4-Amino-pyridinium 4-nitro-benzoate 4-nitro-benzoic acid.

The asymmetric unit of the title compound, C(5)H(7)N(2) (+)·C(7)H(4)NO(4) (-)·C(7)H(5)NO(4), consists of an amino-pyridinium cation, a 4-nitro-benzoate anion and a neutral 4-nitro-benzoic acid mol-ecule. The pyridine ring forms dihedral angles of 64.70 (5)° and 70.37 (5)°, respectively, with the benzene rings of 4-nitro-benzoic acid and 4-nitro-benzoate. In the crystal structure, the cations, anions and the neutral 4-nitro-benzoic acid mol-ecules are linked by O-H⋯O and N-H⋯O hydrogen bonds, forming a two-dimensional network parallel to (001). Adjacent networks are cross-linked via C-H⋯O hydrogen bonds and π-π stacking inter-actions [centroid-centroid distances 3.6339 (6) and 3.6566 (6) Å].

Related literature

For the biological activity of 4-amino­pyridine, see: Judge et al. (2006 ▶); Schwid et al. (1997 ▶); Strupp et al. (2004 ▶). For related structures, see: Chao & Schempp (1977 ▶); Anderson et al. (2005 ▶); Andrau & White, (2003 ▶); Bhattacharya et al. (1994 ▶); Karle et al. (2003 ▶).

Experimental

Crystal data

C5H7N2 +·C7H4NO4 −·C7H5NO4

M = 428.36

Triclinic,

a = 6.4561 (1) Å

b = 6.8598 (1) Å

c = 20.9055 (3) Å

α = 85.826 (1)°

β = 87.975 (1)°

γ = 86.188 (1)°

V = 920.92 (2) Å3

Z = 2

Mo Kα radiation

μ = 0.12 mm−1

T = 100.0 (1) K

0.40 × 0.36 × 0.29 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T min = 0.952, T max = 0.965

24945 measured reflections

6647 independent reflections

5169 reflections with I > 2σ(I)

R int = 0.031

Refinement

R[F 2 > 2σ(F 2)] = 0.044

wR(F 2) = 0.132

S = 1.05

6647 reflections

284 parameters

1 restraint

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.43 e Å−3

Δρmin = −0.39 e Å−3

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: APEX2; data reduction: SAINT (Bruker, 2005 ▶); program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808027761/ci2664sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808027761/ci2664Isup2.hkl

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

C5H7N2+·C7H4NO4−·C7H5NO4	Z = 2
Mr = 428.36	F(000) = 444
Triclinic, P1	Dx = 1.545 Mg m−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.4561 (1) Å	Cell parameters from 6200 reflections
b = 6.8598 (1) Å	θ = 2.2–29.2°
c = 20.9055 (3) Å	µ = 0.12 mm−1
α = 85.826 (1)°	T = 100 K
β = 87.975 (1)°	Block, colourless
γ = 86.188 (1)°	0.40 × 0.36 × 0.29 mm
V = 920.92 (2) Å3

Bruker SMART APEXII CCD area-detector diffractometer	6647 independent reflections
Radiation source: fine-focus sealed tube	5169 reflections with I > 2σ(I)
graphite	Rint = 0.031
φ and ω scans	θmax = 32.5°, θmin = 1.0°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −9→9
Tmin = 0.952, Tmax = 0.965	k = −10→10
24945 measured reflections	l = −31→31

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)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.132	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ2(Fo2) + (0.0736P)2 + 0.1221P] where P = (Fo2 + 2Fc2)/3
6647 reflections	(Δ/σ)max = 0.001
284 parameters	Δρmax = 0.43 e Å−3
1 restraint	Δρmin = −0.39 e Å−3

Experimental. The data was collected with the Oxford Cyrosystem Cobra low-temperature attachment.

