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ISSN: 2056-9890

2-Chloro-N-(2,4-di­chloro­phen­yl)­acetamide

aDepartment of Chemistry, Mangalore University, Mangalagangotri 574 199, Mangalore, India, bInstitute of Materials Science, Darmstadt University of Technology, Petersenstrasse 23, D-64287 Darmstadt, Germany, and cFaculty of Integrated Arts and Sciences, Tokushima University, Minamijosanjima-cho, Tokushima 770-8502, Japan
*Correspondence e-mail: gowdabt@yahoo.com

(Received 15 May 2009; accepted 18 May 2009; online 23 May 2009)

The structure of the title compound, C8H6Cl3NO, contains two mol­ecules in the asymmetric unit. In each independent mol­ecule, the conformation of the N—H bond is almost syn to the ortho-chloro substituent and the conformation of the C=O bond is anti to the N—H bond. The mol­ecules in the crystal structure are linked into supra­molecular chains through N—H⋯O hydrogen bonding along the a axis.

Related literature

For the preparation of the title compound, see: Shilpa & Gowda (2007[Shilpa & Gowda, B. T. (2007). Z. Naturforsch. Teil A, 62, 84-90.]); Pies et al. (1971[Pies, W., Rager, H. & Weiss, A. (1971). Org. Magn. Reson. 3, 147-176.]). For related structures, see: Gowda, Foro & Fuess (2008[Gowda, B. T., Foro, S. & Fuess, H. (2008). Acta Cryst. E64, o419.]); Gowda, Kožíšek et al. (2008[Gowda, B. T., Kožíšek, J., Tokarčík, M. & Fuess, H. (2008). Acta Cryst. E64, o987.]); Gowda et al. (2009[Gowda, B. T., Foro, S., Terao, H. & Fuess, H. (2009). Acta Cryst. E65, o949.]).

[Scheme 1]

Experimental

Crystal data
  • C8H6Cl3NO

  • Mr = 238.49

  • Monoclinic, P 21 /c

  • a = 4.7457 (5) Å

  • b = 12.9266 (9) Å

  • c = 31.879 (4) Å

  • β = 90.12 (1)°

  • V = 1955.6 (3) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.89 mm−1

  • T = 299 K

  • 0.48 × 0.05 × 0.05 mm

Data collection
  • Oxford Diffraction Xcalibur single-crystal diffractometer with a Sapphire CCD detector

  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007[Oxford Diffraction (2007). CrysAlis RED. Oxford Diffraction Ltd, Köln, Germany.]) Tmin = 0.674, Tmax = 0.957

  • 7393 measured reflections

  • 3590 independent reflections

  • 1475 reflections with I > 2σ(I)

  • Rint = 0.077

Refinement
  • R[F2 > 2σ(F2)] = 0.080

  • wR(F2) = 0.196

  • S = 0.91

  • 3590 reflections

  • 241 parameters

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

  • Δρmax = 0.44 e Å−3

  • Δρmin = −0.39 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N⋯O1i 0.91 (7) 1.95 (7) 2.851 (7) 170 (6)
N2—H2N⋯O2i 0.77 (7) 2.11 (7) 2.872 (7) 168 (8)
Symmetry code: (i) x+1, y, z.

Data collection: CrysAlis CCD (Oxford Diffraction, 2004[Oxford Diffraction (2004). CrysAlis CCD. Oxford Diffraction Ltd, Köln, Germany.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2007[Oxford Diffraction (2007). CrysAlis RED. Oxford Diffraction Ltd, Köln, Germany.]); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

As part of a study into the effect of ring- and side-chain substitutions on the solid-state structures of aromatic amides (Gowda, Foro & Fuess, 2008; Gowda, Kožíšek et al., 2008; Gowda et al., 2009), in the present work the structure of the title compound (I) is described. There are two independent molecules in the asymmetric unit of (I), Fig. 1. The conformation of the N—H bond in each independent molecule is almost syn to the ortho-chloro substituent, similar to the syn conformation observed with respect to both the 2-chloro and 3-chloro substituents in 2-chloro-N-(2,3-dichlorophenyl)acetamide (Gowda et al., 2008a). The conformation of the C=O bond is anti to the N—H bond, also similar to that observed in 2-chloro-N-(2,3-dichlorophenyl)acetamide. The N1–H1N···O1 and N2–H2N···O2 hydrogen bonding pack the molecules into supramolecular chains aligned along the a direction (Table 1, Fig. 2).

