organic compounds
2-Amino-5-nitrophenyl 2-chlorophenyl ketone
aDepartment of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA, bDepartment of Chemistry, Howard University, 525 College Street NW, Washington DC 20059, USA, cDepartment of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India, and dRL Fine Chem, Bangalore 560 064, India
*Correspondence e-mail: rbutcher99@yahoo.com
In the title compound, C13H9ClN2O3, an intramolecular hydrogen bond between the carbonyl O and an amine H atom from the 2-aminobenzoyl group stabilizes the molecule, keeping these two groups nearly in the same plane [dihedral angle 14.6 (6)°]. The dihedral angle between the mean planes of the planar 2-aminobenzoyl and 2-chlorobenzoyl groups is 73.8 (6)°. The crystal packing is stabilized by a collection of intermediate hydrogen-bonding interactions which forms an infinite N—H⋯O⋯H—N—H⋯O hydrogen-bonded chain along the c axis in concert with weak N—H⋯Cl interactions in the same direction, producing a two-dimensional intermolecular bonding network parallel to (001). Additional weak C—Cl⋯Cg [Cl⋯Cg = 3.858 (3) Å] and N—O⋯Cg [O⋯Cg = 3.574 (1) and 3.868 (6) Å] π-ring interactions provide added support to the crystal stability. A MOPAC computational calculation gives support to these observations.
Related literature
For related structures, see: Cox et al. (1997, 2008); Harrison et al. (2005); Malathy Sony et al. (2005); Prasanna & Guru Row (2000); Xing et al. (2005). For background to benzophenone derivatives, see: Colpaert et al. (2004); Deleu et al. (1992); Duncan et al. (2004); Evans et al. (1987); Ottosen et al. (2003); Revesz et al. (2004); Sieroń et al. (2004); Wiesner et al. (2002). For a description of the Cambridge Structural Database, see: Allen (2002). For MOPAC AM1 computational calculations, see: Schmidt & Polik (2007).
Experimental
Crystal data
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Refinement
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Data collection: CrysAlisPro (Oxford Diffraction, 2007); cell CrysAlisPro; data reduction: CrysAlisPro; 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
10.1107/S160053680902755X/kj2123sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S160053680902755X/kj2123Isup2.hkl
The title compound was obtained as a gift sample from R. L. Fine Chem, Bangalore, India. The compound was used without further purification. Pale yellow crystals (m.p. 378–380 K) were obtained by slow evaporation from acetonitrile solution.
