N,N′-[1,4-Phenyl­enebis(methyl­ene)]bis­(N,N-diethyl­ethanaminium) dibromide

Abdul Rahim, M.S.; Khaledi, H.; Alias, Y.; Welz-Biermann, U.

doi:10.1107/S1600536812000141

organic compounds

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Volume 68| Part 2| February 2012| Page o369

doi:10.1107/S1600536812000141

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N,N′-[1,4-Phenylenebis(methylene)]bis(N,N-diethylethanaminium) dibromide

Munirah Sufiyah Abdul Rahim,^a Hamid Khaledi,^b ^* Yatimah Alias ^a and Urs Welz-Biermann ^c

^aUniversity of Malaya Centre for Ionic Liquids, Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, ^bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, and ^cChina Ionic Liquid Laboratory, Dalian Institute of Chemical Physics, Chinese, Academy of Sciences, 116023 Dalian, People's Republic of China
^*Correspondence e-mail: khaledi@siswa.um.edu.my

(Received 28 December 2011; accepted 3 January 2012; online 11 January 2012)

In the crystal structure of the title compound, C₂₀H₃₈N₂²⁺·2Br⁻, the centroid of the aromatic ring is located on an inversion center, so that the asymmetric unit consists of one-half molecule of the dication and one bromide anion. C—H⋯Br interactions connect the two components into a three-dimensional network. An intramolecular C—H⋯π interaction is also observed.

Related literature

For the properties of dicationic ionic liquids, see: Anderson et al. (2005 ). For the structure of p-phenylenedimethanaminium dibromide, see: Zhang & Han (2010 ).

Experimental

Crystal data

C₂₀H₃₈N₂²⁺·2Br⁻
M_r = 466.34
Monoclinic, P 2₁ /n
a = 8.2713 (5) Å
b = 14.1440 (9) Å
c = 9.0762 (6) Å
β = 97.634 (1)°
V = 1052.41 (12) Å³
Z = 2
Mo Kα radiation
μ = 3.86 mm⁻¹
T = 100 K
0.51 × 0.47 × 0.35 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.244, T_max = 0.346
10066 measured reflections
2304 independent reflections
2093 reflections with I > 2σ(I)
R_int = 0.021

Refinement

R[F² > 2σ(F²)] = 0.017
wR(F²) = 0.043
S = 1.06
2304 reflections
112 parameters
H-atom parameters constrained
Δρ_max = 0.43 e Å⁻³
Δρ_min = −0.23 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the aromatic ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C7—H7A⋯Br1	0.99	2.80	3.7565 (14)	163
C2—H2B⋯Br1ⁱ	0.99	2.90	3.7716 (14)	148
C6—H6B⋯Br1ⁱⁱ	0.99	2.92	3.8318 (14)	153
C7—H7B⋯Br1ⁱⁱ	0.99	2.89	3.7832 (14)	150
C1—H1C⋯Cg	0.98	2.74	3.6529 (16)	156
Symmetry codes: (i) x, y, z+1; (ii) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001 ); software used to prepare material for publication: SHELXL97 and publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812000141/is5042sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812000141/is5042Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812000141/is5042Isup3.cml

checkCIF report

Comment top

In comparison to the common singly charged ionic liquids, dicationic ionic liquids are a new class of organic salts having two positive charges on the same cation. They have been proved to have a better performance in terms of thermal stability, wide liquidus range, and unusual dissolution properties (Anderson et al., 2005). The title compound was synthesized as a precursor for the synthesis of dicationic ionic liquids with a rigid phenylene group spacer.

Similar to the structure of p-phenylenedimethanaminium dibromide (Zhang & Han, 2010), the centroid of the aromatic ring is located on an inversion center, therefore the asymmetric unit consists of one-half of the dication and one bromide anion. In the crystal, the cations and anions are linked into a three-dimensional polymeric structure via C—H···Br interactions. The network is further condolidated by intramolecular C—H···π interactions (Table 1).

Related literature top

For the properties of dicationic ionic liquids, see: Anderson et al. (2005). For the structure of p-phenylenedimethanaminium dibromide, see: Zhang & Han (2010).

