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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 68| Part 12| December 2012| Page o3361
doi:10.1107/S1600536812046077

4-Amino­pyridinium 2-chloro-4-nitro­benzoate monohydrate

Kelsey L. Saviga and Andreas Lemmerera*

aMolecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Johannesburg, PO Wits 2050, South Africa
*Correspondence e-mail: andreas.lemmerer@wits.ac.za

(Received 11 October 2012; accepted 7 November 2012; online 17 November 2012)

In the title hydrated mol­ecular salt, C5H7N2+·C7H3ClNO4−·H2O, the ions and water mol­ecules assemble into ribbons of R65(22) rings along the c axis via O(water)—H⋯O−, N+—H⋯O(water) and N—H⋯O− hydrogen bonds. N—H⋯O− hydrogen bonds connect adjacent ribbons along the c-axis direction via R44(12) rings, forming hydrogen-bonded layers. The CO2 and NO2 groups make dihedral angles of 81.8 (2) and 1.4 (2)°, respectively, with the ring in the anion.

Related literature

For related structures, see: Lemmerer et al. (2010[Lemmerer, A., Esterhuysen, C. & Bernstein, J. (2010). J. Pharm. Sci. 99, 4054-4071.]). For graph-set notation, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 35, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data

  • C5H7N2+·C7H3ClNO4−·H2O

  • Mr = 313.7

  • Monoclinic, P 21 /c

  • a = 14.4500 (5) Å

  • b = 14.3300 (5) Å

  • c = 6.9918 (2) Å

  • β = 97.804 (2)°

  • V = 1434.37 (8) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.29 mm−1

  • T = 173 K

  • 0.78 × 0.31 × 0.09 mm
Data collection

  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: integration (XPREP; Bruker, 2004[Bruker (2004). SAINT-Plus and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.896, Tmax = 0.977

  • 14928 measured reflections

  • 3456 independent reflections

  • 2685 reflections with I > 2σ(I)

  • Rint = 0.061
Refinement

  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.122

  • S = 1.04

  • 3456 reflections

  • 210 parameters

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

  • Δρmax = 0.5 e Å−3

  • Δρmin = −0.36 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N2—H2⋯O1Wi 0.93 (3) 1.72 (3) 2.641 (2) 170 (2)
N3—H3A⋯O1 0.94 (2) 1.99 (2) 2.926 (2) 171.1 (19)
N3—H3B⋯O2ii 0.84 (2) 2.16 (3) 2.982 (2) 165 (2)
O1W—H1W⋯O1iii 0.75 (3) 1.96 (3) 2.698 (2) 166 (3)
O1W—H2W⋯O2 0.78 (4) 1.99 (4) 2.729 (2) 158 (3)
Symmetry codes: (i) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (ii) -x+2, -y+1, -z+1; (iii) x, y, z+1.

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-Plus (Bruker, 2004[Bruker (2004). SAINT-Plus and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-Plus and XPREP (Bruker 2004[Bruker (2004). SAINT-Plus and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and DIAMOND (Brandenburg, 1999[Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812046077/fy2073sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812046077/fy2073Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812046077/fy2073Isup3.mol

Supporting information file. DOI: 10.1107/S1600536812046077/fy2073Isup4.cml

checkCIF report


Comment top

The title molecular salt is part of a larger research project looking at the factors that determine if a salt or a co-crystal forms between a specific carboxylic acid and various pyridine ring systems (Lemmerer et al., 2010).

In molecular salt (I) (Fig. 1), formed by dissolving 4-aminopyridine and 2-chloro-4-nitrobenzoic acid in methanol, two kinds of hydrogen-bonded rings are formed. The ring R56(22) (Bernstein et al., 1995) uses O1W—H···O-, N+—H···O and N—H···O- hydrogen bonds to connect all three species together into a 1-D ribbon (Fig. 2) along the c-axis. In addition, a R44(12) ring is formed between two amine groups and two carboxylate groups to connect two ribbons together to form layers (Fig. 3).

