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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 69| Part 11| November 2013| Page o1606
doi:10.1107/S1600536813026810

4-[2-(Pyridin-1-ium-4-yl)eth­yl]pyridin-1-ium bis­­(2,6-di­nitro­benzoate)

Hadi D. Arman,a Tyler Millera and Edward R. T. Tiekinkb*

aDepartment of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-0698, USA, and bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: edward.tiekink@gmail.com

(Received 30 September 2013; accepted 30 September 2013; online 2 October 2013)

The asymmetric unit of the title salt, C12H14N22+·2C7H3N2O6−, comprises half a 4-[2-(pyridin-1-ium-4-yl)eth­yl]pyridin-1-ium dication, being disposed about a centre of inversion, and a 2,6-di­nitro­benzoate anion, in a general position. In the anion, the carboxyl­ate group is inclined to the benzene ring [dihedral angle = 85.45 (9)°], whereas near-coplanar and twisted arrangements are found for the nitro groups [O—N—C—C torsion angles = 179.80 (14) and 20.2 (2)°]. In the crystal, three-component aggregates sustained by charge-assisted N+—H⋯O− hydrogen bonds are found and these are consolidated into a three-dimensional architecture by C—H⋯O and π–π [inter-centroid distances = 3.6796 (14) and 3.7064 (14) Å] inter­actions.

CCDC reference: 963645

Related literature

For the 2:1 salts of 2,6-di­nitro­benzoate with isomeric n-({[(pyri­din-1-ium-n-ylmeth­yl)carbamo­yl]formamido}­meth­yl)pyridin-1-ium, n = 2, 3 and 4, and for the structure of 2,6-di­nitro­benzoic acid, see: Arman et al. (2013[Arman, H. D., Miller, T. & Tiekink, E. R. T. (2013). Z. Kristallogr. Cryst. Mat. 228, 295-303.]).

[Scheme 1]

Experimental

Crystal data

  • 0.5C12H14N22+·C7H3N2O6−

  • Mr = 304.24

  • Triclinic, [P \overline 1]

  • a = 6.6916 (12) Å

  • b = 8.3690 (17) Å

  • c = 12.358 (3) Å

  • α = 88.809 (12)°

  • β = 76.322 (8)°

  • γ = 72.193 (9)°

  • V = 639.2 (2) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.13 mm−1

  • T = 98 K

  • 0.36 × 0.12 × 0.07 mm
Data collection

  • Rigaku AFC12/SATURN724 diffractometer

  • 4421 measured reflections

  • 2915 independent reflections

  • 2538 reflections with I > 2σ(I)

  • Rint = 0.035
Refinement

  • R[F2 > 2σ(F2)] = 0.050

  • wR(F2) = 0.124

  • S = 1.07

  • 2915 reflections

  • 202 parameters

  • 1 restraint

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.33 e Å−3

  • Δρmin = −0.28 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N3—H3n⋯O1 0.90 (1) 1.64 (2) 2.5240 (19) 166 (2)
C8—H8⋯O6i 0.95 2.50 3.436 (2) 169
C11—H11⋯O2ii 0.95 2.52 3.377 (2) 150
C12—H12⋯O4iii 0.95 2.46 3.118 (2) 126
Symmetry codes: (i) -x+1, -y, -z+1; (ii) x-1, y+1, z; (iii) -x+1, -y+1, -z.

Data collection: CrystalClear (Molecular Structure Corporation & Rigaku, 2005[Molecular Structure Corporation & Rigaku (2005). CrystalClear. MSC, The Woodlands, Texas, USA, and 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: ORTEPII (Johnson, 1976[Johnson, C. K. (1976). ORTEPII. Report ORNL-5138. Oak Ridge National Laboratory, Tennessee, USA.]) and DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information

CCDC reference: 963645

Crystal structure: contains datablocks general, I. DOI: 10.1107/S1600536813026810/hg5351sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813026810/hg5351Isup2.hkl

checkCIF report


Comment top

The title salt, (I), was isolated as part of studies investigating the co-crystallization of 2,6-dinitrobenzoic acid and different pyridyl derivatives (Arman et al., 2013).