All of the H atoms were placed in their calculated positions and then refined using the riding model with N—H = 0.88, C—H = 0.95 Å, and with Uiso(H) = 1.18–1.21Ueq(C,N).
Data collection: CrysAlis PRO (Oxford Diffraction, 2007); cell
CrysAlis PRO (Oxford Diffraction, 2007); data reduction: CrysAlis PRO (Oxford Diffraction, 2007); 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).C13H9ClN2O3 | F(000) = 568 |
Mr = 276.67 | Dx = 1.485 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 4505 reflections |
a = 10.6120 (3) Å | θ = 4.7–32.6° |
b = 11.3314 (3) Å | µ = 0.31 mm−1 |
c = 10.8456 (3) Å | T = 110 K |
β = 108.399 (3)° | Chunk, colorless |
V = 1237.50 (6) Å3 | 0.47 × 0.36 × 0.28 mm |
Z = 4 |
Oxford Diffraction Gemini R CCD diffractometer | 4131 independent reflections |
Radiation source: fine-focus sealed tube | 3069 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.021 |
Detector resolution: 10.5081 pixels mm-1 | θmax = 32.7°, θmin = 4.7° |
ϕ and ω scans | h = −15→16 |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007) | k = −13→16 |
Tmin = 0.868, Tmax = 0.916 | l = −16→11 |
8758 measured reflections |
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)] = 0.036 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.099 | H-atom parameters constrained |
S = 1.04 | w = 1/[σ2(Fo2) + (0.0548P)2] where P = (Fo2 + 2Fc2)/3 |
4131 reflections | (Δ/σ)max < 0.001 |
172 parameters | Δρmax = 0.42 e Å−3 |
0 restraints | Δρmin = −0.27 e Å−3 |
C13H9ClN2O3 | V = 1237.50 (6) Å3 |
Mr = 276.67 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 10.6120 (3) Å | µ = 0.31 mm−1 |
b = 11.3314 (3) Å | T = 110 K |
c = 10.8456 (3) Å | 0.47 × 0.36 × 0.28 mm |
β = 108.399 (3)° |
Oxford Diffraction Gemini R CCD diffractometer | 4131 independent reflections |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007) | 3069 reflections with I > 2σ(I) |
Tmin = 0.868, Tmax = 0.916 | Rint = 0.021 |
8758 measured reflections |
R[F2 > 2σ(F2)] = 0.036 | 0 restraints |
wR(F2) = 0.099 | H-atom parameters constrained |
S = 1.04 | Δρmax = 0.42 e Å−3 |
4131 reflections | Δρmin = −0.27 e Å−3 |
172 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 | ||
Cl | 0.96431 (3) | 0.63182 (3) | 0.78827 (3) | 0.02769 (10) | |
O1 | 0.48712 (10) | 0.77733 (9) | 0.32532 (9) | 0.0350 (2) | |
O2 | 0.50201 (9) | 0.76958 (8) | 0.52898 (8) | 0.0271 (2) | |
O3 | 0.82129 (9) | 0.31290 (8) | 0.73196 (7) | 0.02303 (19) | |
N1 | 0.82197 (10) | 0.31577 (9) | 0.48161 (9) | 0.0214 (2) | |
