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

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ISSN: 2056-9890

3-(2,4-Di­chloro­phen­yl)-5-phenyl-1,2,4-oxa­diazole

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, bSyngene International Ltd, Biocon Park, Plot Nos. 2 & 3, Bommasandra 4th Phase, Jigani Link Rd, Bangalore 560 100, India, cDepartment of Chemistry, Organic Chemistry Division, National Institute of Technology-Karnataka, Surathkal, Mangalore 575 025, India, and dDepartment of Printing, Manipal Institute of Technology, Manipal 576 104, India
*Correspondence e-mail: hkfun@usm.my

(Received 8 March 2010; accepted 11 March 2010; online 17 March 2010)

In the title compound, C14H8Cl2N2O, the dihedral angles between the plane of the oxadiazole ring and those of the benzene rings are 2.3 (1) and 9.5 (1)°. In the crystal, mol­ecules are linked into chains along the c axis by C—H⋯Cl inter­actions. These chains are stacked along the a axis.

Related literature

For the biological properties of heterocyclic compounds including oxadiazo­les, see: Andersen et al. (1994[Andersen, K. E., Jørgensen, A. S. & Braestrup, C. (1994). Eur. J. Med. Chem. 29, 393-399.]); Showell et al. (1991[Showell, G. A., Gibbons, T. L., Kneen, C. O., MacLeod, A. M., Merchant, K., Saunders, J., Freedman, S. B., Patel, S. & Baker, R. (1991). J. Med. Chem. 34, 1086-1094.]); Watjen et al. (1989[Watjen, F., Baker, R., Engelstoff, M., Herbert, R., MacLeod, A., Knight, A., Merchant, K., Moseley, J., Saunders, J., Swain, C. J., Wang, E. & Springer, J. P. (1989). J. Med. Chem. 32, 282-2291.]); Swain et al. (1991[Swain, C. J., Baker, R., Kneen, C., Moseley, J., Saunders, J., Seward, E. M., Stevenson, G., Beer, M., Stanton, J. & Watling, K. (1991). J. Med. Chem. 34, 140-151.]); Clitherow et al. (1996[Clitherow, J. W., Beswick, P., Irving, W. J., Scopes, D. I. C., Barnes, J. C., Clapham, J., Brown, J. D., Evans, D. J. & Hayes, A. G. (1996). Bioorg. Med. Chem. Lett. 6, 833-838.]). For their pharmacological and medicinal activity, see: Isloor et al. (2010[Isloor, A. M., Kalluraya, B. & Pai, K. S. (2010). Eur. J. Med. Chem. 45, 825-830]); Chandrakantha et al. (2010[Chandrakantha, B., Shetty, P., Nambiyar, V., Isloor, N. & Isloor, A. M. (2010). Eur. J. Med. Chem. 45, 1206-1210.]). For a related structure, see: Wang et al. (2006[Wang, H.-B., Liu, Z.-Q., Wang, H.-B. & Yan, X.-C. (2006). Acta Cryst. E62, o4715-o4716.]). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.]).

[Scheme 1]

Experimental

Crystal data
  • C14H8Cl2N2O

  • Mr = 291.12

  • Triclinic, [P \overline 1]

  • a = 3.8035 (2) Å

  • b = 10.9666 (7) Å

  • c = 14.6949 (9) Å

  • α = 99.044 (2)°

  • β = 91.158 (2)°

  • γ = 98.891 (2)°

  • V = 597.43 (6) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.53 mm−1

  • T = 100 K

  • 0.41 × 0.13 × 0.09 mm

Data collection
  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.809, Tmax = 0.953

  • 12084 measured reflections

  • 2692 independent reflections

  • 2355 reflections with I > 2σ(I)

  • Rint = 0.035

Refinement
  • R[F2 > 2σ(F2)] = 0.035

  • wR(F2) = 0.121

  • S = 1.14

  • 2692 reflections

  • 204 parameters

  • All H-atom parameters refined

  • Δρmax = 0.55 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
C3—H3A⋯Cl1i 0.95 (3) 2.81 (3) 3.577 (2) 138.6 (19)
Symmetry code: (i) x+1, y, z-1.

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Heterocyclic compounds are becoming increasingly important in recent years due to their pharmacological activities (Isloor et al. 2010). Nitrogen- and oxygen-containing five/six membered heterocyclic compounds are of enormous significance in the field of medicinal chemistry (Chandrakantha et al., 2010). Oxadiazoles play a very vital role in the preparation of various biologically active drugs with anti-inflammatory (Andersen et al., 1994), anti-cancer (Showell et al., 1991), anti-HIV (Watjen et al., 1989), anti-diabetic and anti-microbial (Swain et al., 1991) activities. The results of biological studies showed that oxadiazole derivatives also possess maximum anti-inflammatory, analgesic and minimum ulcerogenic and lipid per-oxidation (Clitherow et al., 1996) properties.

