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ISSN: 2056-9890

4,4′-(1,3,4-Oxa­diazole-2,5-diyl)di­pyri­dinium dibromide monohydrate

aOrdered Matter Science Research Center, College of Chemistry and Chemical, Engineering, Southeast University, Nanjing 211189, People's Republic of China
*Correspondence e-mail: zhangshelley86@hotmail.com

(Received 16 October 2010; accepted 12 November 2010; online 17 November 2010)

In the title compound, C12H10N4O+·2Br·H2O, the cation is approximately planar: the terminal rings make a dihedral angle of 7.91 (6)° with each other and dihedral angles of 6.02 (1) and 6.50 (8)° with the central ring. It is linked to the bromide anions and water mol­ecules by N—H⋯Br hydrogen bonds. In addition, O—H⋯Br and N—H⋯Br hydrogen bonds link these units into a three-dimensional network. C—H⋯N, C—H⋯Br and N—H⋯O inter­actions are also observed.

Related literature

For background to the development of ferroelectric pure organic or inorganic compounds, see: Haertling et al. (1999[Haertling, G. H. (1999). J. Am. Ceram. Soc. 82, 797-810.]); Homes et al. (2001[Homes, C. C., Vogt, T., Shapiro, S. M., Wakimoto, S. & Ramirez, A. P. (2001). Science, 293, 673-676.]). For the synthesis of compounds with potential piezoelectric and ferroelectric properties, see: Ye et al. (2006[Ye, Q., Song, Y. M., Wang, G. X., Chen, K., Fu, D. W., Chan, P. W. H., Zhu, J. S., Huang, S. D. & Xiong, R. G. (2006). J. Am. Chem. Soc. 20, 6554-6555.]); Zhang et al. (2008[Zhang, W., Xiong, R. G. & Huang, S. P. (2008). J. Am. Chem. Soc. 32, 10468-10469.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C12H10N4O+·2Br·H2O

  • Mr = 404.08

  • Monoclinic, P 21 /n

  • a = 5.2917 (11) Å

  • b = 17.531 (4) Å

  • c = 15.909 (3) Å

  • β = 95.42 (3)°

  • V = 1469.3 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 5.52 mm−1

  • T = 293 K

  • 0.20 × 0.20 × 0.20 mm

Data collection
  • Rigaku Mercury2 diffractometer

  • Absorption correction: multi-scan (CrystalClear; Rigaku, 2005[Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.863, Tmax = 1.000

  • 14787 measured reflections

  • 3351 independent reflections

  • 2057 reflections with I > 2σ(I)

  • Rint = 0.124

Refinement
  • R[F2 > 2σ(F2)] = 0.061

  • wR(F2) = 0.111

  • S = 1.06

  • 3351 reflections

  • 182 parameters

  • 4 restraints

  • H-atom parameters constrained

  • Δρmax = 0.50 e Å−3

  • Δρmin = −0.56 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2A⋯Br2 1.02 2.38 3.277 (6) 147
O2—H2A⋯Br2 1.02 2.38 3.277 (6) 147
N1—H1A⋯Br1i 0.86 2.36 3.158 (7) 155
C12—H12A⋯N3ii 0.93 2.40 3.311 (11) 167
C10—H10A⋯Br1iii 0.93 2.75 3.595 (9) 151
N4—H4A⋯O2iii 0.86 1.78 2.608 (9) 162
C1—H1B⋯Br1iv 0.93 2.74 3.597 (9) 154
C9—H9A⋯Br2iv 0.93 2.92 3.719 (8) 145
Symmetry codes: (i) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (ii) -x+1, -y+1, -z+2; (iii) x-1, y, z; (iv) [-x-{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: CrystalClear (Rigaku, 2005[Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.]); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