The asymmetric unit of (I) comprises half of a 4-[2-(pyridin-1-ium-4-yl)ethyl]pyridin-1-ium dication, disposed about a centre of inversion, and a 2,6-dinitrobenzoate anion, Fig. 1. A kink about the ethylene bridge is evident in the dication with the C9—C10—C13—C13i torsion angle being 104.1 (2)° [symmetry operation i: -x, 2 - y, 1 - z]. In the anion, the carboxylate is inclined to the benzene ring to which it is attached forming a dihedral angle of 85.45 (9)°, as is seen in the structures of related compounds, including that of 2,6-dinitrobenzoic acid (Arman et al., 2013). One nitro group is co-planar and the other twisted out of the plane of the benzene ring to which they are attached, forming O3—N2—C2—C3 and O5—N1—C6—C5 torsion angles of 179.80 (14) and 20.2 (2)°. respectively.

The ions are connected into three-component aggregates by charge-assisted N—H···O hydrogen bonds, Table 1. These are connected by C—H···O and π—π [inter-centroid distance for centrosymmetrically related pyridinium rings = 3.6796 (14) Å for symmetry operation -x, 1 - y, 1 - z, and for centrosymmetrically related benzene rings = 3.7064 (14) Å for 1 - x, -y, -z] interactions into a three-dimensional architecture, Fig. 2.

Related literature top

For the 2:1 salts of 2,6-dinitrobenzoate with isomeric n-({[(pyridin-1-ium-n-ylmethyl)carbamoyl]formamido}methyl)pyridin-1-ium, n = 2, 3 and 4, and for the structure of 2,6-dinitrobenzoic acid, see: Arman et al. (2013).

Experimental top

Crystals of (I) were obtained by the co-crystallization of 4,4'-bipyridylethane (Sigma Aldrich, 0.11 mmol) and 2,6-dinitrobenzoic acid (Sigma-Aldrich, 0.22 mmol) in methanol solution. Colourless crystals were obtained by slow evaporation. Melting point: 425–431 K. IR spectra (cm-1): 744(w), 849(s)(sh), 915(m), 1340(m), 1505(m), 1529(s), 1628(m)(sh), 1673(w), 3086(w)(br).

Refinement top

The C-bound H-atoms were placed in calculated positions (C—H = 0.95–0.99 Å) and were included in the refinement in the riding model approximation with Uiso(H) set to 1.2Ueq(C). The N-bound H-atom was located in a difference Fourier map and refined with a distance restraint of N—H = 0.88±0.01 Å, and with Uiso(H) = 1.2Ueq(N).

