2-Amino-pyridinium 4-hydroxy-benzoate.

In the title compound, C(5)H(7)N(2) (+)·C(7)H(5)O(3) (-), the carboxyl-ate mean plane of the 4-hydroxy-benzoate anion is twisted by 8.78 (5)° from the attached ring. The cations and anions are linked via O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds, forming a three-dimensional network. In addition, π-π inter-actions involving the benzene and pyridinium rings, with centroid-centroid distances of 3.5500 (6) and 3.6594 (6) Å, are observed.

Related literature

For the applications of 2-amino­pyridine, see: Windholz (1976 ▶). For related structures, see: Chao et al. (1975 ▶); Heath et al. (1992 ▶); Jebas & Balasubramanian (2006 ▶); Joanna & Zaworotko (2005 ▶); Smith et al. (2000 ▶).

Experimental

Crystal data

C5H7N2 +·C7H5O3 −

M = 232.24

Monoclinic,

a = 10.0647 (2) Å

b = 10.9369 (2) Å

c = 10.7985 (2) Å

β = 111.036 (1)°

V = 1109.44 (4) Å3

Z = 4

Mo Kα radiation

μ = 0.10 mm−1

T = 100.0 (1) K

0.34 × 0.29 × 0.17 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T min = 0.966, T max = 0.983

22398 measured reflections

5078 independent reflections

3835 reflections with I > 2σ(I)

R int = 0.029

Refinement

R[F 2 > 2σ(F 2)] = 0.049

wR(F 2) = 0.140

S = 1.02

5078 reflections

158 parameters

1 restraint

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.50 e Å−3

Δρmin = −0.21 e Å−3

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: APEX2 and SAINT (Bruker, 2005 ▶); data reduction: SAINT; 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/S1600536808034934/ci2696sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808034934/ci2696Isup2.hkl

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

C5H7N2+·C7H5O3−	F(000) = 488
Mr = 232.24	Dx = 1.390 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 6837 reflections
a = 10.0647 (2) Å	θ = 2.8–35.6°
b = 10.9369 (2) Å	µ = 0.10 mm−1
c = 10.7985 (2) Å	T = 100 K
β = 111.036 (1)°	Block, colourless
V = 1109.44 (4) Å3	0.34 × 0.29 × 0.17 mm
Z = 4

Bruker SMART APEXII CCD area-detector diffractometer	5078 independent reflections
Radiation source: fine-focus sealed tube	3835 reflections with I > 2σ(I)
graphite	Rint = 0.030
φ and ω scans	θmax = 35.6°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −16→11
Tmin = 0.966, Tmax = 0.983	k = −17→17
22398 measured reflections	l = −16→17

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)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.140	H atoms treated by a mixture of independent and constrained refinement
S = 1.02	w = 1/[σ2(Fo2) + (0.0746P)2 + 0.2186P] where P = (Fo2 + 2Fc2)/3
5078 reflections	(Δ/σ)max = 0.001
158 parameters	Δρmax = 0.50 e Å−3
1 restraint	Δρmin = −0.21 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
O1	0.52173 (8)	0.67777 (7)	0.56764 (7)	0.02345 (16)
H1O1	0.5435	0.6430	0.6395	0.035*
O2	0.97943 (7)	1.10528 (6)	0.70095 (6)	0.01770 (14)
O3	0.88217 (8)	1.12535 (7)	0.48165 (6)	0.02051 (14)
N1	0.06716 (8)	0.30978 (7)	0.51061 (7)	0.01683 (15)
N2	0.18939 (9)	0.28645 (8)	0.73537 (8)	0.02239 (17)
H1N2	0.1354	0.2254	0.7348	0.027*
H2N2	0.2550	0.3085	0.8082	0.027*
C1	0.81342 (9)	0.89872 (8)	0.69825 (8)	0.01647 (16)
H1A	0.8873	0.9180	0.7769	0.020*
C2	0.72397 (10)	0.80096 (9)	0.69536 (8)	0.01740 (16)
H2A	0.7387	0.7548	0.7714	0.021*
C3	0.61195 (10)	0.77231 (9)	0.57782 (9)	0.01771 (16)
C4	0.59084 (11)	0.84236 (10)	0.46429 (9)	0.02258 (19)
H4A	0.5157	0.8243	0.3862	0.027*
C5	0.68141 (10)	0.93876 (9)	0.46745 (9)	0.02087 (18)
H5A	0.6673	0.9842	0.3910	0.025*
C6	0.79383 (9)	0.96844 (8)	0.58454 (8)	0.01518 (15)
C7	0.89111 (9)	1.07305 (8)	0.58888 (8)	0.01503 (15)
C8	0.03894 (10)	0.36798 (9)	0.39292 (9)	0.01886 (17)
H8A	−0.0348	0.3399	0.3183	0.023*
C9	0.11667 (11)	0.46682 (9)	0.38189 (10)	0.02141 (18)
H9A	0.0968	0.5068	0.3012	0.026*
C10	0.22817 (11)	0.50629 (9)	0.49691 (10)	0.02254 (19)
H10A	0.2836	0.5728	0.4919	0.027*
C11	0.25595 (10)	0.44821 (9)	0.61585 (10)	0.02098 (18)
H11A	0.3297	0.4750	0.6911	0.025*
C12	0.17140 (10)	0.34698 (9)	0.62328 (9)	0.01766 (16)
H1N1	0.0145 (17)	0.2453 (12)	0.5101 (19)	0.051 (5)*

