1,4-Dimethyl­piperazine-1,4-diium dibromide dihydrate

doi:10.1107/S1600536812020272

Acta Crystallogr Sect E Struct Rep Online. 2012 June 1; 68(Pt 6): o1703.

Published online 2012 May 12. doi: 10.1107/S1600536812020272

PMCID: PMC3379296

1,4-Dimethylpiperazine-1,4-diium dibromide dihydrate

Su-Wen Sun^a^*

^aCollege of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, People’s Republic of China

Correspondence e-mail: sunsuwen_5127/at/163.com

Received April 25, 2012; Accepted May 5, 2012.

This is an open-access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Abstract

In the title hydrated molecular salt, C₆H₁₆N₂ ²⁺·2Br⁻·2H₂O, the complete 1,4-dimethylpiperazine-1,4-diium dication is generated by crystallographic inversion symmetry and both exocyclic C—N bonds are in equatorial orientations. In the crystal, the components are linked by N—H (...)

O and O—H

Br hydrogen bonds, generating chains propagating in [110].

Related literature

For background to molecular ferroelectrics, see: Fu et al. (2009

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Object name is e-68-o1703-scheme1.jpg Object name is e-68-o1703-scheme1.jpg

Experimental

Crystal data

C₆H₁₆N₂ ²⁺·2Br⁻·2H₂O
M _r = 312.06
Triclinic,
a = 6.2975 (13) Å
b = 7.0180 (14) Å
c = 7.2143 (14) Å
α = 71.54 (3)°
β = 86.62 (3)°
γ = 85.54 (3)°
V = 301.32 (10) Å³
Z = 1
Mo Kα radiation
μ = 6.70 mm⁻¹
T = 293 K
0.30 × 0.30 × 0.20 mm

Data collection

Rigaku SCXmini CCD diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005 ) T _min = 0.154, T _max = 0.262
3084 measured reflections
1370 independent reflections
1131 reflections with I > 2σ(I)
R _int = 0.067

Refinement

R[F ² > 2σ(F ²)] = 0.059
wR(F ²) = 0.169
S = 1.02
1370 reflections
64 parameters
3 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.80 e Å⁻³
Δρ_min = −1.12 e Å⁻³

Data collection: CrystalClear (Rigaku, 2005

); cell refinement: 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.

Table 1

Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812020272/hb6759sup1.cif

Click here to view.^{(13K, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812020272/hb6759Isup2.hkl

Click here to view.^{(68K, hkl)}

Supplementary material file. DOI: 10.1107/S1600536812020272/hb6759Isup3.cml

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

Acknowledgments

The author is grateful to the starter fund of Southeast University for financial support to buy the X-ray diffractometer.

supplementary crystallographic information

Comment

Dielectric constant measurements of compounds as a function of temperature is the basic methods to find the materials which possess potential ferroelectric phase changes (Fu et al., 2009). The dielectric constant of the title compound has been measured,but showed no dielectric disuniformity in the range 113–353 K(mp.403–410 K).

The asymmetric unit of the title compound is shown in Fig. 1. crystallized in the monoclinic P-1 space group, The crystal packing Fig. 2 features weak intermolecular O—H···Br and N—H···O hydrogen bonds (Table 1).

Experimental

1,4-Dimethyl-piperazine (0.57 g) and an excess of hydrobromic acid (0.95 g) were dissolved in methanol without any precipitation under stirring at room temperature. Colourless blocks of the title compound were obtained by slow evaporation of a methanol solution at room temperature over two days.

Figures

Fig. 1.

The molecular structure of the title compound with 30% probability displacement ellipsoids.

Fig. 2.

A view of the packing of the title compound, stacking along the b axis. Dashed lines indicate hydrogen bonds.

Crystal data

C₆H₁₆N₂²⁺·2Br⁻·2H₂O	V = 301.32 (10) Å³
M_r = 312.06	Z = 1
Triclinic, P1	F(000) = 156
Hall symbol: -P 1	D_x = 1.720 Mg m⁻³
a = 6.2975 (13) Å	Mo Kα radiation, λ = 0.71073 Å
b = 7.0180 (14) Å	θ = 3.1–27.5°
c = 7.2143 (14) Å	µ = 6.70 mm⁻¹
α = 71.54 (3)°	T = 293 K
β = 86.62 (3)°	Block, colorless
γ = 85.54 (3)°	0.30 × 0.30 × 0.20 mm

Data collection

Rigaku SCXmini CCD diffractometer	1370 independent reflections
Radiation source: fine-focus sealed tube	1131 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.067
Detector resolution: 13.6612 pixels mm^-1	θ_max = 27.5°, θ_min = 3.1°
CCD_Profile_fitting scans	h = −8→7
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	k = −9→9
T_min = 0.154, T_max = 0.262	l = −9→9
3084 measured reflections