Experimental top

Triethylamine (3.06 ml, 22 mmol) was added dropwise to a solution of α,α-dibromo-p-xylene (2.64 g, 10 mmol) in acetonitrile (50 ml). The mixture was stirred at room temperature for 24 hr. The white precipitate of the product was filtered and washed with acetonitrile and dried under vacuum. Recrystallization of the dicationic salt from methanol afforded crystals suitable for X-ray crystallographicanalysis

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and publCIF (Westrip, 2010).

Figures top

Fig. 1. Molecular structure of the title compound with displacement ellipsoids drawn at 50% probability level. Hydrogen atoms are drawn as spheres of arbitrary radius. [Symmetry code: ' = -x + 1, -y + 1, -z + 1.]

N,N'-[1,4-Phenylenebis(methylene)]bis(N,N- diethylethanaminium) dibromide top

Crystal data top

C₂₀H₃₈N₂²⁺·2Br⁻	F(000) = 484
M_r = 466.34	D_x = 1.472 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 8155 reflections
a = 8.2713 (5) Å	θ = 2.7–28.3°
b = 14.1440 (9) Å	µ = 3.86 mm⁻¹
c = 9.0762 (6) Å	T = 100 K
β = 97.634 (1)°	Block, colorless
V = 1052.41 (12) Å³	0.51 × 0.47 × 0.35 mm
Z = 2

Data collection top

Bruker APEXII CCD diffractometer	2304 independent reflections
Radiation source: fine-focus sealed tube	2093 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.021
ϕ and ω scans	θ_max = 27.0°, θ_min = 2.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −10→10
T_min = 0.244, T_max = 0.346	k = −16→18
10066 measured reflections	l = −11→11

Refinement top

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)] = 0.017	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.043	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.019P)² + 0.5002P] where P = (F_o² + 2F_c²)/3
2304 reflections	(Δ/σ)_max = 0.001
112 parameters	Δρ_max = 0.43 e Å⁻³
0 restraints	Δρ_min = −0.23 e Å⁻³

Crystal data top

C₂₀H₃₈N₂²⁺·2Br⁻	V = 1052.41 (12) Å³
M_r = 466.34	Z = 2
Monoclinic, P2₁/n	Mo Kα radiation
a = 8.2713 (5) Å	µ = 3.86 mm⁻¹
b = 14.1440 (9) Å	T = 100 K
c = 9.0762 (6) Å	0.51 × 0.47 × 0.35 mm
β = 97.634 (1)°

Data collection top

Bruker APEXII CCD diffractometer	2304 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2093 reflections with I > 2σ(I)
T_min = 0.244, T_max = 0.346	R_int = 0.021
10066 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.017	0 restraints
wR(F²) = 0.043	H-atom parameters constrained
S = 1.06	Δρ_max = 0.43 e Å⁻³
2304 reflections	Δρ_min = −0.23 e Å⁻³
112 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

