4-Chloro-anilinium hydrogen oxalate hemihydrate.

In the title hydrated mol-ecular salt, C(6)H(7)ClN(+)·C(2)HO(4) (-)·0.5H(2)O, the water O atom lies on a crystallographic twofold axis. In the crystal, the anions are linked by O-H⋯O hydrogen bonds, forming chains propagating along the b axis. These chains are inter-connected through O-H⋯O hydrogen bonds from the water mol-ecules and N-H⋯O hydrogen bonds from the cations, building layers parallel to the ab plane.

Related literature

For background to supra­molecular networks, see: Subramanian & Zawarotko (1994 ▶). For related structures, see: Akriche & Rzaigui (2009 ▶); Dhaouadi et al. (2008 ▶).

Experimental

Crystal data

C6H7ClN+·C2HO4 −·0.5H2O

M = 226.61

Monoclinic,

a = 26.739 (2) Å

b = 5.701 (3) Å

c = 13.859 (2) Å

β = 111.02 (3)°

V = 1972.0 (11) Å3

Z = 8

Ag Kα radiation

λ = 0.56085 Å

μ = 0.20 mm−1

T = 293 K

0.30 × 0.20 × 0.20 mm

Data collection

Enraf–Nonius TurboCAD-4 diffractometer

5686 measured reflections

4806 independent reflections

2341 reflections with I > 2σ(I)

R int = 0.021

2 standard reflections every 120 min intensity decay: 5%

Refinement

R[F 2 > 2σ(F 2)] = 0.061

wR(F 2) = 0.174

S = 1.01

4806 reflections

136 parameters

H-atom parameters not refined

Δρmax = 0.41 e Å−3

Δρmin = −0.52 e Å−3

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994 ▶); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 (Farrugia, 1997 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053681001144X/hb5378sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053681001144X/hb5378Isup2.hkl

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

C6H7ClN+·C2HO4−·0.5H2O	F(000) = 936
Mr = 226.61	Dx = 1.527 Mg m−3
Monoclinic, C2/c	Ag Kα radiation, λ = 0.56085 Å
Hall symbol: -C 2yc	Cell parameters from 25 reflections
a = 26.739 (2) Å	θ = 9–11°
b = 5.701 (3) Å	µ = 0.20 mm−1
c = 13.859 (2) Å	T = 293 K
β = 111.02 (3)°	Block, pink
V = 1972.0 (11) Å3	0.30 × 0.20 × 0.20 mm
Z = 8

Enraf–Nonius TurboCAD-4 diffractometer	Rint = 0.021
Radiation source: fine-focus sealed tube	θmax = 28.0°, θmin = 2.4°
graphite	h = −5→44
non–profiled ω scans	k = 0→9
5686 measured reflections	l = −23→22
4806 independent reflections	2 standard reflections every 120 min
2341 reflections with I > 2σ(I)	intensity decay: 5%

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)] = 0.061	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.174	H-atom parameters not refined
S = 1.01	w = 1/[σ2(Fo2) + (0.0711P)2 + 0.8804P] where P = (Fo2 + 2Fc2)/3
4806 reflections	(Δ/σ)max < 0.001
136 parameters	Δρmax = 0.41 e Å−3
0 restraints	Δρmin = −0.52 e Å−3

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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
H1	0.5152 (9)	0.705 (4)	0.2959 (17)	0.047 (7)*
Cl1	0.19472 (2)	0.44325 (17)	0.06451 (5)	0.0743 (3)
O5	0.5000	0.6144 (3)	0.2500	0.0321 (4)
O2	0.44106 (6)	0.1863 (2)	0.46326 (9)	0.0360 (3)
C7	0.44211 (7)	0.0194 (3)	0.52200 (12)	0.0249 (3)
O3	0.44333 (6)	−0.3952 (2)	0.54031 (10)	0.0405 (3)
H3	0.4408	−0.5227	0.5116	0.061*
C8	0.43716 (6)	−0.2276 (3)	0.47280 (12)	0.0254 (3)
O1	0.44687 (6)	0.0354 (2)	0.61417 (9)	0.0401 (3)
N1	0.42789 (6)	0.2638 (3)	0.25679 (11)	0.0304 (3)
H1A	0.4460	0.3837	0.2442	0.046*
H1B	0.4353	0.1338	0.2289	0.046*
H1C	0.4374	0.2445	0.3248	0.046*
O4	0.42904 (6)	−0.2531 (2)	0.38251 (9)	0.0389 (3)
C1	0.37061 (7)	0.3117 (3)	0.21167 (12)	0.0299 (3)
C6	0.35291 (8)	0.5162 (4)	0.15786 (16)	0.0430 (5)
H6	0.3773	0.6259	0.1516	0.052*
C4	0.26302 (8)	0.3917 (5)	0.12275 (15)	0.0463 (5)
C2	0.33516 (9)	0.1479 (4)	0.22190 (16)	0.0449 (5)
H2	0.3477	0.0105	0.2588	0.054*
C5	0.29834 (9)	0.5574 (4)	0.11304 (19)	0.0522 (6)
H5	0.2857	0.6955	0.0768	0.063*
C3	0.28077 (9)	0.1887 (5)	0.17710 (18)	0.0523 (6)
H3A	0.2564	0.0793	0.1838	0.063*

