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

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ISSN: 2056-9890

2,3-Di­bromo-3-phenyl-1-(3-phenyl­sydnon-4-yl)propan-1-one

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri, Mangalore 574 199, India
*Correspondence e-mail: hkfun@usm.my

(Received 28 February 2011; accepted 3 March 2011; online 9 March 2011)

In the title compound [systematic name: 4-(2,3-dibromo-3-phenyl­propano­yl)-3-phenyl-1,2,3-oxadiazol-3-ylium-5-olate], C17H12Br2N2O3, the oxadiazole ring is essentially planar, with a maximum deviation of 0.001 (3) Å. The central oxadiazole ring makes dihedral angles of 73.3 (2) and 29.0 (2)° with the adjacent and remote phenyl rings, respectively. In the crystal, adjacent mol­ecules are connected by C—H⋯O hydrogen bonds, forming a supra­molecular chain along the c axis. There is an intra­molecular C—H⋯O hydrogen bond, which generates an S(6) ring motif.

Related literature

For applications of sydnones, see: Rai et al. (2008[Rai, N. S., Kalluraya, B., Lingappa, B., Shenoy, S. & Puranic, V. G. (2008). Eur. J. Med. Chem. 43, 1715-1720.]); Jyothi et al. (2008[Jyothi, C. H., Girisha, K. S., Adithya, A. & Kalluraya, B. (2008). Eur. J. Med. Chem. 43, 2831-2834.]). For details of chalcones, see: Rai et al. (2007[Rai, N. S., Kalluraya, B. & Lingappa, B. (2007). Synth. Commun. 37, 2267-2273.]).

[Scheme 1]

Experimental

Crystal data
  • C17H12Br2N2O3

  • Mr = 452.11

  • Monoclinic, P 21 /c

  • a = 11.9109 (3) Å

  • b = 17.5018 (3) Å

  • c = 8.5365 (2) Å

  • β = 94.960 (1)°

  • V = 1772.87 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 4.59 mm−1

  • T = 296 K

  • 0.30 × 0.20 × 0.04 mm

Data collection
  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.341, Tmax = 0.849

  • 23853 measured reflections

  • 4082 independent reflections

  • 1912 reflections with I > 2σ(I)

  • Rint = 0.068

Refinement
  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.104

  • S = 0.98

  • 4082 reflections

  • 217 parameters

  • H-atom parameters constrained

  • Δρmax = 0.48 e Å−3

  • Δρmin = −0.44 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C10—H10A⋯O2 0.98 2.35 3.028 (6) 126
C13—H13A⋯O2i 0.93 2.49 3.312 (6) 147
Symmetry code: (i) x, y, z+1.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2 and SAINT. 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

Sydnones constitute a well-defined class of mesoionic compounds that contain the 1,2,3-oxadiazole ring system. The study of sydnones still remains a field of interest because of their electronic structure and also because of the varied types of biological activities (Rai et al., 2008). Recently, sydnone derivatives were found to exhibit promising anti-microbial properties (Jyothi et al., 2008). Chalcones were obtained by the base-catalyzed condensation of 4-acetyl-3-aryl sydnones with aromatic aldehydes in alcoholic medium employing sodium hydroxide as catalyst at 0–5 °C. Bromination of chalcones with bromine in glacial acetic acid afforded dibromo chalcones (Rai et al., 2007).

The molecular structure of the title compound is shown in Fig. 1. The oxadiazole (N1/N2/O1/C7/C8) ring is essentially planar, with a maximum deviation of 0.001 (3) Å for atom O1. The central oxadiazole (N1/N2/O1/C7/C8) ring makes dihedral angles of 73.3 (2)° and 29.0 (2)° with the attached phenyl (C1–C6) and the terminal phenyl (C12–C17) rings, respectively.

In the crystal, (Fig. 2), the adjacent molecules are connected by intra and intermolecular C10—H10A···O2 and C13—H13A···O2 (Table 1) hydrogen bonds forming supramolecular chains along the c-axis. There is an intramolecular C—H···O hydrogen bond, which generates an S(6) ring motif.

Related literature top

For applications of sydnones, see: Rai et al. (2008); Jyothi et al. (2008). For details of chalcones, see: Rai et al. (2007).

Experimental top

1-(31-Phenylsydnon-41-yl)-3-(phenyl)-propen-1-one (0.01 mol) was dissolved in glacial acetic acid (2–30 ml) by gentle warming. A solution of bromine in glacial acetic acid (30% w/v) was added to it with constant stirring till the yellow color of the bromine persisted. The reaction mixture was stirred at room temperature for 1-2 hours. The solid which separated was filtered, washed with methanol and dried. It was then recrystallized from ethanol. Crystals suitable for X-ray analysis were obtained from 1:2 mixtures of DMF and ethanol by slow evaporation.

