organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

{5-Chloro-2-[(4-chloro­benzyl­­idene)­amino]­phen­yl}(phen­yl)methanone

aPharmaceutical Research Centre, PCSIR Laboratories Complex, Karachi, Pakistan, bDepartment of Chemistry, University of Karachi, Karachi, Pakistan, and cHEJ Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan
*Correspondence e-mail: dr.sammer.yousuf@gmail.com

(Received 8 January 2012; accepted 3 February 2012; online 10 February 2012)

In the title compound, C20H13Cl2NO, the C=N bond adopts an E conformation. The chloro-substituted rings form a dihedral angle of 11.99 (9)° with each other and form dihedral angles of 74.95 (9) and 83.26 (10)° with the unsubstituted ring. In the crystal, mol­ecules are connected into dimers by pairs of weak C—H⋯O hydrogen bonds and the dimers are arranged in columns parallel to the a axis.

Related literature

For the biological activities of Schiff base compounds, see: Solomon & Lowery (1993[Solomon, E. I. & Lowery, M. D. (1993). Science, 259, 1575-1581.]). For related structures, see: Aslam et al. (2011a[Aslam, M., Anis, I., Afza, N., Nelofar, A. & Yousuf, S. (2011a). Acta Cryst. E67, o3442-o3443.],b[Aslam, M., Anis, I., Afza, N., Nelofar, A. & Yousuf, S. (2011b). Acta Cryst. E67, o3215.]); Zeb & Yousuf (2011[Zeb, A. & Yousuf, S. (2011). Acta Cryst. E67, o2801.]).

[Scheme 1]

Experimental

Crystal data
  • C20H13Cl2NO

  • Mr = 354.21

  • Triclinic, [P \overline 1]

  • a = 7.2283 (4) Å

  • b = 10.2301 (5) Å

  • c = 11.9079 (6) Å

  • α = 100.929 (1)°

  • β = 97.318 (1)°

  • γ = 91.360 (1)°

  • V = 856.49 (8) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.38 mm−1

  • T = 273 K

  • 0.39 × 0.14 × 0.10 mm

Data collection
  • Bruker SMART APEX CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2000[Bruker (2000). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.865, Tmax = 0.963

  • 9733 measured reflections

  • 3186 independent reflections

  • 2388 reflections with I > 2σ(I)

  • Rint = 0.025

Refinement
  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.102

  • S = 1.02

  • 3186 reflections

  • 217 parameters

  • H-atom parameters constrained

  • Δρmax = 0.18 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C9—H9A⋯O1i 0.93 2.52 3.426 (2) 164
Symmetry code: (i) -x, -y, -z+2.

Data collection: SMART (Bruker, 2000[Bruker (2000). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2000[Bruker (2000). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL, PARST (Nardelli, 1995[Nardelli, M. (1995). J. Appl. Cryst. 28, 659.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Schiff bases are well known ligands in synthetic chemistry and have a wide range of bilogical activities (Solomon & Lowery, 1993). The title compound (I) (Fig. 1) is a schiff base structurally similar to our recently published compound {5-chloro-2-[(4-nitrobenzylidene)amino]phenyl}(phenyl)methanone (Aslam et al., 2011b) with a difference that the nitro group on the benzene ring (C15-C20) is replaced by a chloro group in the title compound. The torsion angle of the E configurated double bond (CN, 1.253 (2) Å) is 177.31 (15)° for C13-N1-C14-C15. The bond lengths and angles are similar to those in the previously reported structural analogue (Aslam et al., 2011b). We have published other crystal structures of this type of compound (Aslam et al., 2011a; Zeb & Yousuf, 2011). In the crystal, molecules are linked into dimers via weak C9—H9A···O1i intermolecular hydrogen bonds (symmetry code as in Table 1) and arranged in columns parallel to the a axis.

Related literature top

For the biological activities of Schiff base compounds, see: Solomon & Lowery (1993). For related structures, see: Aslam et al. (2011a,b); Zeb & Yousuf (2011).