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.

	x	y	z	Uiso*/Ueq
O1A	0.61416 (13)	0.64153 (13)	0.61139 (4)	0.02534 (18)
O1B	1.43798 (12)	0.64460 (14)	1.07244 (4)	0.02613 (19)
O2A	0.89023 (12)	0.63198 (13)	0.54960 (4)	0.02492 (18)
O2B	1.15700 (13)	0.66730 (15)	1.13139 (4)	0.02794 (19)
O3A	0.31404 (11)	0.97209 (12)	0.29069 (4)	0.02024 (16)
H1O3	0.2342	1.0163	0.2628	0.030*
O3B	0.89111 (11)	0.90736 (11)	0.80183 (4)	0.01831 (15)
O4A	0.02402 (11)	0.98398 (11)	0.35318 (4)	0.01950 (16)
O4B	0.59084 (12)	0.90329 (13)	0.85892 (4)	0.02425 (18)
N1A	0.70215 (13)	0.66162 (13)	0.55851 (4)	0.01667 (17)
N1B	1.24848 (13)	0.67136 (13)	1.07904 (4)	0.01646 (17)
N2	0.80980 (14)	0.30341 (13)	0.29153 (4)	0.01904 (18)
N3	0.73597 (13)	0.85350 (13)	0.20200 (5)	0.02020 (18)
H3A	0.8354	0.9309	0.2022	0.024*
H3B	0.6223	0.8922	0.1834	0.024*
C1A	0.24956 (15)	0.84572 (14)	0.46101 (5)	0.01507 (18)
H1AA	0.1084	0.8790	0.4667	0.018*
C1B	1.11431 (15)	0.75402 (14)	0.90711 (5)	0.01505 (18)
H1BA	1.1788	0.7482	0.8667	0.018*
C2A	0.36551 (15)	0.77640 (14)	0.51351 (5)	0.01593 (18)
H2AA	0.3048	0.7633	0.5545	0.019*
C2B	1.22778 (15)	0.70459 (14)	0.96180 (5)	0.01522 (18)
H2BA	1.3685	0.6664	0.9587	0.018*
C3B	1.12614 (14)	0.71350 (14)	1.02109 (5)	0.01397 (17)
C3A	0.57532 (15)	0.72731 (14)	0.50276 (5)	0.01424 (17)
C4A	0.67164 (15)	0.74110 (15)	0.44250 (5)	0.01592 (18)
H4AA	0.8119	0.7038	0.4369	0.019*
C4B	0.91589 (15)	0.76542 (14)	1.02843 (5)	0.01527 (18)
H4BA	0.8513	0.7667	1.0689	0.018*
C5A	0.55303 (15)	0.81214 (15)	0.39071 (5)	0.01621 (18)
H5AA	0.6142	0.8239	0.3498	0.019*
C5B	0.80500 (15)	0.81538 (14)	0.97324 (5)	0.01517 (18)
H5BA	0.6638	0.8512	0.9766	0.018*
C6A	0.34218 (14)	0.86598 (14)	0.39989 (5)	0.01412 (17)
C6B	0.90370 (14)	0.81237 (14)	0.91270 (5)	0.01388 (17)
C7A	0.21250 (15)	0.94696 (14)	0.34447 (5)	0.01498 (18)
C7B	0.78049 (15)	0.87820 (14)	0.85437 (5)	0.01578 (18)
C8	0.62995 (16)	0.35854 (16)	0.26207 (5)	0.0195 (2)
H8A	0.5260	0.2709	0.2623	0.023*
C9	0.59889 (15)	0.54066 (15)	0.23204 (5)	0.01760 (19)
H9A	0.4736	0.5775	0.2126	0.021*
C10	0.75805 (15)	0.67391 (15)	0.23052 (5)	0.01566 (18)
C11	0.94501 (15)	0.60896 (15)	0.26128 (5)	0.01670 (19)
H11A	1.0538	0.6914	0.2611	0.020*
C12	0.96496 (16)	0.42621 (16)	0.29097 (5)	0.0186 (2)
H12A	1.0877	0.3849	0.3113	0.022*
H1N2	0.839 (2)	0.1892 (15)	0.3080 (7)	0.029 (4)*

