research communications
and Hirshfeld surface analysis of 1-(4-bromophenyl)-2-{[5-(pyridin-3-yl)-1,3,4-oxadiazol-2-yl]sulfanyl}ethan-1-one
aH. E. J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi-75270, Pakistan, bKarakoram International University, Gilgit, Pakistan, cPCSIR Laboratories Complex, Karachi, Pakistan, and dH. E. J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, Sahrah-e-Dr. Salimuzzaman Siddiqui, Karachi-75280, Pakistan
*Correspondence e-mail: dr.sammer.yousuf@gmail.com
In the title compound, C15H10BrN3O2S, the dihedral angles between the 1,3,4-oxadiazole ring and the 3-pyridinyl and bromobenzene rings are 12.17 (15) and 18.74 (15)°, respectively. In the crystal, the molecules are linked into [100] chains by way of C—H⋯O, C—H⋯N, C—H⋯S hydrogen bonds. The Hirshfeld surface analysis indicates that the most important contributions to the packing are H⋯H (19.5%), N⋯H (17.3%), C⋯H (15.5%), Br⋯H (11.7%), and O⋯H (11.0%) interactions.
CCDC reference: 1540579
1. Chemical context
Substituted 1,3,4-oxadiazoles exhibit numerous biological activities such as antibacterial and antifungal (Prakash et al., 2010, Chandrakantha et al., 2010), anticancer (Abu-Zaied et al., 2011), anti-inflammatory, analgesic (Husain et al., 2009, Omar et al., 1996), anticonvulsant and neurotoxic activities (Rajak et al., 2010, Zarghi et al., 2005). Chemical compounds having a 1,3,4-oxadiazole moiety are also important contributors towards the synthesis of biologically active having antibacterial activity against resistant strains (Bharti et al., 2010). As part of our studies in this area, we now describe the synthesis and structure of the title compound (I), a product of the condensation reaction between alcoholic solutions of 5-(3-pyridyl)-1,3,4-oxadiazole-2-thiol and 2,4-dibromoacetophenone in the presence triethyl amine (Kashtoh et al., 2014).
2. Structural commentary
The structure of (I) (Fig. 1) is composed of three near-planar aromatic rings [bromophenyl (A), 3-pyridinyl (B) and 1,3,4-oxadiazol (C)]. The inter-ring dihedral angles are A/B = 6.93 (15), A/C = 18.74 (15) and B/C = 12.17 (15)°. The C7—C8—S2—C9 torsion angle of 172.56 (17)° indicates approximate coplanarity of these atoms. Otherwise, geometrical data for (I) are similar to those found in structurally related compounds (Xia et al., 2011; Xu et al., 2005).
3. Hydrogen bonding and Hirshfeld surface analysis
The packing of (I) is consolidated by C1—H1B⋯O1, C1—H2B⋯S2 and C4—H4A⋯N2 hydrogen bonds, which form chains running along a-axis direction (Fig. 2, Table 1). The Hirshfeld surface analysis (Hirshfeld, 1977) of the indicates that the contribution of the H⋯H intermolecular interactions to the crystal packing amounts to 19.5%, N⋯H = 17.3%, Br⋯H = 11.7% and O⋯H = 11.0%. Minor intermolecular contacts for the cohesion of the structure are: C⋯O = 4.7%, C⋯C = 3.6% and others (Br⋯C, C⋯S, C⋯N, Br⋯S, N⋯N, Br⋯N, O⋯N)= 10.4%. These contacts are represented by conventional mapping of dnorm on the molecular Hirshfeld surface, as shown in Fig. 3. The H⋯H contribution to the crystal packing is shown as a Hirshfeld surface two-dimensional fingerprint plot with red dots (Wolff et al., 2012). The de (y axis) and di (x axis) values are the closest external and internal distances (Å) from given points on the Hirshfeld surface (Fig. 4).
