organic compounds
3-(Ammoniomethyl)pyridinium bis(perchlorate)
aLaboratoire de Chimie des Matériaux, Faculté des Sciences de Bizerte, 7021 Zarzouna, Tunisia, and bCEMDRX, Physics Department, University of Coimbra, P-3004-516 Coimbra, Portugal
*Correspondence e-mail: cherif_bennasr@yahoo.fr
In the title molecular salt, C6H10N22+·2ClO4−, the Cl—O bond lengths [anion 1: 1.369 (3)–1.415 (3); anion 2: 1.420 (2)–1.441 (2) Å] and the O—Cl—O angles [anion 1: 105.4 (2)–111.8 (4); anion 2: 107.8 (1)–110.3 (1)°] indicate a slight distortion of the perchlorate anions from regular tetrahedral symmetry. In the crystal, the components are linked into columns along the a-axis direction via N—H⋯O and C—H⋯O hydrogen bonds, with stacks of the organic molecules being surrounded by stacks of perchlorate anions.
Related literature
For general background to perchlorate salts with organic cations, see: Czarnecki et al. (1994); Czupinski et al. (2002, 2006). For related structures, see: Kapplinger & Keutel (1999); Ye et al. (2002)
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2003); cell SAINT (Bruker, 2003); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97.
Supporting information
10.1107/S1600536813012038/lr2104sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536813012038/lr2104Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536813012038/lr2104Isup3.cml
3-ammoniomethylpyrinidinium (1 mmol, 0.108 g) was dissolved in a mixture of distilled water (10 ml) and perchloric acid (0.5 ml).The resultant solution was evaporated at room temperature. Crystals of the title compound, which remained stable under normal conditions of temperature and humidity, were isolated after several days and subjected to X-ray
(yield 64%).All the H-atoms were located in difference Fourier synthesis maps and refined as riding on their parent atoms, using SHELXL97(Sheldrick, 2008) defaults.
Data collection: APEX2 (Bruker, 2003); cell
SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).Fig. 1. A view of the title compound, showing 50% probability displacement ellipsoids and arbitrary spheres for the H atoms. | |
Fig. 2. Partial packing of the title compound, viewed down the b axis, showing columns formed between perchlorate anions and ammonium groups. | |
Fig. 3. The crystal packing of the title compound viewed along the a axis. |
C6H10N22+·2ClO4− | F(000) = 632 |
Mr = 309.06 | Dx = 1.802 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 5314 reflections |
a = 5.1947 (1) Å | θ = 2.3–30.6° |
b = 12.1221 (3) Å | µ = 0.61 mm−1 |
c = 18.2724 (5) Å | T = 293 K |
β = 98.067 (1)° | Block, colourless |
V = 1139.24 (5) Å3 | 0.44 × 0.33 × 0.22 mm |
Z = 4 |
Bruker APEXII CCD area-detector diffractometer | 3509 independent reflections |
Radiation source: fine-focus sealed tube | 3007 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.032 |