Computing details top

Data collection: CrystalClear (Molecular Structure Corporation & Rigaku, 2005); cell refinement: CrystalClear (Molecular Structure Corporation & Rigaku, 2005); data reduction: CrystalClear (Molecular Structure Corporation & Rigaku, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPII (Johnson, 1976) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. Molecular structures of the components of (I), showing atom-labelling scheme and displacement ellipsoids at the 70% probability level: (a) the 2,6-dinitrobenzoate anion, and (b) the 4-[2-(pyridin-1-ium-4-yl)ethyl]pyridin-1-ium dication (unlabelled atoms are related by the symmetry operation -x, 2 - y, 1-z).
[Figure 2] Fig. 2. Unit-cell contents in (I) viewed down the b axis. The N—H···O, C—H···O and π—π interactions are shown as orange, blue and purple dashed lines, respectively.
4-[2-(Pyridin-1-ium-4-yl)ethyl]pyridin-1-ium bis(2,6-dinitrobenzoate) top
Crystal data top
0.5C12H14N22+·C7H3N2O6−Z = 2
Mr = 304.24F(000) = 314
Triclinic, P1Dx = 1.581 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71069 Å
a = 6.6916 (12) ÅCell parameters from 3299 reflections
b = 8.3690 (17) Åθ = 3.0–40.2°
c = 12.358 (3) ŵ = 0.13 mm−1
α = 88.809 (12)°T = 98 K
β = 76.322 (8)°Chip, colourless
γ = 72.193 (9)°0.36 × 0.12 × 0.07 mm
V = 639.2 (2) Å3
Data collection top
Rigaku AFC12K/SATURN724
diffractometer		2538 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.035
Graphite monochromatorθmax = 27.5°, θmin = 3.0°
ω scansh = −8→7
4421 measured reflectionsk = −10→8
2915 independent reflectionsl = −15→16
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.050Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.124H atoms treated by a mixture of independent and constrained refinement
S = 1.07 w = 1/[σ2(Fo2) + (0.0536P)2 + 0.3505P]
where P = (Fo2 + 2Fc2)/3
2915 reflections(Δ/σ)max < 0.001
202 parametersΔρmax = 0.33 e Å−3
1 restraintΔρmin = −0.28 e Å−3
Crystal data top
0.5C12H14N22+·C7H3N2O6−γ = 72.193 (9)°
Mr = 304.24V = 639.2 (2) Å3
Triclinic, P1Z = 2
a = 6.6916 (12) ÅMo Kα radiation
b = 8.3690 (17) ŵ = 0.13 mm−1
c = 12.358 (3) ÅT = 98 K
α = 88.809 (12)°0.36 × 0.12 × 0.07 mm
β = 76.322 (8)°
Data collection top
Rigaku AFC12K/SATURN724
diffractometer		2538 reflections with I > 2σ(I)
4421 measured reflectionsRint = 0.035
2915 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0501 restraint
wR(F2) = 0.124H atoms treated by a mixture of independent and constrained refinement
S = 1.07Δρmax = 0.33 e Å−3
2915 reflectionsΔρmin = −0.28 e Å−3
202 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
O10.43537 (19)0.16380 (14)0.27124 (10)0.0207 (3)
O20.7856 (2)0.08627 (15)0.27881 (10)0.0230 (3)
O30.6692 (2)0.30495 (15)0.09243 (11)0.0275 (3)
O40.7613 (2)0.25616 (17)−0.08566 (11)0.0323 (3)
O50.7607 (3)−0.43097 (15)0.24069 (12)0.0352 (4)
O60.5746 (2)−0.18948 (16)0.32479 (11)0.0304 (3)
N10.6805 (2)−0.27800 (17)0.24086 (12)0.0210 (3)
N20.7206 (2)0.21045 (17)0.00970 (12)0.0185 (3)