Experimental top

The synthesis of title compound was carried out by refluxing a mixture of 4-chlorobenzaldehyde (1 mol) and 2-amino-5-chlorobenzophenone (1 mol) in ethanol (50 ml) along with 3 drops of conc. H2SO4 for 5 h at 343 K. After cooling, the mixture was concentrated to one third under reduced pressure. The concentrated reaction mixture was kept at room temperature and yellow crystals were obtained after nine days. The crystalline product was collected, washed with methanol and dried to afford the title compound in 85% yield. Slow evaporation of a methanol solution afforded yellow crystals which were suitable for single-crystal X-ray diffraction studies. All chemicals were purchased from Sigma-Aldrich.

Refinement top

H atoms were positioned geometrically with C—H = 0.93 Å, and constrained to ride on their parent atoms with Uiso(H)= 1.2Ueq(CH).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); 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), PARST (Nardelli, 1995) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) with displacement ellipsoids drawn at 30% probability level.
[Figure 2] Fig. 2. The crystal packing of (I) with hydrogen bonds shown as dashed lines. Only hydrogen atoms involved in hydrogen bonding are shown.
{5-Chloro-2-[(4-chlorobenzylidene)amino]phenyl}(phenyl)methanone top
Crystal data top
C20H13Cl2NOZ = 2
Mr = 354.21F(000) = 364
Triclinic, P1Dx = 1.373 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.2283 (4) ÅCell parameters from 2693 reflections
b = 10.2301 (5) Åθ = 2.4–25.0°
c = 11.9079 (6) ŵ = 0.38 mm1
α = 100.929 (1)°T = 273 K
β = 97.318 (1)°Block, yellow
γ = 91.360 (1)°0.39 × 0.14 × 0.10 mm
V = 856.49 (8) Å3
Data collection top
Bruker SMART APEX CCD
diffractometer
3186 independent reflections
Radiation source: fine-focus sealed tube2388 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.025
ω scansθmax = 25.5°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
h = 88
Tmin = 0.865, Tmax = 0.963k = 1212
9733 measured reflectionsl = 1414
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)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.102H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0503P)2 + 0.1325P]
where P = (Fo2 + 2Fc2)/3
3186 reflections(Δ/σ)max = 0.001
217 parametersΔρmax = 0.18 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C20H13Cl2NOγ = 91.360 (1)°
Mr = 354.21V = 856.49 (8) Å3
Triclinic, P1Z = 2
a = 7.2283 (4) ÅMo Kα radiation
b = 10.2301 (5) ŵ = 0.38 mm1
c = 11.9079 (6) ÅT = 273 K
α = 100.929 (1)°0.39 × 0.14 × 0.10 mm
β = 97.318 (1)°
Data collection top
Bruker SMART APEX CCD
diffractometer
3186 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
2388 reflections with I > 2σ(I)
Tmin = 0.865, Tmax = 0.963Rint = 0.025
9733 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0370 restraints
wR(F2) = 0.102H-atom parameters constrained
S = 1.02Δρmax = 0.18 e Å3
3186 reflectionsΔρmin = 0.23 e Å3
217 parameters
Special details top

