organic compounds
2-Methoxycarbonyl-6-nitrobenzoic acid
aSchool of Chemistry and Engineering, Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, Xuzhou Normal University, Xuzhou, Jiangsu 221116, People's Republic of China
*Correspondence e-mail: lzs@jsnu.edu.cn
In the title compound, C9H7NO6, the dihedral angles between the benzene ring and its three substituents are 29.99 (8)° for the nitro, 67.09 (8)° for the carboxy and 32.48 (10)° for the methoxycarbonyl group. In the crystal, one classical O—H⋯O and two nonclassical C—H⋯O contacts link adjacent molecules, forming a three-dimensional structure.
Related literature
For the bioactivity of the title compound, see: Xu & He (2010). For related structures, see: Glidewell et al. (2003); Wang et al. (2006).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: SMART (Bruker, 2001); cell SAINT (Bruker, 2001); data reduction: SAINT; 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.
Supporting information
https://doi.org/10.1107/S1600536812030462/sj5245sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812030462/sj5245Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S1600536812030462/sj5245Isup3.cml
A solution of 3-nitrophthalic acid (10.0 g) in acetic anhydride (15 ml) was refluxed for 1 h to obtain 3-nitrophthalic anhydride (8.0 g). Then the product was dissolved in 50 ml anhydrous methanol and stirred at room temperature for 2 h, after which 1 ml concentrated sulfuric acid was dropped into the mixture, refluxed for 24 h, cooled and filtered. The resulting solid was dimethyl 3-nitrophthalate. The filtrate was concentrated and then chromatographed over silica gel (mobile phase: n-hexane:acetone = 1:3). The title compound (I) was collected from mobile phase (1.0 g, m.p. 429–431 K). Crystals of (I) suitable for X-ray diffraction were obtained by slow evaporation of a toluene solution.
The H atom bonded to O4 was located in a difference Fourier map and refined freely. All other H atoms were placed in calculated positions, with C—H = 0.93–0.98 Å and included in the final cycles of
using a riding model, with Uiso(H) = 1.2Ueq(parent atom). In the absence of significant effects, Friedel pairs were averaged.2-(Methoxycarbonyl)-6-nitrobenzoic acid is an important precursor to farm chemicals (Xu & He, 2010). The X-ray structures of 3-nitrophthalic acid (Glidewell et al., 2003) and its organic adduct (Wang et al., 2006) have been determined previously, however, to our knowledge, no structure of the title compound (I) has been reported. In the molecule of (I), Fig. 1, none of three substituents are coplanar with the benzene ring. The dihedral angles between benzene ring and these substituents are 29.99 (8)° for nitro group (N1/O1/O2), 67.09 (8)° for carboxylic acid (C7/O3/O4), and 32.48 (10)° for methoxycarbonyl (C8/O5/O6/C9), substituent respectively. This variation is likely to result from attempts to minimise
between adjacent substituents. In the there are three hydrogen bonds, Table 1, one classical O4—H1···O5 and two nonclassical C9—H9B···O3 and C9—H9C···O2 contacts. These link adjacent molecules forming a three dimensional structure, Fig. 2.For the bioactivity of the title compound, see: Xu & He (2010). For related structures, see: Glidewell et al. (2003); Wang et al. (2006).
