

Rigaku SCXmini diffractometer5057 independent reflections
Radiation source: fine-focus sealed tube4153 reflections with I > 2σ(I)
graphiteRint = 0.031
Detector resolution: 28.5714 pixels mm-1θmax = 27.5°, θmin = 2.7°
ω scansh = −12→12
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)k = −13→13
Tmin = 0.958, Tmax = 0.976l = −15→15
12286 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.103H-atom parameters constrained
S = 1.03w = 1/[σ2(Fo2) + (0.0454P)2 + 0.2316P] where P = (Fo2 + 2Fc2)/3
5057 reflections(Δ/σ)max < 0.001
280 parametersΔρmax = 0.25 e Å3
0 restraintsΔρmin = −0.24 e Å3

Special details

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)

xyzUiso*/Ueq
C8−0.24636 (17)0.50111 (14)0.10270 (14)0.0196 (3)
H8A−0.34970.51750.08410.024*
H8B−0.19730.55620.04180.024*
C9−0.23023 (16)0.53375 (15)0.21673 (14)0.0194 (3)
H9A−0.28040.62320.21530.023*
H9B−0.27380.47510.27850.023*
C100.27734 (17)0.10959 (14)0.00480 (13)0.0189 (3)
H10A0.28600.02380.05730.023*
H10B0.34790.1025−0.05850.023*
C11−0.05246 (17)0.57472 (15)0.33132 (13)0.0203 (3)
H11A−0.10230.53450.40070.024*
H11B−0.09220.66840.31330.024*
C120.31163 (16)0.37847 (15)0.42392 (13)0.0188 (3)
H12A0.33080.29150.47480.023*
H12B0.33450.43970.46570.023*
C130.12451 (16)0.15430 (14)−0.04151 (12)0.0176 (3)
H13A0.11220.2444−0.08610.021*
H13B0.10800.0996−0.09230.021*
C14−0.12985 (16)0.18795 (15)0.01623 (13)0.0186 (3)
H14A−0.19280.14300.07350.022*
H14B−0.13840.1631−0.05630.022*
C15−0.18267 (17)0.33378 (15)−0.00050 (13)0.0194 (3)
H15A−0.11800.3802−0.05470.023*
H15B−0.28110.3590−0.03150.023*
C160.48137 (16)0.27382 (15)0.16325 (13)0.0180 (3)
H16A0.58280.25460.18750.022*
H16B0.46470.35740.10720.022*
C170.45350 (16)0.16760 (15)0.10879 (13)0.0189 (3)
H17A0.52410.15700.04610.023*
H17B0.46480.08490.16600.023*
C180.41154 (16)0.37904 (14)0.31845 (13)0.0184 (3)
H18A0.39240.46500.26600.022*
H18B0.51360.35960.34140.022*
C290.10945 (17)0.55084 (14)0.35178 (13)0.0195 (3)
H29A0.16140.57980.27980.023*
H29B0.12860.59930.40700.023*
O10.02026 (11)0.14543 (10)0.05354 (8)0.0168 (2)
O20.30731 (11)0.20280 (9)0.06498 (9)0.0164 (2)
O3−0.07640 (11)0.51969 (10)0.23695 (8)0.0160 (2)
O40.15806 (11)0.41358 (9)0.39606 (9)0.0170 (2)
O5−0.18295 (11)0.36644 (9)0.10949 (9)0.0171 (2)
O60.38446 (11)0.28133 (10)0.26150 (9)0.0165 (2)
B10.40157 (19)0.76448 (17)0.26818 (15)0.0188 (3)
F10.26267 (12)0.84348 (11)0.26112 (10)0.0428 (3)
F20.42418 (11)0.70503 (10)0.17371 (8)0.0311 (2)
F30.41256 (12)0.66888 (9)0.37036 (8)0.0327 (2)
F40.50826 (12)0.83934 (11)0.26526 (10)0.0401 (3)
N20.08837 (13)0.24571 (11)0.25008 (10)0.0149 (3)
H2A0.17710.26660.24310.022*
H2B0.02080.31510.25880.022*
H2C0.06980.22110.18670.022*
