organic compounds
4-Chloroanilinium perchlorate–18-crown-16 (1/1)
aOrdered Matter Science Research Center, Collenge of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, People's Republic of China
*Correspondence e-mail: jxyuchunhua@163.com
In the title compound, C6H7ClN+·ClO4−·C12H24O6, the cation forms a 1:1 complex with the crown ether, viz [C6H7ClN-(18-crown-6)]+, in which the –NH3+ unit nests in the crown and interacts with it through bifurcated N—H⋯O hydrogen bonding. All constituents of the structure have crystallographically imposed mirror symmetry except for the H atoms of the –NH3+ group which are disordered across the mirror.
Related literature
The title compound was synthesized as part of a study aimed at finding new ferroelectric materials. For general background to ferroelectric compounds, see: Fu et al. (2009); Ye et al. (2006); Zhang, Xiong et al. (2008); Zhang, Ye et al. (2010). For background to crown ether/ammonium ion complexes, see: Fender et al. (2002); Kryatova et al. (2004).
Experimental
Crystal data
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Refinement
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Data collection: CrystalClear (Rigaku, 2005); cell CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.
Supporting information
https://doi.org/10.1107/S1600536811048859/mw2036sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811048859/mw2036Isup2.hkl
p-chloroaniline (1.28 g, 10 mmol) was dissolved in N,N-dimethyl formamide(DMF) (10 ml) to which an aqueous solution of perchloric acid was dropped slowly with stirring until the pH of the solution was ca 7. 18-crown-6 (2.64 g 10 mmol) was added to the solution and more DMF was added until the initial precipitate dissolved. The solution was filtered to a clean beaker and massive crystals of (I) were obtained via slow evaporation of the DMF solution at room temperature over several weeks.
H atoms attached to C were placed in calculated positions (C—H = 0.93 Å for Csp2 atoms and 0.97 Å for Csp3 atoms) while those attached to N were placed in positions derived from a difference map and the N—H distances adjusted to 0.89 Å. All were included as riding contributions with Uiso values tied to those of the attached atoms (Uiso = 1.2Ueq(Csp2/N) and 1.5Ueq(Csp3)).
We synthesized the title compound, (I), with the aim of finding new ferroelectric materials (Fu et al., 2009; Ye et al., 2006; Zhang, Xiong et al., 2008; Zhang, Ye et al., 2010). There is currently a significant interest in
because of their ability to form noncovalent, hydrogen bonding complexes with ammonium cations both in the solid state and in solution (Fender et al., 2002; Kryatova et al., 2004). In the crystal, the p-chloroanilium cations and 18-crown-6 molecules are associated via hydrogen bonding with the –NH3+ group forming bifurcated hydrogen bonds with all six O atoms of the crown ether molecule (Figure 1, Table 1). Despite the disorder in the –NH3+ group, it is clear that in each orientation the cation forms three bifurcated hydrogen bonds.The title compound was synthesized as part of a study aimed at finding new ferroelectric materials. For general background to ferroelectric compounds, see: Fu et al. (2009); Ye et al. (2006); Zhang, Xiong et al. (2008); Zhang, Ye et al. (2010). For background to crown ether/ammonium ion complexes, see: Fender et al. (2002); Kryatova et al. (2004).