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
Cl10.21952 (9)0.72197 (6)0.48534 (5)0.0772 (2)
Cl20.26120 (8)0.21797 (7)1.37525 (4)0.0772 (2)
O10.06787 (19)0.12992 (15)0.92259 (12)0.0703 (4)
N10.2217 (2)0.43376 (15)0.94686 (13)0.0534 (4)
C10.3968 (3)0.1501 (2)0.85494 (17)0.0593 (5)
H1B0.45880.16800.93000.071*
C20.4979 (3)0.1263 (2)0.7624 (2)0.0747 (7)
H2A0.62750.12570.77530.090*
C30.4060 (4)0.1037 (2)0.65140 (19)0.0715 (6)
H3A0.47400.09110.58930.086*
C40.2164 (3)0.0997 (2)0.63220 (17)0.0640 (6)
H4A0.15490.08330.55700.077*
C50.1152 (3)0.12004 (19)0.72373 (16)0.0542 (5)
H5A0.01460.11540.71000.065*
C60.2049 (2)0.14729 (16)0.83616 (14)0.0448 (4)
C70.0923 (3)0.17452 (17)0.93309 (15)0.0465 (4)
C80.1764 (2)0.25790 (17)1.04654 (14)0.0443 (4)
C90.1823 (2)0.20517 (19)1.14596 (15)0.0507 (4)
H9A0.14100.11741.14190.061*
C100.2499 (3)0.2842 (2)1.25056 (15)0.0520 (5)
C110.3079 (3)0.4151 (2)1.25924 (16)0.0566 (5)
H11A0.35170.46741.33090.068*
C120.3006 (3)0.4679 (2)1.16108 (16)0.0560 (5)
H12A0.33970.55641.16680.067*
C130.2355 (2)0.39071 (17)1.05307 (14)0.0453 (4)
C140.2384 (2)0.55370 (18)0.93892 (15)0.0483 (4)
H14A0.25590.61861.00610.058*
C150.2314 (2)0.59480 (17)0.82787 (15)0.0448 (4)
C160.2588 (3)0.72787 (18)0.82228 (16)0.0522 (5)
H16A0.27870.79150.89020.063*
C170.2569 (3)0.76737 (19)0.71788 (17)0.0550 (5)
H17A0.27630.85680.71510.066*
C180.2260 (3)0.6728 (2)0.61789 (16)0.0519 (5)
C190.1977 (3)0.5396 (2)0.62006 (17)0.0595 (5)
H19A0.17680.47660.55180.071*
C200.2007 (3)0.50153 (19)0.72493 (16)0.0559 (5)
H20A0.18190.41190.72720.067*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.1037 (5)0.0795 (4)0.0541 (3)0.0031 (3)0.0087 (3)0.0294 (3)
Cl20.0884 (4)0.1037 (5)0.0477 (3)0.0080 (3)0.0099 (3)0.0346 (3)
O10.0583 (9)0.0847 (10)0.0620 (9)0.0190 (8)0.0089 (7)0.0014 (7)
N10.0718 (11)0.0451 (9)0.0437 (9)0.0017 (7)0.0051 (7)0.0119 (7)
C10.0574 (12)0.0635 (13)0.0513 (11)0.0004 (10)0.0015 (9)0.0013 (9)
C20.0594 (13)0.0807 (16)0.0788 (16)0.0021 (11)0.0199 (12)0.0038 (12)
C30.0960 (18)0.0620 (13)0.0584 (13)0.0072 (12)0.0325 (12)0.0032 (10)
C40.0888 (16)0.0603 (13)0.0429 (11)0.0038 (11)0.0063 (10)0.0130 (9)
C50.0624 (12)0.0537 (11)0.0463 (10)0.0001 (9)0.0008 (9)0.0136 (8)
C60.0529 (10)0.0389 (9)0.0415 (9)0.0020 (8)0.0026 (8)0.0081 (7)
C70.0496 (10)0.0441 (10)0.0461 (10)0.0027 (8)0.0024 (8)0.0125 (8)
C80.0453 (9)0.0475 (10)0.0407 (9)0.0010 (8)0.0077 (7)0.0091 (8)
C90.0518 (10)0.0567 (11)0.0474 (10)0.0009 (9)0.0094 (8)0.0181 (9)
C100.0489 (10)0.0710 (13)0.0404 (10)0.0094 (9)0.0077 (8)0.0196 (9)
C110.0618 (12)0.0670 (13)0.0385 (10)0.0059 (10)0.0053 (8)0.0044 (9)
C120.0702 (13)0.0476 (11)0.0475 (11)0.0010 (9)0.0056 (9)0.0044 (9)
C130.0490 (10)0.0479 (10)0.0398 (9)0.0030 (8)0.0074 (8)0.0092 (8)
C140.0542 (11)0.0454 (11)0.0445 (10)0.0002 (8)0.0061 (8)0.0072 (8)
C150.0428 (9)0.0440 (10)0.0482 (10)0.0010 (7)0.0063 (8)0.0107 (8)
C160.0638 (12)0.0421 (10)0.0499 (11)0.0017 (8)0.0069 (9)0.0076 (8)
C170.0655 (12)0.0439 (10)0.0581 (12)0.0002 (9)0.0082 (9)0.0163 (9)
C180.0523 (10)0.0586 (12)0.0480 (11)0.0010 (9)0.0063 (8)0.0190 (9)