At present, much attention in ferroelectric material field is focused on developing ferroelectric pure organic or inorganic compounds (Haertling et al. 1999; Homes et al. 2001). Recently we have reported the synthesis of a variety of compounds (Ye et al., 2006; Zhang et al., 2008), which have potential piezoelectric and ferroelectric. properties. In order to find more dielectric ferroelectric materials, we investigate the physical properties of the title compound(Fig. 1). The dielectric constant of the title compound as a function of temperature indicates that the permittivity is basically temperature-independent (dielectric constant equaling to 3.6 to 4.7), suggesting that this compound should be not a real ferroelectrics or there may be no distinct phase transition occurred within the measured temperature range. Similarly, below the melting point (365 K) of the compound, the dielectric constant as a function of temperature also goes smoothly, and there is no dielectric anomaly observed (dielectric constant equaling to 3.5 to 4.6).Herein, we report the synthesis and crystal structure of the title compound.

The asymmetric unit of (I) consists of one bpo dication, two bromide anions and one water molecule, linked by hydrogen bonds (Fig. 2). The bond lengths and angles are in normal ranges (Allen et al., 1987). In the dication, rings A (N1/C1–C5), B (C6/N2/N3/C7/O1) and C (N4/C8–C12) are each planar. The dihedral angles between the rings are A/B = 6.02 (1), A/C =7.91 (6) and B/C =6.50 (8). As can be seen from the packing diagram (Fig. 2), molecules are connected via intermolecular N—H···Br and C—H···Br hydrogen bonds to form a three dimensional network. Dipole–dipole and van der Waals interactions are effective in the molecular packing.

Related literature top

For background to the development of ferroelectric pure organic or inorganic compounds, see: Haertling et al. (1999); Homes et al. (2001). For the synthesis of compounds with potential piezoelectric and ferroelectric. properties, see: Ye et al. (2006); Zhang et al. (2008). For bond-length data, see: Allen et al. (1987).

Experimental top

A mix of 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (2.24 g, 0.01 mol) and hydrobromic acid (4.05 g,0.02 mol) in methanol (20 ml) was stirred until clear. After several days, the title compound was formed and recrystallized from solution to afford colourlesss prismatic crystals suitable for X-ray analysis.

Refinement top

H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93 Å and Uiso(H) = 1.2eq(C).

Structure description top

At present, much attention in ferroelectric material field is focused on developing ferroelectric pure organic or inorganic compounds (Haertling et al. 1999; Homes et al. 2001). Recently we have reported the synthesis of a variety of compounds (Ye et al., 2006; Zhang et al., 2008), which have potential piezoelectric and ferroelectric. properties. In order to find more dielectric ferroelectric materials, we investigate the physical properties of the title compound(Fig. 1). The dielectric constant of the title compound as a function of temperature indicates that the permittivity is basically temperature-independent (dielectric constant equaling to 3.6 to 4.7), suggesting that this compound should be not a real ferroelectrics or there may be no distinct phase transition occurred within the measured temperature range. Similarly, below the melting point (365 K) of the compound, the dielectric constant as a function of temperature also goes smoothly, and there is no dielectric anomaly observed (dielectric constant equaling to 3.5 to 4.6).Herein, we report the synthesis and crystal structure of the title compound.

The asymmetric unit of (I) consists of one bpo dication, two bromide anions and one water molecule, linked by hydrogen bonds (Fig. 2). The bond lengths and angles are in normal ranges (Allen et al., 1987). In the dication, rings A (N1/C1–C5), B (C6/N2/N3/C7/O1) and C (N4/C8–C12) are each planar. The dihedral angles between the rings are A/B = 6.02 (1), A/C =7.91 (6) and B/C =6.50 (8). As can be seen from the packing diagram (Fig. 2), molecules are connected via intermolecular N—H···Br and C—H···Br hydrogen bonds to form a three dimensional network. Dipole–dipole and van der Waals interactions are effective in the molecular packing.

