3,5-Dicarboxyanilinium nitrate dihydrate

In the crystal of the title compound, C₈H₈NO₄⁺·NO₃⁻·2H₂O, the 5-ammonio­isophthalic acid cations, the nitrate anions and the water mol­ecules are linked by N—H...O, O—H...O and C—H ...O hydrogen bonds into a three-dimensional network. The structure is further stabilized by aromatic π–π stacking inter­actions, with centroid–centroid separations of 3.827 (2) Å.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.054
• wR factor = 0.129
• Data-to-parameter ratio = 14.5

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.10
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          3
PLAT042_ALERT_1_C Calc. and Reported MoietyFormula Strings  Differ          ?

Alert level G
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported   _diffrn_ambient_temperature        293 K

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   3 ALERT level G = General alerts; check

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

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S1. Comment

5-Aminobenzene-1,3-dioic acid (5-aminoisophthalic acid) is an important molecule due to its amphoteric property. The report on 5-aminobenzene-1,3-dioic acid hemihydrate (Dobson et al. 1998) is one of a series on hydrogen bonding in aminosubstituted carboxylic acids, and follows reports on a novel tetragonal phase of aminobutyric acid, on 8-aminocaprylic acid and on 3-aminoisobutyric acid monohydrate. In addition, 5-aminobenzene-1,3-dioic acid is an attractive ligand for use in the generation of polar coordination polymers (Liao et al., 2004).

The asymmetric unit of the title compound comprises two water molecules, a 5-ammonioisophthalic acid cation and one nitrate anion (Fig. 1). The crystal packing is stabilized by hydrogen bonds of N—H···O, O—H···O, C—H···O (Table 1) connecting neighbouring water molecules, cations and anions into a three-dimensional network (Fig. 2). The structure is further stabiized by aromatic π···π stacking interactions, with centroid-to-centroid separations of 3.827 (2) Å.

Related literature

For the crystal structure of 5-aminoisophthalic acid hemihydrate, see: Dobson et al. (1998). For the use of 5-aminoisophthalic acid as a ligand, see: Liao et al. (2004).

S2. Experimental

5-Aminoisophthalic acid (1.81 g, 10 mmol) was dissolved in water (5 ml), ethanol (20 ml) and nitric acid (0.57 g, 10 mmol) and the solution was filtered. After slowly evaporating over a period of 3 d, colourless prismatic crystals of the title compound suitable for X-ray diffraction analysis were isolated.

S3. Refinement

All the H atoms were calculated geometrically and were allowed to ride on their parent atomsd, with C—H = 0.93–0.97 Å, N—H = 0.89 Å, and with U_iso(H) = 1.2Ueq(C) and 1.5U_eq(N).

Computing details

Data collection: CrystalClear (Rigaku 2005); cell refinement: CrystalClear (Rigaku 2005); data reduction: CrystalClear (Rigaku 2005); 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: PRPKAPPA (Ferguson, 1999).

Figures

	Fig. 1. The asymmetric unit of the title compound, with displacement ellipsoids drawn at the 30% probability level. Intermolecular hydrogen bonds are shown as dashed lines.
	Fig. 2. Packing diagram of the title compound. Hydrogen bonds are shown as dashed lines.

3,5-Dicarboxyanilinium nitrate dihydrate

Crystal data

C8H8NO4^+·NO3^−·2H2O	F(000) = 584
Mr = 280.20	Dx = 1.547 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 1753 reflections
a = 8.3436 (17) Å	θ = 3.1–27.5°
b = 8.6234 (17) Å	µ = 0.14 mm^−1
c = 16.862 (3) Å	T = 293 K
β = 97.31 (3)°	Prism, colourless
V = 1203.4 (4) Å^3	0.35 × 0.25 × 0.10 mm
Z = 4

Data collection

Rigaku SCXmini diffractometer	2753 independent reflections
Radiation source: fine-focus sealed tube	1905 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.055
Detector resolution: 13.6612 pixels mm^-1	θmax = 27.5°, θmin = 3.2°
CCD profile fitting scans	h = −10→10
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	k = −11→11
Tmin = 0.960, Tmax = 0.986	l = −21→21
12169 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.054	w = 1/[σ^2(Fo^2) + (0.0423P)^2 + 0.7735P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.129	(Δ/σ)max < 0.001
S = 1.07	Δρmax = 0.28 e Å^−3
2753 reflections	Δρmin = −0.24 e Å^−3
190 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008)
0 restraints	Extinction coefficient: 0.0014 (1)
Primary atom site location: structure-invariant direct methods

Special details

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.

