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Acta Crystallogr Sect E Struct Rep Online. 2009 August 1; 65(Pt 8): o1908–o1909.
Published online 2009 July 18. doi:  10.1107/S160053680902755X
PMCID: PMC2977436

2-Amino-5-nitro­phenyl 2-chloro­phenyl ketone

Abstract

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 [triangle], 2008 [triangle]); Harrison et al. (2005 [triangle]); Malathy Sony et al. (2005 [triangle]); Prasanna & Guru Row (2000 [triangle]); Xing et al. (2005 [triangle]). For background to benzophenone derivatives, see: Colpaert et al. (2004 [triangle]); Deleu et al. (1992 [triangle]); Duncan et al. (2004 [triangle]); Evans et al. (1987 [triangle]); Ottosen et al. (2003 [triangle]); Revesz et al. (2004 [triangle]); Sieroń et al. (2004 [triangle]); Wiesner et al. (2002 [triangle]). For a description of the Cambridge Structural Database, see: Allen (2002 [triangle]). For MOPAC AM1 computational calculations, see: Schmidt & Polik (2007 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-o1908-scheme1.jpg

Experimental

Crystal data

  • C13H9ClN2O3
  • M r = 276.67
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1908-efi1.jpg
  • a = 10.6120 (3) Å
  • b = 11.3314 (3) Å
  • c = 10.8456 (3) Å
  • β = 108.399 (3)°
  • V = 1237.50 (6) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.31 mm−1
  • T = 110 K
  • 0.47 × 0.36 × 0.28 mm

Data collection

  • Oxford Diffraction Gemini R CCD diffractometer
  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007 [triangle]) T min = 0.868, T max = 0.916
  • 8758 measured reflections
  • 4131 independent reflections
  • 3069 reflections with I > 2σ(I)
  • R int = 0.021

Refinement

  • R[F 2 > 2σ(F 2)] = 0.036
  • wR(F 2) = 0.099
  • S = 1.04
  • 4131 reflections
  • 172 parameters
  • H-atom parameters constrained
  • Δρmax = 0.42 e Å−3
  • Δρmin = −0.27 e Å−3

Data collection: CrysAlisPro (Oxford Diffraction, 2007 [triangle]); cell refinement: CrysAlisPro; data reduction: CrysAlisPro; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXTL.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053680902755X/kj2123sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053680902755X/kj2123Isup2.hkl

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

Acknowledgments

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.

supplementary crystallographic information

Comment

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.

Experimental

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.

Refinement

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).

Figures

Fig. 1.
Molecular structure of the title compound showing the atom labeling scheme and 50% probability displacement ellipsoids. Dashed lines indicate hydrogen bonds.
Fig. 2.
Packing diagram of the title compound, viewed down the a axis. Dashed lines indicate intramolecular N-H···O and intermediate intermolecular N-H···O and C-H···O hydrogen bonds in concert ...

Crystal data

C13H9ClN2O3F(000) = 568
Mr = 276.67Dx = 1.485 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 4505 reflections
a = 10.6120 (3) Åθ = 4.7–32.6°
b = 11.3314 (3) ŵ = 0.31 mm1
c = 10.8456 (3) ÅT = 110 K
β = 108.399 (3)°Chunk, colorless
V = 1237.50 (6) Å30.47 × 0.36 × 0.28 mm
Z = 4

Data collection

Oxford Diffraction Gemini R CCD diffractometer4131 independent reflections
Radiation source: fine-focus sealed tube3069 reflections with I > 2σ(I)
graphiteRint = 0.021
Detector resolution: 10.5081 pixels mm-1θmax = 32.7°, θmin = 4.7°
[var phi] and ω scansh = −15→16
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007)k = −13→16
Tmin = 0.868, Tmax = 0.916l = −16→11
8758 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.036Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.099H-atom parameters constrained
S = 1.04w = 1/[σ2(Fo2) + (0.0548P)2] where P = (Fo2 + 2Fc2)/3
4131 reflections(Δ/σ)max < 0.001
172 parametersΔρmax = 0.42 e Å3
0 restraintsΔρmin = −0.27 e Å3