Data collection: CrystalClear (Rigaku, 2005); cell
CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).C6H7ClN+·ClO4−·C12H24O6 | F(000) = 1040 |
Mr = 492.34 | Dx = 1.399 Mg m−3 |
Orthorhombic, Pnma | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2n | Cell parameters from 2820 reflections |
a = 15.726 (3) Å | θ = 3.0–27.5° |
b = 11.525 (2) Å | µ = 0.33 mm−1 |
c = 12.896 (3) Å | T = 293 K |
V = 2337.3 (8) Å3 | Block, colorless |
Z = 4 | 0.35 × 0.32 × 0.28 mm |
Rigaku SCXmini diffractometer | 2820 independent reflections |
Radiation source: fine-focus sealed tube | 2231 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.048 |
ω scans | θmax = 27.5°, θmin = 3.0° |
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005) | h = −20→20 |
Tmin = 0.891, Tmax = 0.912 | k = −14→14 |
23203 measured reflections | l = −16→16 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.045 | H-atom parameters constrained |
wR(F2) = 0.114 | w = 1/[σ2(Fo2) + (0.0418P)2 + 0.9195P] where P = (Fo2 + 2Fc2)/3 |
S = 1.08 | (Δ/σ)max = 0.001 |
2820 reflections | Δρmax = 0.25 e Å−3 |
155 parameters | Δρmin = −0.36 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0159 (11) |
C6H7ClN+·ClO4−·C12H24O6 | V = 2337.3 (8) Å3 |
Mr = 492.34 | Z = 4 |
Orthorhombic, Pnma | Mo Kα radiation |
a = 15.726 (3) Å | µ = 0.33 mm−1 |
b = 11.525 (2) Å | T = 293 K |
c = 12.896 (3) Å | 0.35 × 0.32 × 0.28 mm |
Rigaku SCXmini diffractometer | 2820 independent reflections |
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005) | 2231 reflections with I > 2σ(I) |
Tmin = 0.891, Tmax = 0.912 | Rint = 0.048 |
23203 measured reflections |
R[F2 > 2σ(F2)] = 0.045 | 0 restraints |
wR(F2) = 0.114 | H-atom parameters constrained |
S = 1.08 | Δρmax = 0.25 e Å−3 |
2820 reflections | Δρmin = −0.36 e Å−3 |
155 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 | Occ. (<1) | |
C1 | 0.91237 (18) | 0.2500 | 0.5933 (2) | 0.0575 (8) | |
C2 | 0.87729 (13) | 0.1459 (2) | 0.62262 (16) | 0.0587 (5) | |
H2 | 0.9016 | 0.0763 | 0.6014 | 0.070* | |
C3 | 0.80513 (12) | 0.14605 (17) | 0.68421 (15) | 0.0500 (5) | |
H3 | 0.7808 | 0.0764 | 0.7052 | 0.060* | |
C4 | 0.76968 (15) | 0.2500 | 0.71422 (17) | 0.0378 (5) | |
C5 | 0.53619 (13) | 0.14754 (16) | 0.59540 (14) | 0.0496 (5) | |
H5A | 0.5865 | 0.1403 | 0.5524 | 0.059* | |
H5B | 0.4868 | 0.1508 | 0.5504 | 0.059* | |
C6 | 0.52948 (12) | 0.04615 (17) | 0.66648 (16) | 0.0512 (5) | |
H6A | 0.4820 | 0.0570 | 0.7135 | 0.061* | |
H6B | 0.5194 | −0.0239 | 0.6266 | 0.061* | |
C7 | 0.59921 (13) | −0.04958 (17) | 0.80440 (16) | 0.0544 (5) | |
H7A | 0.5829 | −0.1238 | 0.7751 | 0.065* | |
H7B | 0.5557 | −0.0262 | 0.8535 | 0.065* | |