	U11	U22	U33	U12	U13	U23
O1A	0.0250 (4)	0.0384 (5)	0.0118 (4)	−0.0024 (3)	−0.0008 (3)	0.0048 (3)
O1B	0.0158 (3)	0.0428 (5)	0.0191 (4)	0.0041 (3)	−0.0028 (3)	−0.0013 (3)
O2A	0.0172 (3)	0.0361 (5)	0.0207 (4)	0.0016 (3)	−0.0036 (3)	0.0012 (3)
O2B	0.0228 (4)	0.0485 (5)	0.0115 (4)	0.0012 (3)	0.0006 (3)	0.0003 (3)
O3A	0.0183 (3)	0.0303 (4)	0.0116 (3)	−0.0013 (3)	−0.0025 (3)	0.0027 (3)
O3B	0.0174 (3)	0.0258 (4)	0.0114 (3)	−0.0009 (3)	−0.0003 (3)	0.0006 (3)
O4A	0.0158 (3)	0.0236 (4)	0.0182 (4)	0.0011 (3)	−0.0016 (3)	0.0026 (3)
O4B	0.0145 (3)	0.0368 (5)	0.0198 (4)	0.0011 (3)	−0.0020 (3)	0.0071 (3)
N1A	0.0179 (4)	0.0178 (4)	0.0145 (4)	−0.0016 (3)	−0.0034 (3)	−0.0001 (3)
N1B	0.0167 (4)	0.0194 (4)	0.0131 (4)	0.0003 (3)	−0.0014 (3)	−0.0010 (3)
N2	0.0213 (4)	0.0188 (4)	0.0161 (4)	0.0014 (3)	0.0009 (3)	0.0017 (3)
N3	0.0160 (4)	0.0212 (4)	0.0224 (5)	0.0005 (3)	−0.0014 (3)	0.0045 (3)
C1A	0.0146 (4)	0.0166 (4)	0.0140 (4)	−0.0011 (3)	−0.0003 (3)	−0.0006 (3)
C1B	0.0156 (4)	0.0177 (4)	0.0114 (4)	0.0009 (3)	0.0001 (3)	−0.0004 (3)
C2A	0.0172 (4)	0.0180 (4)	0.0127 (4)	−0.0030 (3)	0.0005 (3)	−0.0001 (3)
C2B	0.0139 (4)	0.0175 (4)	0.0140 (4)	0.0009 (3)	−0.0001 (3)	−0.0010 (3)
C3B	0.0151 (4)	0.0154 (4)	0.0114 (4)	−0.0001 (3)	−0.0023 (3)	−0.0003 (3)
C3A	0.0168 (4)	0.0143 (4)	0.0118 (4)	−0.0017 (3)	−0.0030 (3)	0.0002 (3)
C4A	0.0141 (4)	0.0193 (4)	0.0143 (4)	−0.0007 (3)	−0.0005 (3)	−0.0013 (3)
C4B	0.0158 (4)	0.0175 (4)	0.0125 (4)	−0.0018 (3)	0.0009 (3)	−0.0007 (3)
C5A	0.0163 (4)	0.0206 (4)	0.0117 (4)	−0.0015 (3)	0.0000 (3)	−0.0013 (3)
C5B	0.0131 (4)	0.0180 (4)	0.0142 (4)	−0.0005 (3)	−0.0002 (3)	0.0001 (3)
C6A	0.0154 (4)	0.0147 (4)	0.0125 (4)	−0.0018 (3)	−0.0021 (3)	−0.0006 (3)
C6B	0.0143 (4)	0.0151 (4)	0.0122 (4)	−0.0013 (3)	−0.0014 (3)	0.0005 (3)
C7A	0.0173 (4)	0.0153 (4)	0.0125 (4)	−0.0026 (3)	−0.0018 (3)	0.0002 (3)
C7B	0.0157 (4)	0.0167 (4)	0.0149 (4)	−0.0007 (3)	−0.0022 (3)	−0.0001 (3)
C8	0.0175 (4)	0.0233 (5)	0.0178 (5)	−0.0023 (4)	0.0008 (4)	−0.0016 (4)
C9	0.0138 (4)	0.0231 (5)	0.0156 (5)	−0.0006 (3)	−0.0012 (3)	−0.0001 (4)
C10	0.0144 (4)	0.0199 (4)	0.0123 (4)	0.0012 (3)	0.0005 (3)	−0.0009 (3)
C11	0.0151 (4)	0.0203 (4)	0.0148 (4)	−0.0004 (3)	−0.0020 (3)	−0.0015 (4)
C12	0.0178 (4)	0.0232 (5)	0.0143 (5)	0.0029 (3)	−0.0023 (3)	−0.0010 (4)