ϕ and ω scans | θmax = 30.6°, θmin = 2.0° |
Absorption correction: multi-scan (SADABS; Sheldrick, 2003) | h = −7→7 |
Tmin = 0.765, Tmax = 0.875 | k = −17→17 |
26338 measured reflections | l = −26→26 |
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)] = 0.051 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.148 | H-atom parameters constrained |
S = 1.06 | w = 1/[σ2(Fo2) + (0.0782P)2 + 0.9452P] where P = (Fo2 + 2Fc2)/3 |
3509 reflections | (Δ/σ)max < 0.001 |
163 parameters | Δρmax = 0.70 e Å−3 |
0 restraints | Δρmin = −0.75 e Å−3 |
C6H10N22+·2ClO4− | V = 1139.24 (5) Å3 |
Mr = 309.06 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 5.1947 (1) Å | µ = 0.61 mm−1 |
b = 12.1221 (3) Å | T = 293 K |
c = 18.2724 (5) Å | 0.44 × 0.33 × 0.22 mm |
β = 98.067 (1)° |
Bruker APEXII CCD area-detector diffractometer | 3509 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 2003) | 3007 reflections with I > 2σ(I) |
Tmin = 0.765, Tmax = 0.875 | Rint = 0.032 |
26338 measured reflections |
R[F2 > 2σ(F2)] = 0.051 | 0 restraints |
wR(F2) = 0.148 | H-atom parameters constrained |
S = 1.06 | Δρmax = 0.70 e Å−3 |
3509 reflections | Δρmin = −0.75 e Å−3 |
163 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 | ||
Cl1 | 0.11942 (12) | 0.50919 (5) | 0.12761 (3) | 0.04193 (16) | |
Cl2 | 0.82533 (9) | 0.14688 (4) | 0.09563 (2) | 0.03098 (14) | |
O1 | −0.1534 (5) | 0.4964 (2) | 0.1114 (2) | 0.0912 (10) | |
O2 | 0.2513 (6) | 0.4146 (3) | 0.10993 (17) | 0.0916 (10) | |
O3 | 0.1869 (7) | 0.5993 (4) | 0.0893 (4) | 0.172 (3) | |
O4 | 0.1865 (11) | 0.5226 (5) | 0.2043 (2) | 0.169 (2) | |
O5 | 0.5608 (3) | 0.16338 (19) | 0.10859 (10) | 0.0499 (5) | |
O6 | 0.8768 (4) | 0.22306 (18) | 0.03930 (11) | 0.0523 (5) | |
O7 | 0.9987 (4) | 0.16608 (18) | 0.16220 (10) | 0.0530 (5) | |
O8 | 0.8562 (5) | 0.03757 (18) | 0.07037 (15) | 0.0673 (6) | |
N1 | 0.4671 (4) | 0.26538 (17) | 0.24604 (10) | 0.0400 (4) | |
H1 | 0.4241 | 0.2266 | 0.2068 | 0.048* | |
N2 | 0.3730 (4) | 0.18501 (18) | 0.47673 (11) | 0.0429 (5) | |
H2A | 0.2868 | 0.1768 | 0.5152 | 0.064* | |
H2B | 0.5421 | 0.1917 | 0.4928 | 0.064* | |
H2C | 0.3466 | 0.1263 | 0.4474 | 0.064* | |
C1 | 0.3473 (5) | 0.24549 (19) | 0.30466 (12) | 0.0377 (4) | |
H1A | 0.2182 | 0.1919 | 0.3022 | 0.045* | |
C2 | 0.4155 (4) | 0.30457 (18) | 0.36882 (10) | 0.0318 (4) | |
C3 | 0.6048 (5) | 0.38511 (19) | 0.36950 (12) | 0.0385 (4) | |
H3 | 0.6529 | 0.4269 | 0.4119 | 0.046* | |
C4 | 0.7224 (5) | 0.4036 (2) | 0.30740 (14) | 0.0417 (5) | |
H4 | 0.8501 | 0.4575 | 0.3079 | 0.050* | |
C5 | 0.6497 (5) | 0.3420 (2) | 0.24510 (12) | 0.0392 (5) | |
H5 | 0.7267 | 0.3537 | 0.2028 | 0.047* | |
C6 | 0.2791 (5) | 0.2852 (2) | 0.43480 (13) | 0.0443 (5) | |
H6A | 0.3051 | 0.3487 | 0.4673 | 0.053* | |
H6B | 0.0939 | 0.2781 | 0.4185 | 0.053* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0443 (3) | 0.0361 (3) | 0.0473 (3) | 0.0052 (2) | 0.0129 (2) | 0.0049 (2) |