Refinement top

All H atoms were positioned geometrically (C—H = 0.93 Å) and were refined using a riding model, with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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 asymmetric unit of the title compound, showing 30% probability displacement ellipsoids and the atom-numbering scheme. The intramolecular hydrogen bond is shown as a dashed line.
[Figure 2] Fig. 2. The crystal packing of the title compound.
4-(2,3-dibromo-3-phenylpropanoyl)-3-phenyl-1,2,3-oxadiazol-3-ylium-5-olate top
Crystal data top
C17H12Br2N2O3F(000) = 888
Mr = 452.11Dx = 1.694 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3028 reflections
a = 11.9109 (3) Åθ = 2.3–19.9°
b = 17.5018 (3) ŵ = 4.59 mm1
c = 8.5365 (2) ÅT = 296 K
β = 94.960 (1)°Plate, colourless
V = 1772.87 (7) Å30.30 × 0.20 × 0.04 mm
Z = 4
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
4082 independent reflections
Radiation source: fine-focus sealed tube1912 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.068
ϕ and ω scansθmax = 27.6°, θmin = 1.7°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
h = 1515
Tmin = 0.341, Tmax = 0.849k = 2222
23853 measured reflectionsl = 1111
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)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.104H-atom parameters constrained
S = 0.98 w = 1/[σ2(Fo2) + (0.0352P)2 + 0.6409P]
where P = (Fo2 + 2Fc2)/3
4082 reflections(Δ/σ)max = 0.001
217 parametersΔρmax = 0.48 e Å3
0 restraintsΔρmin = 0.44 e Å3
Crystal data top
C17H12Br2N2O3V = 1772.87 (7) Å3
Mr = 452.11Z = 4
Monoclinic, P21/cMo Kα radiation
a = 11.9109 (3) ŵ = 4.59 mm1
b = 17.5018 (3) ÅT = 296 K
c = 8.5365 (2) Å0.30 × 0.20 × 0.04 mm
β = 94.960 (1)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
4082 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
1912 reflections with I > 2σ(I)
Tmin = 0.341, Tmax = 0.849Rint = 0.068
23853 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.104H-atom parameters constrained
S = 0.98Δρmax = 0.48 e Å3
4082 reflectionsΔρmin = 0.44 e Å3
217 parameters
Special details top