The geometrical parameters of (I) are within the normal range and comparable with those for a related structure (Wang et al., 2006). The mean plane of of the oxadiazole ring (C7/C8/N1/N2/O1) is almost coplanar with the C9-C14 benzene ring [dihedral angle = 2.3 (1)°] but slightly twisted with the C1-C6 benzene ring [dihedral angle = 9.5 (1)°].

The C-H···Cl (Table 1) interactions link the molecules into infinite chains along the c-axis and these chains are stacked along the a-axis.

Related literature top

For the biological properties of heterocyclic compounds including oxadiazoles, see: Andersen et al. (1994); Showell et al. (1991); Watjen et al. (1989); Swain et al. (1991); Clitherow et al. (1996). For their pharmacological and medicinal activity, see: Isloor et al. (2010); Chandrakantha et al. (2010). For a related structure, see: Wang et al. (2006). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986).

Experimental top

The title compound was prepared by heating a solution of 2,4-dichloro- N'-hydroxy-benzamidine (1 g,0.0042 mol) and benzoylchloride (0.65 g.0.004 mol) in pyridine (30 ml). The reaction mixture was heated at 114 °C for 1.5 hour and concentrated under vacuum. Further purification was done by column chromatography. The solid obtained was recrystalised using dichloromethane.Yield: 1 g (76%), Melting point 413-415 K.