Cl2 | 0.0309 (2) | 0.0361 (3) | 0.0261 (2) | 0.00110 (17) | 0.00438 (16) | −0.00042 (15) |
O1 | 0.0420 (11) | 0.0839 (18) | 0.152 (3) | 0.0086 (11) | 0.0271 (14) | 0.0586 (18) |
O2 | 0.0762 (17) | 0.104 (2) | 0.0872 (19) | 0.0430 (16) | −0.0138 (14) | −0.0469 (16) |
O3 | 0.078 (2) | 0.132 (3) | 0.295 (6) | −0.031 (2) | −0.009 (3) | 0.148 (4) |
O4 | 0.190 (5) | 0.245 (6) | 0.066 (2) | 0.104 (4) | −0.003 (2) | −0.048 (3) |
O5 | 0.0325 (8) | 0.0816 (14) | 0.0368 (8) | 0.0027 (8) | 0.0089 (6) | −0.0020 (8) |
O6 | 0.0490 (10) | 0.0643 (12) | 0.0455 (9) | −0.0003 (9) | 0.0130 (8) | 0.0202 (9) |
O7 | 0.0437 (9) | 0.0765 (13) | 0.0356 (8) | −0.0043 (9) | −0.0061 (7) | −0.0026 (8) |
O8 | 0.0796 (16) | 0.0426 (11) | 0.0782 (15) | 0.0089 (10) | 0.0055 (12) | −0.0173 (10) |
N1 | 0.0520 (11) | 0.0437 (10) | 0.0241 (7) | −0.0097 (8) | 0.0048 (7) | −0.0045 (7) |
N2 | 0.0466 (11) | 0.0530 (12) | 0.0296 (8) | −0.0131 (9) | 0.0066 (7) | 0.0008 (8) |
C1 | 0.0407 (11) | 0.0434 (11) | 0.0284 (9) | −0.0099 (9) | 0.0028 (8) | −0.0009 (8) |
C2 | 0.0318 (9) | 0.0379 (10) | 0.0256 (8) | 0.0052 (7) | 0.0037 (7) | −0.0005 (7) |
C3 | 0.0416 (11) | 0.0383 (10) | 0.0337 (10) | −0.0002 (9) | −0.0009 (8) | −0.0066 (8) |
C4 | 0.0400 (11) | 0.0409 (11) | 0.0430 (11) | −0.0087 (9) | 0.0016 (9) | 0.0012 (9) |
C5 | 0.0428 (11) | 0.0441 (12) | 0.0318 (9) | −0.0024 (9) | 0.0089 (8) | 0.0049 (8) |
C6 | 0.0426 (12) | 0.0597 (14) | 0.0325 (10) | 0.0077 (10) | 0.0116 (9) | 0.0003 (10) |
Cl1—O3 | 1.369 (3) | N2—H2B | 0.8900 |
Cl1—O2 | 1.397 (2) | N2—H2C | 0.8900 |
Cl1—O4 | 1.405 (4) | C1—C2 | 1.377 (3) |
Cl1—O1 | 1.415 (3) | C1—H1A | 0.9300 |
Cl2—O8 | 1.420 (2) | C2—C3 | 1.385 (3) |
Cl2—O7 | 1.4272 (18) | C2—C6 | 1.500 (3) |
Cl2—O6 | 1.4357 (18) | C3—C4 | 1.380 (3) |
Cl2—O5 | 1.4406 (18) | C3—H3 | 0.9300 |
N1—C5 | 1.329 (3) | C4—C5 | 1.369 (3) |
N1—C1 | 1.334 (3) | C4—H4 | 0.9300 |
N1—H1 | 0.8600 | C5—H5 | 0.9300 |
N2—C6 | 1.482 (3) | C6—H6A | 0.9700 |
N2—H2A | 0.8900 | C6—H6B | 0.9700 |
O3—Cl1—O2 | 111.6 (3) | N1—C1—C2 | 119.7 (2) |
O3—Cl1—O4 | 111.8 (4) | N1—C1—H1A | 120.1 |
O2—Cl1—O4 | 105.4 (2) | C2—C1—H1A | 120.1 |
O3—Cl1—O1 | 107.49 (19) | C1—C2—C3 | 118.16 (19) |
O2—Cl1—O1 | 111.8 (2) | C1—C2—C6 | 120.6 (2) |
O4—Cl1—O1 | 108.8 (3) | C3—C2—C6 | 121.2 (2) |
O8—Cl2—O7 | 110.04 (14) | C4—C3—C2 | 120.2 (2) |
O8—Cl2—O6 | 109.04 (15) | C4—C3—H3 | 119.9 |
O7—Cl2—O6 | 110.33 (13) | C2—C3—H3 | 119.9 |
O8—Cl2—O5 | 109.69 (14) | C5—C4—C3 | 119.5 (2) |
O7—Cl2—O5 | 109.86 (11) | C5—C4—H4 | 120.2 |
O6—Cl2—O5 | 107.84 (12) | C3—C4—H4 | 120.2 |
C5—N1—C1 | 123.42 (19) | N1—C5—C4 | 119.0 (2) |
C5—N1—H1 | 118.3 | N1—C5—H5 | 120.5 |
C1—N1—H1 | 118.3 | C4—C5—H5 | 120.5 |
C6—N2—H2A | 109.5 | N2—C6—C2 | 112.65 (19) |
C6—N2—H2B | 109.5 | N2—C6—H6A | 109.1 |
H2A—N2—H2B | 109.5 | C2—C6—H6A | 109.1 |
C6—N2—H2C | 109.5 | N2—C6—H6B | 109.1 |
H2A—N2—H2C | 109.5 | C2—C6—H6B | 109.1 |