Related literature top

For related structures, see: Lemmerer et al. (2010). For graph-set notation, see: Bernstein et al. (1995).

Experimental top

Crystals were grown by slow evaporation of a methanol solution of 2-chloro-4-nitrobenzoic acid (0.100 g; 0.496 mmol) and 4-aminopyridine (0.047 g; 0.50 mmol) in 8 ml of methanol, and afforded colourless plates after three days of slow evaporation at ambient conditions.

Refinement top

The aromatic C-bound H atoms were geometrically placed with C—H bond lengths of 0.95 Å, and were refined as riding with Uiso(H) = 1.2Ueq(C). The O-bound H atoms of the water molecule and the N-bound H atoms were located in the difference map and their coordinates as well as isotropic displacement parameters were refined freely. The residual electron density around the O atom of the water molecule was found to not correspond to any H atoms by inspection of the hydrogen bonding geometry.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus and XPREP (Bruker 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 1999); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of (I) showing the atomic numbering scheme. Displacement ellipsoids are shown at the 50% probability level.
[Figure 2] Fig. 2. Hydrogen bonding diagram of (I) showing the R56(22) rings to form ribbons. Intermolecular hydrogen bonds are shown as dashed red lines forming dimers. Atoms with superscrips (i) and (ii) are at the symmetry positions (x, y, z - 1) and (x, -y + 1/2, z - 1/2) respectively.
[Figure 3] Fig. 3. The layers form by combining the one-dimensional ribbons using R44(12) rings.
4-Aminopyridinium 2-chloro-4-nitrobenzoate monohydrate top
Crystal data top
C5H7N2+·C7H3ClNO4−·H2OF(000) = 648
Mr = 313.7Dx = 1.453 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 4262 reflections
a = 14.4500 (5) Åθ = 2.8–27.8°
b = 14.3300 (5) ŵ = 0.29 mm−1
c = 6.9918 (2) ÅT = 173 K
β = 97.804 (2)°Plate, colourless
V = 1434.37 (8) Å30.78 × 0.31 × 0.09 mm
Z = 4
Data collection top
Bruker APEXII CCD area-detector
diffractometer		2685 reflections with I > 2σ(I)
ω scansRint = 0.061
Absorption correction: integration
(XPREP; Bruker, 2004)		θmax = 28°, θmin = 1.4°
Tmin = 0.896, Tmax = 0.977h = −19→19
14928 measured reflectionsk = −18→18
3456 independent reflectionsl = −8→9
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.043 w = 1/[σ2(Fo2) + (0.0662P)2 + 0.1397P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.122(Δ/σ)max < 0.001
S = 1.04Δρmax = 0.5 e Å−3
3456 reflectionsΔρmin = −0.36 e Å−3
210 parameters
Crystal data top
C5H7N2+·C7H3ClNO4−·H2OV = 1434.37 (8) Å3
Mr = 313.7Z = 4
Monoclinic, P21/cMo Kα radiation
a = 14.4500 (5) ŵ = 0.29 mm−1
b = 14.3300 (5) ÅT = 173 K
c = 6.9918 (2) Å0.78 × 0.31 × 0.09 mm
β = 97.804 (2)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer		3456 independent reflections
Absorption correction: integration
(XPREP; Bruker, 2004)		2685 reflections with I > 2σ(I)
Tmin = 0.896, Tmax = 0.977Rint = 0.061
14928 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.122H atoms treated by a mixture of independent and constrained refinement
S = 1.04Δρmax = 0.5 e Å−3
3456 reflectionsΔρmin = −0.36 e Å−3
210 parameters
Special details top

Experimental. Numerical integration absorption corrections based on indexed crystal faces were applied using the XPREP routine (Bruker, 2004)

