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

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ISSN: 2056-9890

{2-[(3-Bromo­benzyl­­idene)amino]-5-chloro­phen­yl}(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, C20H13BrClNO, the azomethine double bond [C=N = 1.246 (4) Å] adopts an E conformation. The bromo- and chlorophenyl rings are inclined to one another by 13.70 (11)°, and form dihedral angles of 76.68 (10) and 74.24 (7)°, respectively, with the phenyl ring. In the crystal, mol­ecules are linked by C—H⋯O hydrogen bonds to form double stranded chains propagating along the b-axis direction.

Related literature

For background information and preparation of Schiff bases, see: Khan et al. (2009[Khan, K. M., Khan, M., Ali, M., Taha, M., Rasheed, S., Perveen, S. & Choudhary, M. I. (2009). Bioorg. Med. Chem. 17, 7795-7801.]); 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.]). For the crystal structures of related Schiff bases, 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.]); Cox et al. (2008[Cox, P. J., Kechagias, D. & Kelly, O. (2008). Acta Cryst. B64, 206-216.]).

[Scheme 1]

Experimental

Crystal data
  • C20H13BrClNO

  • Mr = 398.67

  • Orthorhombic, P b c a

  • a = 16.2068 (12) Å

  • b = 7.8839 (6) Å

  • c = 27.262 (2) Å

  • V = 3483.4 (5) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 2.52 mm−1

  • T = 273 K

  • 0.52 × 0.21 × 0.15 mm

Data collection
  • Bruker SMART APEX CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2000[Bruker (2000). SADABS, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.354, Tmax = 0.704

  • 19261 measured reflections

  • 3243 independent reflections

  • 1931 reflections with I > 2σ(I)

  • Rint = 0.056

Refinement
  • R[F2 > 2σ(F2)] = 0.045

  • wR(F2) = 0.115

  • S = 1.01

  • 3243 reflections

  • 217 parameters

  • H-atom parameters constrained

  • Δρmax = 0.40 e Å−3

  • Δρmin = −0.64 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C12—H12A⋯O1i 0.93 2.44 3.346 (4) 166
C17—H17A⋯O1ii 0.93 2.51 3.428 (5) 168
Symmetry codes: (i) -x, -y-1, -z+1; (ii) x, y+1, z.

Data collection: SMART (Bruker, 2000[Bruker (2000). SADABS, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2000[Bruker (2000). SADABS, SMART and SAINT. 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

The title compound was prepared as a part of our ongoing reasearch on schiff bases (Khan et al., 2009; Aslam et al., 2011a,b; Zeb & Yousuf, 2011).

In the title compound (Fig. 1), the azomethine double bond (CN, 1.246 (4) Å) adopts an E configuration with torsion angle C6—C7—N1—C8 174.9 (3)°. The bond lengths and angle are similar as in other structurally realted compounds (Aslam et al., 2011a,b; Cox et al., 2008). In the crystal structure the molecules are arranged in parallel sheets along the b-axis via C—H···O type intermolecular hydrogen bonds (Fig. 2).

Related literature top

For background information and preparation of Schiff bases, see: Khan et al. (2009); Aslam et al. (2011a,b); Zeb & Yousuf (2011). For the crystal structures of related Schiff bases, see: Aslam et al. (2011a,b); Cox et al. (2008).

Experimental top

A mixture of 3-bromobenzaldehyde (1 mol) and 2-amino-5-chlorobenzophenone (1 mol) in ethanol (50 ml) along with 3 drops of conc. H2SO4 was refluxed 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 orange red crystals were obtained after five days. The crystalline product was collected, washed with methanol and dried to afford the title compound in 87% yield. Slow evaporation of a methanol solution afforded yellow crystals 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(C).