4. Comparison with reported literature
A database search disclosed a long list of compounds containing the 1,3,4-oxadiazole moiety; however, only two examples of sulfanylethanone-substituted 1,3,4-oxadiazole derivatives were found, viz. 1,3-bis{[5-(pyridin-2-yl)-1,3,4-oxadiazol-2-yl]sulfanyl}propan-2-one (II) (Xia et al., 2011) and 2-{5-[(1H-1,2,4-triazol-1-yl)-methyl]-1,3,4-oxadiazol-2-ylthio}-1-(2,4-dichlorophenyl)ethanone (III) (Xu et al., 2005). H⋯N interactions were found to be the most relevant intermolecular interactions to form hydrogen bonds with neighboring molecules. Therefore, D—H⋯N interactions were considered in a comparison with reported structures. In the crystal of (II), the molecules are linked into a three-dimensional network via weak C—H⋯N hydrogen bonds (H⋯N distances = 2.51 and 2.54 Å) In (III), the C—H⋯N hydrogen bonds are found to be slightly weaker in comparison with the first structure (H⋯N distances = 2.41 Å). The change in substituents also changes the packing pattern towards zigzag chains extending along the b-axis direction. In addition, both (II) and (III) feature aromatic π–π stacking interactions, which are not observed in (I).
5. Synthesis and crystallization
5-(3-Pyridyl)-1,3,4-oxadiazole-2-thiol (179 mg, 1 mmol) and triethyl amine (0.1 ml) were added in ethanol (10 ml) and stirred for 10 min in a round-bottomed flask. After 10 min, to the reaction mixture was slowly added 2 4-dibromacetophenone (278 mg, 1 mmol). The mixture was refluxed until complete consumption of starting materials, the progress of reaction being monitored by TLC. After 2 h, the precipitate that had formed was separated, washed with ethanol and recrystallized from methanol solution to afford colourless blocks (346 mg, 92% yield).
6. Refinement
Crystal data, data collection and structure . H atoms were positioned geometrically with C—H = 0.93 Å (CH) or 0.97 Å (CH2) and constrained to ride on their parent atoms with Uiso(H)= 1.2Ueq(C).
details are summarized in Table 2Supporting information
CCDC reference: 1540579
https://doi.org/10.1107/S2056989017004819/hb7660sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989017004819/hb7660Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989017004819/hb7660Isup3.cml
Data collection: SMART (Bruker, 2000); cell
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).C15H10BrN3O2S | Dx = 1.648 Mg m−3 |
Mr = 376.23 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, Pbca | Cell parameters from 3887 reflections |
a = 11.9144 (16) Å | θ = 2.7–22.9° |
b = 8.3755 (12) Å | µ = 2.86 mm−1 |
c = 30.382 (4) Å | T = 273 K |
V = 3031.8 (7) Å3 | Block, colorless |
Z = 8 | 0.47 × 0.39 × 0.11 mm |
F(000) = 1504 |