H1A | 0.8367 | 0.2872 | 0.4120 | 0.026* | |
H1B | 0.8515 | 0.2779 | 0.5561 | 0.026* | |
N2 | 0.52756 (10) | 0.73094 (9) | 0.43331 (9) | 0.0211 (2) | |
C1 | 0.75466 (11) | 0.41681 (10) | 0.47433 (10) | 0.0162 (2) | |
C2 | 0.70760 (12) | 0.47688 (11) | 0.35352 (10) | 0.0197 (2) | |
H2A | 0.7267 | 0.4453 | 0.2802 | 0.024* | |
C3 | 0.63591 (12) | 0.57843 (11) | 0.33976 (10) | 0.0202 (2) | |
H3A | 0.6049 | 0.6169 | 0.2579 | 0.024* | |
C4 | 0.60840 (11) | 0.62550 (10) | 0.44837 (10) | 0.0169 (2) | |
C5 | 0.65568 (10) | 0.57301 (10) | 0.56856 (10) | 0.0157 (2) | |
H5A | 0.6376 | 0.6076 | 0.6410 | 0.019* | |
C6 | 0.73013 (10) | 0.46916 (10) | 0.58484 (10) | 0.0148 (2) | |
C7 | 0.77971 (11) | 0.41506 (10) | 0.71401 (10) | 0.0159 (2) | |
C8 | 0.77845 (11) | 0.48654 (10) | 0.83067 (9) | 0.0154 (2) | |
C9 | 0.85984 (11) | 0.58380 (11) | 0.87385 (10) | 0.0184 (2) | |
C10 | 0.86275 (12) | 0.64296 (11) | 0.98728 (11) | 0.0228 (3) | |
H10A | 0.9199 | 0.7088 | 1.0165 | 0.027* | |
C11 | 0.78122 (12) | 0.60456 (12) | 1.05687 (11) | 0.0240 (3) | |
H11A | 0.7827 | 0.6443 | 1.1345 | 0.029* | |
C12 | 0.69750 (12) | 0.50870 (12) | 1.01432 (10) | 0.0214 (2) | |
H12A | 0.6406 | 0.4839 | 1.0616 | 0.026* | |
C13 | 0.69720 (11) | 0.44907 (10) | 0.90242 (10) | 0.0174 (2) | |
H13A | 0.6413 | 0.3823 | 0.8744 | 0.021* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl | 0.02888 (16) | 0.03213 (19) | 0.02478 (15) | −0.01301 (13) | 0.01233 (12) | −0.00264 (12) |
O1 | 0.0449 (6) | 0.0315 (6) | 0.0230 (4) | 0.0161 (5) | 0.0026 (4) | 0.0071 (4) |
O2 | 0.0329 (5) | 0.0238 (5) | 0.0292 (4) | 0.0088 (4) | 0.0161 (4) | 0.0015 (4) |
O3 | 0.0372 (5) | 0.0166 (4) | 0.0187 (4) | 0.0056 (4) | 0.0137 (3) | 0.0035 (3) |
N1 | 0.0332 (5) | 0.0174 (5) | 0.0147 (4) | 0.0061 (4) | 0.0092 (4) | −0.0015 (4) |
N2 | 0.0217 (5) | 0.0192 (5) | 0.0209 (5) | 0.0027 (4) | 0.0045 (4) | 0.0014 (4) |
C1 | 0.0192 (5) | 0.0147 (5) | 0.0147 (5) | −0.0015 (4) | 0.0054 (4) | −0.0022 (4) |
C2 | 0.0259 (6) | 0.0212 (6) | 0.0125 (4) | 0.0014 (5) | 0.0066 (4) | −0.0012 (4) |
C3 | 0.0242 (5) | 0.0220 (6) | 0.0129 (5) | 0.0015 (5) | 0.0035 (4) | 0.0013 (4) |
C4 | 0.0180 (5) | 0.0151 (6) | 0.0172 (5) | 0.0010 (4) | 0.0047 (4) | −0.0006 (4) |
C5 | 0.0179 (5) | 0.0151 (6) | 0.0149 (5) | −0.0023 (4) | 0.0063 (4) | −0.0030 (4) |
C6 | 0.0182 (5) | 0.0139 (5) | 0.0125 (4) | −0.0011 (4) | 0.0052 (4) | −0.0006 (4) |
C7 | 0.0194 (5) | 0.0150 (5) | 0.0148 (5) | −0.0009 (4) | 0.0076 (4) | 0.0005 (4) |