Refinement top

All H atoms were located in a difference Fourier map and refined freely.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), showing 50% probability displacement ellipsoids and the atom-numbering scheme.
[Figure 2] Fig. 2. The crystal structure of (I), showing infinite chains along the c-axis.
3-(2,4-Dichlorophenyl)-5-phenyl-1,2,4-oxadiazole top
Crystal data top
C14H8Cl2N2OZ = 2
Mr = 291.12F(000) = 296
Triclinic, P1Dx = 1.618 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 3.8035 (2) ÅCell parameters from 7625 reflections
b = 10.9666 (7) Åθ = 2.5–36.0°
c = 14.6949 (9) ŵ = 0.53 mm1
α = 99.044 (2)°T = 100 K
β = 91.158 (2)°Block, colourless
γ = 98.891 (2)°0.41 × 0.13 × 0.09 mm
V = 597.43 (6) Å3
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
2692 independent reflections
Radiation source: fine-focus sealed tube2355 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.035
ϕ and ω scansθmax = 27.5°, θmin = 1.4°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
h = 44
Tmin = 0.809, Tmax = 0.953k = 1414
12084 measured reflectionsl = 1919
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)] = 0.035Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.121All H-atom parameters refined
S = 1.14 w = 1/[σ2(Fo2) + (0.0727P)2 + 0.3227P]
where P = (Fo2 + 2Fc2)/3
2692 reflections(Δ/σ)max = 0.001
204 parametersΔρmax = 0.55 e Å3
0 restraintsΔρmin = 0.39 e Å3
Crystal data top
C14H8Cl2N2Oγ = 98.891 (2)°
Mr = 291.12V = 597.43 (6) Å3
Triclinic, P1Z = 2
a = 3.8035 (2) ÅMo Kα radiation
b = 10.9666 (7) ŵ = 0.53 mm1
c = 14.6949 (9) ÅT = 100 K
α = 99.044 (2)°0.41 × 0.13 × 0.09 mm
β = 91.158 (2)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
2692 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
2355 reflections with I > 2σ(I)
Tmin = 0.809, Tmax = 0.953Rint = 0.035
12084 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0350 restraints
wR(F2) = 0.121All H-atom parameters refined
S = 1.14Δρmax = 0.55 e Å3
2692 reflectionsΔρmin = 0.39 e Å3
204 parameters
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
Cl10.67894 (14)0.17290 (4)0.56305 (3)0.02303 (17)
Cl20.74585 (13)0.52050 (4)0.34575 (3)0.01905 (16)
O11.0808 (4)0.40239 (12)0.07273 (9)0.0188 (3)
N11.1293 (4)0.22993 (14)0.12866 (10)0.0152 (3)
N20.9704 (5)0.42193 (15)0.16440 (11)0.0186 (3)
C11.3840 (5)0.31992 (18)0.09742 (13)0.0182 (4)
C21.5167 (6)0.27272 (19)0.18064 (13)0.0207 (4)
C31.5623 (5)0.14861 (19)0.19917 (13)0.0197 (4)
C41.4763 (5)0.06975 (18)0.13435 (12)0.0180 (4)
C51.3476 (5)0.11647 (17)0.05099 (12)0.0157 (4)
C61.3013 (5)0.24188 (17)0.03204 (12)0.0146 (4)
C71.1707 (5)0.28734 (17)0.05746 (12)0.0152 (4)
C81.0052 (5)0.31698 (17)0.19311 (12)0.0141 (4)
C90.9255 (5)0.28872 (16)0.28577 (12)0.0146 (4)
C100.9670 (5)0.16979 (17)0.30360 (12)0.0155 (4)
C110.8962 (5)0.13252 (18)0.38802 (13)0.0172 (4)
C120.7795 (5)0.21663 (18)0.45703 (12)0.0171 (4)
C130.7382 (5)0.33600 (18)0.44337 (12)0.0172 (4)
C140.8094 (5)0.37087 (16)0.35794 (12)0.0155 (4)
H1A1.360 (7)0.402 (3)0.0859 (17)0.026 (6)*
H2A1.572 (7)0.323 (2)0.2233 (18)0.024 (6)*
H3A1.664 (7)0.121 (2)0.2558 (18)0.029 (7)*
H4A1.483 (6)0.015 (2)0.1458 (15)0.015 (5)*
H5A1.325 (7)0.068 (2)0.0091 (17)0.020 (6)*
H10A1.028 (7)0.109 (2)0.2564 (16)0.019 (6)*
H11A0.922 (6)0.054 (2)0.3967 (15)0.014 (5)*
H13A0.635 (7)0.390 (2)0.4924 (17)0.022 (6)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0276 (3)0.0272 (3)0.0163 (2)0.0063 (2)0.00286 (18)0.00754 (18)
Cl20.0228 (3)0.0169 (2)0.0191 (2)0.00957 (18)0.00111 (17)0.00205 (17)
O10.0261 (8)0.0160 (6)0.0165 (6)0.0086 (5)0.0003 (5)0.0045 (5)
N10.0149 (8)0.0165 (7)0.0148 (7)0.0051 (6)0.0008 (6)0.0025 (6)
N20.0233 (9)0.0185 (8)0.0160 (7)0.0077 (6)0.0014 (6)0.0043 (6)
C10.0180 (10)0.0182 (9)0.0199 (9)0.0044 (7)0.0031 (7)0.0068 (7)
C20.0208 (10)0.0256 (10)0.0180 (9)0.0034 (8)0.0013 (7)0.0112 (7)
C30.0185 (10)0.0277 (10)0.0139 (8)0.0062 (8)0.0005 (7)0.0039 (7)
C40.0174 (10)0.0194 (9)0.0178 (8)0.0050 (7)0.0031 (7)0.0035 (7)
C50.0138 (9)0.0173 (8)0.0171 (8)0.0031 (7)0.0019 (6)0.0063 (7)
C60.0121 (9)0.0171 (8)0.0148 (8)0.0026 (7)0.0031 (6)0.0037 (6)