Data collection: SMART (Bruker, 2001); cell
SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); 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 (Sheldrick, 2008).Fig. 1. The structure of (I), showing 30% probability displacement ellipsoids and the atom-numbering scheme. | |
Fig. 2. The crystal packing for (I). |
C9H7NO6 | Dx = 1.541 Mg m−3 |
Mr = 225.16 | Melting point = 429–431 K |
Orthorhombic, P212121 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2ac 2ab | Cell parameters from 6294 reflections |
a = 7.647 (3) Å | θ = 2.6–27.1° |
b = 8.145 (3) Å | µ = 0.13 mm−1 |
c = 15.583 (6) Å | T = 296 K |
V = 970.6 (7) Å3 | Block, colourless |
Z = 4 | 0.27 × 0.22 × 0.16 mm |
F(000) = 464 |
Bruker SMART CCD area-detector diffractometer | 982 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.021 |
Graphite monochromator | θmax = 25.0°, θmin = 3.0° |
φ and ω scans | h = −9→9 |
6820 measured reflections | k = −8→9 |
1010 independent reflections | l = −18→18 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.027 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.077 | w = 1/[σ2(Fo2) + (0.0524P)2 + 0.1444P] where P = (Fo2 + 2Fc2)/3 |
S = 1.05 | (Δ/σ)max = 0.001 |
1010 reflections | Δρmax = 0.13 e Å−3 |
151 parameters | Δρmin = −0.13 e Å−3 |
1 restraint | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.058 (7) |
C9H7NO6 | V = 970.6 (7) Å3 |
Mr = 225.16 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 7.647 (3) Å | µ = 0.13 mm−1 |
b = 8.145 (3) Å | T = 296 K |
c = 15.583 (6) Å | 0.27 × 0.22 × 0.16 mm |
Bruker SMART CCD area-detector diffractometer | 982 reflections with I > 2σ(I) |
6820 measured reflections | Rint = 0.021 |
1010 independent reflections |
R[F2 > 2σ(F2)] = 0.027 | 1 restraint |
wR(F2) = 0.077 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | Δρmax = 0.13 e Å−3 |
1010 reflections | Δρmin = −0.13 e Å−3 |
151 parameters |
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 | ||
O6 | 1.15166 (19) | 0.64183 (18) | 0.90968 (8) | 0.0467 (4) | |
O5 | 1.0302 (2) | 0.41107 (19) | 0.95864 (9) | 0.0504 (4) | |
O4 | 0.6725 (2) | 0.22147 (17) | 0.89827 (8) | 0.0481 (4) | |
O3 | 0.6525 (2) | 0.4616 (2) | 0.96756 (9) | 0.0503 (4) | |
C5 | 0.7676 (2) | 0.4546 (2) | 0.82508 (10) | 0.0319 (4) | |
O2 | 0.4446 (3) | 0.3360 (3) | 0.67750 (11) | 0.0790 (6) | |
C2 | 0.9167 (3) | 0.5774 (3) | 0.67363 (12) | 0.0481 (5) | |
H2A | 0.9677 | 0.6167 | 0.6235 | 0.058* | |
O1 | 0.4073 (2) | 0.4102 (3) | 0.80807 (11) | 0.0694 (5) | |
C6 | 0.6778 (2) | 0.4551 (2) | 0.74720 (11) | 0.0359 (4) | |
N1 | 0.4967 (3) | 0.3961 (2) | 0.74398 (12) | 0.0466 (4) | |
C8 | 1.0429 (2) | 0.5175 (2) | 0.90536 (11) | 0.0343 (4) | |
C7 | 0.6900 (2) | 0.3825 (2) | 0.90552 (11) | 0.0353 (4) | |
C4 | 0.9356 (2) | 0.5210 (2) | 0.82510 (10) | 0.0342 (4) | |
C9 | 1.2706 (3) | 0.6459 (3) | 0.98203 (13) | 0.0532 (6) | |
H9A | 1.3540 | 0.7327 | 0.9741 | 0.064* | |
H9B | 1.3310 | 0.5429 | 0.9861 | 0.064* | |
H9C | 1.2057 | 0.6649 | 1.0338 | 0.064* | |
C3 | 1.0080 (3) | 0.5825 (3) | 0.74992 (13) | 0.0430 (5) | |
H3A | 1.1197 | 0.6277 | 0.7510 | 0.052* | |
C1 | 0.7503 (3) | 0.5143 (2) | 0.67198 (11) | 0.0436 (5) | |
H1A | 0.6872 | 0.5112 | 0.6210 | 0.052* | |