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

	x	y	z	Uiso*/Ueq
O4	0.4952 (2)	0.14675 (19)	0.42859 (10)	0.0442 (5)
H4	0.5275	0.0603	0.4432	0.066*
N1	0.3108 (2)	0.6452 (2)	0.29415 (11)	0.0328 (5)
H1A	0.3651	0.5813	0.2658	0.049*
H1B	0.3632	0.7350	0.3010	0.049*
H1C	0.2126	0.6614	0.2682	0.049*
C2	0.3575 (3)	0.4279 (2)	0.38793 (13)	0.0280 (5)
H2	0.4070	0.3744	0.3498	0.034*
O1	0.1136 (3)	0.6025 (2)	0.62566 (11)	0.0545 (6)
H1	0.0669	0.6559	0.6558	0.082*
O3	0.3885 (3)	0.1368 (2)	0.54276 (11)	0.0513 (5)
C4	0.2667 (3)	0.4405 (2)	0.51780 (13)	0.0296 (5)
H4A	0.2556	0.3946	0.5667	0.036*
C1	0.2969 (3)	0.5756 (2)	0.37216 (13)	0.0264 (5)
C5	0.2069 (3)	0.5891 (3)	0.50071 (14)	0.0299 (5)
C6	0.2225 (3)	0.6570 (2)	0.42699 (13)	0.0300 (5)
H6	0.1830	0.7563	0.4152	0.036*
O2	0.0772 (3)	0.8101 (2)	0.54705 (12)	0.0605 (6)
C3	0.3432 (3)	0.3610 (2)	0.46132 (13)	0.0275 (5)
C7	0.1260 (3)	0.6799 (3)	0.55994 (14)	0.0356 (6)
O5	0.2218 (2)	−0.0029 (2)	0.30373 (12)	0.0461 (5)
O6	0.4607 (2)	−0.06093 (19)	0.27628 (11)	0.0441 (5)
O7	0.3495 (2)	0.15470 (19)	0.23390 (12)	0.0460 (5)
N2	0.3433 (2)	0.0312 (2)	0.27105 (12)	0.0333 (5)
C8	0.4106 (3)	0.2034 (3)	0.47971 (13)	0.0304 (5)
O9	0.9920 (2)	0.7569 (2)	0.73715 (12)	0.0422 (5)
O8	0.8512 (3)	0.5594 (3)	0.84014 (16)	0.0667 (7)
H9A	0.916 (5)	0.828 (5)	0.729 (2)	0.091 (13)*
H8A	0.904 (4)	0.500 (5)	0.885 (2)	0.089 (13)*
H8B	0.781 (6)	0.612 (5)	0.861 (3)	0.111 (16)*
H9B	0.949 (6)	0.706 (6)	0.771 (3)	0.14 (2)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O4	0.0653 (12)	0.0295 (9)	0.0394 (10)	0.0196 (9)	0.0133 (9)	0.0042 (7)
N1	0.0348 (11)	0.0289 (10)	0.0359 (11)	0.0043 (8)	0.0092 (9)	0.0069 (8)
C2	0.0321 (12)	0.0225 (11)	0.0299 (12)	0.0021 (9)	0.0057 (10)	−0.0010 (9)
O1	0.0824 (15)	0.0496 (11)	0.0354 (10)	0.0243 (10)	0.0225 (10)	0.0014 (9)
O3	0.0760 (14)	0.0357 (10)	0.0470 (11)	0.0214 (10)	0.0261 (10)	0.0177 (8)
C4	0.0365 (13)	0.0251 (11)	0.0269 (12)	0.0028 (9)	0.0025 (10)	0.0010 (9)
C1	0.0283 (11)	0.0236 (11)	0.0275 (11)	−0.0002 (9)	0.0038 (9)	0.0026 (9)
C5	0.0323 (12)	0.0258 (11)	0.0313 (12)	0.0017 (9)	0.0029 (10)	−0.0025 (9)
C6	0.0345 (12)	0.0204 (10)	0.0348 (12)	0.0054 (9)	0.0027 (10)	0.0003 (9)
O2	0.0920 (16)	0.0371 (11)	0.0573 (13)	0.0270 (11)	0.0282 (12)	0.0011 (9)
C3	0.0317 (12)	0.0209 (10)	0.0293 (12)	0.0016 (9)	0.0021 (9)	0.0008 (9)
C7	0.0421 (14)	0.0308 (13)	0.0343 (13)	0.0059 (11)	0.0063 (11)	−0.0055 (10)
O5	0.0385 (10)	0.0427 (10)	0.0604 (12)	−0.0026 (8)	0.0199 (9)	0.0066 (9)
O6	0.0436 (10)	0.0346 (9)	0.0562 (12)	0.0130 (8)	0.0149 (9)	0.0030 (8)
O7	0.0483 (11)	0.0269 (9)	0.0643 (12)	−0.0019 (8)	0.0128 (9)	0.0126 (8)
N2	0.0363 (11)	0.0263 (10)	0.0377 (11)	−0.0009 (9)	0.0063 (9)	−0.0016 (8)
C8	0.0379 (13)	0.0246 (11)	0.0290 (12)	0.0042 (10)	0.0049 (10)	−0.0001 (9)
O9	0.0356 (10)	0.0465 (11)	0.0460 (11)	0.0073 (9)	0.0106 (9)	−0.0011 (9)
O8	0.0748 (16)	0.0582 (14)	0.0742 (17)	0.0179 (12)	0.0371 (14)	0.0138 (12)