C8 | 0.68241 (13) | −0.06071 (17) | 0.85833 (16) | 0.0545 (5) | |
H8A | 0.6801 | −0.1240 | 0.9079 | 0.065* | |
H8B | 0.7269 | −0.0775 | 0.8084 | 0.065* | |
C9 | 0.77936 (13) | 0.0436 (2) | 0.96481 (17) | 0.0600 (6) | |
H9A | 0.8262 | 0.0451 | 0.9158 | 0.072* | |
H9B | 0.7837 | −0.0269 | 1.0056 | 0.072* | |
C10 | 0.78372 (15) | 0.1468 (2) | 1.03395 (16) | 0.0644 (6) | |
H10A | 0.7344 | 0.1485 | 1.0791 | 0.077* | |
H10B | 0.8342 | 0.1423 | 1.0770 | 0.077* | |
Cl1 | 0.10405 (4) | 0.2500 | 0.20475 (5) | 0.0469 (2) | |
Cl2 | 1.00340 (6) | 0.2500 | 0.51600 (8) | 0.0976 (4) | |
N1 | 0.69437 (12) | 0.2500 | 0.78054 (15) | 0.0387 (5) | |
H1A | 0.6518 | 0.2853 | 0.7478 | 0.046* | 0.50 |
H1B | 0.7058 | 0.2875 | 0.8392 | 0.046* | 0.50 |
H1C | 0.6796 | 0.1772 | 0.7949 | 0.046* | 0.50 |
O1 | 0.78626 (12) | 0.2500 | 0.97279 (13) | 0.0544 (5) | |
O2 | 0.70060 (8) | 0.04546 (12) | 0.91065 (11) | 0.0527 (4) | |
O3 | 0.60630 (8) | 0.03499 (11) | 0.72394 (10) | 0.0478 (3) | |
O4 | 0.54115 (12) | 0.2500 | 0.65597 (13) | 0.0455 (4) | |
O5 | 0.11758 (11) | 0.14801 (15) | 0.26549 (15) | 0.0858 (6) | |
O6 | 0.01894 (12) | 0.2500 | 0.16435 (17) | 0.0607 (6) | |
O7 | 0.16221 (14) | 0.2500 | 0.11884 (19) | 0.0741 (6) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0407 (14) | 0.090 (2) | 0.0422 (15) | 0.000 | −0.0008 (12) | 0.000 |
C2 | 0.0585 (12) | 0.0672 (14) | 0.0505 (11) | 0.0166 (10) | 0.0025 (10) | −0.0023 (10) |
C3 | 0.0553 (11) | 0.0468 (11) | 0.0479 (10) | 0.0032 (9) | 0.0018 (9) | 0.0011 (8) |
C4 | 0.0391 (12) | 0.0444 (13) | 0.0300 (11) | 0.000 | −0.0071 (10) | 0.000 |
C5 | 0.0565 (11) | 0.0473 (11) | 0.0449 (10) | −0.0017 (9) | −0.0074 (9) | −0.0085 (8) |
C6 | 0.0509 (11) | 0.0433 (11) | 0.0593 (12) | −0.0099 (8) | −0.0062 (9) | −0.0063 (9) |
C7 | 0.0625 (12) | 0.0391 (10) | 0.0615 (12) | −0.0065 (9) | 0.0045 (10) | 0.0074 (9) |
C8 | 0.0642 (12) | 0.0384 (10) | 0.0608 (12) | 0.0091 (9) | 0.0062 (10) | 0.0101 (9) |
C9 | 0.0535 (12) | 0.0660 (14) | 0.0605 (13) | 0.0097 (10) | −0.0093 (10) | 0.0190 (11) |
C10 | 0.0638 (13) | 0.0852 (17) | 0.0443 (11) | 0.0034 (12) | −0.0125 (10) | 0.0145 (11) |
Cl1 | 0.0432 (3) | 0.0385 (3) | 0.0590 (4) | 0.000 | −0.0009 (3) | 0.000 |
Cl2 | 0.0602 (5) | 0.1460 (10) | 0.0868 (7) | 0.000 | 0.0281 (5) | 0.000 |
N1 | 0.0406 (11) | 0.0353 (10) | 0.0402 (11) | 0.000 | −0.0047 (9) | 0.000 |
O1 | 0.0623 (12) | 0.0639 (13) | 0.0371 (10) | 0.000 | −0.0077 (9) | 0.000 |
O2 | 0.0505 (8) | 0.0460 (8) | 0.0615 (8) | 0.0089 (6) | −0.0078 (6) | 0.0064 (6) |
O3 | 0.0491 (7) | 0.0395 (7) | 0.0549 (8) | −0.0047 (5) | −0.0017 (6) | 0.0056 (6) |
O4 | 0.0579 (11) | 0.0386 (10) | 0.0402 (9) | 0.000 | −0.0079 (8) | 0.000 |