	x	y	z	U_iso*/U_eq
N1	0.82236 (14)	0.33100 (8)	0.70235 (13)	0.0099 (2)
C1	0.72184 (18)	0.46030 (11)	0.87038 (16)	0.0176 (3)
H1A	0.8299	0.4897	0.8894	0.026*
H1B	0.6651	0.4681	0.9578	0.026*
H1C	0.6585	0.4906	0.7843	0.026*
C2	0.74049 (18)	0.35590 (10)	0.83906 (15)	0.0138 (3)
H2A	0.6308	0.3267	0.8271	0.017*
H2B	0.8045	0.3266	0.9273	0.017*
C3	1.10397 (18)	0.38839 (11)	0.80909 (16)	0.0156 (3)
H3A	1.0615	0.3870	0.9049	0.023*
H3B	1.1769	0.4428	0.8062	0.023*
H3C	1.1644	0.3300	0.7967	0.023*
C4	0.96263 (16)	0.39682 (10)	0.68396 (15)	0.0120 (3)
H4A	0.9223	0.4628	0.6796	0.014*
H4B	1.0028	0.3828	0.5883	0.014*
C5	0.97084 (18)	0.18930 (11)	0.60528 (17)	0.0166 (3)
H5A	0.8954	0.1845	0.5127	0.025*
H5B	1.0132	0.1264	0.6346	0.025*
H5C	1.0616	0.2311	0.5900	0.025*
C6	0.88154 (17)	0.22941 (10)	0.72681 (16)	0.0131 (3)
H6A	0.9550	0.2263	0.8221	0.016*
H6B	0.7862	0.1887	0.7364	0.016*
C7	0.69822 (17)	0.33096 (10)	0.56112 (15)	0.0113 (3)
H7A	0.7577	0.3197	0.4750	0.014*
H7B	0.6231	0.2770	0.5668	0.014*
C8	0.59739 (16)	0.41916 (10)	0.53110 (15)	0.0110 (3)
C9	0.43874 (17)	0.42236 (10)	0.56832 (15)	0.0124 (3)
H9	0.3958	0.3692	0.6139	0.015*
C10	0.65646 (17)	0.49722 (10)	0.46095 (15)	0.0126 (3)
H10	0.7630	0.4954	0.4329	0.015*
Br1	0.937757 (16)	0.344754 (10)	0.237945 (15)	0.01420 (6)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0107 (5)	0.0084 (6)	0.0103 (5)	0.0003 (5)	−0.0002 (4)	0.0017 (4)
C1	0.0219 (7)	0.0177 (8)	0.0136 (7)	0.0005 (6)	0.0034 (6)	−0.0040 (6)
C2	0.0152 (7)	0.0164 (7)	0.0102 (6)	−0.0006 (6)	0.0035 (5)	−0.0001 (5)
C3	0.0136 (7)	0.0160 (8)	0.0162 (7)	−0.0026 (6)	−0.0022 (5)	0.0011 (6)
C4	0.0126 (6)	0.0107 (7)	0.0126 (6)	−0.0029 (5)	0.0009 (5)	0.0008 (5)
C5	0.0162 (7)	0.0118 (7)	0.0212 (7)	0.0033 (6)	0.0005 (6)	−0.0012 (6)
C6	0.0137 (6)	0.0089 (7)	0.0160 (7)	0.0011 (6)	−0.0007 (5)	0.0034 (6)
C7	0.0111 (6)	0.0112 (7)	0.0108 (6)	−0.0007 (5)	−0.0020 (5)	−0.0008 (5)
C8	0.0122 (6)	0.0105 (7)	0.0095 (6)	0.0009 (5)	−0.0017 (5)	−0.0005 (5)
C9	0.0132 (6)	0.0115 (7)	0.0124 (6)	−0.0013 (5)	0.0011 (5)	0.0029 (5)
C10	0.0106 (6)	0.0149 (7)	0.0121 (6)	0.0001 (5)	0.0012 (5)	0.0006 (5)
Br1	0.01526 (8)	0.01314 (8)	0.01435 (8)	0.00247 (5)	0.00246 (5)	0.00042 (5)

Geometric parameters (Å, º) top

N1—C4	1.5140 (17)	C5—C6	1.517 (2)
N1—C6	1.5246 (18)	C5—H5A	0.9800
N1—C2	1.5314 (17)	C5—H5B	0.9800
N1—C7	1.5322 (17)	C5—H5C	0.9800
C1—C2	1.516 (2)	C6—H6A	0.9900
C1—H1A	0.9800	C6—H6B	0.9900
C1—H1B	0.9800	C7—C8	1.5052 (19)
C1—H1C	0.9800	C7—H7A	0.9900
C2—H2A	0.9900	C7—H7B	0.9900
C2—H2B	0.9900	C8—C10	1.395 (2)
C3—C4	1.5225 (19)	C8—C9	1.3986 (19)
C3—H3A	0.9800	C9—C10ⁱ	1.389 (2)
C3—H3B	0.9800	C9—H9	0.9500
C3—H3C	0.9800	C10—C9ⁱ	1.389 (2)
C4—H4A	0.9900	C10—H10	0.9500
C4—H4B	0.9900