C10.6929 (2)−0.02772 (19)0.13148 (13)0.0158 (3)
C20.7358 (2)0.03113 (19)0.02412 (13)0.0163 (3)
C30.7944 (3)−0.0701 (2)−0.07317 (14)0.0193 (3)
H30.8218−0.0241−0.14410.023*
C40.8122 (3)−0.2389 (2)−0.06528 (14)0.0222 (4)
H40.8515−0.3095−0.13100.027*
C50.7727 (3)−0.3049 (2)0.03835 (14)0.0204 (3)
H50.7844−0.42060.04450.024*
C60.7156 (3)−0.19921 (19)0.13322 (14)0.0172 (3)
C70.6353 (3)0.08483 (19)0.23831 (13)0.0168 (3)
N30.3059 (2)0.44597 (17)0.37677 (12)0.0181 (3)
H3N0.369 (3)0.3421 (15)0.3443 (16)0.022*
C80.2755 (3)0.4803 (2)0.48557 (14)0.0186 (3)
H80.33490.39420.53080.022*
C90.1587 (3)0.63957 (19)0.53319 (13)0.0182 (3)
H90.14020.66350.61040.022*
C100.0682 (3)0.76502 (19)0.46686 (14)0.0177 (3)
C110.1067 (3)0.7261 (2)0.35320 (14)0.0185 (3)
H110.05010.80960.30570.022*
C120.2273 (3)0.5659 (2)0.31021 (14)0.0193 (3)
H120.25530.53980.23260.023*
C13−0.0661 (3)0.93814 (19)0.51519 (14)0.0197 (3)
H13A−0.11240.93620.59730.024*
H13B−0.19720.97590.48570.024*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0211 (6)0.0170 (6)0.0209 (6)−0.0035 (4)−0.0020 (5)−0.0026 (4)
O20.0256 (6)0.0242 (6)0.0202 (6)−0.0065 (5)−0.0090 (5)−0.0016 (5)
O30.0425 (8)0.0181 (6)0.0238 (7)−0.0123 (5)−0.0075 (6)0.0014 (5)
O40.0449 (8)0.0296 (7)0.0206 (7)−0.0132 (6)−0.0033 (6)0.0102 (5)
O50.0588 (10)0.0139 (6)0.0325 (8)−0.0068 (6)−0.0161 (7)0.0047 (5)
O60.0387 (8)0.0234 (7)0.0198 (7)−0.0035 (6)0.0027 (5)0.0028 (5)
N10.0243 (7)0.0168 (7)0.0233 (8)−0.0067 (5)−0.0079 (6)0.0035 (5)
N20.0172 (7)0.0192 (7)0.0194 (7)−0.0068 (5)−0.0038 (5)0.0045 (5)
C10.0135 (7)0.0161 (7)0.0168 (8)−0.0035 (6)−0.0030 (6)0.0002 (6)
C20.0146 (7)0.0164 (7)0.0181 (8)−0.0049 (6)−0.0043 (6)0.0026 (6)
C30.0160 (7)0.0251 (8)0.0153 (8)−0.0051 (6)−0.0026 (6)0.0004 (6)
C40.0191 (8)0.0262 (9)0.0194 (8)−0.0043 (7)−0.0039 (6)−0.0066 (6)
C50.0192 (8)0.0162 (7)0.0248 (9)−0.0036 (6)−0.0058 (6)−0.0031 (6)
C60.0160 (7)0.0160 (7)0.0198 (8)−0.0047 (6)−0.0051 (6)0.0019 (6)
C70.0225 (8)0.0127 (7)0.0144 (7)−0.0055 (6)−0.0027 (6)0.0018 (5)
N30.0176 (7)0.0151 (6)0.0201 (7)−0.0050 (5)−0.0017 (5)0.0002 (5)
C80.0190 (8)0.0171 (8)0.0200 (8)−0.0067 (6)−0.0039 (6)0.0035 (6)
C90.0217 (8)0.0186 (8)0.0145 (7)−0.0081 (6)−0.0027 (6)0.0015 (6)
C100.0175 (7)0.0159 (7)0.0201 (8)−0.0080 (6)−0.0017 (6)0.0006 (6)
C110.0218 (8)0.0165 (7)0.0178 (8)−0.0066 (6)−0.0052 (6)0.0029 (6)
C120.0229 (8)0.0183 (8)0.0165 (8)−0.0070 (6)−0.0035 (6)0.0011 (6)
C130.0217 (8)0.0147 (7)0.0205 (8)−0.0061 (6)−0.0001 (6)−0.0012 (6)
Geometric parameters (Å, º) top
O1—C71.267 (2)C5—H50.9500
O2—C71.228 (2)N3—C81.335 (2)
O3—N21.2206 (18)N3—C121.345 (2)
O4—N21.2258 (19)N3—H3N0.897 (9)
O5—N11.2273 (19)C8—C91.383 (2)
O6—N11.2207 (19)C8—H80.9500
N1—C61.473 (2)C9—C101.397 (2)
N2—C21.483 (2)C9—H90.9500
C1—C61.397 (2)C10—C111.394 (2)
C1—C21.402 (2)C10—C131.500 (2)
C1—C71.539 (2)C11—C121.377 (2)
C2—C31.391 (2)C11—H110.9500
C3—C41.384 (2)C12—H120.9500
C3—H30.9500C13—C13i1.543 (3)
C4—C51.384 (2)C13—H13A0.9900
C4—H40.9500C13—H13B0.9900
C5—C61.388 (2)
O6—N1—O5123.53 (15)O1—C7—C1113.71 (14)