Bruker SMART APEX CCD diffractometer | 2765 independent reflections |
Radiation source: fine-focus sealed tube | 2106 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.038 |
ω scan | θmax = 25.5°, θmin = 1.3° |
Absorption correction: multi-scan (SADABS; Bruker, 2000) | h = −14→13 |
Tmin = 0.347, Tmax = 0.746 | k = −10→10 |
16806 measured reflections | l = −36→36 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.035 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.114 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.13 | w = 1/[σ2(Fo2) + (0.0639P)2 + 0.238P] where P = (Fo2 + 2Fc2)/3 |
2765 reflections | (Δ/σ)max = 0.002 |
199 parameters | Δρmax = 0.40 e Å−3 |
0 restraints | Δρmin = −0.25 e Å−3 |
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. |
x | y | z | Uiso*/Ueq | ||
Br1 | 0.32966 (4) | 1.17413 (5) | 0.651655 (12) | 0.0855 (2) | |
S2 | 0.48889 (6) | 0.57198 (9) | 0.42780 (3) | 0.0573 (2) | |
O1 | 0.58756 (16) | 0.7313 (2) | 0.49352 (7) | 0.0627 (6) | |
O2 | 0.42221 (15) | 0.3878 (2) | 0.36429 (6) | 0.0519 (5) | |
N1 | 0.2823 (2) | 0.4393 (3) | 0.40960 (8) | 0.0593 (6) | |
N2 | 0.2436 (2) | 0.3373 (3) | 0.37529 (9) | 0.0632 (7) | |
N3 | 0.4463 (3) | 0.0865 (4) | 0.25578 (10) | 0.0847 (9) | |
C1 | 0.3327 (2) | 0.8827 (4) | 0.54232 (11) | 0.0561 (7) | |
H1B | 0.2798 | 0.8391 | 0.5233 | 0.067* | |
C2 | 0.2986 (3) | 0.9787 (4) | 0.57656 (11) | 0.0642 (8) | |
H2B | 0.2227 | 1.0005 | 0.5806 | 0.077* | |
C3 | 0.3762 (3) | 1.0418 (3) | 0.60463 (9) | 0.0561 (7) | |
C4 | 0.4894 (2) | 1.0117 (3) | 0.59921 (10) | 0.0572 (8) | |
H4A | 0.5416 | 1.0550 | 0.6186 | 0.069* | |
C5 | 0.5238 (2) | 0.9178 (3) | 0.56513 (10) | 0.0528 (7) | |
H5A | 0.5999 | 0.8979 | 0.5612 | 0.063* | |
C6 | 0.4458 (2) | 0.8510 (3) | 0.53610 (9) | 0.0450 (6) | |
C7 | 0.4875 (2) | 0.7497 (3) | 0.49968 (9) | 0.0468 (6) | |
C8 | 0.4052 (2) | 0.6676 (3) | 0.46970 (10) | 0.0495 (7) | |
H8A | 0.3543 | 0.7445 | 0.4566 | 0.059* | |
H8B | 0.3617 | 0.5892 | 0.4858 | 0.059* | |
C9 | 0.3863 (2) | 0.4642 (3) | 0.40109 (9) | 0.0501 (7) | |
C10 | 0.3272 (2) | 0.3106 (3) | 0.35029 (10) | 0.0514 (7) | |
C11 | 0.3335 (2) | 0.2139 (3) | 0.31076 (11) | 0.0541 (7) | |
C12 | 0.2370 (3) | 0.1585 (3) | 0.29051 (11) | 0.0621 (8) | |
H12A | 0.1665 | 0.1820 | 0.3020 | 0.075* | |
C13 | 0.2476 (3) | 0.0681 (4) | 0.25307 (11) | 0.0717 (10) | |
H13A | 0.1842 | 0.0287 | 0.2389 | 0.086* | |
C14 | 0.3520 (3) | 0.0365 (4) | 0.23684 (12) | 0.0779 (10) | |
H14A | 0.3575 | −0.0232 | 0.2111 | 0.093* | |
C15 | 0.4355 (3) | 0.1747 (4) | 0.29175 (12) | 0.0702 (9) | |
H15A | 0.5005 | 0.2127 | 0.3051 | 0.084* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br1 | 0.1083 (4) | 0.0886 (3) | 0.0597 (3) | −0.00727 (19) | 0.02208 (18) | −0.00144 (17) |