O5 | 0.0794 (11) | 0.0744 (12) | 0.1034 (13) | 0.0009 (9) | −0.0148 (10) | 0.0373 (10) |
O6 | 0.0463 (11) | 0.0551 (12) | 0.0807 (14) | 0.000 | −0.0060 (10) | 0.000 |
O7 | 0.0584 (13) | 0.0833 (16) | 0.0807 (15) | 0.000 | 0.0156 (12) | 0.000 |
C1—C2 | 1.374 (3) | C8—O2 | 1.426 (2) |
C1—C2i | 1.374 (3) | C8—H8A | 0.9700 |
C1—Cl2 | 1.744 (3) | C8—H8B | 0.9700 |
C2—C3 | 1.385 (3) | C9—O2 | 1.422 (2) |
C2—H2 | 0.9300 | C9—C10 | 1.489 (3) |
C3—C4 | 1.377 (2) | C9—H9A | 0.9700 |
C3—H3 | 0.9300 | C9—H9B | 0.9700 |
C4—C3i | 1.377 (2) | C10—O1 | 1.427 (2) |
C4—N1 | 1.461 (3) | C10—H10A | 0.9700 |
C5—O4 | 1.418 (2) | C10—H10B | 0.9700 |
C5—C6 | 1.489 (3) | Cl1—O5 | 1.4284 (16) |
C5—H5A | 0.9700 | Cl1—O5i | 1.4284 (16) |
C5—H5B | 0.9700 | Cl1—O6 | 1.436 (2) |
C6—O3 | 1.423 (2) | Cl1—O7 | 1.437 (2) |
C6—H6A | 0.9700 | N1—H1A | 0.8896 |
C6—H6B | 0.9700 | N1—H1B | 0.8899 |
C7—O3 | 1.428 (2) | N1—H1C | 0.8901 |
C7—C8 | 1.487 (3) | O1—C10i | 1.427 (2) |
C7—H7A | 0.9700 | O4—C5i | 1.418 (2) |
C7—H7B | 0.9700 | ||
C2—C1—C2i | 121.7 (3) | C7—C8—H8A | 109.9 |
C2—C1—Cl2 | 119.15 (13) | O2—C8—H8B | 109.9 |
C2i—C1—Cl2 | 119.15 (13) | C7—C8—H8B | 109.9 |
C1—C2—C3 | 119.1 (2) | H8A—C8—H8B | 108.3 |
C1—C2—H2 | 120.5 | O2—C9—C10 | 108.79 (17) |
C3—C2—H2 | 120.5 | O2—C9—H9A | 109.9 |
C4—C3—C2 | 119.59 (19) | C10—C9—H9A | 109.9 |
C4—C3—H3 | 120.2 | O2—C9—H9B | 109.9 |
C2—C3—H3 | 120.2 | C10—C9—H9B | 109.9 |
C3i—C4—C3 | 120.9 (2) | H9A—C9—H9B | 108.3 |
C3i—C4—N1 | 119.52 (12) | O1—C10—C9 | 109.65 (16) |
C3—C4—N1 | 119.52 (12) | O1—C10—H10A | 109.7 |
O4—C5—C6 | 108.56 (15) | C9—C10—H10A | 109.7 |
O4—C5—H5A | 110.0 | O1—C10—H10B | 109.7 |
C6—C5—H5A | 110.0 | C9—C10—H10B | 109.7 |
O4—C5—H5B | 110.0 | H10A—C10—H10B | 108.2 |
C6—C5—H5B | 110.0 | O5—Cl1—O5i | 110.74 (17) |
H5A—C5—H5B | 108.4 | O5—Cl1—O6 | 109.74 (9) |
O3—C6—C5 | 109.35 (15) | O5i—Cl1—O6 | 109.74 (9) |
O3—C6—H6A | 109.8 | O5—Cl1—O7 | 109.15 (10) |
C5—C6—H6A | 109.8 | O5i—Cl1—O7 | 109.15 (10) |
O3—C6—H6B | 109.8 | O6—Cl1—O7 | 108.27 (14) |
C5—C6—H6B | 109.8 | C4—N1—H1A | 109.4 |
H6A—C6—H6B | 108.3 | C4—N1—H1B | 109.5 |
O3—C7—C8 | 109.26 (15) | H1A—N1—H1B | 109.5 |
O3—C7—H7A | 109.8 | C4—N1—H1C | 109.5 |
C8—C7—H7A | 109.8 | H1A—N1—H1C | 109.5 |
O3—C7—H7B | 109.8 | H1B—N1—H1C | 109.5 |
C8—C7—H7B | 109.8 | C10—O1—C10i | 112.8 (2) |
H7A—C7—H7B | 108.3 | C9—O2—C8 | 113.21 (15) |
O2—C8—C7 | 108.89 (15) | C6—O3—C7 | 111.95 (14) |
O2—C8—H8A | 109.9 | C5—O4—C5i | 112.76 (19) |
C2i—C1—C2—C3 | −0.6 (4) | O2—C9—C10—O1 | −65.6 (2) |
Cl2—C1—C2—C3 | 179.84 (17) | C9—C10—O1—C10i | 175.35 (13) |
C1—C2—C3—C4 | 0.4 (3) | C10—C9—O2—C8 | −168.13 (16) |
C2—C3—C4—C3i | −0.3 (4) | C7—C8—O2—C9 | −179.95 (16) |
