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ISSN: 2056-9890

3-Amino­benzoic acid–4-nitro­benzoic acid (1/1)

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: hkfun@usm.my

(Received 10 November 2008; accepted 10 November 2008; online 13 November 2008)

In the title 1:1 adduct, C7H5NO4·C7H7NO2, the nitro group of the 4-nitro benzoic acid is twisted from the attached ring by 4.40 (8)°. In the crystal, the mol­ecules are linked into ribbon-like structures along [150] and [1[\overline{5}]0] via O—H⋯O, N—H⋯O, N—H⋯N and C—H⋯O inter­molecular hydrogen bonds.

Related literature

For the applications of 3-amino­benzoic acid, see; Windholz (1976[Windholz, M. (1976). The Merck Index, 9th ed. Boca Raton, USA: Merck & Co. Inc.]). For related structures, see: Bowers et al. (2005[Bowers, J. R., Hopkins, G. W., Yap, G. P. A. & Wheeler, K. A. (2005). Cryst. Growth Des. 5, 727-736.]); Tonogaki et al. (1993[Tonogaki, M., Kawata, T., Ohba, S., Iwata, Y. & Shibuya, I. (1993). Acta Cryst. B49, 1031-1039.]); Voogd et al. (1980[Voogd, J., Verzijl, B. H. M. & Duisenberg, A. J. M. (1980). Acta Cryst. B36, 2805-2806.]).

[Scheme 1]

Experimental

Crystal data
  • C7H5NO4·C7H7NO2

  • Mr = 304.26

  • Monoclinic, C 2/c

  • a = 25.3707 (8) Å

  • b = 4.9875 (2) Å

  • c = 21.7276 (7) Å

  • β = 109.230 (2)°

  • V = 2595.93 (16) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 100.0 (1) K

  • 0.24 × 0.09 × 0.06 mm

Data collection
  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.971, Tmax = 0.993

  • 15472 measured reflections

  • 3759 independent reflections

  • 2197 reflections with I > 2σ(I)

  • Rint = 0.068

Refinement
  • R[F2 > 2σ(F2)] = 0.068

  • wR(F2) = 0.179

  • S = 1.01

  • 3759 reflections

  • 215 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.50 e Å−3

  • Δρmin = −0.36 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O4—H1O4⋯O5i 0.89 (4) 1.73 (4) 2.612 (2) 171 (3)
O6—H1O6⋯O3ii 0.91 (4) 1.75 (4) 2.652 (2) 171 (4)
N2—H1N1⋯O2iii 1.06 (4) 2.29 (4) 3.309 (3) 161 (3)
N2—H2N2⋯O2iv 0.90 (3) 2.60 (3) 3.351 (3) 142 (2)
C2—H2A⋯O5v 0.95 2.58 3.288 (3) 131
C4—H4A⋯O6iv 0.95 2.55 3.339 (3) 141
C10—H10A⋯O1iii 0.95 2.57 3.460 (3) 156
Symmetry codes: (i) [x+{\script{1\over 2}}, y-{\script{3\over 2}}, z]; (ii) [x-{\script{1\over 2}}, y+{\script{3\over 2}}, z]; (iii) x, y-1, z; (iv) [-x+{\script{3\over 2}}, -y+{\script{3\over 2}}, -z]; (v) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]).

Supporting information


Comment top

3-Aminobenzoic acid is used as an intermediate for dyes, pesticides and in other organic synthesis (Windholz, 1976). The crystal structures of 3-aminobenzoic acid (Voogd et al., 1980) and 4-aminobenzoic acid-4-nitrobenzoic acid have been reported (Bowers et al., 2005). As a part of our investigation of the interactions between acids, we report herein the crystal structure of the title compound.

