Bis(4-amino-pyridinium) bis(hydrogen oxalate) monohydrate.

In the title compound, 2C(5)H(7)N(2) (+)·2C(2)HO(4) (-)·H(2)O, the asymmetric unit consists of an amino-pyridinium cation, an oxalic actetate anion and a half-molecule of water, which lies on a two-fold rotation axis. The crystal packing is consolidated by inter-molecular O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds. The mol-ecules are linked into an infinite one dimensional chain along [010].

Related literature

For the biological activity of 4-amino­pyridine, see: Judge & Bever (2006 ▶); Schwid et al. (1997 ▶); Strupp et al. (2004 ▶). For the structure of oxalic acid, see: Derissen & Smith (1974 ▶). For related structures, see: Anderson et al. (2005 ▶); Bhattacharya et al. (1994 ▶); Chao & Schempp (1977 ▶); Karle et al. (2003 ▶). For stability of the temperature controller, see: Cosier & Glazer (1986 ▶).

Experimental

Crystal data

2C5H7N2 +·2C2HO4 −·H2O

M = 386.32

Monoclinic,

a = 15.6429 (6) Å

b = 5.6929 (2) Å

c = 19.9091 (7) Å

β = 105.617 (2)°

V = 1707.52 (11) Å3

Z = 4

Mo Kα radiation

μ = 0.13 mm−1

T = 100 K

0.49 × 0.34 × 0.11 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T min = 0.906, T max = 0.986

12438 measured reflections

2467 independent reflections

2159 reflections with I > 2σ(I)

R int = 0.027

Refinement

R[F 2 > 2σ(F 2)] = 0.034

wR(F 2) = 0.096

S = 1.03

2467 reflections

159 parameters

All H-atom parameters refined

Δρmax = 0.35 e Å−3

Δρmin = −0.24 e Å−3

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: 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, 2009 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809007247/at2732sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809007247/at2732Isup2.hkl

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

2C5H7N2+·2C2HO4−·H2O	F(000) = 808
Mr = 386.32	Dx = 1.503 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 7009 reflections
a = 15.6429 (6) Å	θ = 2.7–38.8°
b = 5.6929 (2) Å	µ = 0.13 mm−1
c = 19.9091 (7) Å	T = 100 K
β = 105.617 (2)°	Plate, colourless
V = 1707.52 (11) Å3	0.49 × 0.34 × 0.11 mm
Z = 4

Bruker SMART APEXII CCD area-detector diffractometer	2467 independent reflections
Radiation source: fine-focus sealed tube	2159 reflections with I > 2σ(I)
graphite	Rint = 0.027
φ and ω scans	θmax = 30.0°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −22→21
Tmin = 0.906, Tmax = 0.986	k = −7→7
12438 measured reflections	l = −27→28

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)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.096	All H-atom parameters refined
S = 1.03	w = 1/[σ2(Fo2) + (0.0564P)2 + 0.8323P] where P = (Fo2 + 2Fc2)/3
2467 reflections	(Δ/σ)max < 0.001
159 parameters	Δρmax = 0.35 e Å−3
0 restraints	Δρmin = −0.24 e Å−3

Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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	0.50462 (4)	−0.16951 (12)	0.39445 (3)	0.01643 (15)
O2	0.59652 (5)	−0.02380 (12)	0.49260 (3)	0.01700 (16)
O3	0.55682 (5)	0.41624 (12)	0.44228 (4)	0.02023 (17)
O4	0.45356 (5)	0.26647 (12)	0.35138 (3)	0.01903 (16)
N1	0.18206 (5)	0.86694 (16)	0.57611 (4)	0.01960 (18)
N2	0.39056 (6)	1.06075 (16)	0.74035 (4)	0.01829 (17)
C1	0.20886 (7)	0.72101 (18)	0.63132 (5)	0.0199 (2)
C2	0.27784 (6)	0.77998 (18)	0.68707 (5)	0.01844 (19)
C3	0.32276 (6)	0.99712 (16)	0.68737 (5)	0.01467 (18)
C4	0.29134 (6)	1.14587 (17)	0.62850 (5)	0.01667 (19)
C5	0.22175 (6)	1.07631 (18)	0.57489 (5)	0.0188 (2)
C6	0.54297 (6)	0.00122 (16)	0.43617 (4)	0.01357 (17)
C7	0.51411 (6)	0.25017 (16)	0.40655 (5)	0.01471 (18)
O1W	0.5000	0.46896 (19)	0.7500	0.0215 (2)
H2W1	0.5135 (12)	0.560 (3)	0.7190 (9)	0.048 (5)*
H1	0.1765 (9)	0.574 (3)	0.6285 (7)	0.028 (3)*
H2	0.2966 (9)	0.673 (3)	0.7268 (8)	0.029 (4)*
H4	0.3195 (9)	1.295 (3)	0.6250 (7)	0.023 (3)*
H5	0.1983 (9)	1.169 (2)	0.5344 (7)	0.021 (3)*
H1N2	0.4086 (10)	0.968 (3)	0.7766 (8)	0.028 (4)*
H2N2	0.4168 (9)	1.197 (3)	0.7367 (7)	0.025 (3)*
H1N1	0.1413 (11)	0.823 (3)	0.5397 (9)	0.038 (4)*
H1O1	0.5253 (12)	−0.327 (4)	0.4140 (9)	0.054 (5)*

	U11	U22	U33	U12	U13	U23
O1	0.0207 (3)	0.0102 (3)	0.0151 (3)	0.0000 (2)	−0.0007 (2)	−0.0013 (2)
O2	0.0197 (3)	0.0137 (3)	0.0141 (3)	0.0009 (2)	−0.0014 (3)	0.0004 (2)
O3	0.0259 (4)	0.0109 (3)	0.0186 (3)	−0.0014 (2)	−0.0033 (3)	−0.0011 (2)
O4	0.0249 (4)	0.0141 (3)	0.0136 (3)	0.0010 (2)	−0.0027 (3)	0.0007 (2)
N1	0.0176 (4)	0.0215 (4)	0.0160 (4)	−0.0005 (3)	−0.0017 (3)	−0.0030 (3)
N2	0.0178 (4)	0.0182 (4)	0.0152 (4)	−0.0017 (3)	−0.0019 (3)	0.0011 (3)
C1	0.0196 (4)	0.0165 (5)	0.0221 (5)	−0.0023 (3)	0.0031 (4)	−0.0012 (3)
C2	0.0192 (4)	0.0166 (4)	0.0176 (4)	−0.0011 (3)	0.0017 (3)	0.0028 (3)
C3	0.0149 (4)	0.0143 (4)	0.0140 (4)	0.0012 (3)	0.0022 (3)	−0.0006 (3)
C4	0.0177 (4)	0.0143 (4)	0.0165 (4)	0.0008 (3)	0.0019 (3)	0.0017 (3)
C5	0.0182 (4)	0.0205 (5)	0.0152 (4)	0.0032 (3)	0.0002 (3)	0.0025 (3)
C6	0.0158 (4)	0.0112 (4)	0.0133 (4)	−0.0001 (3)	0.0032 (3)	−0.0002 (3)
C7	0.0188 (4)	0.0112 (4)	0.0132 (4)	0.0003 (3)	0.0027 (3)	0.0002 (3)
O1W	0.0307 (6)	0.0146 (5)	0.0188 (5)	0.000	0.0061 (4)	0.000