C190.0775 (13)0.0526 (12)0.0459 (11)0.0047 (10)0.0041 (9)0.0069 (9)
C200.0710 (13)0.0426 (10)0.0539 (11)0.0041 (9)0.0052 (9)0.0119 (9)
Geometric parameters (Å, º) top
Cl1—C181.7406 (18)C9—C101.374 (3)
Cl2—C101.7389 (18)C9—H9A0.9300
O1—C71.217 (2)C10—C111.375 (3)
N1—C141.253 (2)C11—C121.373 (3)
N1—C131.409 (2)C11—H11A0.9300
C1—C61.375 (3)C12—C131.394 (2)
C1—C21.385 (3)C12—H12A0.9300
C1—H1B0.9300C14—C151.457 (2)
C2—C31.377 (3)C14—H14A0.9300
C2—H2A0.9300C15—C161.386 (2)
C3—C41.359 (3)C15—C201.393 (3)
C3—H3A0.9300C16—C171.377 (3)
C4—C51.375 (3)C16—H16A0.9300
C4—H4A0.9300C17—C181.374 (3)
C5—C61.385 (2)C17—H17A0.9300
C5—H5A0.9300C18—C191.379 (3)
C6—C71.483 (2)C19—C201.375 (3)
C7—C81.501 (2)C19—H19A0.9300
C8—C91.387 (2)C20—H20A0.9300
C8—C131.399 (2)
C14—N1—C13123.34 (16)C12—C11—C10119.37 (17)
C6—C1—C2120.21 (19)C12—C11—H11A120.3
C6—C1—H1B119.9C10—C11—H11A120.3
C2—C1—H1B119.9C11—C12—C13120.96 (18)
C3—C2—C1119.8 (2)C11—C12—H12A119.5
C3—C2—H2A120.1C13—C12—H12A119.5
C1—C2—H2A120.1C12—C13—C8118.58 (16)
C4—C3—C2120.3 (2)C12—C13—N1126.03 (17)
C4—C3—H3A119.9C8—C13—N1115.39 (15)
C2—C3—H3A119.9N1—C14—C15122.11 (17)
C3—C4—C5120.1 (2)N1—C14—H14A118.9
C3—C4—H4A119.9C15—C14—H14A118.9
C5—C4—H4A119.9C16—C15—C20118.33 (17)
C4—C5—C6120.57 (19)C16—C15—C14120.65 (16)
C4—C5—H5A119.7C20—C15—C14121.01 (16)
C6—C5—H5A119.7C17—C16—C15121.11 (17)
C1—C6—C5118.97 (17)C17—C16—H16A119.4
C1—C6—C7121.64 (16)C15—C16—H16A119.4
C5—C6—C7119.38 (16)C18—C17—C16119.08 (17)
O1—C7—C6121.13 (16)C18—C17—H17A120.5
O1—C7—C8119.03 (16)C16—C17—H17A120.5
C6—C7—C8119.84 (15)C17—C18—C19121.44 (17)
C9—C8—C13120.33 (16)C17—C18—Cl1119.46 (15)
C9—C8—C7119.33 (16)C19—C18—Cl1119.10 (15)
C13—C8—C7120.17 (15)C20—C19—C18118.84 (18)
C10—C9—C8119.20 (17)C20—C19—H19A120.6
C10—C9—H9A120.4C18—C19—H19A120.6
C8—C9—H9A120.4C19—C20—C15121.20 (17)
C9—C10—C11121.53 (17)C19—C20—H20A119.4
C9—C10—Cl2119.45 (16)C15—C20—H20A119.4
C11—C10—Cl2119.01 (15)
C6—C1—C2—C31.9 (3)C10—C11—C12—C130.0 (3)
C1—C2—C3—C42.4 (4)C11—C12—C13—C80.3 (3)
C2—C3—C4—C50.8 (3)C11—C12—C13—N1180.00 (17)
C3—C4—C5—C61.3 (3)C9—C8—C13—C120.3 (3)
C2—C1—C6—C50.2 (3)C7—C8—C13—C12175.50 (16)
C2—C1—C6—C7178.95 (19)C9—C8—C13—N1179.44 (15)
C4—C5—C6—C11.8 (3)C7—C8—C13—N14.2 (2)
C4—C5—C6—C7177.37 (17)C14—N1—C13—C1212.0 (3)
C1—C6—C7—O1154.66 (19)C14—N1—C13—C8167.63 (18)
C5—C6—C7—O126.2 (3)C13—N1—C14—C15177.31 (15)
C1—C6—C7—C825.1 (3)N1—C14—C15—C16177.10 (18)
C5—C6—C7—C8154.06 (16)N1—C14—C15—C201.7 (3)
O1—C7—C8—C957.0 (2)C20—C15—C16—C170.4 (3)
C6—C7—C8—C9122.72 (18)C14—C15—C16—C17178.42 (16)
O1—C7—C8—C13118.3 (2)C15—C16—C17—C180.5 (3)
C6—C7—C8—C1362.0 (2)C16—C17—C18—C190.3 (3)
C13—C8—C9—C101.1 (3)C16—C17—C18—Cl1178.94 (14)
C7—C8—C9—C10176.41 (16)C17—C18—C19—C200.0 (3)
C8—C9—C10—C111.4 (3)Cl1—C18—C19—C20179.23 (15)
C8—C9—C10—Cl2178.96 (13)C18—C19—C20—C150.1 (3)
C9—C10—C11—C120.9 (3)C16—C15—C20—C190.1 (3)
Cl2—C10—C11—C12179.54 (14)C14—C15—C20—C19178.70 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C9—H9A···O1i0.932.523.426 (2)164
Symmetry code: (i) x, y, z+2.