For background to the development of ferroelectric pure organic or inorganic compounds, see: Haertling et al. (1999); Homes et al. (2001). For the synthesis of compounds with potential piezoelectric and ferroelectric. properties, see: Ye et al. (2006); Zhang et al. (2008). For bond-length data, see: Allen et al. (1987).

Computing details top

Data collection: CrystalClear (Rigaku, 2005); cell refinement: 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: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Perspective structure of the title compound, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. The crystal packing of the title compound viewed along the a axis showing the hydrogen bondings network. Some of the H atoms have been ommitted for clarity.
4,4'-(1,3,4-Oxadiazole-2,5-diyl)dipyridinium dibromide monohydrate top
Crystal data top
C12H10N4O+·2Br·H2OF(000) = 792
Mr = 404.08Dx = 1.827 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 3351 reflections
a = 5.2917 (11) Åθ = 2.6–27.5°
b = 17.531 (4) ŵ = 5.52 mm1
c = 15.909 (3) ÅT = 293 K
β = 95.42 (3)°Prism, colorless
V = 1469.3 (5) Å30.20 × 0.20 × 0.20 mm
Z = 4
Data collection top
Rigaku Mercury2
diffractometer
3351 independent reflections
Radiation source: fine-focus sealed tube2057 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.124
Detector resolution: 13.6612 pixels mm-1θmax = 27.5°, θmin = 3.5°
CCD_Profile_fitting scansh = 66
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
k = 2222
Tmin = 0.863, Tmax = 1.000l = 2020
14787 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.061H-atom parameters constrained
wR(F2) = 0.111 w = 1/[σ2(Fo2) + (0.0181P)2 + 0.7564P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max < 0.001
3351 reflectionsΔρmax = 0.50 e Å3
182 parametersΔρmin = 0.56 e Å3
4 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0179 (12)
Crystal data top
C12H10N4O+·2Br·H2OV = 1469.3 (5) Å3
Mr = 404.08Z = 4
Monoclinic, P21/nMo Kα radiation
a = 5.2917 (11) ŵ = 5.52 mm1
b = 17.531 (4) ÅT = 293 K
c = 15.909 (3) Å0.20 × 0.20 × 0.20 mm
β = 95.42 (3)°
Data collection top
Rigaku Mercury2
diffractometer
3351 independent reflections
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
2057 reflections with I > 2σ(I)
Tmin = 0.863, Tmax = 1.000Rint = 0.124
14787 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0614 restraints
wR(F2) = 0.111H-atom parameters constrained
S = 1.06Δρmax = 0.50 e Å3
3351 reflectionsΔρmin = 0.56 e Å3
182 parameters
Special details top

