Methyl 3-carboxy-5-nitrobenzoate.

The structure of the title compound, C(9)H(7)NO(6), is essentially planar [maximum deviation 0.284 (2)Å] except for the methyl H atoms. The crystal structure is stabilized by asymmetric O-H⋯O hydrogen bonds linking the hydrogen carboxyl-ates into pairs around the inversion centres. There is also π-π stacking of the benzene rings [centroid-centroid distance 3.6912 (12) Å].

Related literature

The title complex is as an important inter­mediate for the preparation of iodinated X-ray contrast media, see: Morin et al. (1987 ▶); Singh & Rathore (1980 ▶); Stacul (2001 ▶); Jin & Xiao (2005 ▶).

Experimental

Crystal data

C9H7NO6

M = 225.16

Monoclinic,

a = 7.3450 (15) Å

b = 8.9050 (18) Å

c = 14.474 (3) Å

β = 91.18 (3)°

V = 946.5 (3) Å3

Z = 4

Mo Kα radiation

μ = 0.14 mm−1

T = 293 (2) K

0.30 × 0.20 × 0.10 mm

Data collection

Enraf–Nonius CAD-4 diffractometer

Absorption correction: ψ scan (North et al., 1968 ▶) T min = 0.950, T max = 0.977

1859 measured reflections

1717 independent reflections

1284 reflections with I > 2σ(I)

R int = 0.021

3 standard reflections every 200 reflections intensity decay: 1.0%

Refinement

R[F 2 > 2σ(F 2)] = 0.039

wR(F 2) = 0.105

S = 1.03

1717 reflections

150 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.17 e Å−3

Δρmin = −0.13 e Å−3

Data collection: CAD-4 Software (Enraf–Nonius, 1989 ▶); cell refinement: CAD-4 Software; 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: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXL97.

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809001093/fb2119sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809001093/fb2119Isup2.hkl

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

C9H7NO6	F(000) = 464
Mr = 225.16	Dx = 1.580 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 25 reflections
a = 7.3450 (15) Å	θ = 10–13°
b = 8.9050 (18) Å	µ = 0.14 mm−1
c = 14.474 (3) Å	T = 293 K
β = 91.18 (3)°	Block, colourless
V = 946.5 (3) Å3	0.30 × 0.20 × 0.10 mm
Z = 4

Enraf–Nonius CAD-4 diffractometer	1284 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.021
graphite	θmax = 25.3°, θmin = 2.7°
ω/2θ scans	h = 0→8
Absorption correction: ψ scan (North et al., 1968)	k = 0→10
Tmin = 0.950, Tmax = 0.977	l = −17→17
1859 measured reflections	3 standard reflections every 200 reflections
1717 independent reflections	intensity decay: 1.0%

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)] = 0.039	Hydrogen site location: difference Fourier map
wR(F2) = 0.105	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ2(Fo2) + (0.057P)2 + 0.0354P] where P = (Fo2 + 2Fc2)/3
1717 reflections	(Δ/σ)max < 0.001
150 parameters	Δρmax = 0.17 e Å−3
0 restraints	Δρmin = −0.13 e Å−3
23 constraints

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
N	1.0387 (2)	0.49976 (17)	0.29780 (10)	0.0475 (4)
O1	1.30752 (17)	0.20120 (16)	0.64959 (9)	0.0588 (4)
C1	1.4451 (3)	0.2024 (3)	0.72271 (15)	0.0742 (7)
H1A	1.4327	0.1142	0.7602	0.111*
H1B	1.4301	0.2902	0.7603	0.111*
H1C	1.5638	0.2036	0.6962	0.111*
C2	1.3171 (2)	0.3110 (2)	0.58767 (12)	0.0442 (4)
O2	1.4321 (2)	0.40512 (19)	0.58894 (10)	0.0769 (5)
C3	1.1649 (2)	0.30531 (18)	0.51817 (11)	0.0375 (4)
O3	1.1685 (2)	0.58281 (18)	0.29145 (11)	0.0730 (5)
O4	0.9140 (2)	0.4969 (2)	0.24169 (11)	0.0832 (6)
C4	1.0120 (2)	0.21563 (18)	0.53024 (11)	0.0382 (4)
H4A	1.0053	0.1533	0.5816	0.046*
O5	0.70372 (17)	0.03897 (15)	0.54893 (9)	0.0561 (4)
C5	0.8694 (2)	0.21906 (18)	0.46585 (12)	0.0373 (4)
O6	0.57474 (18)	0.13777 (16)	0.42237 (9)	0.0560 (4)
H6B	0.475 (4)	0.072 (3)	0.4318 (19)	0.119 (10)*
C6	0.8793 (2)	0.31082 (18)	0.38850 (11)	0.0380 (4)
H6A	0.7850	0.3131	0.3447	0.046*
C7	1.0324 (2)	0.39840 (18)	0.37824 (11)	0.0368 (4)
C8	1.1757 (2)	0.39837 (18)	0.44108 (11)	0.0379 (4)
H8A	1.2771	0.4589	0.4323	0.046*
C9	0.7057 (2)	0.12519 (19)	0.48049 (12)	0.0396 (4)