	U11	U22	U33	U12	U13	U23
O1	0.0264 (4)	0.0269 (4)	0.0164 (3)	−0.0110 (3)	0.0069 (3)	0.0002 (3)
O2	0.0180 (3)	0.0203 (3)	0.0128 (3)	−0.0017 (2)	0.0032 (2)	−0.0020 (2)
O3	0.0219 (3)	0.0218 (3)	0.0143 (3)	−0.0048 (3)	0.0023 (2)	0.0040 (2)
N1	0.0170 (3)	0.0179 (3)	0.0144 (3)	−0.0029 (3)	0.0042 (3)	−0.0020 (3)
N2	0.0227 (4)	0.0254 (4)	0.0147 (3)	−0.0055 (3)	0.0015 (3)	−0.0015 (3)
C1	0.0167 (4)	0.0186 (4)	0.0127 (3)	−0.0001 (3)	0.0036 (3)	0.0001 (3)
C2	0.0189 (4)	0.0194 (4)	0.0136 (3)	−0.0011 (3)	0.0056 (3)	0.0016 (3)
C3	0.0192 (4)	0.0198 (4)	0.0151 (3)	−0.0037 (3)	0.0073 (3)	−0.0011 (3)
C4	0.0230 (4)	0.0288 (5)	0.0126 (3)	−0.0093 (4)	0.0024 (3)	0.0002 (3)
C5	0.0225 (4)	0.0245 (5)	0.0133 (3)	−0.0053 (3)	0.0036 (3)	0.0023 (3)
C6	0.0159 (3)	0.0164 (4)	0.0127 (3)	0.0000 (3)	0.0044 (3)	0.0002 (3)
C7	0.0154 (3)	0.0156 (4)	0.0129 (3)	0.0010 (3)	0.0037 (3)	0.0001 (3)
C8	0.0185 (4)	0.0218 (4)	0.0159 (4)	−0.0018 (3)	0.0057 (3)	−0.0008 (3)
C9	0.0226 (4)	0.0220 (4)	0.0206 (4)	−0.0025 (3)	0.0090 (3)	0.0011 (3)
C10	0.0210 (4)	0.0205 (4)	0.0276 (4)	−0.0052 (3)	0.0105 (4)	−0.0025 (3)
C11	0.0169 (4)	0.0213 (4)	0.0229 (4)	−0.0034 (3)	0.0049 (3)	−0.0046 (3)
C12	0.0162 (4)	0.0190 (4)	0.0163 (4)	−0.0005 (3)	0.0040 (3)	−0.0032 (3)