H1 | 0.630 (4) | 0.178 (3) | 0.9437 (12) | 0.078 (9)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O6 | 0.0477 (8) | 0.0497 (8) | 0.0428 (7) | −0.0100 (7) | −0.0081 (6) | 0.0050 (6) |
O5 | 0.0555 (8) | 0.0542 (8) | 0.0414 (7) | −0.0066 (7) | −0.0148 (7) | 0.0176 (7) |
O4 | 0.0640 (9) | 0.0431 (7) | 0.0372 (7) | −0.0043 (7) | 0.0154 (7) | 0.0068 (6) |
O3 | 0.0594 (9) | 0.0603 (9) | 0.0311 (7) | 0.0006 (8) | 0.0088 (6) | −0.0060 (6) |
C5 | 0.0369 (8) | 0.0321 (8) | 0.0267 (8) | 0.0043 (7) | 0.0019 (7) | 0.0008 (7) |
O2 | 0.0743 (11) | 0.1103 (15) | 0.0524 (9) | −0.0313 (12) | −0.0165 (9) | −0.0122 (10) |
C2 | 0.0598 (12) | 0.0531 (12) | 0.0314 (9) | −0.0055 (10) | 0.0045 (9) | 0.0121 (8) |
O1 | 0.0423 (8) | 0.1073 (15) | 0.0587 (9) | −0.0063 (10) | 0.0043 (8) | −0.0097 (10) |
C6 | 0.0399 (9) | 0.0363 (9) | 0.0315 (8) | 0.0017 (8) | −0.0011 (8) | 0.0015 (7) |
N1 | 0.0461 (8) | 0.0542 (10) | 0.0396 (8) | −0.0007 (8) | −0.0091 (7) | 0.0012 (8) |
C8 | 0.0350 (8) | 0.0374 (9) | 0.0304 (8) | 0.0036 (8) | 0.0021 (7) | 0.0026 (8) |
C7 | 0.0341 (8) | 0.0443 (10) | 0.0275 (8) | 0.0014 (8) | 0.0016 (8) | 0.0021 (8) |
C4 | 0.0397 (9) | 0.0339 (8) | 0.0290 (8) | 0.0022 (8) | −0.0002 (7) | 0.0042 (7) |
C9 | 0.0470 (11) | 0.0652 (13) | 0.0473 (10) | −0.0074 (11) | −0.0104 (9) | −0.0036 (10) |
C3 | 0.0447 (9) | 0.0479 (11) | 0.0364 (8) | −0.0054 (9) | 0.0029 (7) | 0.0111 (8) |
C1 | 0.0568 (11) | 0.0468 (10) | 0.0271 (8) | 0.0025 (9) | −0.0064 (8) | 0.0055 (8) |
O6—C8 | 1.312 (2) | C2—H2A | 0.9300 |
O6—C9 | 1.449 (2) | O1—N1 | 1.216 (3) |
O5—C8 | 1.204 (2) | C6—C1 | 1.383 (3) |
O4—C7 | 1.323 (3) | C6—N1 | 1.467 (3) |
O4—H1 | 0.856 (10) | C8—C4 | 1.496 (2) |
O3—C7 | 1.197 (2) | C4—C3 | 1.389 (3) |
C5—C4 | 1.394 (3) | C9—H9A | 0.9600 |
C5—C6 | 1.394 (2) | C9—H9B | 0.9600 |
C5—C7 | 1.506 (2) | C9—H9C | 0.9600 |
O2—N1 | 1.213 (2) | C3—H3A | 0.9300 |
C2—C1 | 1.373 (3) | C1—H1A | 0.9300 |
C2—C3 | 1.380 (3) | ||
C8—O6—C9 | 117.11 (15) | O3—C7—C5 | 123.81 (18) |
C7—O4—H1 | 112 (2) | O4—C7—C5 | 110.80 (15) |
C4—C5—C6 | 116.91 (16) | C3—C4—C5 | 120.48 (17) |
C4—C5—C7 | 120.96 (15) | C3—C4—C8 | 119.57 (17) |
C6—C5—C7 | 122.11 (16) | C5—C4—C8 | 119.86 (15) |
C1—C2—C3 | 119.78 (18) | O6—C9—H9A | 109.5 |
C1—C2—H2A | 120.1 | O6—C9—H9B | 109.5 |
C3—C2—H2A | 120.1 | H9A—C9—H9B | 109.5 |
C1—C6—C5 | 122.78 (18) | O6—C9—H9C | 109.5 |
C1—C6—N1 | 117.60 (17) | H9A—C9—H9C | 109.5 |
C5—C6—N1 | 119.58 (16) | H9B—C9—H9C | 109.5 |
O2—N1—O1 | 123.7 (2) | C2—C3—C4 | 120.93 (19) |
O2—N1—C6 | 118.15 (19) | C2—C3—H3A | 119.5 |
O1—N1—C6 | 118.16 (17) | C4—C3—H3A | 119.5 |
O5—C8—O6 | 124.84 (17) | C2—C1—C6 | 119.08 (18) |
O5—C8—C4 | 123.11 (17) | C2—C1—H1A | 120.5 |
O6—C8—C4 | 112.05 (14) | C6—C1—H1A | 120.5 |
O3—C7—O4 | 125.37 (18) | ||
C4—C5—C6—C1 | 1.6 (3) | C6—C5—C4—C3 | −0.7 (3) |
C7—C5—C6—C1 | −177.04 (16) | C7—C5—C4—C3 | 177.95 (18) |
C4—C5—C6—N1 | −176.33 (16) | C6—C5—C4—C8 | −177.14 (16) |
C7—C5—C6—N1 | 5.0 (3) | C7—C5—C4—C8 | 1.5 (2) |
C1—C6—N1—O2 | 30.9 (3) | O5—C8—C4—C3 | −145.9 (2) |
C5—C6—N1—O2 | −151.0 (2) | O6—C8—C4—C3 | 33.4 (2) |
C1—C6—N1—O1 | −149.0 (2) | O5—C8—C4—C5 | 30.5 (3) |
C5—C6—N1—O1 | 29.0 (3) | O6—C8—C4—C5 | −150.10 (16) |
C9—O6—C8—O5 | 3.2 (3) | C1—C2—C3—C4 | 1.5 (3) |
C9—O6—C8—C4 | −176.16 (16) | C5—C4—C3—C2 | −0.8 (3) |