Related literature top

For the preparation of the title compound, see: Shilpa & Gowda (2007); Pies et al. (1971). For related structures, see: Gowda, Foro & Fuess (2008); Gowda, Kožíšek et al. (2008); Gowda et al. (2009).

Experimental top

Compound (I) was prepared according to the literature method (Shilpa & Gowda, 2007). The purity of the compound was checked by determining its melting point. It was characterized by recording its infrared, NMR and NQR spectra (Shilpa & Gowda, 2007; Pies et al., 1971). Single crystals of were grown by the slow evaporation of an ethanol solution of (I) held at room temperature.

Refinement top

The N-bound H atoms were located in difference map and their positional parameters were refined freely [N—H = 0.77 (7)–0.91 (7) Å]. The other H atoms were positioned with idealized geometry using a riding model [C—H = 0.93–0.97 Å]. All H atoms were refined with isotropic displacement parameters (set to 1.2 times of the Ueq of the parent atom).

To improve considerably the values of R1, wR2, and the GoF, eight reflections (-1 8 3, 0 10 4, 1 5 3, 2 5 0, 2 5 1, 2 5 3, 4 5 0, 1 1 28) were omitted from the final refinement.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2004); cell refinement: CrysAlis RED (Oxford Diffraction, 2007); data reduction: CrysAlis RED (Oxford Diffraction, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structures of the two independent molecules in (I), showing the atom labelling scheme. The displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. Molecular packing of (I) with hydrogen bonding shown as dashed lines.
2-Chloro-N-(2,4-dichlorophenyl)acetamide top
Crystal data top
C8H6Cl3NOF(000) = 960
Mr = 238.49Dx = 1.620 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1466 reflections
a = 4.7457 (5) Åθ = 2.5–27.8°
b = 12.9266 (9) ŵ = 0.89 mm1
c = 31.879 (4) ÅT = 299 K
β = 90.12 (1)°Needle, colourless
V = 1955.6 (3) Å30.48 × 0.05 × 0.05 mm
Z = 8
Data collection top
Oxford Diffraction Xcalibur single-crystal
diffractometer with a Sapphire CCD detector
3590 independent reflections
Radiation source: fine-focus sealed tube1475 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.077
Rotation method data acquisition using ω and ϕ scansθmax = 25.3°, θmin = 2.5°
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2007)
h = 54
Tmin = 0.674, Tmax = 0.957k = 1511
7393 measured reflectionsl = 3838
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)] = 0.080Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.196H atoms treated by a mixture of independent and constrained refinement
S = 0.91 w = 1/[σ2(Fo2) + (0.0867P)2]
where P = (Fo2 + 2Fc2)/3
3590 reflections(Δ/σ)max = 0.005
241 parametersΔρmax = 0.44 e Å3
0 restraintsΔρmin = 0.39 e Å3
Crystal data top
C8H6Cl3NOV = 1955.6 (3) Å3
Mr = 238.49Z = 8
Monoclinic, P21/cMo Kα radiation
a = 4.7457 (5) ŵ = 0.89 mm1
b = 12.9266 (9) ÅT = 299 K
c = 31.879 (4) Å0.48 × 0.05 × 0.05 mm
β = 90.12 (1)°
Data collection top
Oxford Diffraction Xcalibur single-crystal
diffractometer with a Sapphire CCD detector
3590 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2007)
1475 reflections with I > 2σ(I)
Tmin = 0.674, Tmax = 0.957Rint = 0.077
7393 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0800 restraints
wR(F2) = 0.196H atoms treated by a mixture of independent and constrained refinement
S = 0.91Δρmax = 0.44 e Å3
3590 reflectionsΔρmin = 0.39 e Å3
241 parameters
Special details top

Experimental. Absorption correction: CrysAlis RED (Oxford Diffraction, 2007) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