H2B—N2—H2C | 109.5 | H6A—C6—H6B | 107.8 |
C5—N1—C1—C2 | −1.3 (4) | C2—C3—C4—C5 | 0.3 (4) |
N1—C1—C2—C3 | 1.3 (3) | C1—N1—C5—C4 | 0.7 (4) |
N1—C1—C2—C6 | 178.6 (2) | C3—C4—C5—N1 | −0.2 (4) |
C1—C2—C3—C4 | −0.8 (3) | C1—C2—C6—N2 | 78.7 (3) |
C6—C2—C3—C4 | −178.1 (2) | C3—C2—C6—N2 | −104.1 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O5 | 0.86 | 2.16 | 2.901 (3) | 144 |
N1—H1···O7i | 0.86 | 2.36 | 2.945 (3) | 125 |
N2—H2A···O2ii | 0.89 | 2.09 | 2.866 (3) | 146 |
N2—H2A···O6iii | 0.89 | 2.54 | 3.166 (3) | 128 |
N2—H2B···O6ii | 0.89 | 2.10 | 2.925 (3) | 155 |
N2—H2B···O3iv | 0.89 | 2.47 | 2.922 (4) | 112 |
N2—H2B···Cl2ii | 0.89 | 2.96 | 3.600 (2) | 131 |
N2—H2C···O1v | 0.89 | 2.08 | 2.933 (3) | 160 |
N2—H2C···Cl1v | 0.89 | 2.97 | 3.654 (2) | 135 |
C5—H5···O1vi | 0.93 | 2.54 | 3.350 (4) | 145 |
C6—H6A···O8vii | 0.97 | 2.50 | 3.137 (3) | 123 |
Symmetry codes: (i) x−1, y, z; (ii) x, −y+1/2, z+1/2; (iii) x−1, −y+1/2, z+1/2; (iv) −x+1, y−1/2, −z+1/2; (v) −x, y−1/2, −z+1/2; (vi) x+1, y, z; (vii) −x+1, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C6H10N22+·2ClO4− |
Mr | 309.06 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 293 |
a, b, c (Å) | 5.1947 (1), 12.1221 (3), 18.2724 (5) |
β (°) | 98.067 (1) |
V (Å3) | 1139.24 (5) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.61 |
Crystal size (mm) | 0.44 × 0.33 × 0.22 |
Data collection | |
Diffractometer | Bruker APEXII CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 2003) |
Tmin, Tmax | 0.765, 0.875 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 26338, 3509, 3007 |
Rint | 0.032 |
(sin θ/λ)max (Å−1) | 0.716 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.051, 0.148, 1.06 |
No. of reflections | 3509 |
No. of parameters | 163 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.70, −0.75 |
Computer programs: APEX2 (Bruker, 2003), SAINT (Bruker, 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O5 | 0.86 | 2.16 | 2.901 (3) | 143.9 |
N1—H1···O7i | 0.86 | 2.36 | 2.945 (3) | 125.4 |
N2—H2A···O2ii | 0.89 | 2.09 | 2.866 (3) | 145.8 |
N2—H2A···O6iii | 0.89 | 2.54 | 3.166 (3) | 127.6 |
N2—H2B···O6ii | 0.89 | 2.10 | 2.925 (3) | 154.5 |
N2—H2B···O3iv | 0.89 | 2.47 | 2.922 (4) | 112.3 |
N2—H2B···Cl2ii | 0.89 | 2.96 | 3.600 (2) | 130.5 |
N2—H2C···O1v | 0.89 | 2.08 | 2.933 (3) | 159.7 |
N2—H2C···Cl1v | 0.89 | 2.97 | 3.654 (2) | 135.0 |
C5—H5···O1vi | 0.93 | 2.54 | 3.350 (4) | 145 |
C6—H6A···O8vii | 0.97 | 2.50 | 3.137 (3) | 123 |
Symmetry codes: (i) x−1, y, z; (ii) x, −y+1/2, z+1/2; (iii) x−1, −y+1/2, z+1/2; (iv) −x+1, y−1/2, −z+1/2; (v) −x, y−1/2, −z+1/2; (vi) x+1, y, z; (vii) −x+1, y+1/2, −z+1/2. |
Acknowledgements
We would like to acknowledge the support provided by the Secretary of State for Scientific Research and Technology of Tunisia. PSPS acknowledges support by the Fundação para a Ciência e a Tecnologia (FCT), under scholarship SFRH/BPD/84173/2012.