C4—C5—C7—O3 | 67.3 (2) | C8—C4—C3—C2 | 175.65 (18) |
C6—C5—C7—O3 | −114.1 (2) | C3—C2—C1—C6 | −0.6 (3) |
C4—C5—C7—O4 | −111.59 (18) | C5—C6—C1—C2 | −0.9 (3) |
C6—C5—C7—O4 | 67.0 (2) | N1—C6—C1—C2 | 177.02 (18) |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1···O5i | 0.86 (1) | 1.85 (1) | 2.706 (2) | 178 (3) |
C9—H9C···O2ii | 0.96 | 2.52 | 3.465 (3) | 170 |
C9—H9B···O3iii | 0.96 | 2.56 | 3.291 (3) | 133 |
Symmetry codes: (i) x−1/2, −y+1/2, −z+2; (ii) −x+3/2, −y+1, z+1/2; (iii) x+1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C9H7NO6 |
Mr | 225.16 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 296 |
a, b, c (Å) | 7.647 (3), 8.145 (3), 15.583 (6) |
V (Å3) | 970.6 (7) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.13 |
Crystal size (mm) | 0.27 × 0.22 × 0.16 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6820, 1010, 982 |
Rint | 0.021 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.027, 0.077, 1.05 |
No. of reflections | 1010 |
No. of parameters | 151 |
No. of restraints | 1 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.13, −0.13 |
Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H1···O5i | 0.856 (10) | 1.851 (11) | 2.706 (2) | 178 (3) |
C9—H9C···O2ii | 0.96 | 2.52 | 3.465 (3) | 169.6 |
C9—H9B···O3iii | 0.96 | 2.56 | 3.291 (3) | 132.8 |
Symmetry codes: (i) x−1/2, −y+1/2, −z+2; (ii) −x+3/2, −y+1, z+1/2; (iii) x+1, y, z. |
Acknowledgements
The authors are grateful for Project Funding by the Priority Academic Program Development of Jiangsu Higher Education Institutions, the National Natural Science Foundation of China (grant No. 20802061) and the Natural Science Foundation of Jiangsu Education Department (grant No. 02KJB150007).
References
Bruker (2001). SAINT and SMART. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Glidewell, C., Low, J. N., Skakle, J. M. S. & Wardell, J. L. (2003). Acta Cryst. C59, o144–o146. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Wang, Y., Feng, W., Xue, L. & Zheng, J. (2006). Chin. J. Struct. Chem. 25, 923–926. CAS Google Scholar
Xu, H. & He, X. (2010). Bioorg. Med. Chem. Lett. 20, 4503–4506. Web of Science CrossRef CAS PubMed Google Scholar
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2-(Methoxycarbonyl)-6-nitrobenzoic acid is an important precursor to farm chemicals (Xu & He, 2010). The X-ray structures of 3-nitrophthalic acid (Glidewell et al., 2003) and its organic adduct (Wang et al., 2006) have been determined previously, however, to our knowledge, no structure of the title compound (I) has been reported. In the molecule of (I), Fig. 1, none of three substituents are coplanar with the benzene ring. The dihedral angles between benzene ring and these substituents are 29.99 (8)° for nitro group (N1/O1/O2), 67.09 (8)° for carboxylic acid (C7/O3/O4), and 32.48 (10)° for methoxycarbonyl (C8/O5/O6/C9), substituent respectively. This variation is likely to result from attempts to minimise steric hindrance between adjacent substituents. In the crystal structure, there are three hydrogen bonds, Table 1, one classical O4—H1···O5 and two nonclassical C9—H9B···O3 and C9—H9C···O2 contacts. These link adjacent molecules forming a three dimensional structure, Fig. 2.