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
Cl10.5403 (4)0.71319 (16)0.00042 (6)0.0507 (6)
Cl20.1002 (5)0.42476 (17)0.07378 (7)0.0699 (8)
Cl30.0189 (5)1.14606 (18)0.06668 (10)0.0935 (9)
O10.1586 (10)0.9317 (4)0.06073 (19)0.0672 (18)
N10.2740 (11)0.8593 (5)0.06055 (18)0.0362 (16)
H1N0.460 (14)0.876 (5)0.0583 (19)0.043*
C10.1840 (14)0.7560 (5)0.0644 (2)0.0309 (17)
C20.2935 (13)0.6804 (6)0.0379 (2)0.0330 (18)
C30.2098 (15)0.5774 (6)0.0412 (2)0.0393 (19)
H30.28620.52700.02380.047*
C40.0105 (16)0.5522 (6)0.0710 (2)0.047 (2)
C50.0950 (15)0.6242 (7)0.0982 (2)0.046 (2)
H50.22430.60490.11860.055*
C60.0095 (15)0.7241 (6)0.0950 (2)0.044 (2)
H60.08100.77270.11370.053*
C70.0950 (14)0.9405 (6)0.0596 (2)0.0386 (19)
C80.2440 (16)1.0429 (6)0.0563 (3)0.063 (3)
H8A0.32081.05050.02830.075*
H8B0.39971.04440.07610.075*
Cl41.0368 (4)0.28731 (17)0.25087 (6)0.0545 (6)
Cl50.4118 (6)0.60945 (19)0.20155 (8)0.0830 (8)
Cl60.4903 (4)0.11251 (17)0.16628 (7)0.0586 (6)
O20.3241 (10)0.1017 (4)0.1770 (2)0.0701 (18)
N20.7526 (12)0.1738 (5)0.1816 (2)0.0422 (18)
H2N0.912 (15)0.163 (6)0.181 (2)0.051*
C90.6701 (14)0.2773 (6)0.1861 (2)0.0335 (17)
C100.7879 (14)0.3385 (6)0.2170 (2)0.0381 (19)
C110.7131 (15)0.4406 (6)0.2217 (2)0.045 (2)
H110.79580.48110.24250.054*
C120.5141 (17)0.4817 (6)0.1952 (3)0.049 (2)
C130.3952 (15)0.4215 (7)0.1645 (3)0.049 (2)
H130.25950.44990.14690.059*
C140.4723 (15)0.3210 (6)0.1595 (2)0.044 (2)
H140.39220.28170.13810.052*
C150.5757 (15)0.0933 (6)0.1774 (2)0.0374 (19)
C160.7204 (15)0.0104 (6)0.1735 (3)0.062 (3)
H16A0.83070.02290.19860.074*
H16B0.84960.00790.15000.074*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0426 (12)0.0541 (13)0.0555 (13)0.0074 (10)0.0135 (9)0.0047 (11)
Cl20.0955 (19)0.0486 (15)0.0657 (16)0.0266 (12)0.0015 (13)0.0074 (12)
Cl30.0723 (18)0.0432 (15)0.165 (3)0.0070 (13)0.0398 (16)0.0038 (16)
O10.018 (3)0.043 (4)0.140 (6)0.002 (3)0.005 (3)0.001 (3)
N10.016 (3)0.034 (4)0.058 (4)0.007 (3)0.001 (3)0.000 (3)
C10.029 (4)0.030 (4)0.034 (4)0.006 (3)0.006 (3)0.002 (4)
C20.029 (4)0.045 (5)0.025 (4)0.000 (3)0.003 (3)0.006 (4)
C30.040 (5)0.028 (5)0.050 (5)0.002 (4)0.003 (4)0.004 (4)
C40.049 (5)0.051 (6)0.040 (5)0.012 (4)0.012 (4)0.004 (4)
C50.037 (5)0.055 (6)0.046 (5)0.015 (4)0.013 (4)0.002 (5)
C60.047 (5)0.050 (6)0.036 (5)0.004 (4)0.012 (4)0.007 (4)
C70.021 (4)0.035 (5)0.060 (5)0.003 (4)0.001 (4)0.008 (4)
C80.033 (5)0.043 (5)0.113 (8)0.002 (4)0.007 (4)0.001 (5)