C1−0.34030 (17)0.02500 (15)0.39415 (13)0.0193 (3)
H1A−0.43250.00210.40170.023*
C2−0.23098 (17)−0.03380 (14)0.32762 (13)0.0186 (3)
H2D−0.2498−0.09650.29070.022*
C3−0.09306 (16)0.00054 (14)0.31579 (12)0.0171 (3)
H3A−0.0195−0.04060.27220.020*
C4−0.06450 (16)0.09625 (14)0.36893 (12)0.0158 (3)
C5−0.17497 (17)0.15401 (14)0.43633 (13)0.0189 (3)
H5A−0.15680.21720.47290.023*
C6−0.31203 (17)0.11841 (15)0.44960 (13)0.0202 (3)
H6A−0.38470.15700.49550.024*
C70.08405 (16)0.13519 (14)0.35362 (13)0.0186 (3)
H7A0.10600.16160.42250.022*
H7B0.15890.06010.34460.022*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C80.0179 (8)0.0141 (7)0.0260 (8)−0.0017 (6)−0.0072 (6)−0.0024 (6)
C90.0139 (7)0.0176 (7)0.0268 (8)−0.0023 (6)−0.0005 (6)−0.0053 (6)
C100.0220 (8)0.0162 (7)0.0199 (8)−0.0036 (6)0.0026 (6)−0.0077 (6)
C110.0247 (8)0.0196 (7)0.0169 (7)0.0011 (6)−0.0016 (6)−0.0092 (6)
C120.0185 (8)0.0198 (7)0.0192 (7)−0.0042 (6)−0.0039 (6)−0.0047 (6)
C130.0231 (8)0.0161 (7)0.0149 (7)−0.0055 (6)0.0027 (6)−0.0055 (6)
C140.0175 (7)0.0207 (7)0.0200 (8)−0.0065 (6)−0.0030 (6)−0.0062 (6)
C150.0208 (8)0.0211 (7)0.0169 (7)−0.0050 (6)−0.0054 (6)−0.0030 (6)
C160.0131 (7)0.0207 (7)0.0196 (7)−0.0041 (6)0.0031 (6)−0.0037 (6)
C170.0140 (7)0.0201 (7)0.0208 (8)0.0006 (6)0.0009 (6)−0.0045 (6)
C180.0172 (7)0.0174 (7)0.0230 (8)−0.0060 (6)−0.0012 (6)−0.0072 (6)
C290.0256 (8)0.0151 (7)0.0191 (8)−0.0035 (6)−0.0047 (6)−0.0058 (6)
O10.0165 (5)0.0191 (5)0.0152 (5)−0.0044 (4)0.0002 (4)−0.0040 (4)
O20.0147 (5)0.0149 (5)0.0206 (5)−0.0014 (4)−0.0010 (4)−0.0073 (4)
O30.0139 (5)0.0184 (5)0.0169 (5)−0.0021 (4)−0.0010 (4)−0.0070 (4)
O40.0175 (5)0.0151 (5)0.0189 (5)−0.0033 (4)−0.0019 (4)−0.0044 (4)
O50.0207 (5)0.0131 (5)0.0174 (5)−0.0020 (4)−0.0043 (4)−0.0030 (4)
O60.0157 (5)0.0172 (5)0.0196 (5)−0.0063 (4)0.0032 (4)−0.0080 (4)
B10.0194 (9)0.0190 (8)0.0189 (8)−0.0056 (7)−0.0011 (7)−0.0040 (7)
F10.0308 (6)0.0468 (7)0.0417 (7)0.0136 (5)−0.0010 (5)−0.0099 (5)
F20.0356 (6)0.0352 (6)0.0263 (5)−0.0055 (4)−0.0027 (4)−0.0151 (4)
F30.0475 (6)0.0251 (5)0.0250 (5)−0.0125 (5)−0.0064 (5)0.0013 (4)
F40.0464 (7)0.0388 (6)0.0443 (7)−0.0292 (5)−0.0010 (5)−0.0094 (5)
N20.0148 (6)0.0156 (6)0.0149 (6)−0.0038 (5)0.0005 (5)−0.0040 (5)
C10.0156 (7)0.0234 (8)0.0170 (7)−0.0051 (6)−0.0007 (6)0.0005 (6)
C20.0220 (8)0.0183 (7)0.0170 (7)−0.0072 (6)−0.0020 (6)−0.0037 (6)
C30.0182 (7)0.0181 (7)0.0141 (7)−0.0026 (6)0.0020 (6)−0.0032 (6)
C40.0179 (7)0.0152 (7)0.0127 (7)−0.0053 (6)−0.0033 (6)0.0026 (5)
C50.0249 (8)0.0156 (7)0.0160 (7)−0.0037 (6)−0.0026 (6)−0.0026 (6)
C60.0194 (8)0.0206 (8)0.0176 (7)0.0001 (6)0.0021 (6)−0.0028 (6)
C70.0180 (8)0.0174 (7)0.0185 (7)−0.0054 (6)−0.0042 (6)0.0024 (6)

