3-Cyano-anilinium hydrogen oxalate hemihydrate.

In the title hydrated mol-ecular salt, C(7)H(7)N(2) (+)·C(2)HO(4) (-)·0.5H(2)O, contains a 3-cyano-anilinium cation, a hydrogen oxalate anion and half a water mol-ecule in an asymmetric unit. The dihedral angle between the CO(2)(H) and CO(2) planes of the hydrogen oxalate ion is 7.96 (1)°. In the crystal, the components are linked by N-H⋯O and O-H⋯O hydrogen bonds, forming a layer lying parallel to the ac plane.

Related literature

For the properties of related compounds, see: Chen et al. (2000 ▶); Liu et al. (1999 ▶); Zhao et al. (2003 ▶). For the structures of related compounds, see: Dai & Chen (2011 ▶); Xu et al. (2011 ▶); Zheng (2011 ▶).

Experimental

Crystal data

C7H7N2 +·C2HO4 −·0.5H2O

M = 217.18

Monoclinic,

a = 15.1221 (7) Å

b = 5.6518 (1) Å

c = 13.6926 (6) Å

β = 113.22 (4)°

V = 1075.5 (3) Å3

Z = 4

Mo Kα radiation

μ = 0.11 mm−1

T = 173 K

0.10 × 0.05 × 0.05 mm

Data collection

Rigaku Mercury2 (2 × 2 bin mode) diffractometer

Absorption correction: multi-scan (CrystalClear; Rigaku, 2005 ▶) T min = 0.910, T max = 1.000

7209 measured reflections

2446 independent reflections

1906 reflections with I > 2σ(I)

R int = 0.034

Refinement

R[F 2 > 2σ(F 2)] = 0.054

wR(F 2) = 0.156

S = 1.07

2446 reflections

142 parameters

5 restraints

H-atom parameters constrained

Δρmax = 0.28 e Å−3

Δρmin = −0.24 e Å−3

Data collection: CrystalClear (Rigaku, 2005 ▶); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL.

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812019824/pv2542sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812019824/pv2542Isup2.hkl

Supplementary material file. DOI: 10.1107/S1600536812019824/pv2542Isup3.cml

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

C7H7N2+·C2HO4−·0.5H2O	F(000) = 452
Mr = 217.18	Dx = 1.341 Mg m−3
Monoclinic, P2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yc	Cell parameters from 2446 reflections
a = 15.1221 (7) Å	θ = 2.9–27.5°
b = 5.6518 (1) Å	µ = 0.11 mm−1
c = 13.6926 (6) Å	T = 173 K
β = 113.22 (4)°	Block, colorless
V = 1075.5 (3) Å3	0.10 × 0.05 × 0.05 mm
Z = 4

Rigaku Mercury2 (2x2 bin mode) diffractometer	2446 independent reflections
Radiation source: fine-focus sealed tube	1906 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.034
Detector resolution: 13.6612 pixels mm-1	θmax = 27.5°, θmin = 2.9°
CCD profile fitting scans	h = −18→19
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	k = −7→7
Tmin = 0.910, Tmax = 1.000	l = −17→17
7209 measured reflections

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)] = 0.054	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.156	H-atom parameters constrained
S = 1.07	w = 1/[σ2(Fo2) + (0.0872P)2 + 0.1364P] where P = (Fo2 + 2Fc2)/3
2446 reflections	(Δ/σ)max < 0.001
142 parameters	Δρmax = 0.28 e Å−3
5 restraints	Δρmin = −0.24 e Å−3

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
O1W	0.5000	0.3943 (3)	0.7500	0.0237 (4)
H1WA	0.4708	0.3063	0.6999	0.036*
N1	0.63809 (11)	0.7280 (2)	0.75668 (11)	0.0247 (4)
H1A	0.6328	0.8305	0.8034	0.037*
H1B	0.5962	0.6106	0.7469	0.037*
H1C	0.6258	0.8012	0.6952	0.037*
C1	0.73556 (13)	0.6324 (3)	0.79701 (14)	0.0278 (4)
C6	0.75806 (14)	0.4443 (3)	0.86683 (15)	0.0312 (4)
H6A	0.7120	0.3818	0.8888	0.037*
C5	0.85041 (16)	0.3490 (4)	0.90408 (18)	0.0449 (6)
C7	0.87338 (18)	0.1547 (5)	0.9797 (2)	0.0579 (7)
C3	0.8941 (2)	0.6365 (8)	0.8017 (3)	0.0843 (11)
H3A	0.9400	0.7024	0.7805	0.101*
C2	0.80292 (17)	0.7312 (5)	0.7645 (2)	0.0547 (7)
H2A	0.7870	0.8596	0.7183	0.066*
N2	0.89001 (19)	0.0051 (5)	1.0408 (2)	0.0826 (9)
C4	0.9188 (2)	0.4440 (7)	0.8704 (2)	0.0730 (9)
H4A	0.9802	0.3793	0.8937	0.088*
O1	0.60131 (9)	−0.0466 (2)	0.39238 (9)	0.0266 (3)
O2	0.60400 (10)	−0.1979 (2)	0.54425 (9)	0.0294 (3)
O3	0.60355 (10)	0.3895 (2)	0.46709 (9)	0.0302 (3)
H3	0.6034	0.5206	0.4927	0.045*
O4	0.62804 (10)	0.2420 (2)	0.62874 (9)	0.0298 (3)
C9	0.61454 (12)	0.2186 (3)	0.53599 (13)	0.0216 (4)
C8	0.60611 (12)	−0.0294 (3)	0.48550 (13)	0.0210 (4)