Cl40.0407 (12)0.0626 (15)0.0602 (13)0.0013 (10)0.0087 (9)0.0003 (12)
Cl50.106 (2)0.0461 (15)0.097 (2)0.0256 (14)0.0060 (15)0.0084 (14)
Cl60.0516 (13)0.0489 (13)0.0753 (16)0.0065 (11)0.0020 (11)0.0133 (12)
O20.020 (3)0.047 (4)0.143 (6)0.010 (3)0.003 (3)0.013 (4)
N20.020 (3)0.042 (4)0.064 (4)0.002 (3)0.000 (3)0.003 (3)
C90.028 (4)0.036 (5)0.037 (4)0.000 (3)0.008 (3)0.001 (4)
C100.031 (4)0.043 (5)0.041 (5)0.001 (4)0.001 (3)0.001 (4)
C110.045 (5)0.043 (5)0.047 (5)0.003 (4)0.000 (4)0.008 (4)
C120.054 (6)0.044 (5)0.051 (5)0.012 (4)0.011 (4)0.001 (5)
C130.043 (5)0.054 (6)0.049 (5)0.007 (4)0.007 (4)0.006 (5)
C140.043 (5)0.041 (5)0.046 (5)0.005 (4)0.004 (4)0.004 (4)
C150.022 (4)0.045 (5)0.045 (5)0.002 (4)0.001 (3)0.005 (4)
C160.035 (5)0.040 (5)0.110 (8)0.004 (4)0.001 (5)0.003 (5)
Geometric parameters (Å, º) top
Cl1—C21.728 (7)Cl4—C101.730 (7)
Cl2—C41.731 (8)Cl5—C121.733 (8)
Cl3—C81.740 (8)Cl6—C161.728 (8)
O1—C71.209 (7)O2—C151.199 (7)
N1—C71.350 (9)N2—C151.344 (9)
N1—C11.407 (9)N2—C91.401 (9)
N1—H1N0.91 (7)N2—H2N0.77 (7)
C1—C21.392 (9)C9—C101.381 (9)
C1—C61.403 (9)C9—C141.385 (9)
C2—C31.393 (10)C10—C111.376 (10)
C3—C41.381 (10)C11—C121.373 (10)
C3—H30.9300C11—H110.9300
C4—C51.367 (11)C12—C131.371 (10)
C5—C61.358 (10)C13—C141.360 (11)
C5—H50.9300C13—H130.9300
C6—H60.9300C14—H140.9300
C7—C81.505 (11)C15—C161.511 (10)
C8—H8A0.9700C16—H16A0.9700
C8—H8B0.9700C16—H16B0.9700
C7—N1—C1123.3 (6)C15—N2—C9125.1 (6)
C7—N1—H1N115 (4)C15—N2—H2N118 (6)
C1—N1—H1N122 (4)C9—N2—H2N117 (6)
C2—C1—C6117.4 (7)C10—C9—C14118.4 (7)
C2—C1—N1119.9 (6)C10—C9—N2120.5 (6)
C6—C1—N1122.6 (6)C14—C9—N2121.1 (6)
C1—C2—C3121.2 (6)C11—C10—C9121.6 (7)
C1—C2—Cl1120.1 (6)C11—C10—Cl4118.3 (6)
C3—C2—Cl1118.7 (6)C9—C10—Cl4120.1 (6)
C4—C3—C2118.2 (7)C12—C11—C10118.8 (7)
C4—C3—H3120.9C12—C11—H11120.6
C2—C3—H3120.9C10—C11—H11120.6
C5—C4—C3121.8 (7)C13—C12—C11120.1 (7)
C5—C4—Cl2120.3 (7)C13—C12—Cl5120.6 (6)
C3—C4—Cl2117.9 (7)C11—C12—Cl5119.3 (7)
C6—C5—C4119.4 (7)C14—C13—C12121.1 (7)
C6—C5—H5120.3C14—C13—H13119.4
C4—C5—H5120.3C12—C13—H13119.4
C5—C6—C1121.8 (7)C13—C14—C9120.0 (7)
C5—C6—H6119.1C13—C14—H14120.0
C1—C6—H6119.1C9—C14—H14120.0
O1—C7—N1123.5 (7)O2—C15—N2123.6 (7)
O1—C7—C8123.5 (7)O2—C15—C16122.1 (7)
N1—C7—C8112.9 (6)N2—C15—C16114.3 (6)
C7—C8—Cl3111.9 (5)C15—C16—Cl6113.6 (5)
C7—C8—H8A109.2C15—C16—H16A108.8
Cl3—C8—H8A109.2Cl6—C16—H16A108.8
C7—C8—H8B109.2C15—C16—H16B108.8
Cl3—C8—H8B109.2Cl6—C16—H16B108.8