O6—N1—C6119.05 (14)C8—N3—C12120.98 (14)
O5—N1—C6117.43 (14)C8—N3—H3N123.2 (13)
O3—N2—O4123.22 (14)C12—N3—H3N115.6 (13)
O3—N2—C2118.95 (13)N3—C8—C9120.80 (15)
O4—N2—C2117.82 (14)N3—C8—H8119.6
C6—C1—C2114.17 (14)C9—C8—H8119.6
C6—C1—C7122.75 (14)C8—C9—C10119.46 (15)
C2—C1—C7123.03 (14)C8—C9—H9120.3
C3—C2—C1123.70 (15)C10—C9—H9120.3
C3—C2—N2116.29 (14)C11—C10—C9118.29 (15)
C1—C2—N2120.01 (14)C11—C10—C13120.17 (15)
C4—C3—C2119.06 (15)C9—C10—C13121.55 (15)
C4—C3—H3120.5C12—C11—C10119.58 (15)
C2—C3—H3120.5C12—C11—H11120.2
C5—C4—C3120.03 (15)C10—C11—H11120.2
C5—C4—H4120.0N3—C12—C11120.82 (15)
C3—C4—H4120.0N3—C12—H12119.6
C4—C5—C6118.91 (15)C11—C12—H12119.6
C4—C5—H5120.5C10—C13—C13i110.09 (16)
C6—C5—H5120.5C10—C13—H13A109.6
C5—C6—C1124.13 (15)C13i—C13—H13A109.6
C5—C6—N1116.20 (14)C10—C13—H13B109.6
C1—C6—N1119.67 (14)C13i—C13—H13B109.6
O2—C7—O1129.53 (15)H13A—C13—H13B108.2
O2—C7—C1116.76 (14)
C6—C1—C2—C30.5 (2)O6—N1—C6—C5−159.79 (16)
C7—C1—C2—C3178.01 (14)O5—N1—C6—C520.2 (2)
C6—C1—C2—N2−179.28 (13)O6—N1—C6—C120.9 (2)
C7—C1—C2—N2−1.7 (2)O5—N1—C6—C1−159.13 (16)
O3—N2—C2—C3179.80 (14)C6—C1—C7—O284.16 (19)
O4—N2—C2—C3−0.4 (2)C2—C1—C7—O2−93.16 (19)
O3—N2—C2—C1−0.4 (2)C6—C1—C7—O1−96.06 (18)
O4—N2—C2—C1179.36 (15)C2—C1—C7—O186.61 (19)
C1—C2—C3—C40.0 (2)C12—N3—C8—C91.2 (2)
N2—C2—C3—C4179.77 (14)N3—C8—C9—C101.2 (2)
C2—C3—C4—C5−0.2 (2)C8—C9—C10—C11−2.5 (2)
C3—C4—C5—C6−0.1 (3)C8—C9—C10—C13177.92 (14)
C4—C5—C6—C10.6 (3)C9—C10—C11—C121.5 (2)
C4—C5—C6—N1−178.67 (15)C13—C10—C11—C12−178.94 (15)
C2—C1—C6—C5−0.8 (2)C8—N3—C12—C11−2.3 (2)
C7—C1—C6—C5−178.33 (15)C10—C11—C12—N30.9 (2)
C2—C1—C6—N1178.46 (14)C11—C10—C13—C13i−75.5 (2)
C7—C1—C6—N10.9 (2)C9—C10—C13—C13i104.1 (2)
Symmetry code: (i) −x, −y+2, −z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3n···O10.90 (1)1.64 (2)2.5240 (19)166 (2)
C8—H8···O6ii0.952.503.436 (2)169
C11—H11···O2iii0.952.523.377 (2)150
C12—H12···O4iv0.952.463.118 (2)126
Symmetry codes: (ii) −x+1, −y, −z+1; (iii) x−1, y+1, z; (iv) −x+1, −y+1, −z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3n···O10.897 (14)1.643 (15)2.5240 (19)166 (2)
C8—H8···O6i0.952.503.436 (2)169
C11—H11···O2ii0.952.523.377 (2)150
C12—H12···O4iii0.952.463.118 (2)126
Symmetry codes: (i) −x+1, −y, −z+1; (ii) x−1, y+1, z; (iii) −x+1, −y+1, −z.
 

Acknowledgements

We gratefully thank the Ministry of Higher Education (Malaysia) and the University of Malaya (UM) for funding structural studies through the High-Impact Research scheme (UM·C/HIR-MOHE/SC/03).

References

First citationArman, H. D., Miller, T. & Tiekink, E. R. T. (2013). Z. Kristallogr. Cryst. Mat. 228, 295–303.  Web of Science CSD CrossRef CAS Google Scholar
 First citationBrandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.  Google Scholar
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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 69| Part 11| November 2013| Page o1606
doi:10.1107/S1600536813026810
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