Special details

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)

xyzUiso*/Ueq
Cl0.96431 (3)0.63182 (3)0.78827 (3)0.02769 (10)
O10.48712 (10)0.77733 (9)0.32532 (9)0.0350 (2)
O20.50201 (9)0.76958 (8)0.52898 (8)0.0271 (2)
O30.82129 (9)0.31290 (8)0.73196 (7)0.02303 (19)
N10.82197 (10)0.31577 (9)0.48161 (9)0.0214 (2)
H1A0.83670.28720.41200.026*
H1B0.85150.27790.55610.026*
N20.52756 (10)0.73094 (9)0.43331 (9)0.0211 (2)
C10.75466 (11)0.41681 (10)0.47433 (10)0.0162 (2)
C20.70760 (12)0.47688 (11)0.35352 (10)0.0197 (2)
H2A0.72670.44530.28020.024*
C30.63591 (12)0.57843 (11)0.33976 (10)0.0202 (2)
H3A0.60490.61690.25790.024*
C40.60840 (11)0.62550 (10)0.44837 (10)0.0169 (2)
C50.65568 (10)0.57301 (10)0.56856 (10)0.0157 (2)
H5A0.63760.60760.64100.019*
C60.73013 (10)0.46916 (10)0.58484 (10)0.0148 (2)
C70.77971 (11)0.41506 (10)0.71401 (10)0.0159 (2)
C80.77845 (11)0.48654 (10)0.83067 (9)0.0154 (2)
C90.85984 (11)0.58380 (11)0.87385 (10)0.0184 (2)
C100.86275 (12)0.64296 (11)0.98728 (11)0.0228 (3)
H10A0.91990.70881.01650.027*
C110.78122 (12)0.60456 (12)1.05687 (11)0.0240 (3)
H11A0.78270.64431.13450.029*
C120.69750 (12)0.50870 (12)1.01432 (10)0.0214 (2)
H12A0.64060.48391.06160.026*
C130.69720 (11)0.44907 (10)0.90242 (10)0.0174 (2)
H13A0.64130.38230.87440.021*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Cl0.02888 (16)0.03213 (19)0.02478 (15)−0.01301 (13)0.01233 (12)−0.00264 (12)
O10.0449 (6)0.0315 (6)0.0230 (4)0.0161 (5)0.0026 (4)0.0071 (4)
O20.0329 (5)0.0238 (5)0.0292 (4)0.0088 (4)0.0161 (4)0.0015 (4)
O30.0372 (5)0.0166 (4)0.0187 (4)0.0056 (4)0.0137 (3)0.0035 (3)
N10.0332 (5)0.0174 (5)0.0147 (4)0.0061 (4)0.0092 (4)−0.0015 (4)
N20.0217 (5)0.0192 (5)0.0209 (5)0.0027 (4)0.0045 (4)0.0014 (4)
C10.0192 (5)0.0147 (5)0.0147 (5)−0.0015 (4)0.0054 (4)−0.0022 (4)
C20.0259 (6)0.0212 (6)0.0125 (4)0.0014 (5)0.0066 (4)−0.0012 (4)
C30.0242 (5)0.0220 (6)0.0129 (5)0.0015 (5)0.0035 (4)0.0013 (4)
C40.0180 (5)0.0151 (6)0.0172 (5)0.0010 (4)0.0047 (4)−0.0006 (4)
C50.0179 (5)0.0151 (6)0.0149 (5)−0.0023 (4)0.0063 (4)−0.0030 (4)
C60.0182 (5)0.0139 (5)0.0125 (4)−0.0011 (4)0.0052 (4)−0.0006 (4)
C70.0194 (5)0.0150 (5)0.0148 (5)−0.0009 (4)0.0076 (4)0.0005 (4)
C80.0201 (5)0.0147 (5)0.0115 (4)0.0026 (4)0.0051 (4)0.0019 (4)
C90.0200 (5)0.0193 (6)0.0165 (5)−0.0007 (4)0.0066 (4)0.0009 (4)
C100.0257 (6)0.0220 (6)0.0191 (5)−0.0029 (5)0.0047 (4)−0.0050 (5)
C110.0290 (6)0.0271 (7)0.0155 (5)0.0027 (5)0.0067 (4)−0.0047 (5)
C120.0247 (6)0.0267 (7)0.0149 (5)0.0023 (5)0.0091 (4)0.0018 (4)
C130.0211 (5)0.0163 (6)0.0150 (5)−0.0004 (4)0.0060 (4)0.0016 (4)