O1—C6	1.3139 (11)	C1—C2	1.3654 (13)
O1—H1O1	1.00 (2)	C1—H1	0.973 (15)
O2—C6	1.2155 (11)	C2—C3	1.4211 (13)
O3—C7	1.2611 (11)	C2—H2	0.979 (15)
O4—C7	1.2458 (11)	C3—C4	1.4221 (12)
N1—C5	1.3471 (14)	C4—C5	1.3621 (13)
N1—C1	1.3514 (13)	C4—H4	0.966 (15)
N1—H1N1	0.863 (17)	C5—H5	0.951 (13)
N2—C3	1.3291 (12)	C6—C7	1.5547 (13)
N2—H1N2	0.877 (15)	O1W—H2W1	0.874 (18)
N2—H2N2	0.890 (16)
C6—O1—H1O1	111.9 (11)	N2—C3—C4	121.12 (9)
C5—N1—C1	121.00 (8)	C2—C3—C4	116.98 (8)
C5—N1—H1N1	118.7 (11)	C5—C4—C3	119.91 (9)
C1—N1—H1N1	120.2 (11)	C5—C4—H4	118.8 (8)
C3—N2—H1N2	120.1 (10)	C3—C4—H4	121.3 (8)
C3—N2—H2N2	117.4 (9)	N1—C5—C4	121.21 (9)
H1N2—N2—H2N2	122.5 (13)	N1—C5—H5	115.6 (8)
N1—C1—C2	120.95 (9)	C4—C5—H5	123.2 (9)
N1—C1—H1	116.1 (8)	O2—C6—O1	125.55 (8)
C2—C1—H1	123.0 (8)	O2—C6—C7	121.00 (8)
C1—C2—C3	119.93 (9)	O1—C6—C7	113.45 (7)
C1—C2—H2	120.2 (9)	O4—C7—O3	127.09 (8)
C3—C2—H2	119.9 (9)	O4—C7—C6	118.46 (8)
N2—C3—C2	121.90 (9)	O3—C7—C6	114.44 (8)
C5—N1—C1—C2	−0.98 (15)	C1—N1—C5—C4	1.41 (15)
N1—C1—C2—C3	−0.29 (15)	C3—C4—C5—N1	−0.56 (15)
C1—C2—C3—N2	−179.57 (9)	O2—C6—C7—O4	−173.95 (8)
C1—C2—C3—C4	1.08 (14)	O1—C6—C7—O4	6.47 (12)
N2—C3—C4—C5	179.98 (9)	O2—C6—C7—O3	6.58 (13)
C2—C3—C4—C5	−0.67 (14)	O1—C6—C7—O3	−173.00 (8)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H2W1···O4i	0.874 (18)	1.895 (18)	2.7676 (9)	175.0 (18)
N2—H1N2···O4ii	0.877 (15)	1.983 (16)	2.8556 (11)	173.4 (14)
N2—H2N2···O1Wiii	0.890 (16)	1.993 (15)	2.8620 (12)	164.8 (13)
N1—H1N1···O3iv	0.863 (17)	2.100 (17)	2.8645 (11)	147.3 (15)
N1—H1N1···O2iv	0.863 (17)	2.218 (17)	2.8818 (11)	133.6 (15)
O1—H1O1···O3v	1.00 (2)	1.60 (2)	2.5916 (10)	177.6 (18)
C5—H5···O2vi	0.951 (13)	2.361 (14)	3.1585 (12)	141.2 (11)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H2W1⋯O4i	0.874 (18)	1.895 (18)	2.7676 (9)	175.0 (18)
N2—H1N2⋯O4ii	0.877 (15)	1.983 (16)	2.8556 (11)	173.4 (14)
N2—H2N2⋯O1Wiii	0.890 (16)	1.993 (15)	2.8620 (12)	164.8 (13)
N1—H1N1⋯O3iv	0.863 (17)	2.100 (17)	2.8645 (11)	147.3 (15)
N1—H1N1⋯O2iv	0.863 (17)	2.218 (17)	2.8818 (11)	133.6 (15)
O1—H1O1⋯O3v	1.00 (2)	1.60 (2)	2.5916 (10)	177.6 (18)
C5—H5⋯O2vi	0.951 (13)	2.361 (14)	3.1585 (12)	141.2 (11)

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