C2—C3—C4—N1 | −179.03 (18) | C5—C6—O3—C7 | 171.17 (16) |
O4—C5—C6—O3 | −66.0 (2) | C8—C7—O3—C6 | 177.55 (16) |
O3—C7—C8—O2 | 65.9 (2) | C6—C5—O4—C5i | −172.01 (12) |
Symmetry code: (i) x, −y+1/2, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O4 | 0.89 | 2.14 | 2.896 (3) | 142 |
N1—H1A···O3i | 0.89 | 2.21 | 2.9311 (17) | 138 |
N1—H1B···O2i | 0.89 | 2.14 | 2.8952 (18) | 143 |
N1—H1B···O1 | 0.89 | 2.18 | 2.870 (3) | 134 |
N1—H1C···O2 | 0.89 | 2.15 | 2.8952 (18) | 140 |
N1—H1C···O3 | 0.89 | 2.20 | 2.9311 (17) | 139 |
Symmetry code: (i) x, −y+1/2, z. |
Experimental details
Crystal data | |
Chemical formula | C6H7ClN+·ClO4−·C12H24O6 |
Mr | 492.34 |
Crystal system, space group | Orthorhombic, Pnma |
Temperature (K) | 293 |
a, b, c (Å) | 15.726 (3), 11.525 (2), 12.896 (3) |
V (Å3) | 2337.3 (8) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.33 |
Crystal size (mm) | 0.35 × 0.32 × 0.28 |
Data collection | |
Diffractometer | Rigaku SCXmini |
Absorption correction | Multi-scan (CrystalClear; Rigaku, 2005) |
Tmin, Tmax | 0.891, 0.912 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 23203, 2820, 2231 |
Rint | 0.048 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.045, 0.114, 1.08 |
No. of reflections | 2820 |
No. of parameters | 155 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.25, −0.36 |
Computer programs: CrystalClear (Rigaku, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O4 | 0.89 | 2.14 | 2.896 (3) | 141.8 |
N1—H1A···O3i | 0.89 | 2.21 | 2.9311 (17) | 137.5 |
N1—H1B···O2i | 0.89 | 2.14 | 2.8952 (18) | 142.8 |
N1—H1B···O1 | 0.89 | 2.18 | 2.870 (3) | 133.9 |
N1—H1C···O2 | 0.89 | 2.15 | 2.8952 (18) | 140.2 |
N1—H1C···O3 | 0.89 | 2.20 | 2.9311 (17) | 138.7 |
Symmetry code: (i) x, −y+1/2, z. |
Acknowledgements
The author thanks the Ordered Matter Science Research Centre, Southeast University.
References
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We synthesized the title compound, (I), with the aim of finding new ferroelectric materials (Fu et al., 2009; Ye et al., 2006; Zhang, Xiong et al., 2008; Zhang, Ye et al., 2010). There is currently a significant interest in crown ethers because of their ability to form noncovalent, hydrogen bonding complexes with ammonium cations both in the solid state and in solution (Fender et al., 2002; Kryatova et al., 2004). In the crystal, the p-chloroanilium cations and 18-crown-6 molecules are associated via hydrogen bonding with the –NH3+ group forming bifurcated hydrogen bonds with all six O atoms of the crown ether molecule (Figure 1, Table 1). Despite the disorder in the –NH3+ group, it is clear that in each orientation the cation forms three bifurcated hydrogen bonds.