O1—C3	1.3543 (11)	C3—C4	1.3957 (13)
O1—H1O1	0.8200	C4—C5	1.3861 (13)
O2—C7	1.2675 (10)	C4—H4A	0.93
O3—C7	1.2654 (10)	C5—C6	1.3990 (12)
N1—C12	1.3528 (11)	C5—H5A	0.93
N1—C8	1.3571 (12)	C6—C7	1.4956 (12)
N1—H1N1	0.881 (9)	C8—C9	1.3644 (13)
N2—C12	1.3338 (12)	C8—H8A	0.93
N2—H1N2	0.86	C9—C10	1.4099 (14)
N2—H2N2	0.86	C9—H9A	0.93
C1—C2	1.3908 (13)	C10—C11	1.3687 (14)
C1—C6	1.3980 (12)	C10—H10A	0.93
C1—H1A	0.93	C11—C12	1.4161 (13)
C2—C3	1.3975 (12)	C11—H11A	0.93
C2—H2A	0.93
C3—O1—H1O1	109.5	C1—C6—C5	118.72 (8)
C12—N1—C8	122.35 (8)	C1—C6—C7	120.36 (8)
C12—N1—H1N1	121.1 (13)	C5—C6—C7	120.92 (8)
C8—N1—H1N1	116.5 (13)	O3—C7—O2	122.89 (8)
C12—N2—H1N2	120.0	O3—C7—C6	119.10 (7)
C12—N2—H2N2	120.0	O2—C7—C6	118.00 (7)
H1N2—N2—H2N2	120.0	N1—C8—C9	121.30 (9)
C2—C1—C6	120.90 (8)	N1—C8—H8A	119.3
C2—C1—H1A	119.5	C9—C8—H8A	119.3
C6—C1—H1A	119.5	C8—C9—C10	117.75 (9)
C1—C2—C3	119.83 (8)	C8—C9—H9A	121.1
C1—C2—H2A	120.1	C10—C9—H9A	121.1
C3—C2—H2A	120.1	C11—C10—C9	120.96 (9)
O1—C3—C4	117.49 (8)	C11—C10—H10A	119.5
O1—C3—C2	122.94 (8)	C9—C10—H10A	119.5
C4—C3—C2	119.57 (8)	C10—C11—C12	119.44 (9)
C5—C4—C3	120.30 (8)	C10—C11—H11A	120.3
C5—C4—H4A	119.9	C12—C11—H11A	120.3
C3—C4—H4A	119.9	N2—C12—N1	118.41 (8)
C4—C5—C6	120.67 (8)	N2—C12—C11	123.43 (8)
C4—C5—H5A	119.7	N1—C12—C11	118.17 (8)
C6—C5—H5A	119.7
C6—C1—C2—C3	−0.63 (14)	C5—C6—C7—O3	−8.78 (13)
C1—C2—C3—O1	179.36 (9)	C1—C6—C7—O2	−8.40 (12)
C1—C2—C3—C4	−0.07 (14)	C5—C6—C7—O2	171.26 (9)
O1—C3—C4—C5	−178.61 (9)	C12—N1—C8—C9	1.07 (14)
C2—C3—C4—C5	0.84 (15)	N1—C8—C9—C10	0.35 (14)
C3—C4—C5—C6	−0.92 (16)	C8—C9—C10—C11	−0.87 (15)
C2—C1—C6—C5	0.55 (13)	C9—C10—C11—C12	0.02 (15)
C2—C1—C6—C7	−179.78 (8)	C8—N1—C12—N2	178.22 (9)
C4—C5—C6—C1	0.22 (14)	C8—N1—C12—C11	−1.90 (14)
C4—C5—C6—C7	−179.44 (9)	C10—C11—C12—N2	−178.79 (9)
C1—C6—C7—O3	171.56 (8)	C10—C11—C12—N1	1.33 (14)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1O1···O2i	0.82	1.86	2.6257 (9)	154
N2—H1N2···O2ii	0.86	1.98	2.8224 (11)	167
N2—H2N2···O3iii	0.86	1.99	2.8396 (11)	171
N1—H1N1···O3ii	0.88 (1)	1.81 (1)	2.6861 (10)	169 (2)
C10—H10A···O1	0.93	2.51	3.3482 (14)	149
C11—H11A···O2i	0.93	2.34	3.1899 (12)	152

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1O1⋯O2i	0.82	1.86	2.6257 (9)	154
N2—H1N2⋯O2ii	0.86	1.98	2.8224 (11)	167
N2—H2N2⋯O3iii	0.86	1.99	2.8396 (11)	171
N1—H1N1⋯O3ii	0.88 (1)	1.81 (1)	2.6861 (10)	169 (2)
C10—H10A⋯O1	0.93	2.51	3.3482 (14)	149
C11—H11A⋯O2i	0.93	2.34	3.1899 (12)	152

Symmetry codes: (i) ; (ii) ; (iii) .