Experimental details

Crystal data
Chemical formulaC20H13Cl2NO
Mr354.21
Crystal system, space groupTriclinic, P1
Temperature (K)273
a, b, c (Å)7.2283 (4), 10.2301 (5), 11.9079 (6)
α, β, γ (°)100.929 (1), 97.318 (1), 91.360 (1)
V3)856.49 (8)
Z2
Radiation typeMo Kα
µ (mm1)0.38
Crystal size (mm)0.39 × 0.14 × 0.10
Data collection
DiffractometerBruker SMART APEX CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2000)
Tmin, Tmax0.865, 0.963
No. of measured, independent and
observed [I > 2σ(I)] reflections
9733, 3186, 2388
Rint0.025
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.102, 1.02
No. of reflections3186
No. of parameters217
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.18, 0.23

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), PARST (Nardelli, 1995) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C9—H9A···O1i0.93002.52003.426 (2)164.00
Symmetry code: (i) x, y, z+2.
 

Footnotes

Additional correspondence author, e-mail: maslamchemist@hotmail.com.

Acknowledgements

MA expresses his gratitude to the Pakistan Council of Scientific and Industrial Research Laboratories Complex, Karachi, the Department of Chemistry, University of Karachi, and the HEJ Research Institute of Chemistry, Inter­national Center for Chemical and Biological Sciences, University of Karachi, for providing financial support, research facilities and X-ray diffraction facilities, respectively.

References

First citationAslam, M., Anis, I., Afza, N., Nelofar, A. & Yousuf, S. (2011a). Acta Cryst. E67, o3442–o3443.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
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