The asymmetric unit (Fig. 1) contains one 3-aminobenzoic acid molecule and one 4-nitrobenzoic acid molecule. The bond lengths and angles of 3-aminobenzoic acid and 4-nitrobenzoic acid are found to have normal values (Voogd et al., 1980; Tonogaki et al., 1993). Both the molecules are almost planar with the maximum deviation from planarity being 0.026 (2) Å for atom O5 of 3-aminobenzoic acid molecule, and 0.078 (2) Å for atom O1 of nitrobenzoic acid molecule. In the 4-nitrobenzoic acid molecule, the nitro group is twisted slightly from the attached ring; the dihedral angle between C1—C6 and O1—O2/C3/N1 planes is 4.40 (8)°.

The crystal packing is consolidated by O—H···O, N—H···O, N—H···N and C—H···O intermolecular hydrogen bonds (Table 1). These hydrogen bonds link the molecules into ribbon like structures along [1 5 0] and [1 5 0] (Fig.2).

Related literature top

For the applications of 3-aminobenzoic acid, see; Windholz (1976). For related structures, see: Bowers et al. (2005); Tonogaki et al. (1993); Voogd et al. (1980).

Experimental top

3-Aminobenzoic acid and 4-nitrobenzoic acid were mixed in methanol (20 ml) in a 1:1 molar ratio. The clear colourless solution obtained was allowed to evaporate slowly. Colourless crystals were obtained after 2 d.

Refinement top

N and O-bound H atoms were located in a difference Fourier map and were allowed to refine freely. All the other H atoms were placed in calculated positions, with C—H = 0.95 Å, and refined using a riding model, with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2 (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the title compound. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. The crystal packing of the title compound, viewed along the c axis. Hydrogen bonds are shown as dashed lines.
3-Aminobenzoic acid–4-nitrobenzoic acid (1/1) top
Crystal data top
C7H5NO4·C7H7NO2F(000) = 1264
Mr = 304.26Dx = 1.557 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 2404 reflections
a = 25.3707 (8) Åθ = 3.0–29.9°
b = 4.9875 (2) ŵ = 0.12 mm1
c = 21.7276 (7) ÅT = 100 K
β = 109.230 (2)°Plate, yellow
V = 2595.93 (16) Å30.24 × 0.09 × 0.06 mm
Z = 8
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
3759 independent reflections
Radiation source: fine-focus sealed tube2197 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.068
ϕ and ω scansθmax = 30.0°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
h = 3435
Tmin = 0.971, Tmax = 0.993k = 77
15472 measured reflectionsl = 2930
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.068Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.179H atoms treated by a mixture of independent and constrained refinement
S = 1.01 w = 1/[σ2(Fo2) + (0.087P)2 + 1.6119P]
where P = (Fo2 + 2Fc2)/3
3759 reflections(Δ/σ)max = 0.001
215 parametersΔρmax = 0.50 e Å3
0 restraintsΔρmin = 0.36 e Å3
Crystal data top
C7H5NO4·C7H7NO2V = 2595.93 (16) Å3
Mr = 304.26Z = 8
Monoclinic, C2/cMo Kα radiation
a = 25.3707 (8) ŵ = 0.12 mm1
b = 4.9875 (2) ÅT = 100 K
c = 21.7276 (7) Å0.24 × 0.09 × 0.06 mm
β = 109.230 (2)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
3759 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
2197 reflections with I > 2σ(I)
Tmin = 0.971, Tmax = 0.993Rint = 0.068
15472 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0680 restraints
wR(F2) = 0.179H atoms treated by a mixture of independent and constrained refinement
S = 1.01Δρmax = 0.50 e Å3
3759 reflectionsΔρmin = 0.36 e Å3
215 parameters
Special details top

Experimental. The data was collected with the Oxford Cyrosystem Cobra low-temperature attachment.