Geometric parameters (Å, °)

Cl—C91.7426 (12)C5—C61.3972 (15)
O1—N21.2309 (13)C5—H5A0.9500
O2—N21.2326 (13)C6—C71.4663 (15)
O3—C71.2322 (14)C7—C81.5059 (15)
N1—C11.3385 (15)C8—C91.3873 (16)
N1—H1A0.8800C8—C131.3975 (15)
N1—H1B0.8800C9—C101.3927 (16)
N2—C41.4498 (15)C10—C111.3856 (18)
C1—C21.4201 (15)C10—H10A0.9500
C1—C61.4329 (14)C11—C121.3868 (18)
C2—C31.3614 (17)C11—H11A0.9500
C2—H2A0.9500C12—C131.3882 (15)
C3—C41.4052 (15)C12—H12A0.9500
C3—H3A0.9500C13—H13A0.9500
C4—C51.3754 (15)
C1—N1—H1A120.0C1—C6—C7121.40 (10)
C1—N1—H1B120.0O3—C7—C6123.11 (10)
H1A—N1—H1B120.0O3—C7—C8118.06 (9)
O1—N2—O2123.10 (11)C6—C7—C8118.83 (10)
O1—N2—C4118.38 (10)C9—C8—C13118.76 (10)
O2—N2—C4118.52 (9)C9—C8—C7122.77 (9)
N1—C1—C2119.35 (10)C13—C8—C7118.36 (10)
N1—C1—C6122.63 (10)C8—C9—C10121.23 (10)
C2—C1—C6118.00 (10)C8—C9—Cl120.08 (8)
C3—C2—C1121.87 (10)C10—C9—Cl118.67 (9)
C3—C2—H2A119.1C11—C10—C9119.10 (11)
C1—C2—H2A119.1C11—C10—H10A120.5
C2—C3—C4119.06 (10)C9—C10—H10A120.5
C2—C3—H3A120.5C10—C11—C12120.62 (11)
C4—C3—H3A120.5C10—C11—H11A119.7
C5—C4—C3121.35 (11)C12—C11—H11A119.7
C5—C4—N2119.28 (10)C11—C12—C13119.78 (11)
C3—C4—N2119.37 (10)C11—C12—H12A120.1
C4—C5—C6120.43 (10)C13—C12—H12A120.1
C4—C5—H5A119.8C12—C13—C8120.49 (11)
C6—C5—H5A119.8C12—C13—H13A119.8
C5—C6—C1119.20 (9)C8—C13—H13A119.8
C5—C6—C7119.40 (9)
N1—C1—C2—C3178.41 (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—C40.38 (18)C1—C6—C7—C8166.26 (10)
C2—C3—C4—C51.95 (18)O3—C7—C8—C9112.56 (13)
C2—C3—C4—N2−177.50 (11)C6—C7—C8—C9−68.24 (14)
O1—N2—C4—C5179.35 (11)O3—C7—C8—C13−63.73 (14)
O2—N2—C4—C5−1.01 (16)C6—C7—C8—C13115.48 (12)
O1—N2—C4—C3−1.19 (17)C13—C8—C9—C100.79 (17)
O2—N2—C4—C3178.46 (11)C7—C8—C9—C10−175.49 (11)
C3—C4—C5—C6−1.56 (17)C13—C8—C9—Cl179.06 (8)
N2—C4—C5—C6177.89 (10)C7—C8—C9—Cl2.79 (15)
C4—C5—C6—C1−1.10 (16)C8—C9—C10—C11−0.93 (18)
C4—C5—C6—C7179.85 (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—C53.28 (16)C10—C11—C12—C131.31 (19)
N1—C1—C6—C70.89 (17)C11—C12—C13—C8−1.45 (18)
C2—C1—C6—C7−177.69 (10)C9—C8—C13—C120.41 (17)
C5—C6—C7—O3164.45 (11)C7—C8—C13—C12176.85 (10)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N1—H1A···O3i0.882.223.0733 (12)164
N1—H1B···O30.882.072.7176 (12)130
N1—H1B···Clii0.882.713.4848 (10)148
C13—H13A···O2iii0.952.463.1862 (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.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: KJ2123).

References

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