Geometric parameters (Å, º)

O4—C8	1.279 (3)	C4—H4A	0.9300
O4—H4	0.8200	C1—C6	1.371 (3)
N1—C1	1.464 (3)	C5—C6	1.395 (3)
N1—H1A	0.8900	C5—C7	1.496 (3)
N1—H1B	0.8900	C6—H6	0.9300
N1—H1C	0.8900	O2—C7	1.205 (3)
C2—C1	1.383 (3)	C3—C8	1.488 (3)
C2—C3	1.384 (3)	O5—N2	1.249 (2)
C2—H2	0.9300	O6—N2	1.256 (2)
O1—C7	1.309 (3)	O7—N2	1.240 (2)
O1—H1	0.8200	O9—H9A	0.88 (4)
O3—C8	1.243 (3)	O9—H9B	0.84 (5)
C4—C5	1.392 (3)	O8—H8A	0.97 (4)
C4—C3	1.393 (3)	O8—H8B	0.85 (5)
C8—O4—H4	109.5	C6—C5—C7	118.5 (2)
C1—N1—H1A	109.5	C1—C6—C5	119.2 (2)
C1—N1—H1B	109.5	C1—C6—H6	120.4
H1A—N1—H1B	109.5	C5—C6—H6	120.4
C1—N1—H1C	109.5	C2—C3—C4	120.3 (2)
H1A—N1—H1C	109.5	C2—C3—C8	119.59 (19)
H1B—N1—H1C	109.5	C4—C3—C8	120.1 (2)
C1—C2—C3	119.0 (2)	O2—C7—O1	124.5 (2)
C1—C2—H2	120.5	O2—C7—C5	122.6 (2)
C3—C2—H2	120.5	O1—C7—C5	112.9 (2)
C7—O1—H1	109.5	O7—N2—O5	120.9 (2)
C5—C4—C3	119.7 (2)	O7—N2—O6	119.8 (2)
C5—C4—H4A	120.2	O5—N2—O6	119.32 (19)
C3—C4—H4A	120.2	O3—C8—O4	123.7 (2)
C6—C1—C2	121.8 (2)	O3—C8—C3	120.5 (2)
C6—C1—N1	119.39 (19)	O4—C8—C3	115.8 (2)
C2—C1—N1	118.78 (19)	H9A—O9—H9B	96 (4)
C4—C5—C6	119.9 (2)	H8A—O8—H8B	103 (4)
C4—C5—C7	121.6 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O6^i	0.93	2.58	3.324 (3)	138
O9—H9A···O7^ii	0.88 (4)	2.39 (4)	3.048 (3)	133 (3)
O9—H9A···O5^ii	0.88 (4)	1.94 (4)	2.801 (3)	168 (4)
O8—H8B···O3^iii	0.85 (5)	2.29 (5)	3.057 (3)	149 (4)
O8—H8A···O2^iv	0.97 (4)	2.00 (4)	2.882 (3)	151 (3)
O4—H4···O3^v	0.82	1.84	2.652 (2)	169
N1—H1C···O9^vi	0.89	1.98	2.839 (3)	163
N1—H1B···O6^vii	0.89	2.00	2.859 (3)	161
N1—H1B···O5^vii	0.89	2.55	3.134 (3)	124
O9—H9B···O8	0.84 (5)	1.96 (5)	2.796 (3)	171 (5)
N1—H1A···O7^i	0.89	2.46	2.933 (3)	114
N1—H1A···O6^i	0.89	2.09	2.963 (3)	165
O1—H1···O9^viii	0.82	1.80	2.611 (3)	169

Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x+1, −y+1, −z+1; (iii) −x+1, y+1/2, −z+3/2; (iv) −x+1, y−1/2, −z+3/2; (v) −x+1, −y, −z+1; (vi) x−1, −y+3/2, z−1/2; (vii) x, y+1, z; (viii) x−1, y, z.