O1A—N1A	1.2278 (12)	C2A—H2AA	0.93
O1B—N1B	1.2294 (11)	C2B—C3B	1.3851 (14)
O2A—N1A	1.2276 (11)	C2B—H2BA	0.93
O2B—N1B	1.2244 (12)	C3B—C4B	1.3863 (13)
O3A—C7A	1.2877 (12)	C3A—C4A	1.3848 (14)
O3A—H1O3	0.8200	C4A—C5A	1.3888 (14)
O3B—C7B	1.2993 (12)	C4A—H4AA	0.93
O4A—C7A	1.2362 (12)	C4B—C5B	1.3890 (14)
O4B—C7B	1.2263 (12)	C4B—H4BA	0.93
N1A—C3A	1.4743 (12)	C5A—C6A	1.3969 (13)
N1B—C3B	1.4702 (13)	C5A—H5AA	0.93
N2—C12	1.3502 (14)	C5B—C6B	1.3977 (14)
N2—C8	1.3523 (14)	C5B—H5BA	0.93
N2—H1N2	0.844 (9)	C6A—C7A	1.5049 (13)
N3—C10	1.3301 (13)	C6B—C7B	1.5047 (13)
N3—H3A	0.86	C8—C9	1.3626 (15)
N3—H3B	0.86	C8—H8A	0.93
C1A—C2A	1.3877 (14)	C9—C10	1.4180 (14)
C1A—C6A	1.3930 (14)	C9—H9A	0.93
C1A—H1AA	0.93	C10—C11	1.4180 (13)
C1B—C2B	1.3888 (13)	C11—C12	1.3580 (15)
C1B—C6B	1.3949 (13)	C11—H11A	0.93
C1B—H1BA	0.93	C12—H12A	0.93
C2A—C3A	1.3884 (13)
C7A—O3A—H1O3	109.5	C3B—C4B—H4BA	121.2
O2A—N1A—O1A	123.62 (9)	C5B—C4B—H4BA	121.2
O2A—N1A—C3A	118.18 (9)	C4A—C5A—C6A	120.21 (9)
O1A—N1A—C3A	118.20 (8)	C4A—C5A—H5AA	119.9
O2B—N1B—O1B	123.36 (9)	C6A—C5A—H5AA	119.9
O2B—N1B—C3B	118.43 (8)	C4B—C5B—C6B	120.61 (9)
O1B—N1B—C3B	118.20 (9)	C4B—C5B—H5BA	119.7
C12—N2—C8	120.86 (9)	C6B—C5B—H5BA	119.7
C12—N2—H1N2	115.2 (11)	C1A—C6A—C5A	119.99 (9)
C8—N2—H1N2	123.7 (11)	C1A—C6A—C7A	119.15 (8)
C10—N3—H3A	120.0	C5A—C6A—C7A	120.86 (9)
C10—N3—H3B	120.0	C1B—C6B—C5B	120.08 (9)
H3A—N3—H3B	120.0	C1B—C6B—C7B	121.02 (9)
C2A—C1A—C6A	120.74 (9)	C5B—C6B—C7B	118.88 (8)
C2A—C1A—H1AA	119.6	O4A—C7A—O3A	125.63 (9)
C6A—C1A—H1AA	119.6	O4A—C7A—C6A	119.65 (9)
C2B—C1B—C6B	120.04 (9)	O3A—C7A—C6A	114.72 (8)
C2B—C1B—H1BA	120.0	O4B—C7B—O3B	125.05 (9)
C6B—C1B—H1BA	120.0	O4B—C7B—C6B	120.18 (9)
C1A—C2A—C3A	117.70 (9)	O3B—C7B—C6B	114.75 (8)
C1A—C2A—H2AA	121.2	N2—C8—C9	120.94 (10)
C3A—C2A—H2AA	121.2	N2—C8—H8A	119.5
C3B—C2B—C1B	118.35 (9)	C9—C8—H8A	119.5
C3B—C2B—H2BA	120.8	C8—C9—C10	119.85 (9)
C1B—C2B—H2BA	120.8	C8—C9—H9A	120.1
C2B—C3B—C4B	123.20 (9)	C10—C9—H9A	120.1
C2B—C3B—N1B	118.36 (8)	N3—C10—C11	120.35 (9)
C4B—C3B—N1B	118.42 (9)	N3—C10—C9	122.38 (9)
C4A—C3A—C2A	123.18 (9)	C11—C10—C9	117.27 (9)
C4A—C3A—N1A	118.57 (8)	C12—C11—C10	119.88 (9)
C2A—C3A—N1A	118.23 (9)	C12—C11—H11A	120.1
C3A—C4A—C5A	118.16 (9)	C10—C11—H11A	120.1
C3A—C4A—H4AA	120.9	N2—C12—C11	121.19 (9)
C5A—C4A—H4AA	120.9	N2—C12—H12A	119.4
C3B—C4B—C5B	117.67 (9)	C11—C12—H12A	119.4
C6A—C1A—C2A—C3A	−0.39 (14)	C4A—C5A—C6A—C1A	−0.97 (14)
C6B—C1B—C2B—C3B	0.50 (14)	C4A—C5A—C6A—C7A	178.78 (9)
C1B—C2B—C3B—C4B	1.38 (15)	C2B—C1B—C6B—C5B	−1.98 (14)
C1B—C2B—C3B—N1B	−176.79 (9)	C2B—C1B—C6B—C7B	176.30 (9)
O2B—N1B—C3B—C2B	−175.56 (9)	C4B—C5B—C6B—C1B	1.65 (14)
O1B—N1B—C3B—C2B	5.40 (14)	C4B—C5B—C6B—C7B	−176.66 (9)
O2B—N1B—C3B—C4B	6.18 (14)	C1A—C6A—C7A—O4A	−4.01 (14)
O1B—N1B—C3B—C4B	−172.86 (9)	C5A—C6A—C7A—O4A	176.24 (9)
C1A—C2A—C3A—C4A	−1.18 (15)	C1A—C6A—C7A—O3A	175.76 (8)
C1A—C2A—C3A—N1A	177.40 (8)	C5A—C6A—C7A—O3A	−3.99 (13)
O2A—N1A—C3A—C4A	3.87 (13)	C1B—C6B—C7B—O4B	170.01 (9)
O1A—N1A—C3A—C4A	−176.87 (9)	C5B—C6B—C7B—O4B	−11.69 (14)
O2A—N1A—C3A—C2A	−174.77 (9)	C1B—C6B—C7B—O3B	−11.13 (13)
O1A—N1A—C3A—C2A	4.48 (13)	C5B—C6B—C7B—O3B	167.17 (9)
C2A—C3A—C4A—C5A	1.64 (15)	C12—N2—C8—C9	−1.21 (16)
N1A—C3A—C4A—C5A	−176.93 (8)	N2—C8—C9—C10	1.08 (16)
C2B—C3B—C4B—C5B	−1.70 (15)	C8—C9—C10—N3	−179.88 (10)
N1B—C3B—C4B—C5B	176.47 (9)	C8—C9—C10—C11	−0.23 (15)
C3A—C4A—C5A—C6A	−0.53 (14)	N3—C10—C11—C12	179.16 (10)
C3B—C4B—C5B—C6B	0.15 (14)	C9—C10—C11—C12	−0.50 (15)
C2A—C1A—C6A—C5A	1.44 (14)	C8—N2—C12—C11	0.45 (16)
C2A—C1A—C6A—C7A	−178.30 (9)	C10—C11—C12—N2	0.41 (16)