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) top
xyzUiso*/Ueq
Br10.18714 (17)0.55914 (5)0.63099 (6)0.0437 (3)
O10.0187 (10)0.3400 (3)0.9429 (3)0.0319 (13)
C120.1428 (16)0.5397 (5)0.8894 (5)0.037 (2)
H12A0.29420.54780.92290.044*
N10.0017 (14)0.0806 (4)1.0711 (5)0.043 (2)
H1A0.03750.03601.08850.051*
N30.3649 (13)0.4071 (4)0.9798 (5)0.0391 (18)
C70.1437 (15)0.4071 (5)0.9364 (5)0.031 (2)
N20.3954 (13)0.3359 (4)1.0176 (5)0.0390 (18)
C20.0995 (16)0.1868 (4)0.9865 (6)0.039 (2)
H2B0.20920.21170.94630.047*
N40.1899 (14)0.5864 (4)0.7948 (5)0.0413 (19)
H4A0.25720.62350.76530.050*
C40.2829 (16)0.1829 (5)1.0785 (5)0.038 (2)
H4B0.43310.20561.10100.045*
C60.1883 (15)0.2988 (4)0.9944 (5)0.033 (2)
C90.2029 (15)0.4591 (5)0.8382 (6)0.039 (2)
H9A0.28380.41190.83650.046*
C10.1564 (16)0.1146 (5)1.0141 (6)0.040 (2)
H1B0.30480.09030.99260.048*
C30.1220 (15)0.2216 (4)1.0193 (5)0.032 (2)
C80.0254 (15)0.4693 (4)0.8867 (5)0.031 (2)
C110.0294 (18)0.5977 (5)0.8412 (6)0.043 (2)
H11A0.10690.64530.84110.052*
C100.3083 (17)0.5193 (5)0.7925 (6)0.042 (2)
H10A0.46240.51330.75990.050*
C50.2213 (17)0.1121 (5)1.1036 (6)0.043 (2)
H5A0.32930.08561.14280.051*
Br20.19209 (18)0.82026 (5)0.74803 (7)0.0527 (4)
O20.6881 (12)0.7150 (3)0.7191 (4)0.0601 (19)
H2D0.67260.76110.70280.072*
H2A0.51060.73670.70600.072*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0439 (6)0.0500 (6)0.0366 (6)0.0134 (5)0.0010 (4)0.0015 (4)
O10.033 (3)0.037 (3)0.026 (3)0.001 (3)0.000 (3)0.001 (3)
C120.032 (5)0.042 (5)0.036 (6)0.007 (4)0.001 (4)0.000 (4)
N10.048 (5)0.040 (4)0.041 (5)0.001 (4)0.010 (4)0.005 (4)
N30.037 (4)0.035 (4)0.043 (5)0.006 (4)0.009 (4)0.004 (4)
C70.032 (5)0.039 (5)0.022 (5)0.009 (4)0.000 (4)0.003 (4)
N20.038 (4)0.039 (4)0.038 (5)0.005 (4)0.007 (4)0.004 (4)
C20.038 (5)0.043 (5)0.034 (6)0.001 (4)0.001 (4)0.002 (4)
N40.042 (5)0.049 (5)0.033 (5)0.017 (4)0.004 (4)0.006 (4)
C40.037 (5)0.047 (5)0.029 (6)0.003 (4)0.002 (4)0.000 (4)
C60.036 (5)0.036 (5)0.026 (5)0.003 (4)0.007 (4)0.001 (4)
C90.035 (5)0.048 (5)0.033 (5)0.009 (5)0.002 (4)0.004 (4)
C10.037 (5)0.041 (5)0.043 (6)0.008 (4)0.005 (5)0.006 (5)
C30.035 (5)0.038 (5)0.026 (5)0.002 (4)0.007 (4)0.003 (4)
C80.032 (5)0.034 (5)0.027 (5)0.002 (4)0.005 (4)0.005 (4)
C110.050 (6)0.040 (5)0.042 (6)0.000 (5)0.010 (5)0.003 (5)
C100.034 (5)0.058 (6)0.033 (6)0.006 (5)0.001 (4)0.007 (5)
C50.048 (6)0.047 (6)0.034 (6)0.006 (5)0.008 (5)0.005 (4)
Br20.0432 (6)0.0618 (7)0.0532 (8)0.0114 (5)0.0060 (5)0.0022 (5)
O20.061 (4)0.046 (4)0.073 (5)0.022 (4)0.002 (4)0.016 (4)
Geometric parameters (Å, º) top
O1—C71.359 (9)N4—C101.331 (10)
O1—C61.364 (9)N4—H4A0.8600
C12—C111.376 (11)C4—C51.353 (11)
C12—C81.382 (10)C4—C31.386 (11)
C12—H12A0.9300C4—H4B0.9300
N1—C11.318 (10)C6—C31.463 (11)
N1—C51.345 (11)C9—C101.371 (11)
N1—H1A0.8600C9—C81.383 (11)
N3—C71.301 (10)C9—H9A0.9300
N3—N21.388 (9)C1—H1B0.9300
C7—C81.453 (11)C11—H11A0.9300
N2—C61.297 (10)C10—H10A0.9300
C2—C31.379 (11)C5—H5A0.9300
C2—C11.382 (11)O2—H2D0.8501
C2—H2B0.9300O2—H2A1.0162
N4—C111.331 (11)
C7—O1—C6101.9 (6)O1—C6—C3119.4 (7)
C11—C12—C8118.1 (8)C10—C9—C8119.2 (8)
C11—C12—H12A120.9C10—C9—H9A120.4
C8—C12—H12A120.9C8—C9—H9A120.4
C1—N1—C5123.2 (8)N1—C1—C2119.4 (8)
C1—N1—H1A118.4N1—C1—H1B120.3
C5—N1—H1A118.4C2—C1—H1B120.3
C7—N3—N2106.9 (6)C2—C3—C4119.2 (8)
N3—C7—O1112.3 (7)C2—C3—C6121.6 (8)
N3—C7—C8127.5 (7)C4—C3—C6119.3 (8)
O1—C7—C8120.2 (7)C12—C8—C9120.0 (8)
C6—N2—N3105.5 (7)C12—C8—C7118.9 (7)
C3—C2—C1119.1 (9)C9—C8—C7121.1 (7)
C3—C2—H2B120.4N4—C11—C12120.7 (8)
C1—C2—H2B120.4N4—C11—H11A119.6
C11—N4—C10122.0 (8)C12—C11—H11A119.6
C11—N4—H4A119.0N4—C10—C9119.9 (8)
C10—N4—H4A119.0N4—C10—H10A120.0
C5—C4—C3120.0 (8)C9—C10—H10A120.0
C5—C4—H4B120.0N1—C5—C4119.2 (9)
C3—C4—H4B120.0N1—C5—H5A120.4
N2—C6—O1113.3 (7)C4—C5—H5A120.4
N2—C6—C3127.2 (8)H2D—O2—H2A61.4
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2A···Br21.022.383.277 (6)147
O2—H2A···Br21.022.383.277 (6)147
N1—H1A···Br1i0.862.363.158 (7)155
C12—H12A···N3ii0.932.403.311 (11)167
C10—H10A···Br1iii0.932.753.595 (9)151
N4—H4A···O2iii0.861.782.608 (9)162
C1—H1B···Br1iv0.932.743.597 (9)154
C9—H9A···Br2iv0.932.923.719 (8)145
Symmetry codes: (i) x1/2, y+1/2, z+1/2; (ii) x+1, y+1, z+2; (iii) x1, y, z; (iv) x1/2, y1/2, z+3/2.