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 the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are presented as small spheres of arbitrary radius.
[Figure 2] Fig. 2. A view of the C—-H···O hydrogen bonds (dotted lines) in the crystal structure of the title compound. H atoms non-participating in hydrogen- bonding were omitted for clarity.
{2-[(3-Bromobenzylidene)-amino]-5-chlorophenyl}(phenyl)methanone top
Crystal data top
C20H13BrClNOF(000) = 1600
Mr = 398.67Dx = 1.520 Mg m3
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 2145 reflections
a = 16.2068 (12) Åθ = 2.5–20.5°
b = 7.8839 (6) ŵ = 2.52 mm1
c = 27.262 (2) ÅT = 273 K
V = 3483.4 (5) Å3Block, yellow
Z = 80.52 × 0.21 × 0.15 mm
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
1931 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.056
ω scanθmax = 25.5°, θmin = 1.5°
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
h = 1919
Tmin = 0.354, Tmax = 0.704k = 99
19261 measured reflectionsl = 3333
3243 independent reflections
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)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.115H-atom parameters constrained
S = 1.01 w = 1/[σ2(Fo2) + (0.0377P)2 + 3.0254P]
where P = (Fo2 + 2Fc2)/3
3243 reflections(Δ/σ)max < 0.001
217 parametersΔρmax = 0.40 e Å3
0 restraintsΔρmin = 0.64 e Å3
Crystal data top
C20H13BrClNOV = 3483.4 (5) Å3
Mr = 398.67Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 16.2068 (12) ŵ = 2.52 mm1
b = 7.8839 (6) ÅT = 273 K
c = 27.262 (2) Å0.52 × 0.21 × 0.15 mm
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
3243 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
1931 reflections with I > 2σ(I)
Tmin = 0.354, Tmax = 0.704Rint = 0.056
19261 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0450 restraints
wR(F2) = 0.115H-atom parameters constrained
S = 1.01Δρmax = 0.40 e Å3
3243 reflectionsΔρmin = 0.64 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
Br10.08907 (4)0.01989 (9)0.238025 (19)0.1197 (3)
Cl10.20842 (7)0.43108 (16)0.61666 (4)0.0784 (4)
O10.04701 (14)0.5034 (3)0.44146 (10)0.0608 (7)
N10.21723 (16)0.2133 (4)0.40923 (10)0.0480 (7)
C10.1977 (2)0.0784 (5)0.31387 (12)0.0564 (10)
H1B0.14960.10920.33020.068*
C20.1939 (3)0.0077 (5)0.26789 (13)0.0657 (11)
C30.2627 (3)0.0425 (5)0.24302 (14)0.0756 (13)
H3A0.25850.09120.21210.091*
C40.3383 (3)0.0196 (6)0.26466 (15)0.0806 (14)
H4A0.38590.05350.24840.097*
C50.3439 (2)0.0533 (6)0.31041 (14)0.0720 (12)
H5A0.39550.06910.32460.086*
C60.2739 (2)0.1034 (5)0.33568 (12)0.0508 (9)
C70.2795 (2)0.1732 (5)0.38504 (12)0.0517 (9)
H7A0.33140.18830.39900.062*
C80.22119 (19)0.2687 (4)0.45845 (11)0.0421 (8)
C90.2910 (2)0.2620 (5)0.48817 (12)0.0501 (9)
H9A0.34060.22250.47530.060*
C100.2873 (2)0.3135 (5)0.53632 (12)0.0534 (9)
H10A0.33420.30890.55590.064*
C110.2143 (2)0.3715 (5)0.55527 (12)0.0508 (9)
C120.1447 (2)0.3843 (4)0.52657 (12)0.0485 (9)
H12A0.09600.42770.53960.058*
C130.14765 (18)0.3321 (4)0.47808 (11)0.0400 (8)
C140.07325 (18)0.3588 (5)0.44606 (11)0.0431 (8)