H8A—C8—H8B107.9H16A—C16—H16B107.7
C7—N1—C1—C2132.9 (7)C15—N2—C9—C10132.3 (8)
C7—N1—C1—C648.9 (10)C15—N2—C9—C1448.6 (10)
C6—C1—C2—C31.3 (9)C14—C9—C10—C110.0 (10)
N1—C1—C2—C3179.6 (6)N2—C9—C10—C11179.2 (7)
C6—C1—C2—Cl1178.2 (5)C14—C9—C10—Cl4179.8 (5)
N1—C1—C2—Cl10.1 (8)N2—C9—C10—Cl40.7 (9)
C1—C2—C3—C41.2 (10)C9—C10—C11—C120.7 (11)
Cl1—C2—C3—C4179.4 (5)Cl4—C10—C11—C12179.5 (6)
C2—C3—C4—C53.0 (11)C10—C11—C12—C130.5 (12)
C2—C3—C4—Cl2178.1 (5)C10—C11—C12—Cl5178.6 (6)
C3—C4—C5—C62.3 (11)C11—C12—C13—C140.5 (12)
Cl2—C4—C5—C6178.9 (6)Cl5—C12—C13—C14179.5 (6)
C4—C5—C6—C10.4 (11)C12—C13—C14—C91.3 (12)
C2—C1—C6—C52.1 (10)C10—C9—C14—C131.0 (11)
N1—C1—C6—C5179.7 (7)N2—C9—C14—C13179.9 (7)
C1—N1—C7—O12.1 (12)C9—N2—C15—O20.2 (12)
C1—N1—C7—C8178.6 (6)C9—N2—C15—C16179.5 (7)
O1—C7—C8—Cl314.0 (11)O2—C15—C16—Cl62.5 (11)
N1—C7—C8—Cl3166.8 (5)N2—C15—C16—Cl6177.8 (6)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O1i0.91 (7)1.95 (7)2.851 (7)170 (6)
N2—H2N···O2i0.77 (7)2.11 (7)2.872 (7)168 (8)
Symmetry code: (i) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC8H6Cl3NO
Mr238.49
Crystal system, space groupMonoclinic, P21/c
Temperature (K)299
a, b, c (Å)4.7457 (5), 12.9266 (9), 31.879 (4)
β (°) 90.12 (1)
V3)1955.6 (3)
Z8
Radiation typeMo Kα
µ (mm1)0.89
Crystal size (mm)0.48 × 0.05 × 0.05
Data collection
DiffractometerOxford Diffraction Xcalibur single-crystal
diffractometer with a Sapphire CCD detector
Absorption correctionMulti-scan
(CrysAlis RED; Oxford Diffraction, 2007)
Tmin, Tmax0.674, 0.957
No. of measured, independent and
observed [I > 2σ(I)] reflections
7393, 3590, 1475
Rint0.077
(sin θ/λ)max1)0.601
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.080, 0.196, 0.91
No. of reflections3590
No. of parameters241
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.44, 0.39

Computer programs: CrysAlis CCD (Oxford Diffraction, 2004), CrysAlis RED (Oxford Diffraction, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O1i0.91 (7)1.95 (7)2.851 (7)170 (6)
N2—H2N···O2i0.77 (7)2.11 (7)2.872 (7)168 (8)
Symmetry code: (i) x+1, y, z.
 

Acknowledgements

BTG thanks the Alexander von Humboldt Foundation, Bonn, Germany, for extension of his research fellowship.

References

First citationGowda, B. T., Foro, S. & Fuess, H. (2008). Acta Cryst. E64, o419.  Web of Science CSD CrossRef IUCr Journals Google Scholar
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