Experimental details

Crystal data
Chemical formulaC12H10N4O+·2Br·H2O
Mr404.08
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)5.2917 (11), 17.531 (4), 15.909 (3)
β (°) 95.42 (3)
V3)1469.3 (5)
Z4
Radiation typeMo Kα
µ (mm1)5.52
Crystal size (mm)0.20 × 0.20 × 0.20
Data collection
DiffractometerRigaku Mercury2
Absorption correctionMulti-scan
(CrystalClear; Rigaku, 2005)
Tmin, Tmax0.863, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
14787, 3351, 2057
Rint0.124
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.061, 0.111, 1.06
No. of reflections3351
No. of parameters182
No. of restraints4
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.50, 0.56

Computer programs: CrystalClear (Rigaku, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2A···Br21.022.383.277 (6)147.1
O2—H2A···Br21.022.383.277 (6)147.1
N1—H1A···Br1i0.862.363.158 (7)155.4
C12—H12A···N3ii0.932.403.311 (11)167.1
C10—H10A···Br1iii0.932.753.595 (9)151.2
N4—H4A···O2iii0.861.782.608 (9)162.3
C1—H1B···Br1iv0.932.743.597 (9)153.7
C9—H9A···Br2iv0.932.923.719 (8)145.2
Symmetry codes: (i) x1/2, y+1/2, z+1/2; (ii) x+1, y+1, z+2; (iii) x1, y, z; (iv) x1/2, y1/2, z+3/2.
 

Acknowledgements

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

References

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