S2 | 0.0409 (4) | 0.0600 (4) | 0.0711 (5) | −0.0033 (3) | 0.0054 (3) | −0.0031 (4) |
O1 | 0.0357 (14) | 0.0716 (13) | 0.0808 (15) | 0.0013 (10) | −0.0025 (10) | 0.0025 (11) |
O2 | 0.0407 (11) | 0.0572 (10) | 0.0578 (12) | −0.0024 (9) | 0.0065 (9) | 0.0010 (9) |
N1 | 0.0405 (14) | 0.0658 (15) | 0.0716 (17) | −0.0039 (11) | 0.0083 (12) | −0.0052 (12) |
N2 | 0.0454 (16) | 0.0682 (16) | 0.0759 (18) | −0.0064 (11) | 0.0074 (14) | −0.0062 (13) |
N3 | 0.075 (2) | 0.103 (2) | 0.076 (2) | 0.0034 (17) | 0.0039 (16) | −0.0197 (17) |
C1 | 0.0354 (17) | 0.0653 (17) | 0.068 (2) | −0.0096 (13) | −0.0067 (13) | 0.0019 (15) |
C2 | 0.0432 (18) | 0.075 (2) | 0.074 (2) | −0.0041 (15) | 0.0102 (15) | 0.0014 (17) |
C3 | 0.059 (2) | 0.0566 (16) | 0.0527 (17) | −0.0062 (14) | 0.0036 (14) | 0.0095 (13) |
C4 | 0.055 (2) | 0.0570 (17) | 0.0592 (19) | −0.0102 (13) | −0.0151 (14) | 0.0116 (14) |
C5 | 0.0409 (16) | 0.0536 (16) | 0.0638 (18) | −0.0013 (12) | −0.0102 (13) | 0.0114 (14) |
C6 | 0.0343 (15) | 0.0450 (13) | 0.0558 (16) | −0.0031 (11) | −0.0059 (12) | 0.0128 (12) |
C7 | 0.0350 (18) | 0.0455 (14) | 0.0600 (17) | −0.0014 (11) | −0.0046 (12) | 0.0130 (12) |
C8 | 0.0381 (16) | 0.0504 (15) | 0.0601 (17) | −0.0002 (11) | 0.0001 (12) | 0.0039 (12) |
C9 | 0.0451 (18) | 0.0450 (14) | 0.0600 (18) | 0.0018 (12) | 0.0039 (13) | 0.0057 (13) |
C10 | 0.0409 (18) | 0.0515 (16) | 0.0619 (19) | −0.0025 (12) | 0.0015 (13) | 0.0096 (13) |
C11 | 0.053 (2) | 0.0515 (15) | 0.0580 (18) | 0.0001 (12) | −0.0009 (13) | 0.0075 (13) |
C12 | 0.053 (2) | 0.0605 (18) | 0.073 (2) | −0.0053 (14) | −0.0073 (16) | 0.0071 (15) |
C13 | 0.074 (3) | 0.069 (2) | 0.072 (2) | −0.0099 (18) | −0.0188 (18) | −0.0001 (17) |
C14 | 0.085 (3) | 0.079 (2) | 0.070 (2) | 0.002 (2) | −0.010 (2) | −0.0093 (18) |
C15 | 0.055 (2) | 0.087 (2) | 0.069 (2) | −0.0046 (16) | 0.0017 (16) | −0.0092 (17) |
Br1—C3 | 1.891 (3) | C4—C5 | 1.363 (4) |
S2—C9 | 1.722 (3) | C4—H4A | 0.9300 |
S2—C8 | 1.804 (3) | C5—C6 | 1.398 (4) |
O1—C7 | 1.217 (3) | C5—H5A | 0.9300 |
O2—C9 | 1.357 (3) | C6—C7 | 1.480 (4) |
O2—C10 | 1.372 (3) | C7—C8 | 1.504 (4) |
N1—C9 | 1.283 (4) | C8—H8A | 0.9700 |
N1—N2 | 1.424 (3) | C8—H8B | 0.9700 |
N2—C10 | 1.272 (4) | C10—C11 | 1.451 (4) |
N3—C15 | 1.326 (4) | C11—C12 | 1.384 (4) |
N3—C14 | 1.330 (5) | C11—C15 | 1.385 (4) |
C1—C2 | 1.376 (4) | C12—C13 | 1.372 (4) |
C1—C6 | 1.387 (4) | C12—H12A | 0.9300 |
C1—H1B | 0.9300 | C13—C14 | 1.364 (4) |
C2—C3 | 1.365 (4) | C13—H13A | 0.9300 |
C2—H2B | 0.9300 | C14—H14A | 0.9300 |
C3—C4 | 1.382 (4) | C15—H15A | 0.9300 |
C9—S2—C8 | 99.97 (13) | C7—C8—H8A | 110.6 |
C9—O2—C10 | 102.6 (2) | S2—C8—H8A | 110.6 |
C9—N1—N2 | 105.2 (2) | C7—C8—H8B | 110.6 |
C10—N2—N1 | 106.8 (2) | S2—C8—H8B | 110.6 |
C15—N3—C14 | 116.7 (3) | H8A—C8—H8B | 108.7 |