C8 | 0.0201 (5) | 0.0147 (5) | 0.0115 (4) | 0.0026 (4) | 0.0051 (4) | 0.0019 (4) |
C9 | 0.0200 (5) | 0.0193 (6) | 0.0165 (5) | −0.0007 (4) | 0.0066 (4) | 0.0009 (4) |
C10 | 0.0257 (6) | 0.0220 (6) | 0.0191 (5) | −0.0029 (5) | 0.0047 (4) | −0.0050 (5) |
C11 | 0.0290 (6) | 0.0271 (7) | 0.0155 (5) | 0.0027 (5) | 0.0067 (4) | −0.0047 (5) |
C12 | 0.0247 (6) | 0.0267 (7) | 0.0149 (5) | 0.0023 (5) | 0.0091 (4) | 0.0018 (4) |
C13 | 0.0211 (5) | 0.0163 (6) | 0.0150 (5) | −0.0004 (4) | 0.0060 (4) | 0.0016 (4) |
Cl—C9 | 1.7426 (12) | C5—C6 | 1.3972 (15) |
O1—N2 | 1.2309 (13) | C5—H5A | 0.9500 |
O2—N2 | 1.2326 (13) | C6—C7 | 1.4663 (15) |
O3—C7 | 1.2322 (14) | C7—C8 | 1.5059 (15) |
N1—C1 | 1.3385 (15) | C8—C9 | 1.3873 (16) |
N1—H1A | 0.8800 | C8—C13 | 1.3975 (15) |
N1—H1B | 0.8800 | C9—C10 | 1.3927 (16) |
N2—C4 | 1.4498 (15) | C10—C11 | 1.3856 (18) |
C1—C2 | 1.4201 (15) | C10—H10A | 0.9500 |
C1—C6 | 1.4329 (14) | C11—C12 | 1.3868 (18) |
C2—C3 | 1.3614 (17) | C11—H11A | 0.9500 |
C2—H2A | 0.9500 | C12—C13 | 1.3882 (15) |
C3—C4 | 1.4052 (15) | C12—H12A | 0.9500 |
C3—H3A | 0.9500 | C13—H13A | 0.9500 |
C4—C5 | 1.3754 (15) | ||
C1—N1—H1A | 120.0 | C1—C6—C7 | 121.40 (10) |
C1—N1—H1B | 120.0 | O3—C7—C6 | 123.11 (10) |
H1A—N1—H1B | 120.0 | O3—C7—C8 | 118.06 (9) |
O1—N2—O2 | 123.10 (11) | C6—C7—C8 | 118.83 (10) |
O1—N2—C4 | 118.38 (10) | C9—C8—C13 | 118.76 (10) |
O2—N2—C4 | 118.52 (9) | C9—C8—C7 | 122.77 (9) |
N1—C1—C2 | 119.35 (10) | C13—C8—C7 | 118.36 (10) |
N1—C1—C6 | 122.63 (10) | C8—C9—C10 | 121.23 (10) |
C2—C1—C6 | 118.00 (10) | C8—C9—Cl | 120.08 (8) |
C3—C2—C1 | 121.87 (10) | C10—C9—Cl | 118.67 (9) |
C3—C2—H2A | 119.1 | C11—C10—C9 | 119.10 (11) |
C1—C2—H2A | 119.1 | C11—C10—H10A | 120.5 |
C2—C3—C4 | 119.06 (10) | C9—C10—H10A | 120.5 |
C2—C3—H3A | 120.5 | C10—C11—C12 | 120.62 (11) |
C4—C3—H3A | 120.5 | C10—C11—H11A | 119.7 |
C5—C4—C3 | 121.35 (11) | C12—C11—H11A | 119.7 |
C5—C4—N2 | 119.28 (10) | C11—C12—C13 | 119.78 (11) |
C3—C4—N2 | 119.37 (10) | C11—C12—H12A | 120.1 |
C4—C5—C6 | 120.43 (10) | C13—C12—H12A | 120.1 |
C4—C5—H5A | 119.8 | C12—C13—C8 | 120.49 (11) |
C6—C5—H5A | 119.8 | C12—C13—H13A | 119.8 |
C5—C6—C1 | 119.20 (9) | C8—C13—H13A | 119.8 |
C5—C6—C7 | 119.40 (9) | ||
N1—C1—C2—C3 | 178.41 (11) | C1—C6—C7—O3 | −14.58 (17) |
C6—C1—C2—C3 | −2.95 (17) | C5—C6—C7—C8 | −14.71 (16) |
C1—C2—C3—C4 | 0.38 (18) | C1—C6—C7—C8 | 166.26 (10) |
C2—C3—C4—C5 | 1.95 (18) | O3—C7—C8—C9 | 112.56 (13) |
C2—C3—C4—N2 | −177.50 (11) | C6—C7—C8—C9 | −68.24 (14) |