C150.03203 (19)0.2139 (4)0.42183 (11)0.0427 (8)
C160.0429 (2)0.0504 (5)0.43778 (14)0.0581 (10)
H16A0.07760.02860.46420.070*
C180.0479 (3)0.0481 (6)0.37522 (18)0.0799 (13)
H18A0.07460.13690.35930.096*
C190.0588 (2)0.1138 (6)0.35928 (15)0.0706 (12)
H19A0.09300.13520.33260.085*
C170.0027 (2)0.0814 (6)0.41493 (17)0.0750 (12)
H17A0.00960.19200.42610.090*
C200.0199 (2)0.2447 (5)0.38228 (13)0.0553 (9)
H20A0.02810.35530.37140.066*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.1021 (4)0.1846 (7)0.0725 (4)0.0117 (4)0.0213 (3)0.0344 (4)
Cl10.0843 (7)0.0996 (9)0.0513 (5)0.0078 (6)0.0055 (5)0.0208 (6)
O10.0485 (14)0.0481 (16)0.0857 (19)0.0091 (13)0.0129 (13)0.0014 (13)
N10.0384 (15)0.059 (2)0.0470 (16)0.0057 (14)0.0019 (13)0.0018 (14)
C10.060 (2)0.066 (3)0.043 (2)0.005 (2)0.0067 (17)0.0031 (18)
C20.081 (3)0.072 (3)0.044 (2)0.002 (2)0.0013 (19)0.003 (2)
C30.109 (4)0.077 (3)0.041 (2)0.012 (3)0.012 (2)0.001 (2)
C40.087 (4)0.100 (4)0.055 (2)0.028 (3)0.024 (2)0.005 (2)
C50.060 (2)0.099 (3)0.056 (2)0.016 (2)0.0112 (19)0.006 (2)
C60.054 (2)0.056 (2)0.0417 (18)0.0070 (18)0.0043 (16)0.0089 (17)
C70.042 (2)0.065 (3)0.048 (2)0.0048 (18)0.0032 (17)0.0059 (18)
C80.0406 (18)0.041 (2)0.0442 (18)0.0010 (16)0.0002 (15)0.0022 (15)
C90.0437 (19)0.056 (2)0.051 (2)0.0079 (18)0.0024 (17)0.0021 (17)
C100.046 (2)0.063 (3)0.051 (2)0.0029 (18)0.0121 (17)0.0017 (18)
C110.055 (2)0.051 (2)0.0462 (19)0.0017 (19)0.0016 (17)0.0047 (17)
C120.0436 (19)0.049 (2)0.053 (2)0.0058 (17)0.0027 (16)0.0057 (17)
C130.0356 (18)0.0359 (19)0.0483 (19)0.0002 (15)0.0017 (14)0.0002 (15)
C140.0329 (17)0.048 (2)0.0480 (19)0.0035 (17)0.0048 (14)0.0056 (17)
C150.0356 (17)0.042 (2)0.0503 (19)0.0025 (16)0.0022 (15)0.0020 (16)
C160.046 (2)0.052 (3)0.077 (3)0.0043 (19)0.0056 (19)0.007 (2)
C180.066 (3)0.076 (3)0.098 (3)0.016 (3)0.003 (3)0.026 (3)
C190.059 (3)0.084 (3)0.069 (3)0.007 (2)0.015 (2)0.011 (2)
C170.065 (3)0.052 (3)0.109 (3)0.006 (2)0.002 (3)0.001 (2)
C200.050 (2)0.061 (2)0.055 (2)0.0024 (19)0.0054 (18)0.0049 (19)
Geometric parameters (Å, º) top
Br1—C21.896 (4)C9—H9A0.9300
Cl1—C111.741 (3)C10—C111.369 (5)
O1—C141.223 (4)C10—H10A0.9300
N1—C71.246 (4)C11—C121.377 (4)
N1—C81.412 (4)C12—C131.385 (4)
C1—C21.373 (5)C12—H12A0.9300
C1—C61.384 (5)C13—C141.503 (4)
C1—H1B0.9300C14—C151.479 (5)
C2—C31.365 (6)C15—C161.372 (5)
C3—C41.371 (6)C15—C201.389 (4)
C3—H3A0.9300C16—C171.376 (5)
C4—C51.376 (6)C16—H16A0.9300
C4—H4A0.9300C18—C191.360 (6)
C5—C61.385 (5)C18—C171.383 (6)
C5—H5A0.9300C18—H18A0.9300
C6—C71.457 (5)C19—C201.363 (5)
C7—H7A0.9300C19—H19A0.9300
C8—C91.393 (4)C17—H17A0.9300
C8—C131.399 (4)C20—H20A0.9300
C9—C101.375 (4)
C7—N1—C8123.0 (3)C10—C11—C12121.2 (3)
C2—C1—C6119.4 (4)C10—C11—Cl1120.0 (3)
C2—C1—H1B120.3C12—C11—Cl1118.8 (3)
C6—C1—H1B120.3C11—C12—C13119.4 (3)
C3—C2—C1122.3 (4)C11—C12—H12A120.3
C3—C2—Br1119.1 (3)C13—C12—H12A120.3
C1—C2—Br1118.6 (3)C12—C13—C8120.1 (3)
C2—C3—C4118.6 (4)C12—C13—C14119.0 (3)
C2—C3—H3A120.7C8—C13—C14120.7 (3)
C4—C3—H3A120.7O1—C14—C15121.1 (3)