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.69246 (11)0.61389 (11)0.2594 (2)0.0261 (3)
C20.61757 (12)0.55610 (11)0.2858 (2)0.0271 (3)
C30.52758 (11)0.57500 (11)0.2008 (2)0.0284 (3)
H30.47720.53480.21880.034*
C40.51347 (11)0.65438 (12)0.0887 (2)0.0290 (4)
C50.58469 (12)0.71419 (12)0.0592 (2)0.0325 (4)
H50.57250.7687−0.01760.039*
C60.67437 (12)0.69317 (12)0.1438 (2)0.0311 (4)
H60.72450.73320.12320.037*
C70.79130 (11)0.59307 (11)0.3515 (2)0.0291 (3)
N10.41775 (10)0.67644 (11)0.0004 (2)0.0349 (3)
O10.84325 (9)0.55490 (9)0.24589 (19)0.0412 (3)
O20.81313 (9)0.61801 (10)0.52270 (17)0.0424 (3)
O30.35519 (9)0.62315 (10)0.0282 (2)0.0462 (3)
O40.40575 (10)0.74821 (11)−0.0962 (2)0.0513 (4)
Cl10.63660 (3)0.45679 (3)0.42817 (7)0.04119 (15)
C80.96351 (14)0.15836 (13)0.3659 (2)0.0361 (4)
H81.00190.10490.39360.043*
C91.00312 (12)0.24412 (13)0.3780 (2)0.0341 (4)
H91.06870.25060.41230.041*
C100.94613 (12)0.32426 (12)0.3393 (2)0.0293 (4)
C110.84995 (12)0.30971 (12)0.2835 (2)0.0309 (4)
H110.80950.36140.25270.037*
C120.81509 (13)0.22161 (13)0.2739 (2)0.0352 (4)
H120.750.21240.2370.042*
N20.87086 (12)0.14714 (11)0.3155 (2)0.0357 (3)
N30.98294 (12)0.40973 (11)0.3540 (2)0.0368 (4)
H20.8439 (17)0.0887 (18)0.322 (3)0.061 (7)*
H3A0.9432 (16)0.4610 (15)0.322 (3)0.045 (6)*
H3B1.0408 (17)0.4127 (15)0.391 (3)0.048 (6)*
O1W0.8108 (2)0.52435 (14)0.8618 (3)0.1094 (11)
H1W0.817 (2)0.541 (2)0.965 (5)0.080 (10)*
H2W0.806 (2)0.562 (2)0.781 (5)0.096 (11)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0257 (8)0.0296 (8)0.0228 (7)0.0026 (6)0.0032 (6)−0.0001 (6)
C20.0310 (8)0.0261 (8)0.0245 (7)0.0017 (6)0.0048 (6)0.0017 (6)
C30.0268 (8)0.0306 (8)0.0281 (8)−0.0034 (6)0.0046 (6)−0.0036 (6)
C40.0241 (8)0.0377 (9)0.0244 (7)0.0046 (6)0.0007 (6)−0.0018 (6)
C50.0319 (9)0.0339 (9)0.0312 (8)0.0036 (7)0.0030 (7)0.0082 (7)
C60.0265 (9)0.0340 (9)0.0325 (8)−0.0007 (7)0.0033 (6)0.0062 (7)
C70.0260 (8)0.0281 (8)0.0319 (8)0.0004 (6)−0.0007 (6)0.0059 (6)
N10.0256 (8)0.0466 (9)0.0316 (7)0.0043 (6)−0.0001 (6)−0.0049 (7)
O10.0307 (7)0.0477 (8)0.0437 (7)0.0115 (6)−0.0002 (5)−0.0040 (6)
O20.0367 (7)0.0580 (8)0.0302 (6)−0.0009 (6)−0.0039 (5)−0.0001 (6)
O30.0254 (7)0.0589 (9)0.0530 (8)−0.0023 (6)0.0004 (6)−0.0042 (7)
O40.0382 (8)0.0584 (9)0.0541 (8)0.0136 (7)−0.0054 (6)0.0154 (7)
Cl10.0433 (3)0.0341 (2)0.0463 (3)0.00160 (18)0.0065 (2)0.01473 (18)
C80.0429 (11)0.0369 (9)0.0287 (8)0.0107 (8)0.0059 (7)0.0010 (7)
C90.0295 (9)0.0400 (10)0.0323 (8)0.0069 (7)0.0027 (7)0.0002 (7)
C100.0306 (9)0.0360 (9)0.0214 (7)0.0035 (7)0.0037 (6)−0.0002 (6)
C110.0282 (9)0.0381 (9)0.0262 (8)0.0056 (7)0.0033 (6)0.0018 (7)
