Crystal structure of 3,4-di­chloro­anilinium hydrogen phthalate

In the title salt, C₆H₆Cl₂N⁺·C₈H₅O₄⁻, the carb­oxy­lic acid and carboxyl­ate groups of the anion form dihedral angles of 20.79 (19) and 74.76 (14)°, respectively, with the plane of the benzene ring. In the crystal, mol­ecules are assembled into a two-dimensional polymeric network parallel to (100) via N—H...O and O—H...O hydrogen bonds. In addition, within the layer, there are π–π stacking inter­actions between the benzene rings of the cation and the anion [centroid–centroid distance = 3.6794 (17) Å]. A weak C—H...O interaction is also observed.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.049
• wR factor = 0.133
• Data-to-parameter ratio = 16.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT340_ALERT_3_C Low Bond Precision on  C-C Bonds ...............     0.0041 Ang.
PLAT905_ALERT_3_C Negative K value in the Analysis of Variance ...     -0.674 Report
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          9 Report

Alert level G
PLAT007_ALERT_5_G Number of Unrefined Donor-H Atoms ..............          4 Report
PLAT066_ALERT_1_G Predicted and Reported Tmin&Tmax Range Identical          ? Check
PLAT910_ALERT_3_G Missing # of FCF Reflection(s) Below Th(Min) ...          2 Report

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   3 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   3 ALERT level G = General information/check it is not something unexpected

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   4 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

The crystal structures of 4-bromoanilinium hydrogen phthalate (Liang, 2011), (R,S)-α-phenylethylammonium hydrogen phthalate (Kozma et al., 1994), 4-chloroanilinium hydrogen phthalate (Jagan & Sivakumar, 2009), 3-hydroxyanilinium hydrogen phthalate (Jagan & Sivakumar, 2009), 2-hydroxyanilinium hydrogen phthalate (Jagan & Sivakumar, 2009), 3-Methylanilinium 2-carboxybenzoate (Liu, 2012) and 4-ethoxyanilinium 2- carboxybenzoate (Jagan & Sivakumar, 2011) have been published which are related to the title compound (I, Fig. 1). (I) is synthesized for the study of co-crystallization.

In (I) the benzene ring A (C2—C7) of the phathalate anion is planar with r.m.s. deviation of 0.0024 Å. The carboxylic B (C1/O1/O2) and carboxylate C (C8/O3/O4) groups are oriented at a dihedral angle of 20.79 (19)° and 74.76 (14)°, respectively, with the parent benzene ring A. The molecules form a two dimensional polymeric network parallel to (100) due to N—H···O and O—H···O hydrogen bonds (Table 1, Fig.2). There exist π···π interaction between Cg11···Cg21ⁱ [i = x, y, z] with centroid-centroid distance of 3.6794 (17) Å, where Cg1 and Cg2 are the centroids of the benzene rings A and E (C9—C14). The topology of two-dimensional hydrogen-bond network in the title compound is the same as in 4-chloroanilinium salt (Jagan & Sivakumar, 2009).

Related literature

For related structures, see: Jagan & Sivakumar (2009, 2011); Kozma et al. (1994); Liang et al. (2011); Liu (2012).

S2. Experimental

Equimolar quantities of phathalic acid (0.831 g, 5 mmol) and 3,4-dichloroaniline (0.810 g, 5 mmol) were refluxed in 20 ml of methanol for 2 h. The solution was kept at room temperature and colorless plates appeared after two days (m.p. 422–423 K).

S3. Refinement

The H atoms were positioned geometrically (C–H = 0.93 Å, N–H = 0.89 Å, O—H = 0.82 Å) and refined as riding with U_iso(H) = xU_eq (C, N, O), where x = 1.5 for NH₃ and hydroxy and x =1.2 for aromatic H-atoms.

Computing details

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Figures

	Fig. 1. View of the title compound with the atom numbering scheme. The displacement ellipsoids are drawn at the 50% probability level. H-atoms are shown as small circles of arbitrary radii.
	Fig. 2. The packing (PLATON; Spek, 2009) of two-dimensional (100) polymeric networks.
	Fig. 3. Hydrogen bonds within (100) layer.