	U11	U22	U33	U12	U13	U23
N	0.0515 (9)	0.0492 (9)	0.0419 (9)	−0.0049 (8)	−0.0003 (7)	0.0054 (7)
O1	0.0542 (8)	0.0634 (9)	0.0579 (8)	−0.0185 (7)	−0.0205 (6)	0.0167 (7)
C1	0.0644 (13)	0.1017 (19)	0.0555 (13)	−0.0228 (13)	−0.0249 (11)	0.0225 (13)
C2	0.0414 (9)	0.0467 (11)	0.0443 (10)	−0.0094 (9)	−0.0046 (8)	0.0030 (8)
O2	0.0626 (9)	0.0911 (12)	0.0759 (11)	−0.0421 (9)	−0.0269 (8)	0.0280 (9)
C3	0.0377 (9)	0.0344 (9)	0.0404 (9)	−0.0030 (7)	−0.0009 (7)	−0.0046 (7)
O3	0.0685 (10)	0.0765 (10)	0.0737 (10)	−0.0267 (8)	−0.0043 (8)	0.0321 (8)
O4	0.0783 (11)	0.1067 (14)	0.0635 (10)	−0.0288 (10)	−0.0274 (8)	0.0353 (9)
C4	0.0408 (9)	0.0331 (9)	0.0407 (9)	−0.0040 (7)	−0.0017 (7)	−0.0005 (7)
O5	0.0499 (8)	0.0578 (8)	0.0601 (8)	−0.0174 (6)	−0.0112 (6)	0.0174 (7)
C5	0.0369 (8)	0.0324 (9)	0.0424 (9)	−0.0027 (7)	−0.0020 (7)	−0.0053 (7)
O6	0.0454 (8)	0.0569 (9)	0.0650 (9)	−0.0201 (7)	−0.0184 (7)	0.0123 (7)
C6	0.0396 (9)	0.0369 (9)	0.0373 (9)	−0.0014 (8)	−0.0049 (7)	−0.0040 (7)
C7	0.0409 (9)	0.0355 (9)	0.0342 (8)	−0.0027 (7)	0.0020 (7)	−0.0005 (7)
C8	0.0332 (8)	0.0370 (9)	0.0436 (10)	−0.0037 (7)	0.0034 (7)	−0.0050 (8)
C9	0.0420 (9)	0.0330 (9)	0.0435 (10)	−0.0055 (8)	−0.0060 (8)	−0.0006 (8)

N—O3	1.211 (2)	C4—C5	1.388 (2)
N—O4	1.2122 (19)	C4—H4A	0.9300
N—C7	1.475 (2)	O5—C9	1.254 (2)
O1—C2	1.329 (2)	C5—C6	1.389 (2)
O1—C1	1.448 (2)	C5—C9	1.483 (2)
C1—H1A	0.9600	O6—C9	1.270 (2)
C1—H1B	0.9600	O6—H6B	0.95 (3)
C1—H1C	0.9600	C6—C7	1.379 (2)
C2—O2	1.190 (2)	C6—H6A	0.9300
C2—C3	1.489 (2)	C7—C8	1.377 (2)
C3—C4	1.393 (2)	C8—H8A	0.9300
C3—C8	1.393 (2)
O3—N—O4	123.18 (16)	C3—C4—H4A	119.9
O3—N—C7	118.11 (15)	C4—C5—C6	120.19 (15)
O4—N—C7	118.71 (15)	C4—C5—C9	119.62 (15)
C2—O1—C1	116.20 (15)	C6—C5—C9	120.19 (15)
O1—C1—H1A	109.5	C9—O6—H6B	115.3 (17)
O1—C1—H1B	109.5	C7—C6—C5	118.42 (15)
H1A—C1—H1B	109.5	C7—C6—H6A	120.8
O1—C1—H1C	109.5	C5—C6—H6A	120.8
H1A—C1—H1C	109.5	C8—C7—C6	122.86 (15)
H1B—C1—H1C	109.5	C8—C7—N	119.05 (15)
O2—C2—O1	123.71 (17)	C6—C7—N	118.05 (15)
O2—C2—C3	123.86 (17)	C7—C8—C3	118.28 (15)
O1—C2—C3	112.41 (15)	C7—C8—H8A	120.9
C4—C3—C8	120.06 (15)	C3—C8—H8A	120.9
C4—C3—C2	122.07 (15)	O5—C9—O6	123.82 (16)
C8—C3—C2	117.81 (15)	O5—C9—C5	118.73 (15)
C5—C4—C3	120.18 (16)	O6—C9—C5	117.45 (15)
C5—C4—H4A	119.9
C1—O1—C2—O2	1.4 (3)	C5—C6—C7—N	−177.71 (14)
C1—O1—C2—C3	−177.00 (17)	O3—N—C7—C8	−2.1 (2)
O2—C2—C3—C4	−165.32 (18)	O4—N—C7—C8	178.43 (17)
O1—C2—C3—C4	13.1 (2)	O3—N—C7—C6	175.95 (17)
O2—C2—C3—C8	12.0 (3)	O4—N—C7—C6	−3.6 (2)
O1—C2—C3—C8	−169.58 (15)	C6—C7—C8—C3	0.1 (2)
C8—C3—C4—C5	−0.3 (2)	N—C7—C8—C3	178.04 (14)
C2—C3—C4—C5	176.95 (16)	C4—C3—C8—C7	−0.1 (2)
C3—C4—C5—C6	0.7 (2)	C2—C3—C8—C7	−177.46 (15)
C3—C4—C5—C9	−178.81 (15)	C4—C5—C9—O5	−3.4 (2)
C4—C5—C6—C7	−0.6 (2)	C6—C5—C9—O5	177.14 (16)
C9—C5—C6—C7	178.84 (15)	C4—C5—C9—O6	176.41 (16)
C5—C6—C7—C8	0.2 (2)	C6—C5—C9—O6	−3.1 (2)

D—H···A	D—H	H···A	D···A	D—H···A
O6—H6B···O5i	0.95 (3)	1.67 (3)	2.6206 (19)	177.9 (17)
C8—H8A···O2ii	0.93	2.48	3.406 (2)	174

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O6—H6B⋯O5i	0.95 (3)	1.67 (3)	2.6206 (19)	177.9 (17)
C8—H8A⋯O2ii	0.93	2.48	3.406 (2)	174

Symmetry codes: (i) ; (ii) .