D—H···A	D—H	H···A	D···A	D—H···A
O3A—H1O3···O3Bi	0.82	1.63	2.4457 (11)	170
N3—H3A···O3Bii	0.86	2.14	2.9977 (12)	172
N3—H3B···O4Bi	0.86	2.07	2.8758 (12)	155
N2—H1N2···O4Aiii	0.85 (1)	1.99 (1)	2.7726 (12)	153 (1)
C2B—H2BA···O1Biv	0.93	2.52	3.2187 (13)	133
C8—H8A···O3Av	0.93	2.56	3.4565 (13)	161
C12—H12A···O1Avi	0.93	2.55	3.4427 (13)	162

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3A—H1O3⋯O3Bi	0.82	1.63	2.4457 (11)	170
N3—H3A⋯O3Bii	0.86	2.14	2.9977 (12)	172
N3—H3B⋯O4Bi	0.86	2.07	2.8758 (12)	155
N2—H1N2⋯O4Aiii	0.85 (1)	1.99 (1)	2.7726 (12)	153 (1)
C2B—H2BA⋯O1Biv	0.93	2.52	3.2187 (13)	133
C8—H8A⋯O3Av	0.93	2.56	3.4565 (13)	161
C12—H12A⋯O1Avi	0.93	2.55	3.4427 (13)	162

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) ; (v) ; (vi) .