O1—N2—C4—C5 | 179.35 (11) | O3—C7—C8—C13 | −63.73 (14) |
O2—N2—C4—C5 | −1.01 (16) | C6—C7—C8—C13 | 115.48 (12) |
O1—N2—C4—C3 | −1.19 (17) | C13—C8—C9—C10 | 0.79 (17) |
O2—N2—C4—C3 | 178.46 (11) | C7—C8—C9—C10 | −175.49 (11) |
C3—C4—C5—C6 | −1.56 (17) | C13—C8—C9—Cl | 179.06 (8) |
N2—C4—C5—C6 | 177.89 (10) | C7—C8—C9—Cl | 2.79 (15) |
C4—C5—C6—C1 | −1.10 (16) | C8—C9—C10—C11 | −0.93 (18) |
C4—C5—C6—C7 | 179.85 (10) | Cl—C9—C10—C11 | −179.23 (10) |
N1—C1—C6—C5 | −178.14 (11) | C9—C10—C11—C12 | −0.14 (19) |
C2—C1—C6—C5 | 3.28 (16) | C10—C11—C12—C13 | 1.31 (19) |
N1—C1—C6—C7 | 0.89 (17) | C11—C12—C13—C8 | −1.45 (18) |
C2—C1—C6—C7 | −177.69 (10) | C9—C8—C13—C12 | 0.41 (17) |
C5—C6—C7—O3 | 164.45 (11) | C7—C8—C13—C12 | 176.85 (10) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O3i | 0.88 | 2.22 | 3.0733 (12) | 164 |
N1—H1B···O3 | 0.88 | 2.07 | 2.7176 (12) | 130 |
N1—H1B···Clii | 0.88 | 2.71 | 3.4848 (10) | 148 |
C13—H13A···O2iii | 0.95 | 2.46 | 3.1862 (14) | 133 |
Symmetry codes: (i) x, −y+1/2, z−1/2; (ii) −x+2, y−1/2, −z+3/2; (iii) −x+1, y−1/2, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | C13H9ClN2O3 |
Mr | 276.67 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 110 |
a, b, c (Å) | 10.6120 (3), 11.3314 (3), 10.8456 (3) |
β (°) | 108.399 (3) |
V (Å3) | 1237.50 (6) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.31 |
Crystal size (mm) | 0.47 × 0.36 × 0.28 |
Data collection | |
Diffractometer | Oxford Diffraction Gemini R CCD diffractometer |
Absorption correction | Multi-scan (CrysAlis RED; Oxford Diffraction, 2007) |
Tmin, Tmax | 0.868, 0.916 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8758, 4131, 3069 |
Rint | 0.021 |
(sin θ/λ)max (Å−1) | 0.760 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.036, 0.099, 1.04 |
No. of reflections | 4131 |
No. of parameters | 172 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.42, −0.27 |
Computer programs: CrysAlis PRO (Oxford Diffraction, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O3i | 0.88 | 2.22 | 3.0733 (12) | 163.7 |
N1—H1B···O3 | 0.88 | 2.07 | 2.7176 (12) | 129.7 |
N1—H1B···Clii | 0.88 | 2.71 | 3.4848 (10) | 148.0 |
C13—H13A···O2iii | 0.95 | 2.46 | 3.1862 (14) | 133.2 |
Symmetry codes: (i) x, −y+1/2, z−1/2; (ii) −x+2, y−1/2, −z+3/2; (iii) −x+1, y−1/2, −z+3/2. |
Acknowledgements
QNMHA thanks the University of Mysore for the use of its research facilities. RJB acknowledges the NSF MRI program (grant No. CHE-0619278) for funds to purchase an X-ray diffractometer.