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 (Å2) top
xyzUiso*/Ueq
O10.82025 (7)0.6966 (4)0.14306 (8)0.0238 (4)
O20.81699 (7)0.7604 (3)0.04310 (8)0.0236 (4)
O31.01559 (7)0.2306 (3)0.07932 (8)0.0175 (4)
O41.01017 (7)0.3174 (3)0.17847 (8)0.0183 (4)
O50.57710 (6)0.7825 (3)0.18023 (8)0.0180 (4)
O60.58739 (7)0.8769 (4)0.08408 (8)0.0194 (4)
N10.83479 (8)0.6430 (4)0.09588 (9)0.0178 (4)
N20.73488 (9)0.2432 (5)0.06366 (11)0.0217 (5)
C10.93325 (9)0.0854 (5)0.16778 (11)0.0166 (5)
H1A0.94610.01520.20700.020*
C20.89370 (9)0.2853 (5)0.16067 (11)0.0167 (5)
H2A0.87920.32410.19480.020*
C30.87598 (9)0.4267 (5)0.10277 (11)0.0158 (5)
C40.89605 (9)0.3786 (5)0.05146 (11)0.0160 (5)
H4A0.88310.48000.01230.019*
C50.93576 (9)0.1775 (5)0.05923 (11)0.0164 (5)
H5A0.95030.13950.02510.020*
C60.95413 (8)0.0322 (5)0.11703 (10)0.0136 (5)
C70.99642 (9)0.1847 (4)0.12311 (11)0.0145 (5)
C80.66801 (9)0.4869 (5)0.10050 (11)0.0172 (5)
H8A0.65840.59660.06270.021*
C90.70819 (9)0.2837 (5)0.10949 (11)0.0179 (5)
C100.72180 (10)0.1297 (5)0.16603 (12)0.0199 (5)
H10A0.74920.00690.17280.024*
C110.69646 (9)0.1707 (5)0.21230 (12)0.0203 (5)
H11A0.70660.06300.25050.024*
C120.65613 (9)0.3688 (5)0.20347 (11)0.0180 (5)
H12A0.63830.39620.23510.022*
C130.64223 (9)0.5267 (5)0.14746 (11)0.0152 (5)
C140.59973 (9)0.7398 (4)0.13881 (11)0.0143 (5)
H1O41.0354 (14)0.442 (8)0.1783 (15)0.056 (11)*
H1O60.5600 (15)0.998 (8)0.0809 (16)0.063 (11)*
H1N10.7575 (14)0.064 (8)0.0643 (16)0.063 (11)*
H2N20.7158 (12)0.302 (6)0.0233 (14)0.029 (8)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0264 (9)0.0247 (10)0.0238 (10)0.0060 (7)0.0131 (8)0.0027 (7)
O20.0266 (9)0.0214 (10)0.0227 (9)0.0058 (7)0.0079 (7)0.0042 (7)
O30.0198 (8)0.0161 (9)0.0190 (8)0.0049 (7)0.0095 (7)0.0019 (7)
O40.0226 (9)0.0164 (9)0.0182 (9)0.0086 (7)0.0098 (7)0.0039 (7)
O50.0213 (8)0.0155 (9)0.0190 (9)0.0037 (7)0.0090 (7)0.0012 (7)
O60.0222 (9)0.0206 (9)0.0185 (9)0.0069 (7)0.0108 (7)0.0035 (7)
N10.0180 (9)0.0171 (10)0.0187 (10)0.0008 (8)0.0067 (8)0.0014 (8)
N20.0229 (11)0.0244 (12)0.0197 (11)0.0051 (9)0.0096 (9)0.0015 (9)
C10.0168 (11)0.0159 (12)0.0173 (12)0.0005 (9)0.0060 (9)0.0008 (9)
C20.0180 (11)0.0171 (12)0.0173 (12)0.0008 (9)0.0091 (9)0.0019 (9)
C30.0123 (10)0.0125 (12)0.0227 (12)0.0023 (8)0.0057 (9)0.0028 (9)
C40.0180 (11)0.0138 (11)0.0173 (12)0.0020 (9)0.0073 (9)0.0034 (9)
C50.0181 (11)0.0164 (12)0.0168 (12)0.0000 (9)0.0087 (9)0.0002 (9)
C60.0121 (10)0.0125 (11)0.0164 (11)0.0018 (8)0.0051 (8)0.0007 (9)
C70.0139 (10)0.0132 (12)0.0169 (12)0.0018 (9)0.0058 (9)0.0010 (9)
C80.0174 (11)0.0155 (12)0.0195 (12)0.0017 (9)0.0073 (9)0.0011 (9)
C90.0151 (11)0.0173 (12)0.0222 (12)0.0025 (9)0.0075 (9)0.0058 (9)
C100.0172 (11)0.0151 (12)0.0251 (13)0.0029 (9)0.0040 (10)0.0019 (10)
C110.0193 (12)0.0179 (13)0.0224 (13)0.0012 (9)0.0052 (10)0.0006 (9)
C120.0184 (11)0.0163 (12)0.0197 (12)0.0025 (9)0.0069 (9)0.0000 (9)
C130.0126 (10)0.0138 (11)0.0201 (12)0.0010 (9)0.0066 (9)0.0014 (9)
C140.0140 (10)0.0137 (11)0.0155 (11)0.0000 (9)0.0053 (8)0.0014 (9)
Geometric parameters (Å, º) top
O1—N11.228 (2)C3—C41.391 (3)
O2—N11.233 (2)C4—C51.392 (3)