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
Br10.16038 (4)1.00790 (2)0.96635 (6)0.0826 (2)
Br20.24594 (5)0.75050 (3)0.96598 (7)0.1118 (3)
O10.0435 (3)0.92146 (17)0.4180 (4)0.0871 (9)
O20.2052 (3)0.94860 (17)0.5666 (4)0.0889 (10)
O30.0007 (3)0.8462 (2)0.9185 (4)0.0943 (10)
N10.0551 (3)0.87006 (17)0.5834 (5)0.0648 (9)
N20.0581 (4)0.8894 (2)0.4355 (5)0.0855 (11)
C10.1583 (4)0.7596 (2)0.6667 (6)0.0827 (14)
H1A0.09490.72950.65650.099*
C20.2551 (4)0.7276 (3)0.7140 (6)0.0939 (16)
H2A0.25740.67570.73650.113*
C30.3477 (5)0.7719 (3)0.7279 (6)0.0957 (16)
H3A0.41330.75020.75960.115*
C40.3441 (5)0.8483 (3)0.6951 (7)0.1000 (16)
H4A0.40760.87830.70480.120*
C50.2478 (4)0.8815 (3)0.6481 (6)0.0827 (14)
H5A0.24520.93340.62580.099*
C60.1562 (4)0.8357 (2)0.6350 (5)0.0639 (11)
C70.1121 (5)0.9216 (2)0.5614 (6)0.0722 (12)
C80.0427 (4)0.8868 (2)0.6687 (5)0.0615 (11)
C90.0669 (4)0.8733 (2)0.8348 (6)0.0695 (12)
C100.1842 (4)0.8990 (2)0.9026 (6)0.0768 (13)
H10A0.23680.89720.82050.092*
C110.2311 (4)0.8574 (3)1.0407 (6)0.0820 (13)
H11A0.17670.85851.12050.098*
C120.3433 (4)0.8850 (2)1.1137 (6)0.0664 (11)
C130.3544 (4)0.9064 (2)1.2683 (6)0.0800 (13)
H13A0.29240.90421.32730.096*
C140.4564 (6)0.9312 (3)1.3369 (7)0.0982 (17)
H14A0.46380.94461.44270.118*
C150.5474 (5)0.9361 (3)1.2496 (9)0.0971 (17)
H15A0.61650.95311.29580.116*
C160.5364 (4)0.9164 (3)1.0977 (8)0.0981 (17)
H16A0.59810.92071.03850.118*
C170.4361 (4)0.8899 (3)1.0275 (6)0.0888 (14)
H17A0.43040.87540.92230.107*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0582 (3)0.0681 (3)0.1219 (5)0.0028 (2)0.0096 (3)0.0066 (3)
Br20.1595 (6)0.0592 (3)0.1144 (5)0.0146 (3)0.0012 (4)0.0116 (3)
O10.106 (3)0.087 (2)0.071 (2)0.0081 (19)0.022 (2)0.0099 (17)
O20.092 (2)0.086 (2)0.095 (3)0.0176 (18)0.042 (2)0.0054 (18)
O30.085 (2)0.131 (3)0.068 (2)0.051 (2)0.0126 (19)0.005 (2)
N10.075 (3)0.057 (2)0.063 (3)0.0025 (18)0.008 (2)0.0008 (18)
N20.096 (3)0.091 (3)0.069 (3)0.004 (2)0.005 (3)0.007 (2)
C10.076 (3)0.061 (3)0.109 (4)0.003 (2)0.005 (3)0.001 (3)
C20.080 (4)0.069 (3)0.129 (5)0.020 (3)0.011 (3)0.010 (3)
C30.080 (4)0.098 (4)0.108 (4)0.023 (3)0.003 (3)0.007 (3)
C40.086 (4)0.091 (4)0.125 (5)0.015 (3)0.024 (3)0.004 (3)
C50.083 (3)0.065 (3)0.101 (4)0.001 (3)0.013 (3)0.006 (3)
C60.065 (3)0.061 (3)0.065 (3)0.006 (2)0.000 (2)0.000 (2)
C70.088 (4)0.055 (3)0.076 (4)0.002 (2)0.021 (3)0.002 (2)
C80.067 (3)0.064 (2)0.055 (3)0.009 (2)0.014 (3)0.000 (2)
C90.063 (3)0.074 (3)0.072 (4)0.022 (2)0.012 (3)0.008 (2)
C100.066 (3)0.087 (3)0.079 (3)0.014 (2)0.017 (3)0.004 (3)
C110.082 (3)0.083 (3)0.083 (4)0.019 (3)0.015 (3)0.000 (3)
C120.067 (3)0.068 (3)0.064 (3)0.005 (2)0.009 (3)0.000 (2)
C130.094 (4)0.067 (3)0.080 (4)0.010 (2)0.017 (3)0.011 (2)
C140.127 (5)0.081 (3)0.084 (4)0.012 (3)0.006 (4)0.012 (3)
C150.077 (4)0.078 (3)0.130 (6)0.007 (3)0.025 (4)0.003 (3)
C160.061 (3)0.116 (4)0.116 (5)0.003 (3)0.001 (4)0.017 (4)
C170.070 (3)0.115 (4)0.082 (4)0.009 (3)0.014 (3)0.006 (3)
Geometric parameters (Å, º) top
Br1—C102.008 (4)C5—H5A0.9300
Br2—C111.990 (5)C7—C81.422 (6)
O1—N21.354 (5)C8—C91.442 (6)
O1—C71.411 (5)C9—C101.533 (6)
O2—C71.203 (5)C10—C111.455 (6)
O3—C91.206 (5)C10—H10A0.9800
N1—N21.304 (5)C11—C121.505 (6)
N1—C81.351 (5)C11—H11A0.9800
N1—C61.448 (5)C12—C131.367 (6)
C1—C61.361 (5)C12—C171.382 (6)
C1—C21.374 (6)C13—C141.372 (7)
C1—H1A0.9300C13—H13A0.9300
C2—C31.361 (6)C14—C151.370 (7)
C2—H2A0.9300C14—H14A0.9300
C3—C41.369 (6)C15—C161.338 (7)
C3—H3A0.9300C15—H15A0.9300
C4—C51.376 (6)C16—C171.370 (7)