References
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This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
Studies of perchlorate salts containing organic cations have had a great deal of attention in recent years, because of their ferroelectric and dielectric behaviour (Czupinski et al., 2002; Czupinski et al., 2006). It was shown that dynamics of pyridinium cations contributes mainly to the mecanism of solid-solid phase transition and leads ferroelectricity in these molecular-ionic crystals (Czarnecki et al., 1994) Here, we report the synthesis and the crystal structure of the title compound (I), (C6H10N2)(ClO4)2.
The structure consists of one 3-ammoniomethylpyrinidinium dication and two perchlorate anions (Fig. 1). In the crystal, the three H atoms of the ammonium group are involved into N—H···Cl and N—H···O hydrogen bonds: N2—H2C···Cl1(v), N2—H2B···Cl2(ii), N2—H2C···O1(v), N2—H2A··· (O6vi, O2iv) and N2—H2B··· (O6iv, O3vii), the two laters are bifurcated (for the symmetry codes, see Table 1). These hydrogen bonds link the ionic units (NH3+ and [ClO4]-) to form columns running along the a-axis direction (Fig.2) and situated at y = z = 1/2 (Fig.3). The organic groups are located between these columns via two kinds of hydrogen bonds: a bifurcated N—H···O and two C—H···O: N1—H1 (O5, O7viii), C6—H6A···O8(iii) and C5—H5···O1(vi) (Fig. 3, Table 1). No π-π stacking interactions between the organic rings or C—H··· π interactions towards them are observed. It is worth noting that the C—N—C angles of pyridine are very sensitive to protonation: a pyridinium cation always has an expanded angle of the C—N—C in comparison with the parent pydidine. The angle C(5)—N(1)—C(1) [123.4 (2)°] is consistent with the type of pyridinium cation. The hydrogen atom HN(1), which is deprived from its parent, attaches the nitrogen atom. As expected, the [ClO4]- anion has typical tetrahedral geometry where the Cl—O bond lengths and O—Cl—O angles are not equal to one another but vary with the environment around the O atoms. In the title compound, the Cl—O bond lengths vary from 1.369 (3) to 1.415 (3) Å for [Cl(1)O4]- anion and from 1.420 (2) to 1.440 (2) Å for [Cl(2)O4]- anion are comparable to that previuosly reported for the perchlorate anions (Kapplinger & Keutel, 1999). The O—Cl—O angles range from 105.4 (2) to 111.8 (4)° for the first anion and from 109.04 (15) to 110.33 (13)° for the second one. These values, which are characteristic of perchlorate anions (Ye et al., 2002), clearly indicate that the coordination geometry of the Cl(2) atom can be regarded as being a less distorted tetrahedron than the one of the Cl(1). However, for the Cl(2)O4 tetrahedron, all the oxygen atoms are involved in hydrogen bonds, while only three oxygen atoms act as acceptors of hydrogen bonds for the [Cl(1)O4] tetrahedron.