C2—C1—C6 | 120.1 (3) | N1—C9—O2 | 113.2 (2) |
C2—C1—H1B | 119.9 | N1—C9—S2 | 132.5 (2) |
C6—C1—H1B | 119.9 | O2—C9—S2 | 114.32 (19) |
C3—C2—C1 | 119.9 (3) | N2—C10—O2 | 112.2 (3) |
C3—C2—H2B | 120.0 | N2—C10—C11 | 129.3 (3) |
C1—C2—H2B | 120.0 | O2—C10—C11 | 118.5 (2) |
C2—C3—C4 | 121.1 (3) | C12—C11—C15 | 117.7 (3) |
C2—C3—Br1 | 120.0 (2) | C12—C11—C10 | 120.8 (3) |
C4—C3—Br1 | 118.9 (2) | C15—C11—C10 | 121.5 (3) |
C5—C4—C3 | 119.2 (3) | C13—C12—C11 | 118.5 (3) |
C5—C4—H4A | 120.4 | C13—C12—H12A | 120.8 |
C3—C4—H4A | 120.4 | C11—C12—H12A | 120.8 |
C4—C5—C6 | 120.7 (3) | C14—C13—C12 | 119.4 (3) |
C4—C5—H5A | 119.6 | C14—C13—H13A | 120.3 |
C6—C5—H5A | 119.6 | C12—C13—H13A | 120.3 |
C1—C6—C5 | 118.9 (3) | N3—C14—C13 | 123.6 (4) |
C1—C6—C7 | 122.5 (3) | N3—C14—H14A | 118.2 |
C5—C6—C7 | 118.6 (2) | C13—C14—H14A | 118.2 |
O1—C7—C6 | 121.1 (2) | N3—C15—C11 | 124.1 (3) |
O1—C7—C8 | 119.2 (3) | N3—C15—H15A | 117.9 |
C6—C7—C8 | 119.7 (2) | C11—C15—H15A | 117.9 |
C7—C8—S2 | 105.69 (19) | ||
C9—N1—N2—C10 | 0.6 (3) | C10—O2—C9—N1 | 0.1 (3) |
C6—C1—C2—C3 | −0.5 (5) | C10—O2—C9—S2 | 178.86 (18) |
C1—C2—C3—C4 | 0.3 (5) | C8—S2—C9—N1 | −7.1 (3) |
C1—C2—C3—Br1 | 179.8 (2) | C8—S2—C9—O2 | 174.34 (19) |
C2—C3—C4—C5 | 0.2 (4) | N1—N2—C10—O2 | −0.6 (3) |
Br1—C3—C4—C5 | −179.3 (2) | N1—N2—C10—C11 | 179.7 (3) |
C3—C4—C5—C6 | −0.6 (4) | C9—O2—C10—N2 | 0.3 (3) |
C2—C1—C6—C5 | 0.1 (4) | C9—O2—C10—C11 | −179.9 (2) |
C2—C1—C6—C7 | −179.5 (3) | N2—C10—C11—C12 | 12.1 (5) |
C4—C5—C6—C1 | 0.5 (4) | O2—C10—C11—C12 | −167.6 (2) |
C4—C5—C6—C7 | −179.9 (2) | N2—C10—C11—C15 | −168.4 (3) |
C1—C6—C7—O1 | 175.7 (3) | O2—C10—C11—C15 | 11.9 (4) |
C5—C6—C7—O1 | −3.8 (4) | C15—C11—C12—C13 | 0.2 (4) |
C1—C6—C7—C8 | −4.4 (4) | C10—C11—C12—C13 | 179.7 (3) |
C5—C6—C7—C8 | 176.0 (2) | C11—C12—C13—C14 | −0.4 (5) |
O1—C7—C8—S2 | −4.8 (3) | C15—N3—C14—C13 | −1.6 (6) |
C6—C7—C8—S2 | 175.32 (19) | C12—C13—C14—N3 | 1.2 (6) |
C9—S2—C8—C7 | 172.56 (17) | C14—N3—C15—C11 | 1.4 (5) |
N2—N1—C9—O2 | −0.4 (3) | C12—C11—C15—N3 | −0.7 (5) |
N2—N1—C9—S2 | −178.9 (2) | C10—C11—C15—N3 | 179.8 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
C1—H1B···O1i | 0.93 | 2.42 | 3.260 (3) | 150 |
C2—H2B···S2i | 0.93 | 2.86 | 3.716 (3) | 153 |
C4—H4A···N2ii | 0.93 | 2.58 | 3.372 (4) | 144 |
Symmetry codes: (i) x−1/2, −y+3/2, −z+1; (ii) x+1/2, −y+3/2, −z+1. |
Acknowledgements
The authors are thankful to the financial support of Higher Education Commission (HEC) Pakistan through research projects No. 20–1910 and 20–2830.
Funding information
Funding for this research was provided by: Higher Education Commission, Pakistanhttps://doi.org/10.13039/501100004681 (award Nos. 20–1910, 20–2830).
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