Geometric parameters (Å, °)

C8—O51.4236 (19)C16—H16B0.9700
C8—C91.497 (2)C17—O21.4303 (19)
C8—H8A0.9700C17—H17A0.9700
C8—H8B0.9700C17—H17B0.9700
C9—O31.4351 (19)C18—O61.4376 (18)
C9—H9A0.9700C18—H18A0.9700
C9—H9B0.9700C18—H18B0.9700
C10—O21.4313 (18)C29—O41.4235 (19)
C10—C131.498 (2)C29—H29A0.9700
C10—H10A0.9700C29—H29B0.9700
C10—H10B0.9700B1—F31.383 (2)
C11—O31.4290 (18)B1—F11.385 (2)
C11—C291.498 (2)B1—F41.387 (2)
C11—H11A0.9700B1—F21.397 (2)
C11—H11B0.9700N2—C71.4946 (19)
C12—O41.4380 (19)N2—H2A0.8900
C12—C181.507 (2)N2—H2B0.8900
C12—H12A0.9700N2—H2C0.8900
C12—H12B0.9700C1—C21.384 (2)
C13—O11.4355 (18)C1—C61.390 (2)
C13—H13A0.9700C1—H1A0.9300
C13—H13B0.9700C2—C31.391 (2)
C14—O11.4395 (19)C2—H2D0.9300
C14—C151.503 (2)C3—C41.395 (2)
C14—H14A0.9700C3—H3A0.9300
C14—H14B0.9700C4—C51.392 (2)
C15—O51.4272 (19)C4—C71.507 (2)
C15—H15A0.9700C5—C61.389 (2)
C15—H15B0.9700C5—H5A0.9300
C16—O61.4322 (18)C6—H6A0.9300
C16—C171.501 (2)C7—H7A0.9700
C16—H16A0.9700C7—H7B0.9700
O5—C8—C9109.25 (12)O2—C17—H17B109.9
O5—C8—H8A109.8C16—C17—H17B109.9
C9—C8—H8A109.8H17A—C17—H17B108.3
O5—C8—H8B109.8O6—C18—C12108.68 (12)
C9—C8—H8B109.8O6—C18—H18A110.0
H8A—C8—H8B108.3C12—C18—H18A110.0
O3—C9—C8108.54 (12)O6—C18—H18B110.0
O3—C9—H9A110.0C12—C18—H18B110.0
C8—C9—H9A110.0H18A—C18—H18B108.3
O3—C9—H9B110.0O4—C29—C11107.80 (12)
C8—C9—H9B110.0O4—C29—H29A110.1
H9A—C9—H9B108.4C11—C29—H29A110.1
O2—C10—C13108.95 (12)O4—C29—H29B110.1
O2—C10—H10A109.9C11—C29—H29B110.1
C13—C10—H10A109.9H29A—C29—H29B108.5
O2—C10—H10B109.9C13—O1—C14112.74 (12)
C13—C10—H10B109.9C17—O2—C10111.77 (11)
H10A—C10—H10B108.3C11—O3—C9111.85 (11)
O3—C11—C29109.20 (12)C29—O4—C12113.18 (11)
O3—C11—H11A109.8C8—O5—C15111.32 (11)
C29—C11—H11A109.8C16—O6—C18110.94 (11)
O3—C11—H11B109.8F3—B1—F1109.87 (14)
C29—C11—H11B109.8F3—B1—F4109.19 (13)
H11A—C11—H11B108.3F1—B1—F4110.24 (14)
O4—C12—C18113.11 (12)F3—B1—F2109.64 (14)
O4—C12—H12A109.0F1—B1—F2108.85 (13)
C18—C12—H12A109.0F4—B1—F2109.04 (14)