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Benzophenone derivatives are widely used in sunscreen lotions for UVA protection (Deleu et al., 1992). Benzophenone and related analogues have been reported to act as antiallergic, anti-inflammatory, antiasthamatic, antimalarial, anti-microbial and antianaphylactic agents (Evans et al., 1987; Wiesner et al., 2002; Sieroń et al., 2004). The competence of benzophenones as chemotherapeutic agents, especially as inhibitors of HIV-1 reverse transcriptase RT, cancer and inflammation, is well established and their chemistry has been studied extensively (Revesz et al., 2004). Phenylmethanones are a class of compounds having many pharmacological properties. 4-Aminobenzophenones have high anti-inflammatory activity (Ottosen et al., 2003), a benzophenyl cyano derivative acts as a vasorelaxant (Duncan et al., 2004) and the piperidinyl derivative produces analgesia (Colpaert et al., 2004). The crystal structures of some related compounds, viz., N-(2-benzoyl-4-chlorophenyl)-2-chloroacetamide (Malathy Sony et al., 2005), 2-chloroacetamido-5-chlorobenzophenone and 2-chloroacetamido-5-chloro-2'-fluorobenzophenone (Prasanna & Guru Row, 2000), 2-methylamino-5-chlorobenzophenone (Cox et al., 1997), 2-amino-2'-chloro-5-methylbenzophenone (Xing et al., 2005) and 3-chloro-4-hydroxy-4'-methylbenzophenone (Harrison et al., 2005) have been reported. Over 450 crystal structures of benzophenone derivatives in the Cambridge Structural Database (CSD, Version 5.26; Allen, 2002) highlight the importance of structural studies on such pharmaceutically useful compounds. The title compound, C13H9ClN2O3, is an intermediate in the synthesis of certain anxiolytic, anticonvulsant and sedative drugs. The title compound is also a starting material for the synthesis of diazepam and other benzodiazepines. In view of the importance of the title compound, the present paper describes its crystal structure.
The title compound, C13H9ClN2O3, crystallizes with one molecule in the asymmetric unit with Z = 4. An intramolecular hydrogen bond between the carbonyl oxygen (O3) and an amine hydrogen atom (H1B) from the 2-amino-5-nitrobenzoyl group keeps these two groups nearly in the same plane releative to each other (Fig. 1). The dihedral angle between the mean planes of the carbony group (-C6-C7(O3)-C8-) and the mean planes of the 2-amino and 2'-chlorobenzoyl planar groups is 14.6 (6)° and 66.2 (9)°, respectively. The C5-C6-C7-O3 torsion angle (164.45 (11)°) supports this observation. The nitro group is twisted slightly away from the plane of the 2-amino-benzyl group (O2-N2-C4-C3 torsion angle = 178.46 (11)°). The dihedral angle between the mean planes of the 2-aminobenzyl and 2'-chlorobenzyl planar groups is 73.8 (6)°. This value lies between the large twist angle of 83.72 (6)° as seen in 2-amino and 2'-chlorobenzenophenone, C13H9Cl2NO, (Cox et al., 2008) and 64.66 (8)° observed in 4-chloro-4'-hydroxybenzophenone, C13H9ClO2 (Cox et al., 2008). Crystal packing is supported by a collection of intermediate N1-H1A···O3, N1-H1B···O3, C13-H13A···O2 hydrogen bonds and weak N1-H1B···Cl intermolecular interactions (see Table 1) which produces an infinite, two-dimensional N-H···O···H-N-H···O bonding network parallel to the (001) plane of the unit cell (Fig. 2). Additional weak C9-Cl···Cg(2) [Cl···Cg(2)= 3.858 (3)Å], N2-O1···Cg(2) [O1···Cg(2) = 3.574 (1)Å] and N2-O2···Cg(1) [O2···Cg(1) = 3.868 (6)Å] π-ring interactions (-x, 1-y, -x; x, 1/2-y, 1/2+z; 1-x, 1-y, 1-z; Cg(1) = C1-C6 and Cg(2) = C8-C13 centroids, respectively) collectively provide added support to crystal stability.
After a MOPAC AM1 computational calculation (Schmidt & Polik, 2007), the nitro group now lies in the plane of the 2-aminobenzoyl group. The dihedral angle between the mean planes of the 2-aminobenzoyl and 2'-chlorobenzoyl planar groups becomes 88.6 (1)° while the dihedral angle between the mean planes of the carbony group (-C6-C7(O3)-C8-) and the mean planes of the 2-amino and 2'-chlorobenzoyl planar groups becomes 19.7 (3)° and 81.7 (1)°, respectively. This supports the observation of a collective action of intermediate N-H···O, C-H···O hydrogen bonds, weak N-H···Cl intermolecular interactions and weak C-Cl···Cg, N-O···Cg π-ring interactions influencing crystal packing stability.