3,4-Dichloroanilinium 2-carboxybenzoate

Crystal data

C6H6Cl2N^+·C8H5O4^−	F(000) = 1344
Mr = 328.14	Dx = 1.459 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 29.694 (5) Å	Cell parameters from 1849 reflections
b = 7.7536 (13) Å	θ = 2.8–27.0°
c = 13.125 (2) Å	µ = 0.45 mm^−1
β = 98.673 (12)°	T = 296 K
V = 2987.3 (9) Å^3	Plate, colorless
Z = 8	0.34 × 0.28 × 0.16 mm

Data collection

Bruker Kappa APEXII CCD diffractometer	3248 independent reflections
Radiation source: fine-focus sealed tube	1849 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.051
Detector resolution: 7.80 pixels mm^-1	θmax = 27.0°, θmin = 2.8°
ω scans	h = −37→37
Absorption correction: multi-scan (SADABS; Bruker, 2005)	k = −9→9
Tmin = 0.860, Tmax = 0.935	l = −15→16
11652 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.133	H-atom parameters constrained
S = 1.02	w = 1/[σ^2(Fo^2) + (0.0503P)^2 + 2.3478P] where P = (Fo^2 + 2Fc^2)/3
3248 reflections	(Δ/σ)max < 0.001
192 parameters	Δρmax = 0.23 e Å^−3
0 restraints	Δρmin = −0.26 e Å^−3