C120.0316 (9)0.0472 (10)0.0266 (8)−0.0011 (7)0.0030 (7)0.0004 (7)
N20.0440 (9)0.0359 (8)0.0275 (7)−0.0008 (7)0.0060 (6)0.0002 (6)
N30.0289 (8)0.0361 (8)0.0435 (9)0.0021 (7)−0.0018 (7)−0.0013 (7)
O1W0.249 (4)0.0447 (10)0.0407 (10)0.0464 (14)0.0425 (14)0.0092 (9)
Geometric parameters (Å, º) top
C1—C21.395 (2)C8—N21.347 (2)
C1—C61.398 (2)C8—C91.353 (3)
C1—C71.515 (2)C8—H80.95
C2—C31.381 (2)C9—C101.418 (2)
C2—Cl11.7369 (16)C9—H90.95
C3—C41.381 (2)C10—N31.334 (2)
C3—H30.95C10—C111.407 (2)
C4—C51.376 (2)C11—C121.358 (2)
C4—N11.471 (2)C11—H110.95
C5—C61.383 (2)C12—N21.345 (2)
C5—H50.95C12—H120.95
C6—H60.95N2—H20.93 (3)
C7—O21.248 (2)N3—H3A0.94 (2)
C7—O11.248 (2)N3—H3B0.84 (2)
N1—O31.219 (2)O1W—H1W0.75 (3)
N1—O41.230 (2)O1W—H2W0.78 (4)
C2—C1—C6118.13 (15)O4—N1—C4117.71 (15)
C2—C1—C7122.05 (14)N2—C8—C9121.43 (16)
C6—C1—C7119.83 (14)N2—C8—H8119.3
C3—C2—C1121.91 (15)C9—C8—H8119.3
C3—C2—Cl1118.28 (12)C8—C9—C10119.60 (17)
C1—C2—Cl1119.80 (12)C8—C9—H9120.2
C4—C3—C2117.63 (15)C10—C9—H9120.2
C4—C3—H3121.2N3—C10—C11121.74 (16)
C2—C3—H3121.2N3—C10—C9120.92 (16)
C5—C4—C3122.84 (15)C11—C10—C9117.33 (16)
C5—C4—N1118.88 (15)C12—C11—C10119.83 (16)
C3—C4—N1118.27 (15)C12—C11—H11120.1
C4—C5—C6118.46 (15)C10—C11—H11120.1
C4—C5—H5120.8N2—C12—C11121.31 (17)
C6—C5—H5120.8N2—C12—H12119.3
C5—C6—C1121.02 (16)C11—C12—H12119.3
C5—C6—H6119.5C12—N2—C8120.46 (16)
C1—C6—H6119.5C12—N2—H2118.9 (15)
O2—C7—O1126.79 (16)C8—N2—H2120.3 (15)
O2—C7—C1116.89 (15)C10—N3—H3A118.3 (13)
O1—C7—C1116.28 (14)C10—N3—H3B116.1 (15)
O3—N1—O4124.01 (15)H3A—N3—H3B126 (2)
O3—N1—C4118.28 (15)H1W—O1W—H2W117 (3)
C6—C1—C2—C30.4 (2)C2—C1—C7—O199.31 (18)
C7—C1—C2—C3−179.64 (14)C6—C1—C7—O1−80.7 (2)
C6—C1—C2—Cl1179.99 (12)C5—C4—N1—O3−179.69 (15)
C7—C1—C2—Cl10.0 (2)C3—C4—N1—O3−0.8 (2)
C1—C2—C3—C4−0.6 (2)C5—C4—N1—O4−0.2 (2)
Cl1—C2—C3—C4179.75 (12)C3—C4—N1—O4178.68 (15)
C2—C3—C4—C50.1 (2)N2—C8—C9—C100.8 (3)
C2—C3—C4—N1−178.79 (14)C8—C9—C10—N3178.61 (16)
C3—C4—C5—C60.8 (3)C8—C9—C10—C11−1.9 (2)
N1—C4—C5—C6179.59 (14)N3—C10—C11—C12−178.78 (16)
C4—C5—C6—C1−1.0 (3)C9—C10—C11—C121.8 (2)
C2—C1—C6—C50.5 (2)C10—C11—C12—N2−0.5 (2)
C7—C1—C6—C5−179.52 (15)C11—C12—N2—C8−0.8 (2)
C2—C1—C7—O2−82.6 (2)C9—C8—N2—C120.6 (2)
C6—C1—C7—O297.40 (18)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···O1Wi0.93 (3)1.72 (3)2.641 (2)170 (2)
N3—H3A···O10.94 (2)1.99 (2)2.926 (2)171.1 (19)
N3—H3B···O2ii0.84 (2)2.16 (3)2.982 (2)165 (2)
O1W—H1W···O1iii0.75 (3)1.96 (3)2.698 (2)166 (3)
O1W—H2W···O20.78 (4)1.99 (4)2.729 (2)158 (3)
Symmetry codes: (i) x, −y+1/2, z−1/2; (ii) −x+2, −y+1, −z+1; (iii) x, y, z+1.