O3—C71.225 (3)C4—H4A0.95
O4—C71.315 (3)C5—C61.391 (3)
O4—H1O40.89 (4)C5—H5A0.95
O5—C141.235 (3)C6—C71.498 (3)
O6—C141.317 (3)C8—C131.396 (3)
O6—H1O60.91 (4)C8—C91.405 (3)
N1—C31.475 (3)C8—H8A0.95
N2—C91.391 (3)C9—C101.392 (3)
N2—H1N11.06 (4)C10—C111.375 (3)
N2—H2N20.90 (3)C10—H10A0.95
C1—C21.387 (3)C11—C121.390 (3)
C1—C61.397 (3)C11—H11A0.95
C1—H1A0.95C12—C131.394 (3)
C2—C31.382 (3)C12—H12A0.95
C2—H2A0.95C13—C141.481 (3)
C7—O4—H1O4109 (2)C1—C6—C7120.9 (2)
C14—O6—H1O6111 (2)O3—C7—O4124.3 (2)
O1—N1—O2123.7 (2)O3—C7—C6121.5 (2)
O1—N1—C3118.17 (19)O4—C7—C6114.23 (19)
O2—N1—C3118.17 (18)C13—C8—C9119.6 (2)
C9—N2—H1N1120.1 (18)C13—C8—H8A120.2
C9—N2—H2N2114.7 (18)C9—C8—H8A120.2
H1N1—N2—H2N2114 (3)N2—C9—C10120.9 (2)
C2—C1—C6119.8 (2)N2—C9—C8120.5 (2)
C2—C1—H1A120.1C10—C9—C8118.6 (2)
C6—C1—H1A120.1C11—C10—C9121.5 (2)
C3—C2—C1118.3 (2)C11—C10—H10A119.2
C3—C2—H2A120.8C9—C10—H10A119.2
C1—C2—H2A120.8C10—C11—C12120.3 (2)
C2—C3—C4123.1 (2)C10—C11—H11A119.8
C2—C3—N1118.23 (19)C12—C11—H11A119.8
C4—C3—N1118.6 (2)C11—C12—C13119.0 (2)
C3—C4—C5117.9 (2)C11—C12—H12A120.5
C3—C4—H4A121.0C13—C12—H12A120.5
C5—C4—H4A121.0C12—C13—C8120.9 (2)
C6—C5—C4119.9 (2)C12—C13—C14118.7 (2)
C6—C5—H5A120.0C8—C13—C14120.4 (2)
C4—C5—H5A120.0O5—C14—O6122.6 (2)
C5—C6—C1120.8 (2)O5—C14—C13121.7 (2)
C5—C6—C7118.24 (19)O6—C14—C13115.72 (19)
C6—C1—C2—C30.1 (3)C5—C6—C7—O4178.0 (2)
C1—C2—C3—C40.3 (3)C1—C6—C7—O41.3 (3)
C1—C2—C3—N1178.7 (2)C13—C8—C9—N2179.2 (2)
O1—N1—C3—C23.6 (3)C13—C8—C9—C101.0 (3)
O2—N1—C3—C2176.6 (2)N2—C9—C10—C11178.8 (2)
O1—N1—C3—C4175.0 (2)C8—C9—C10—C110.7 (3)
O2—N1—C3—C44.9 (3)C9—C10—C11—C120.1 (4)
C2—C3—C4—C50.2 (3)C10—C11—C12—C130.7 (3)
N1—C3—C4—C5178.7 (2)C11—C12—C13—C80.3 (3)
C3—C4—C5—C60.1 (3)C11—C12—C13—C14179.2 (2)
C4—C5—C6—C10.0 (3)C9—C8—C13—C120.5 (3)
C4—C5—C6—C7179.3 (2)C9—C8—C13—C14179.9 (2)
C2—C1—C6—C50.0 (3)C12—C13—C14—O51.0 (3)
C2—C1—C6—C7179.3 (2)C8—C13—C14—O5178.6 (2)
C5—C6—C7—O31.7 (3)C12—C13—C14—O6178.2 (2)
C1—C6—C7—O3179.0 (2)C8—C13—C14—O62.2 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O4—H1O4···O5i0.89 (4)1.73 (4)2.612 (2)171 (3)
O6—H1O6···O3ii0.91 (4)1.75 (4)2.652 (2)171 (4)
N2—H1N1···O2iii1.06 (4)2.29 (4)3.309 (3)161 (3)
N2—H2N2···O2iv0.90 (3)2.60 (3)3.351 (3)142 (2)
C2—H2A···O5v0.952.583.288 (3)131
C4—H4A···O6iv0.952.553.339 (3)141
C10—H10A···O1iii0.952.573.460 (3)156
Symmetry codes: (i) x+1/2, y3/2, z; (ii) x1/2, y+3/2, z; (iii) x, y1, z; (iv) x+3/2, y+3/2, z; (v) x+3/2, y1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC7H5NO4·C7H7NO2
Mr304.26
Crystal system, space groupMonoclinic, C2/c
Temperature (K)100
a, b, c (Å)25.3707 (8), 4.9875 (2), 21.7276 (7)
β (°) 109.230 (2)
V3)2595.93 (16)
Z8
Radiation typeMo Kα
µ (mm1)0.12
Crystal size (mm)0.24 × 0.09 × 0.06
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.971, 0.993
No. of measured, independent and
observed [I > 2σ(I)] reflections
15472, 3759, 2197
Rint0.068
(sin θ/λ)max1)0.704
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.068, 0.179, 1.01
No. of reflections3759
No. of parameters215
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.50, 0.36