O4—C12—H12B109.0C7—N2—H2A109.5
C18—C12—H12B109.0C7—N2—H2B109.5
H12A—C12—H12B107.8H2A—N2—H2B109.5
O1—C13—C10109.27 (13)C7—N2—H2C109.5
O1—C13—H13A109.8H2A—N2—H2C109.5
C10—C13—H13A109.8H2B—N2—H2C109.5
O1—C13—H13B109.8C2—C1—C6119.87 (14)
C10—C13—H13B109.8C2—C1—H1A120.1
H13A—C13—H13B108.3C6—C1—H1A120.1
O1—C14—C15112.86 (12)C1—C2—C3120.23 (14)
O1—C14—H14A109.0C1—C2—H2D119.9
C15—C14—H14A109.0C3—C2—H2D119.9
O1—C14—H14B109.0C2—C3—C4120.39 (14)
C15—C14—H14B109.0C2—C3—H3A119.8
H14A—C14—H14B107.8C4—C3—H3A119.8
O5—C15—C14108.15 (12)C5—C4—C3118.85 (14)
O5—C15—H15A110.1C5—C4—C7120.99 (14)
C14—C15—H15A110.1C3—C4—C7120.15 (13)
O5—C15—H15B110.1C6—C5—C4120.80 (14)
C14—C15—H15B110.1C6—C5—H5A119.6
H15A—C15—H15B108.4C4—C5—H5A119.6
O6—C16—C17109.34 (12)C5—C6—C1119.85 (14)
O6—C16—H16A109.8C5—C6—H6A120.1
C17—C16—H16A109.8C1—C6—H6A120.1
O6—C16—H16B109.8N2—C7—C4111.37 (12)
C17—C16—H16B109.8N2—C7—H7A109.4
H16A—C16—H16B108.3C4—C7—H7A109.4
O2—C17—C16109.06 (12)N2—C7—H7B109.4
O2—C17—H17A109.9C4—C7—H7B109.4
C16—C17—H17A109.9H7A—C7—H7B108.0
O5—C8—C9—O364.50 (15)C9—C8—O5—C15−174.28 (12)
O2—C10—C13—O1−68.12 (15)C14—C15—O5—C8−173.89 (12)
O1—C14—C15—O5−64.33 (16)C17—C16—O6—C18177.97 (12)
O6—C16—C17—O264.18 (15)C12—C18—O6—C16−177.47 (12)
O4—C12—C18—O6−62.79 (15)C6—C1—C2—C3−0.2 (2)
O3—C11—C29—O4−68.82 (15)C1—C2—C3—C4−1.2 (2)
C10—C13—O1—C14179.48 (11)C2—C3—C4—C51.7 (2)
C15—C14—O1—C13−86.11 (15)C2—C3—C4—C7−178.64 (13)
C16—C17—O2—C10176.00 (12)C3—C4—C5—C6−0.7 (2)
C13—C10—O2—C17−178.41 (12)C7—C4—C5—C6179.59 (13)
C29—C11—O3—C9177.14 (12)C4—C5—C6—C1−0.7 (2)
C8—C9—O3—C11167.91 (12)C2—C1—C6—C51.1 (2)
C11—C29—O4—C12−177.59 (11)C5—C4—C7—N2−90.62 (17)
C18—C12—O4—C29−76.33 (15)C3—C4—C7—N289.72 (17)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N2—H2A···O60.891.992.866 (2)167
N2—H2B···O30.892.152.986 (2)157
N2—H2C···O10.892.052.936 (2)173

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: IM2207).

References

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