Refinement

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)] = 0.059	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.169	H atoms treated by a mixture of independent and constrained refinement
S = 1.02	w = 1/[σ²(F_o²) + (0.0897P)² + 0.3362P] where P = (F_o² + 2F_c²)/3
1370 reflections	(Δ/σ)_max = 0.024
64 parameters	Δρ_max = 0.80 e Å⁻³
3 restraints	Δρ_min = −1.12 e Å⁻³

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)

	x	y	z	U_iso*/U_eq
N1	0.0403 (8)	0.3473 (7)	0.6882 (7)	0.0319 (11)
H1A	−0.0362	0.2477	0.6754	0.038*
C2	−0.1103 (10)	0.5311 (10)	0.6709 (9)	0.0355 (13)
H2A	−0.2225	0.4973	0.7717	0.043*
H2B	−0.0331	0.6371	0.6904	0.043*
C3	0.2067 (9)	0.3955 (10)	0.5259 (9)	0.0346 (13)
H3A	0.2991	0.2759	0.5350	0.042*
H3B	0.2934	0.4979	0.5406	0.042*
C1	0.1381 (11)	0.2748 (10)	0.8819 (10)	0.0428 (15)
H1B	0.2564	0.1808	0.8788	0.064*
H1C	0.0342	0.2098	0.9796	0.064*
H1D	0.1872	0.3869	0.9129	0.064*
Br1	0.61718 (10)	0.21220 (10)	0.19573 (10)	0.0445 (3)
O1	0.7864 (11)	0.0695 (11)	0.6378 (10)	0.0737 (19)
H1WA	0.675 (9)	0.027 (18)	0.707 (10)	0.11 (5)*
H1WB	0.757 (12)	0.090 (12)	0.519 (4)	0.05 (2)*

Atomic displacement parameters (Å²)

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.035 (3)	0.031 (2)	0.028 (3)	−0.003 (2)	−0.002 (2)	−0.007 (2)
C2	0.037 (3)	0.043 (3)	0.027 (3)	0.001 (3)	0.002 (2)	−0.012 (3)
C3	0.031 (3)	0.041 (3)	0.031 (3)	0.003 (2)	−0.001 (2)	−0.013 (3)
C1	0.056 (4)	0.043 (4)	0.028 (3)	0.000 (3)	−0.010 (3)	−0.008 (3)
Br1	0.0393 (4)	0.0481 (5)	0.0451 (5)	−0.0090 (3)	−0.0021 (3)	−0.0116 (3)
O1	0.080 (4)	0.084 (4)	0.055 (4)	−0.048 (4)	−0.012 (3)	−0.007 (3)

Geometric parameters (Å, º)

N1—C1	1.482 (8)	C3—H3A	0.9700
N1—C3	1.498 (8)	C3—H3B	0.9700
N1—C2	1.516 (8)	C1—H1B	0.9600
N1—H1A	0.9100	C1—H1C	0.9600
C2—C3ⁱ	1.497 (9)	C1—H1D	0.9600
C2—H2A	0.9700	O1—H1WA	0.853 (10)
C2—H2B	0.9700	O1—H1WB	0.854 (10)
C3—C2ⁱ	1.497 (9)

C1—N1—C3	111.3 (5)	N1—C3—H3A	109.2
C1—N1—C2	111.1 (5)	C2ⁱ—C3—H3A	109.2
C3—N1—C2	109.7 (5)	N1—C3—H3B	109.2
C1—N1—H1A	108.2	C2ⁱ—C3—H3B	109.2
C3—N1—H1A	108.2	H3A—C3—H3B	107.9
C2—N1—H1A	108.2	N1—C1—H1B	109.5
C3ⁱ—C2—N1	110.7 (5)	N1—C1—H1C	109.5
C3ⁱ—C2—H2A	109.5	H1B—C1—H1C	109.5
N1—C2—H2A	109.5	N1—C1—H1D	109.5
C3ⁱ—C2—H2B	109.5	H1B—C1—H1D	109.5
N1—C2—H2B	109.5	H1C—C1—H1D	109.5
H2A—C2—H2B	108.1	H1WA—O1—H1WB	107 (3)
N1—C3—C2ⁱ	111.9 (5)

C1—N1—C2—C3ⁱ	179.4 (5)	C1—N1—C3—C2ⁱ	180.0 (5)
C3—N1—C2—C3ⁱ	56.0 (7)	C2—N1—C3—C2ⁱ	−56.7 (7)

Symmetry code: (i) −x, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O1ⁱⁱ	0.91	1.83	2.737 (9)	174
O1—H1WA···Br1ⁱⁱⁱ	0.85 (6)	2.51 (9)	3.275 (7)	151 (11)
O1—H1WB···Br1	0.85 (3)	2.41 (4)	3.244 (7)	166 (7)

Symmetry codes: (ii) x−1, y, z; (iii) −x+1, −y, −z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HB6759).

References

Fu, D.-W., Ge, J.-Z., Dai, J., Ye, H.-Y. & Qu, Z.-R. (2009). Inorg. Chem. Commun. 12, 994–997.
Rigaku (2005). CrystalClear Rigaku Corporation, Tokyo, Japan .
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]

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