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O4—H1O4···O5i0.89 (4)1.73 (4)2.612 (2)171 (3)
O6—H1O6···O3ii0.91 (4)1.75 (4)2.652 (2)171 (4)
N2—H1N1···O2iii1.06 (4)2.29 (4)3.309 (3)161 (3)
N2—H2N2···O2iv0.90 (3)2.60 (3)3.351 (3)142 (2)
C2—H2A···O5v0.952.583.288 (3)131
C4—H4A···O6iv0.952.553.339 (3)141
C10—H10A···O1iii0.952.573.460 (3)156
Symmetry codes: (i) x+1/2, y3/2, z; (ii) x1/2, y+3/2, z; (iii) x, y1, z; (iv) x+3/2, y+3/2, z; (v) x+3/2, y1/2, z+1/2.
 

Footnotes

Permanent address: Department of Physics, Karunya University, Karunya Nagar, Coimbatore 641114, India.

§Additional correspondence author, e-mail: robinsunj@yahoo.com.

Acknowledgements

HKF and SRJ thank the Malaysian Government and Universiti Sains Malaysia for the Science Fund grant No. 305/PFIZIK/613312. SRJ thanks Universiti Sains Malaysia for a post–doctoral research fellowship. CKQ thanks Universiti Sains Malaysia for a student assistanceship.

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