C3—C4—C5120.2 (4)O1—C14—C13118.0 (3)
C3—C4—H4A119.9C15—C14—C13120.9 (3)
C5—C4—H4A119.9C16—C15—C20119.3 (3)
C4—C5—C6121.1 (4)C16—C15—C14121.7 (3)
C4—C5—H5A119.5C20—C15—C14119.0 (3)
C6—C5—H5A119.5C15—C16—C17120.4 (4)
C1—C6—C5118.4 (3)C15—C16—H16A119.8
C1—C6—C7120.4 (3)C17—C16—H16A119.8
C5—C6—C7121.1 (3)C19—C18—C17120.4 (4)
N1—C7—C6122.3 (3)C19—C18—H18A119.8
N1—C7—H7A118.9C17—C18—H18A119.8
C6—C7—H7A118.9C18—C19—C20120.2 (4)
C9—C8—C13118.9 (3)C18—C19—H19A119.9
C9—C8—N1125.3 (3)C20—C19—H19A119.9
C13—C8—N1115.8 (3)C16—C17—C18119.4 (4)
C10—C9—C8120.6 (3)C16—C17—H17A120.3
C10—C9—H9A119.7C18—C17—H17A120.3
C8—C9—H9A119.7C19—C20—C15120.3 (4)
C11—C10—C9119.8 (3)C19—C20—H20A119.8
C11—C10—H10A120.1C15—C20—H20A119.8
C9—C10—H10A120.1
C6—C1—C2—C31.4 (6)C11—C12—C13—C80.7 (5)
C6—C1—C2—Br1178.4 (3)C11—C12—C13—C14175.4 (3)
C1—C2—C3—C40.7 (6)C9—C8—C13—C121.1 (5)
Br1—C2—C3—C4179.0 (3)N1—C8—C13—C12177.9 (3)
C2—C3—C4—C50.3 (7)C9—C8—C13—C14173.5 (3)
C3—C4—C5—C60.6 (7)N1—C8—C13—C147.5 (4)
C2—C1—C6—C51.0 (6)C12—C13—C14—O157.2 (4)
C2—C1—C6—C7178.1 (3)C8—C13—C14—O1117.5 (4)
C4—C5—C6—C10.0 (6)C12—C13—C14—C15121.4 (3)
C4—C5—C6—C7177.1 (4)C8—C13—C14—C1563.9 (4)
C8—N1—C7—C6174.9 (3)O1—C14—C15—C16159.3 (3)
C1—C6—C7—N10.3 (6)C13—C14—C15—C1619.3 (5)
C5—C6—C7—N1177.3 (4)O1—C14—C15—C2019.9 (5)
C7—N1—C8—C910.0 (5)C13—C14—C15—C20161.6 (3)
C7—N1—C8—C13171.1 (3)C20—C15—C16—C170.1 (5)
C13—C8—C9—C101.4 (5)C14—C15—C16—C17179.0 (3)
N1—C8—C9—C10177.5 (3)C17—C18—C19—C200.1 (6)
C8—C9—C10—C110.1 (5)C15—C16—C17—C180.9 (6)
C9—C10—C11—C122.0 (6)C19—C18—C17—C160.9 (6)
C9—C10—C11—Cl1178.2 (3)C18—C19—C20—C150.8 (6)
C10—C11—C12—C132.3 (5)C16—C15—C20—C190.7 (5)
Cl1—C11—C12—C13177.9 (3)C14—C15—C20—C19179.9 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C12—H12A···O1i0.932.443.346 (4)166
C17—H17A···O1ii0.932.513.428 (5)168
Symmetry codes: (i) x, y1, z+1; (ii) x, y+1, z.

Experimental details

Crystal data
Chemical formulaC20H13BrClNO
Mr398.67
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)273
a, b, c (Å)16.2068 (12), 7.8839 (6), 27.262 (2)
V3)3483.4 (5)
Z8
Radiation typeMo Kα
µ (mm1)2.52
Crystal size (mm)0.52 × 0.21 × 0.15
Data collection
DiffractometerBruker SMART APEX CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2000)
Tmin, Tmax0.354, 0.704
No. of measured, independent and
observed [I > 2σ(I)] reflections
19261, 3243, 1931
Rint0.056
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.115, 1.01
No. of reflections3243
No. of parameters217
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.40, 0.64

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
C12—H12A···O1i0.932.443.346 (4)166
C17—H17A···O1ii0.932.513.428 (5)168
Symmetry codes: (i) x, y1, z+1; (ii) x, y+1, z.
 

Footnotes

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

Acknowledgements

MA express his gratitude to the Pakistan Council of Scientific and Industrial Research Laboratories, 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

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