	U11	U22	U33	U12	U13	U23
O1W	0.0349 (10)	0.0193 (8)	0.0149 (8)	0.000	0.0076 (7)	0.000
N1	0.0353 (9)	0.0215 (7)	0.0201 (7)	−0.0007 (6)	0.0140 (6)	−0.0001 (6)
C1	0.0285 (10)	0.0333 (10)	0.0223 (8)	−0.0041 (7)	0.0107 (7)	−0.0045 (7)
C6	0.0315 (10)	0.0308 (10)	0.0305 (10)	−0.0006 (7)	0.0115 (8)	−0.0024 (8)
C5	0.0347 (12)	0.0507 (14)	0.0439 (13)	0.0079 (10)	0.0097 (9)	0.0010 (10)
C7	0.0420 (14)	0.0564 (16)	0.0646 (17)	0.0147 (11)	0.0097 (12)	0.0095 (14)
C3	0.0396 (16)	0.146 (3)	0.076 (2)	0.0062 (17)	0.0328 (15)	0.039 (2)
C2	0.0386 (13)	0.0800 (19)	0.0483 (14)	−0.0052 (11)	0.0200 (11)	0.0215 (13)
N2	0.0643 (16)	0.0727 (18)	0.092 (2)	0.0214 (13)	0.0107 (14)	0.0307 (15)
C4	0.0335 (14)	0.118 (3)	0.0714 (19)	0.0210 (15)	0.0244 (13)	0.0192 (19)
O1	0.0457 (8)	0.0193 (6)	0.0186 (6)	−0.0043 (5)	0.0168 (5)	−0.0029 (5)
O2	0.0541 (9)	0.0158 (6)	0.0209 (6)	−0.0013 (5)	0.0177 (6)	0.0005 (5)
O3	0.0592 (9)	0.0138 (6)	0.0219 (6)	−0.0003 (5)	0.0205 (6)	0.0005 (5)
O4	0.0505 (9)	0.0228 (7)	0.0177 (6)	−0.0020 (5)	0.0154 (5)	−0.0032 (5)
C9	0.0320 (9)	0.0166 (8)	0.0170 (8)	−0.0012 (6)	0.0105 (7)	0.0001 (6)
C8	0.0304 (9)	0.0158 (8)	0.0176 (8)	−0.0006 (6)	0.0104 (6)	0.0000 (6)

O1W—H1WA	0.8207	C3—C2	1.376 (4)
N1—C1	1.459 (2)	C3—C4	1.389 (5)
N1—H1A	0.8900	C3—H3A	0.9300
N1—H1B	0.8900	C2—H2A	0.9300
N1—H1C	0.8900	C4—H4A	0.9300
C1—C6	1.380 (3)	O1—C8	1.2521 (19)
C1—C2	1.380 (3)	O2—C8	1.255 (2)
C6—C5	1.392 (3)	O3—C9	1.314 (2)
C6—H6A	0.9300	O3—H3	0.8205
C5—C4	1.395 (4)	O4—C9	1.211 (2)
C5—C7	1.454 (4)	C9—C8	1.546 (2)
C7—N2	1.146 (4)
C1—N1—H1A	109.5	C2—C3—C4	121.2 (3)
C1—N1—H1B	109.5	C2—C3—H3A	119.4
H1A—N1—H1B	109.5	C4—C3—H3A	119.4
C1—N1—H1C	109.5	C3—C2—C1	118.8 (2)
H1A—N1—H1C	109.5	C3—C2—H2A	120.6
H1B—N1—H1C	109.5	C1—C2—H2A	120.6
C6—C1—C2	121.57 (19)	C3—C4—C5	119.3 (2)
C6—C1—N1	118.97 (16)	C3—C4—H4A	120.3
C2—C1—N1	119.46 (18)	C5—C4—H4A	120.3
C1—C6—C5	119.32 (19)	C9—O3—H3	112.2
C1—C6—H6A	120.3	O4—C9—O3	126.41 (15)
C5—C6—H6A	120.3	O4—C9—C8	121.21 (15)
C6—C5—C4	119.8 (2)	O3—C9—C8	112.36 (13)
C6—C5—C7	118.5 (2)	O1—C8—O2	125.99 (15)
C4—C5—C7	121.7 (2)	O1—C8—C9	119.18 (14)
N2—C7—C5	177.9 (3)	O2—C8—C9	114.83 (14)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WA···O1i	0.82	1.96	2.767 (2)	166
N1—H1A···O1ii	0.89	1.91	2.797 (2)	172
N1—H1C···O2iii	0.89	1.96	2.778 (2)	152
O3—H3···O2iii	0.82	1.74	2.559 (2)	178
N1—H1B···O1W	0.89	1.91	2.788 (2)	167

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H1WA⋯O1i	0.82	1.96	2.767 (2)	166
N1—H1A⋯O1ii	0.89	1.91	2.797 (2)	172
N1—H1C⋯O2iii	0.89	1.96	2.778 (2)	152
O3—H3⋯O2iii	0.82	1.74	2.559 (2)	178
N1—H1B⋯O1W	0.89	1.91	2.788 (2)	167

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