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.21968 (8)	0.5928 (3)	0.41451 (18)	0.0727 (7)
O2	0.23502 (6)	0.8002 (2)	0.30759 (13)	0.0427 (5)
H2	0.2590	0.7471	0.3096	0.064*
O3	0.21509 (6)	1.1573 (2)	0.37561 (12)	0.0417 (5)
O4	0.19151 (5)	1.1301 (2)	0.20757 (12)	0.0377 (4)
C1	0.20865 (9)	0.7204 (4)	0.3646 (2)	0.0416 (7)
C2	0.16278 (8)	0.8021 (4)	0.35827 (18)	0.0379 (6)
C3	0.15350 (8)	0.9708 (4)	0.32373 (16)	0.0340 (6)
C4	0.10931 (9)	1.0324 (4)	0.3140 (2)	0.0476 (7)
H4	0.1029	1.1443	0.2907	0.057*
C5	0.07466 (10)	0.9285 (5)	0.3386 (2)	0.0575 (9)
H5	0.0451	0.9709	0.3316	0.069*
C6	0.08358 (10)	0.7643 (5)	0.3731 (2)	0.0654 (10)
H6	0.0601	0.6957	0.3900	0.078*
C7	0.12732 (10)	0.6995 (4)	0.3830 (2)	0.0533 (8)
H7	0.1332	0.5872	0.4063	0.064*
C8	0.18979 (8)	1.0937 (3)	0.30026 (18)	0.0324 (6)
Cl1	0.03331 (3)	0.83295 (14)	0.06616 (8)	0.0831 (4)
Cl2	0.04230 (3)	0.44073 (16)	0.13559 (9)	0.0970 (4)
N1	0.20521 (7)	0.8466 (3)	0.07778 (14)	0.0374 (5)
H1A	0.2041	0.9466	0.1106	0.056*
H1B	0.2057	0.8662	0.0111	0.056*
H1C	0.2303	0.7895	0.1043	0.056*
C9	0.16540 (8)	0.7446 (4)	0.08969 (16)	0.0334 (6)
C10	0.12353 (8)	0.8247 (4)	0.07404 (18)	0.0396 (6)
H10	0.1211	0.9403	0.0551	0.047*
C11	0.08537 (9)	0.7318 (4)	0.0867 (2)	0.0496 (8)
C12	0.08933 (9)	0.5597 (5)	0.1155 (2)	0.0530 (8)
C13	0.13137 (10)	0.4807 (4)	0.1296 (2)	0.0526 (8)
H13	0.1339	0.3649	0.1480	0.063*
C14	0.16975 (9)	0.5740 (4)	0.1163 (2)	0.0440 (7)
H14	0.1982	0.5214	0.1253	0.053*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0725 (15)	0.0638 (16)	0.0883 (17)	0.0207 (12)	0.0337 (12)	0.0404 (14)
O2	0.0415 (10)	0.0463 (12)	0.0432 (10)	0.0097 (9)	0.0159 (9)	0.0077 (9)
O3	0.0421 (10)	0.0544 (13)	0.0293 (9)	−0.0072 (9)	0.0077 (8)	−0.0073 (9)
O4	0.0425 (10)	0.0423 (12)	0.0297 (9)	−0.0029 (8)	0.0099 (7)	0.0012 (8)
C1	0.0494 (16)	0.0422 (18)	0.0352 (14)	0.0016 (14)	0.0130 (12)	0.0024 (13)
C2	0.0431 (15)	0.0443 (17)	0.0289 (13)	−0.0027 (13)	0.0134 (11)	0.0022 (12)
C3	0.0350 (13)	0.0466 (18)	0.0215 (12)	−0.0019 (12)	0.0081 (10)	−0.0032 (11)
C4	0.0389 (15)	0.060 (2)	0.0461 (16)	0.0032 (14)	0.0129 (12)	0.0022 (14)
C5	0.0377 (16)	0.079 (3)	0.0589 (19)	−0.0002 (16)	0.0161 (14)	0.0029 (18)
C6	0.0465 (18)	0.087 (3)	0.067 (2)	−0.0160 (19)	0.0239 (15)	0.001 (2)
C7	0.0604 (19)	0.054 (2)	0.0493 (17)	−0.0114 (16)	0.0211 (14)	0.0061 (15)
C8	0.0333 (13)	0.0358 (15)	0.0297 (13)	0.0046 (11)	0.0103 (10)	−0.0041 (11)
Cl1	0.0388 (4)	0.1064 (9)	0.1041 (7)	0.0154 (5)	0.0106 (4)	0.0168 (6)
Cl2	0.0625 (6)	0.1052 (9)	0.1236 (9)	−0.0304 (6)	0.0149 (5)	0.0246 (7)
N1	0.0389 (12)	0.0462 (15)	0.0275 (10)	0.0019 (10)	0.0061 (9)	−0.0017 (10)
C9	0.0376 (14)	0.0429 (17)	0.0205 (11)	−0.0011 (12)	0.0069 (10)	−0.0035 (11)
C10	0.0409 (15)	0.0439 (18)	0.0344 (13)	0.0058 (13)	0.0074 (11)	0.0020 (12)
C11	0.0374 (15)	0.067 (2)	0.0450 (16)	0.0050 (15)	0.0073 (12)	0.0014 (15)
C12	0.0451 (17)	0.065 (2)	0.0493 (17)	−0.0126 (16)	0.0076 (13)	0.0005 (16)
C13	0.060 (2)	0.0458 (19)	0.0521 (17)	−0.0053 (16)	0.0104 (14)	0.0020 (15)
C14	0.0440 (16)	0.0467 (19)	0.0412 (15)	0.0064 (14)	0.0057 (12)	−0.0002 (13)

Geometric parameters (Å, º)