C4—N1—C6	111.08 (10)	H4A—C4—H4B	107.8
C4—N1—C2	112.07 (11)	C6—C5—H5A	109.5
C6—N1—C2	105.47 (10)	C6—C5—H5B	109.5
C4—N1—C7	110.25 (10)	H5A—C5—H5B	109.5
C6—N1—C7	106.74 (10)	C6—C5—H5C	109.5
C2—N1—C7	111.01 (10)	H5A—C5—H5C	109.5
C2—C1—H1A	109.5	H5B—C5—H5C	109.5
C2—C1—H1B	109.5	C5—C6—N1	115.13 (12)
H1A—C1—H1B	109.5	C5—C6—H6A	108.5
C2—C1—H1C	109.5	N1—C6—H6A	108.5
H1A—C1—H1C	109.5	C5—C6—H6B	108.5
H1B—C1—H1C	109.5	N1—C6—H6B	108.5
C1—C2—N1	116.30 (12)	H6A—C6—H6B	107.5
C1—C2—H2A	108.2	C8—C7—N1	116.41 (11)
N1—C2—H2A	108.2	C8—C7—H7A	108.2
C1—C2—H2B	108.2	N1—C7—H7A	108.2
N1—C2—H2B	108.2	C8—C7—H7B	108.2
H2A—C2—H2B	107.4	N1—C7—H7B	108.2
C4—C3—H3A	109.5	H7A—C7—H7B	107.3
C4—C3—H3B	109.5	C10—C8—C9	118.77 (13)
H3A—C3—H3B	109.5	C10—C8—C7	121.29 (12)
C4—C3—H3C	109.5	C9—C8—C7	119.88 (13)
H3A—C3—H3C	109.5	C10ⁱ—C9—C8	120.44 (13)
H3B—C3—H3C	109.5	C10ⁱ—C9—H9	119.8
N1—C4—C3	113.17 (11)	C8—C9—H9	119.8
N1—C4—H4A	108.9	C9ⁱ—C10—C8	120.76 (13)
C3—C4—H4A	108.9	C9ⁱ—C10—H10	119.6
N1—C4—H4B	108.9	C8—C10—H10	119.6
C3—C4—H4B	108.9

Symmetry code: (i) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, º) top

Cg is the centroid of the aromatic ring.

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7A···Br1	0.99	2.80	3.7565 (14)	163
C2—H2B···Br1ⁱⁱ	0.99	2.90	3.7716 (14)	148
C6—H6B···Br1ⁱⁱⁱ	0.99	2.92	3.8318 (14)	153
C7—H7B···Br1ⁱⁱⁱ	0.99	2.89	3.7832 (14)	150
C1—H1C···Cg	0.98	2.74	3.6529 (16)	156

Symmetry codes: (ii) x, y, z+1; (iii) x−1/2, −y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formula	C₂₀H₃₈N₂²⁺·2Br⁻
M_r	466.34
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	100
a, b, c (Å)	8.2713 (5), 14.1440 (9), 9.0762 (6)
β (°)	97.634 (1)
V (Å³)	1052.41 (12)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	3.86
Crystal size (mm)	0.51 × 0.47 × 0.35

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.244, 0.346
No. of measured, independent and observed [I > 2σ(I)] reflections	10066, 2304, 2093
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.017, 0.043, 1.06
No. of reflections	2304
No. of parameters	112
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.43, −0.23

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), X-SEED (Barbour, 2001), SHELXL97 (Sheldrick, 2008) and publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top

Cg is the centroid of the aromatic ring.

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7A···Br1	0.99	2.80	3.7565 (14)	163.3
C2—H2B···Br1ⁱ	0.99	2.90	3.7716 (14)	147.5
C6—H6B···Br1ⁱⁱ	0.99	2.92	3.8318 (14)	153.2
C7—H7B···Br1ⁱⁱ	0.99	2.89	3.7832 (14)	150.3
C1—H1C···Cg	0.98	2.74	3.6529 (16)	156

Symmetry codes: (i) x, y, z+1; (ii) x−1/2, −y+1/2, z+1/2.

Acknowledgements

The authors acknowledge the University of Malaya for financial support (HIR-MOHE F00004–21001).

References

Anderson, J. L., Rongfang, D., Ellern, A. & Armstrong, D. W. (2005). J. Am. Chem. Soc. 127, 593–604. Web of Science CSD CrossRef PubMed CAS Google Scholar
Barbour, L. J. (2001). J. Supramol. Chem. 1, 189–191. CrossRef CAS Google Scholar
Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920–925. Web of Science CrossRef CAS IUCr Journals Google Scholar
Zhang, Y. & Han, M. T. (2010). Acta Cryst. E66, o1865. Web of Science CSD CrossRef IUCr Journals Google Scholar

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CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 68| Part 2| February 2012| Page o369

doi:10.1107/S1600536812000141

Open

access