Experimental details

Crystal data
Chemical formulaC5H7N2+·C7H3ClNO4−·H2O
Mr313.7
Crystal system, space groupMonoclinic, P21/c
Temperature (K)173
a, b, c (Å)14.4500 (5), 14.3300 (5), 6.9918 (2)
β (°) 97.804 (2)
V (Å3)1434.37 (8)
Z4
Radiation typeMo Kα
µ (mm−1)0.29
Crystal size (mm)0.78 × 0.31 × 0.09
Data collection
DiffractometerBruker APEXII CCD area-detector
diffractometer
Absorption correctionIntegration
(XPREP; Bruker, 2004)
Tmin, Tmax0.896, 0.977
No. of measured, independent and
observed [I > 2σ(I)] reflections		14928, 3456, 2685
Rint0.061
(sin θ/λ)max (Å−1)0.661
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.122, 1.04
No. of reflections3456
No. of parameters210
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.5, −0.36

Computer programs: APEX2 (Bruker, 2005), SAINT-Plus (Bruker, 2004), SAINT-Plus and XPREP (Bruker 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 1999), WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···O1Wi0.93 (3)1.72 (3)2.641 (2)170 (2)
N3—H3A···O10.94 (2)1.99 (2)2.926 (2)171.1 (19)
N3—H3B···O2ii0.84 (2)2.16 (3)2.982 (2)165 (2)
O1W—H1W···O1iii0.75 (3)1.96 (3)2.698 (2)166 (3)
O1W—H2W···O20.78 (4)1.99 (4)2.729 (2)158 (3)
Symmetry codes: (i) x, −y+1/2, z−1/2; (ii) −x+2, −y+1, −z+1; (iii) x, y, z+1.
 

Acknowledgements

This work was supported by the University of the Witwatersrand and the Mol­ecular Sciences Institute, which are thanked for providing the infrastructure required to do this work, and the Friedel Sellshop grant for financial support.

References

First citationBernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 35, 1555–1573.  CrossRef Web of Science Google Scholar
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ISSN: 2056-9890
Volume 68| Part 12| December 2012| Page o3361
doi:10.1107/S1600536812046077
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