C70.0128 (9)0.0153 (8)0.0181 (8)0.0037 (7)0.0037 (6)0.0036 (6)
C80.0106 (9)0.0157 (8)0.0160 (8)0.0035 (6)0.0028 (6)0.0016 (6)
C90.0103 (9)0.0176 (9)0.0157 (8)0.0023 (7)0.0034 (6)0.0026 (6)
C100.0137 (9)0.0166 (8)0.0163 (8)0.0040 (7)0.0016 (6)0.0013 (6)
C110.0170 (10)0.0163 (9)0.0191 (8)0.0032 (7)0.0021 (7)0.0050 (7)
C120.0146 (9)0.0222 (9)0.0150 (8)0.0027 (7)0.0016 (6)0.0049 (7)
C130.0150 (9)0.0203 (9)0.0164 (8)0.0050 (7)0.0024 (7)0.0009 (7)
C140.0128 (9)0.0157 (8)0.0183 (8)0.0036 (7)0.0029 (6)0.0026 (7)
Geometric parameters (Å, º) top
Cl1—C121.7338 (18)C4—H4A0.92 (2)
Cl2—C141.7310 (18)C5—C61.399 (3)
O1—C71.344 (2)C5—H5A0.87 (2)
O1—N21.413 (2)C6—C71.457 (2)
N1—C71.303 (2)C8—C91.470 (2)
N1—C81.380 (2)C9—C101.401 (3)
N2—C81.311 (2)C9—C141.405 (3)
C1—C21.387 (3)C10—C111.385 (3)
C1—C61.394 (2)C10—H10A0.94 (2)
C1—H1A0.91 (3)C11—C121.388 (3)
C2—C31.384 (3)C11—H11A0.91 (2)
C2—H2A0.91 (3)C12—C131.387 (3)
C3—C41.395 (3)C13—C141.389 (3)
C3—H3A0.95 (3)C13—H13A0.99 (3)
C4—C51.381 (3)
C7—O1—N2106.71 (14)O1—C7—C6119.03 (16)
C7—N1—C8102.57 (15)N2—C8—N1114.69 (16)
C8—N2—O1103.00 (15)N2—C8—C9125.14 (17)
C2—C1—C6119.53 (18)N1—C8—C9120.17 (15)
C2—C1—H1A119.2 (16)C10—C9—C14117.16 (16)
C6—C1—H1A121.2 (16)C10—C9—C8117.41 (16)
C3—C2—C1120.30 (17)C14—C9—C8125.43 (16)
C3—C2—H2A119.8 (16)C11—C10—C9122.41 (17)
C1—C2—H2A119.9 (16)C11—C10—H10A116.9 (14)
C2—C3—C4120.40 (18)C9—C10—H10A120.5 (14)
C2—C3—H3A117.6 (16)C10—C11—C12118.35 (17)
C4—C3—H3A122.0 (16)C10—C11—H11A120.0 (14)
C5—C4—C3119.60 (18)C12—C11—H11A121.6 (14)
C5—C4—H4A116.9 (14)C13—C12—C11121.57 (17)
C3—C4—H4A123.3 (14)C13—C12—Cl1118.49 (15)
C4—C5—C6120.14 (17)C11—C12—Cl1119.94 (15)
C4—C5—H5A117.2 (16)C12—C13—C14118.95 (17)
C6—C5—H5A122.2 (16)C12—C13—H13A118.8 (14)
C1—C6—C5120.04 (17)C14—C13—H13A121.9 (14)
C1—C6—C7121.86 (17)C13—C14—C9121.56 (17)
C5—C6—C7118.10 (16)C13—C14—Cl2116.22 (14)
N1—C7—O1113.04 (16)C9—C14—Cl2122.21 (14)
N1—C7—C6127.93 (16)
C7—O1—N2—C80.24 (19)C7—N1—C8—N20.1 (2)
C6—C1—C2—C30.8 (3)C7—N1—C8—C9179.53 (16)
C1—C2—C3—C40.2 (3)N2—C8—C9—C10177.93 (18)
C2—C3—C4—C50.5 (3)N1—C8—C9—C102.5 (3)
C3—C4—C5—C60.5 (3)N2—C8—C9—C141.8 (3)
C2—C1—C6—C50.9 (3)N1—C8—C9—C14177.79 (17)
C2—C1—C6—C7178.25 (17)C14—C9—C10—C110.4 (3)
C4—C5—C6—C10.2 (3)C8—C9—C10—C11179.33 (17)
C4—C5—C6—C7178.94 (17)C9—C10—C11—C120.1 (3)
C8—N1—C7—O10.2 (2)C10—C11—C12—C130.9 (3)
C8—N1—C7—C6179.12 (18)C10—C11—C12—Cl1178.69 (14)
N2—O1—C7—N10.3 (2)C11—C12—C13—C141.2 (3)
N2—O1—C7—C6179.11 (15)Cl1—C12—C13—C14178.38 (14)
C1—C6—C7—N1169.98 (19)C12—C13—C14—C90.7 (3)
C5—C6—C7—N19.1 (3)C12—C13—C14—Cl2179.14 (14)
C1—C6—C7—O19.4 (3)C10—C9—C14—C130.1 (3)
C5—C6—C7—O1171.53 (16)C8—C9—C14—C13179.63 (17)
O1—N2—C8—N10.1 (2)C10—C9—C14—Cl2179.90 (14)
O1—N2—C8—C9179.68 (16)C8—C9—C14—Cl20.2 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3A···Cl1i0.95 (3)2.81 (3)3.577 (2)138.6 (19)
Symmetry code: (i) x+1, y, z1.

Experimental details

Crystal data
Chemical formulaC14H8Cl2N2O
Mr291.12
Crystal system, space groupTriclinic, P1
Temperature (K)100
a, b, c (Å)3.8035 (2), 10.9666 (7), 14.6949 (9)
α, β, γ (°)99.044 (2), 91.158 (2), 98.891 (2)
V3)597.43 (6)
Z2
Radiation typeMo Kα
µ (mm1)0.53
Crystal size (mm)0.41 × 0.13 × 0.09
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.809, 0.953
No. of measured, independent and
observed [I > 2σ(I)] reflections
12084, 2692, 2355
Rint0.035
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.035, 0.121, 1.14
No. of reflections2692
No. of parameters204
H-atom treatmentAll H-atom parameters refined
Δρmax, Δρmin (e Å3)0.55, 0.39

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3A···Cl1i0.95 (3)2.81 (3)3.577 (2)138.6 (19)
Symmetry code: (i) x+1, y, z1.
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

AMI is grateful to Professor Sandeep Sancheti, Director, National Institute of Technology-Karnataka, India for his encouragement and providing research facilities. FHK and MMR thank Universiti Sains Malaysia for the Research University Golden Goose grant (No. 1001/PFIZIK/811012).

References

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