O1—C1	1.204 (3)	C7—H7	0.9300
O2—C1	1.316 (3)	Cl1—C11	1.718 (3)
O2—H2	0.8200	Cl2—C12	1.726 (3)
O3—C8	1.250 (3)	N1—C9	1.450 (3)
O4—C8	1.257 (3)	N1—H1A	0.8900
C1—C2	1.493 (4)	N1—H1B	0.8900
C2—C7	1.396 (4)	N1—H1C	0.8900
C2—C3	1.398 (4)	C9—C14	1.369 (4)
C3—C4	1.384 (3)	C9—C10	1.377 (3)
C3—C8	1.505 (3)	C10—C11	1.374 (4)
C4—C5	1.383 (4)	C10—H10	0.9300
C4—H4	0.9300	C11—C12	1.388 (5)
C5—C6	1.364 (5)	C12—C13	1.378 (4)
C5—H5	0.9300	C13—C14	1.383 (4)
C6—C7	1.380 (4)	C13—H13	0.9300
C6—H6	0.9300	C14—H14	0.9300
C1—O2—H2	109.5	C9—N1—H1A	109.5
O1—C1—O2	124.0 (3)	C9—N1—H1B	109.5
O1—C1—C2	123.3 (2)	H1A—N1—H1B	109.5
O2—C1—C2	112.6 (2)	C9—N1—H1C	109.5
C7—C2—C3	119.3 (3)	H1A—N1—H1C	109.5
C7—C2—C1	117.3 (3)	H1B—N1—H1C	109.5
C3—C2—C1	123.2 (2)	C14—C9—C10	121.5 (2)
C4—C3—C2	119.4 (2)	C14—C9—N1	120.5 (2)
C4—C3—C8	117.4 (3)	C10—C9—N1	118.1 (2)
C2—C3—C8	123.1 (2)	C11—C10—C9	119.2 (3)
C5—C4—C3	120.4 (3)	C11—C10—H10	120.4
C5—C4—H4	119.8	C9—C10—H10	120.4
C3—C4—H4	119.8	C10—C11—C12	120.0 (3)
C6—C5—C4	120.5 (3)	C10—C11—Cl1	118.7 (3)
C6—C5—H5	119.8	C12—C11—Cl1	121.3 (2)
C4—C5—H5	119.8	C13—C12—C11	120.1 (3)
C5—C6—C7	120.3 (3)	C13—C12—Cl2	118.7 (3)
C5—C6—H6	119.9	C11—C12—Cl2	121.2 (2)
C7—C6—H6	119.9	C12—C13—C14	119.9 (3)
C6—C7—C2	120.2 (3)	C12—C13—H13	120.1
C6—C7—H7	119.9	C14—C13—H13	120.1
C2—C7—H7	119.9	C9—C14—C13	119.3 (3)
O3—C8—O4	124.7 (2)	C9—C14—H14	120.3
O3—C8—C3	116.8 (2)	C13—C14—H14	120.3
O4—C8—C3	118.4 (2)
O1—C1—C2—C7	−20.8 (4)	C2—C3—C8—O3	−74.5 (3)
O2—C1—C2—C7	157.5 (2)	C4—C3—C8—O4	−74.4 (3)
O1—C1—C2—C3	162.9 (3)	C2—C3—C8—O4	108.1 (3)
O2—C1—C2—C3	−18.9 (4)	C14—C9—C10—C11	0.8 (4)
C7—C2—C3—C4	−0.5 (4)	N1—C9—C10—C11	−178.8 (2)
C1—C2—C3—C4	175.8 (2)	C9—C10—C11—C12	0.4 (4)
C7—C2—C3—C8	176.9 (2)	C9—C10—C11—Cl1	−179.63 (18)
C1—C2—C3—C8	−6.8 (4)	C10—C11—C12—C13	−1.3 (4)
C2—C3—C4—C5	0.3 (4)	Cl1—C11—C12—C13	178.8 (2)
C8—C3—C4—C5	−177.2 (2)	C10—C11—C12—Cl2	178.2 (2)
C3—C4—C5—C6	0.2 (4)	Cl1—C11—C12—Cl2	−1.8 (4)
C4—C5—C6—C7	−0.5 (5)	C11—C12—C13—C14	0.9 (4)
C5—C6—C7—C2	0.3 (5)	Cl2—C12—C13—C14	−178.6 (2)
C3—C2—C7—C6	0.2 (4)	C10—C9—C14—C13	−1.2 (4)
C1—C2—C7—C6	−176.3 (3)	N1—C9—C14—C13	178.5 (2)
C4—C3—C8—O3	102.9 (3)	C12—C13—C14—C9	0.3 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O4^i	0.82	1.77	2.583 (2)	171
N1—H1A···O4	0.89	1.98	2.848 (3)	164
N1—H1B···O3^ii	0.89	1.85	2.713 (3)	163
N1—H1C···O3^i	0.89	1.90	2.774 (3)	165
C13—H13···O4^iii	0.93	2.54	3.328 (4)	143

Symmetry codes: (i) −x+1/2, y−1/2, −z+1/2; (ii) x, −y+2, z−1/2; (iii) x, y−1, z.