	U11	U22	U33	U12	U13	U23
Cl1	0.0367 (3)	0.1244 (7)	0.0581 (4)	0.0117 (3)	0.0125 (2)	−0.0091 (4)
O5	0.0451 (10)	0.0241 (8)	0.0239 (8)	0.000	0.0084 (7)	0.000
O2	0.0605 (8)	0.0192 (5)	0.0290 (6)	−0.0017 (6)	0.0167 (6)	0.0022 (4)
C7	0.0327 (7)	0.0186 (6)	0.0235 (6)	−0.0026 (6)	0.0102 (6)	−0.0021 (5)
O3	0.0757 (10)	0.0167 (5)	0.0308 (6)	−0.0014 (6)	0.0212 (7)	0.0012 (4)
C8	0.0325 (8)	0.0186 (6)	0.0243 (7)	−0.0015 (6)	0.0094 (6)	−0.0005 (5)
O1	0.0714 (9)	0.0255 (6)	0.0286 (6)	−0.0124 (6)	0.0243 (6)	−0.0070 (5)
N1	0.0357 (7)	0.0295 (7)	0.0264 (6)	0.0009 (6)	0.0117 (6)	0.0000 (5)
O4	0.0616 (9)	0.0292 (6)	0.0242 (5)	0.0026 (6)	0.0134 (6)	−0.0036 (5)
C1	0.0354 (8)	0.0305 (8)	0.0235 (7)	0.0009 (7)	0.0102 (6)	−0.0026 (6)
C6	0.0426 (10)	0.0331 (9)	0.0466 (11)	−0.0019 (8)	0.0079 (8)	0.0051 (8)
C4	0.0343 (9)	0.0695 (15)	0.0343 (9)	0.0042 (10)	0.0112 (7)	−0.0095 (10)
C2	0.0476 (11)	0.0448 (11)	0.0454 (11)	−0.0042 (9)	0.0207 (9)	0.0099 (9)
C5	0.0462 (12)	0.0451 (12)	0.0532 (12)	0.0098 (10)	0.0031 (10)	0.0055 (10)
C3	0.0443 (11)	0.0651 (15)	0.0511 (12)	−0.0100 (11)	0.0216 (10)	0.0033 (11)

Cl1—C4	1.736 (2)	N1—H1C	0.8900
O5—H1	0.81 (2)	C1—C6	1.374 (3)
O2—C7	1.2460 (19)	C1—C2	1.373 (3)
C7—O1	1.2407 (19)	C6—C5	1.385 (3)
C7—C8	1.549 (2)	C6—H6	0.9300
O3—C8	1.3055 (19)	C4—C3	1.370 (3)
O3—H3	0.8200	C4—C5	1.376 (4)
C8—O4	1.1996 (19)	C2—C3	1.381 (3)
N1—C1	1.457 (2)	C2—H2	0.9300
N1—H1A	0.8900	C5—H5	0.9300
N1—H1B	0.8900	C3—H3A	0.9300
O1—C7—O2	125.89 (15)	C1—C6—C5	119.3 (2)
O1—C7—C8	118.75 (14)	C1—C6—H6	120.3
O2—C7—C8	115.36 (13)	C5—C6—H6	120.3
C8—O3—H3	109.5	C3—C4—C5	121.3 (2)
O4—C8—O3	126.01 (15)	C3—C4—Cl1	119.84 (19)
O4—C8—C7	121.60 (14)	C5—C4—Cl1	118.87 (19)
O3—C8—C7	112.39 (13)	C1—C2—C3	119.6 (2)
C1—N1—H1A	109.5	C1—C2—H2	120.2
C1—N1—H1B	109.5	C3—C2—H2	120.2
H1A—N1—H1B	109.5	C4—C5—C6	119.3 (2)
C1—N1—H1C	109.5	C4—C5—H5	120.3
H1A—N1—H1C	109.5	C6—C5—H5	120.3
H1B—N1—H1C	109.5	C4—C3—C2	119.4 (2)
C6—C1—C2	121.13 (18)	C4—C3—H3A	120.3
C6—C1—N1	119.76 (16)	C2—C3—H3A	120.3
C2—C1—N1	119.09 (16)

D—H···A	D—H	H···A	D···A	D—H···A
O5—H1···O1i	0.81 (2)	1.97 (2)	2.762 (2)	169 (2)
O3—H3···O2ii	0.82	1.79	2.606 (2)	173
N1—H1A···O5	0.89	1.93	2.802 (3)	165
N1—H1B···O1iii	0.89	1.98	2.792 (3)	151
N1—H1C···O2	0.89	1.92	2.790 (2)	167

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O5—H1⋯O1i	0.81 (2)	1.97 (2)	2.762 (2)	169 (2)
O3—H3⋯O2ii	0.82	1.79	2.606 (2)	173
N1—H1A⋯O5	0.89	1.93	2.802 (3)	165
N1—H1B⋯O1iii	0.89	1.98	2.792 (3)	151
N1—H1C⋯O2	0.89	1.92	2.790 (2)	167

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