C4—H4A0.9300C16—H16A0.9300
C5—C61.365 (5)C17—H17A0.9300
N2—O1—C7111.2 (4)C8—C9—C10114.9 (4)
N2—N1—C8114.6 (4)C11—C10—C9115.6 (4)
N2—N1—C6116.6 (4)C11—C10—Br1108.0 (3)
C8—N1—C6128.8 (4)C9—C10—Br1103.6 (3)
N1—N2—O1105.3 (4)C11—C10—H10A109.8
C6—C1—C2119.2 (4)C9—C10—H10A109.8
C6—C1—H1A120.4Br1—C10—H10A109.8
C2—C1—H1A120.4C10—C11—C12116.1 (4)
C3—C2—C1120.1 (5)C10—C11—Br2104.4 (3)
C3—C2—H2A119.9C12—C11—Br2109.5 (3)
C1—C2—H2A119.9C10—C11—H11A108.8
C2—C3—C4119.9 (5)C12—C11—H11A108.8
C2—C3—H3A120.1Br2—C11—H11A108.8
C4—C3—H3A120.1C13—C12—C17118.8 (4)
C3—C4—C5120.9 (5)C13—C12—C11119.8 (4)
C3—C4—H4A119.5C17—C12—C11121.4 (4)
C5—C4—H4A119.5C12—C13—C14120.4 (5)
C6—C5—C4118.0 (4)C12—C13—H13A119.8
C6—C5—H5A121.0C14—C13—H13A119.8
C4—C5—H5A121.0C15—C14—C13120.0 (5)
C1—C6—C5122.0 (4)C15—C14—H14A120.0
C1—C6—N1119.8 (4)C13—C14—H14A120.0
C5—C6—N1118.2 (4)C16—C15—C14119.7 (5)
O2—C7—O1119.7 (5)C16—C15—H15A120.2
O2—C7—C8136.8 (5)C14—C15—H15A120.2
O1—C7—C8103.5 (4)C15—C16—C17121.3 (5)
N1—C8—C7105.5 (4)C15—C16—H16A119.3
N1—C8—C9125.7 (4)C17—C16—H16A119.3
C7—C8—C9128.7 (4)C16—C17—C12119.7 (5)
O3—C9—C8124.2 (4)C16—C17—H17A120.2
O3—C9—C10120.9 (4)C12—C17—H17A120.2
C8—N1—N2—O10.1 (5)N1—C8—C9—O31.4 (7)
C6—N1—N2—O1178.4 (3)C7—C8—C9—O3176.6 (4)
C7—O1—N2—N10.1 (4)N1—C8—C9—C10179.0 (4)
C6—C1—C2—C30.3 (8)C7—C8—C9—C101.1 (6)
C1—C2—C3—C40.2 (8)O3—C9—C10—C1129.5 (6)
C2—C3—C4—C50.0 (8)C8—C9—C10—C11152.7 (4)
C3—C4—C5—C60.0 (8)O3—C9—C10—Br188.4 (4)
C2—C1—C6—C50.3 (7)C8—C9—C10—Br189.4 (4)
C2—C1—C6—N1179.3 (4)C9—C10—C11—C12176.7 (4)
C4—C5—C6—C10.1 (7)Br1—C10—C11—C1261.3 (5)
C4—C5—C6—N1179.1 (4)C9—C10—C11—Br262.6 (4)
N2—N1—C6—C1106.8 (5)Br1—C10—C11—Br2178.07 (17)
C8—N1—C6—C174.9 (6)C10—C11—C12—C13123.0 (5)
N2—N1—C6—C572.2 (5)Br2—C11—C12—C13119.1 (4)
C8—N1—C6—C5106.1 (5)C10—C11—C12—C1756.4 (6)
N2—O1—C7—O2179.6 (4)Br2—C11—C12—C1761.6 (5)
N2—O1—C7—C80.1 (4)C17—C12—C13—C141.1 (7)
N2—N1—C8—C70.0 (5)C11—C12—C13—C14179.6 (4)
C6—N1—C8—C7178.3 (3)C12—C13—C14—C151.4 (7)
N2—N1—C8—C9178.3 (4)C13—C14—C15—C160.3 (8)
C6—N1—C8—C90.1 (6)C14—C15—C16—C171.1 (8)
O2—C7—C8—N1179.3 (5)C15—C16—C17—C121.4 (8)
O1—C7—C8—N10.1 (4)C13—C12—C17—C160.3 (7)
O2—C7—C8—C91.0 (8)C11—C12—C17—C16179.0 (4)
O1—C7—C8—C9178.2 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10A···O20.982.353.028 (6)126
C13—H13A···O2i0.932.493.312 (6)147
Symmetry code: (i) x, y, z+1.

Experimental details

Crystal data
Chemical formulaC17H12Br2N2O3
Mr452.11
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)11.9109 (3), 17.5018 (3), 8.5365 (2)
β (°) 94.960 (1)
V3)1772.87 (7)
Z4
Radiation typeMo Kα
µ (mm1)4.59
Crystal size (mm)0.30 × 0.20 × 0.04
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.341, 0.849
No. of measured, independent and
observed [I > 2σ(I)] reflections
23853, 4082, 1912
Rint0.068
(sin θ/λ)max1)0.652
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.104, 0.98
No. of reflections4082
No. of parameters217
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.48, 0.44

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

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10A···O20.98002.35003.028 (6)126.00
C13—H13A···O2i0.93002.49003.312 (6)147.00
Symmetry code: (i) x, y, z+1.
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

HKF and MH thank the Malaysian Government and Universiti Sains Malaysia for the Research University grant No. 1001/PFIZIK/811160. MH thanks Universiti Sains Malaysia for a post-doctoral research fellowship.

References

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