research communications
and Hirshfeld surface analysis of 1-(4-chlorophenyl)-2-{[5-(4-chlorophenyl)-1,3,4-oxadiazol-2-yl]sulfanyl}ethanone
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, and cPCSIR Laboratories Complex, Karachi, Pakistan
*Correspondence e-mail: dr.sammer.yousuf@gmail.com
In the title compound, C16H10Cl2N2O2S, the dihedral angles formed by the chloro-substituted benzene rings with the central oxadiazole ring are 6.54 (9) and 6.94 (8)°. In the crystal, C—H⋯N hydrogen bonding links the molecules into undulating ribbons running parallel to the b axis. Hirshfeld surface analysis indicates that the most important contributions for the crystal packing are the H⋯C (18%), H⋯H (17%), H⋯Cl (16.6%), H⋯O (10.4%), H⋯N (8.9%) and H⋯S (5.9%) interactions.
Keywords: oxadizole; chlorophenyl; X-ray structure; Hirshfeld surface analysis; crystal structure.
CCDC reference: 1537363
1. Chemical context
et al., 1999) and for the synthesis of pharmaceuticals (Vitaku et al., 2014). The broad range of biological activities of has always fascinated chemists and the literature reveals many approaches to synthesize and derivatize libraries of (Khan et al., 2011; Chohan et al., 2006; Khan et al., 2005). The wide range of applications and biological activities of this class of compounds is due to the presence of heteroatoms (N, O, S) in the molecule (Kashtoh et al., 2014). Oxadiazoles are among the most widely studied moieties of organic chemistry due to their many important chemical and biological properties including antimycobacterial (Jha et al., 2009), antioxidant (Fadda et al., 2011), anticancer (Zhang et al., 2011), antitumor (Loetchutinat et al., 2003), antimicrobial (Şahin et al., 2002), antifungal (Zou et al., 2002), anti-inflammatory (Palaska et al., 2002) and hypotensive (Tyagi & Kumar, 2002) activities.
are well known for their applications in agriculture (Jakobi2. Structural commentary
The title compound (Fig. 1) is an oxadiazole derivative containing two chlorophenyl substituents attached to a central oxadiazole thioethanone unit. The C1–C6 and C11–C16 phenyl rings form dihedral angles of 6.54 (9) and 6.94 (8)°, respectively, with the oxadiazole ring. The dihedral angle between the oxadiazole ring and the mean plane through the S1/O1/C7–C8 fragment is 10.75 (8)°. Bond lengths and angles are not unusual.
3. Supramolecular features
In the crystal, molecules are connected by C—H⋯N hydrogen interactions, forming undulating ribbons parallel to the b axis (Table 1, Fig. 2). The importance of these interactions in stabilizing the may be determined by comparison with those found in similar related compounds. For instance, in the of 2-{5-[(1H-1,2,4-triazol-1-yl)methyl]-1,3,4-oxadiazol-2-ylthio}-1-(2,4-dichlorophenyl)ethanone (Xu et al., 2005) molecules are linked into chains via C—H⋯N hydrogen bonds having H⋯N separations of 2.48 Å. and C—H⋯C interactions having H⋯N distances of 2.41 Å. Similarly, in the of 1,3-bis{[5-(pyridin-2-yl)-1,3,4-oxadiazol-2-yl]sulfanyl}propan-2-one (Xia et al., 2011), two oxadiazole rings are present and form intermolecular hydrogen bonds of the type C—H⋯N with distances of 2.51 and 2.54 Å, respectively. Moreover, in the structure of the latter compound, further stabilization of the is provided by π–π interactions involving the pyridyl and oxadiazole rings with centroid-to-centroid distances of 3.883 Å.
4. Hirshfeld surface analysis
The Hirshfeld surface analysis (Spackman & Jayatilaka, 2009) of the suggests that the contribution to the crystal packing of the H⋯N interaction is 8.9% (Fig. 3). Other important interactions based upon the percentages are H⋯H (17%), H⋯O (10.4%), H⋯C (18%), H⋯S (5.9%) and H⋯Cl (16.6%). These interactions, however, were not found to be involved in hydrogen bonding, as observed for the H⋯N contribution (Fig. 4). The Hirshfeld surface diagram shows the location of atoms with the potential to form hydrogen bonds. These interactions are represented in two-dimensional fingerprint plots (Fig. 4), in which the cyan dots indicate the percentage of the interaction over the total Hirshfeld surface.
5. Synthesis and crystallization
The title compound was synthesized by the procdure reported by Kashtoh et al. (2014). 4-Chloro-1,3,4-oxadiazole-2-thiol (212 mg,1 mmol) and triethyl amine (0.1 mL) were taken in ethanol (10 mL) and stirred for 10 min. 2-Bromo-4′-chloroacetophenone (232 mg, 1 mmol) was then added slowly into the mixture and refluxed, while progress of the reaction was monitored by TLC. After completion of the reaction, the precipitate was filtered and washed with ethanol. The precipitate was crystallized from methanol to give the title compound in 344 mg, 94% yield.
6. Refinement
Crystal data, data collection and structure ). H atoms were located in a difference-Fourier map, but were positioned with idealized geometry and refined with C—H = 0.93–0.97 Å, and with Uiso(H) = 1.2Ueq(C).
details are summarized in (Table 2Supporting information
CCDC reference: 1537363
https://doi.org/10.1107/S2056989017003978/rz5206sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989017003978/rz5206Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989017003978/rz5206Isup3.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, PARST (Nardelli, 1995) and PLATON (Spek, 2009).C16H10Cl2N2O2S | F(000) = 744 |
Mr = 365.22 | Dx = 1.513 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 19.1513 (7) Å | Cell parameters from 3559 reflections |
b = 11.1589 (4) Å | θ = 3.2–27.7° |
c = 7.5071 (3) Å | µ = 0.55 mm−1 |
β = 92.088 (1)° | T = 273 K |
V = 1603.26 (10) Å3 | Block, colorless |
Z = 4 | 0.47 × 0.39 × 0.11 mm |
Bruker SMART APEX CCD area-detector diffractometer | 3762 independent reflections |
Radiation source: fine-focus sealed tube | 3058 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.022 |
ω scan | θmax = 28.3°, θmin = 1.1° |
Absorption correction: multi-scan (SADABS; Bruker, 2000) | h = −25→25 |
Tmin = 0.784, Tmax = 0.945 | k = −13→14 |
11526 measured reflections | l = −9→9 |
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)] = 0.045 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.132 | H-atom parameters constrained |
S = 1.12 | w = 1/[σ2(Fo2) + (0.069P)2 + 0.2639P] where P = (Fo2 + 2Fc2)/3 |
3762 reflections | (Δ/σ)max < 0.001 |
208 parameters | Δρmax = 0.34 e Å−3 |
0 restraints | Δρmin = −0.26 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 | ||
Cl1 | −0.31166 (3) | 0.71345 (7) | 0.43607 (10) | 0.0711 (2) | |
Cl2 | 0.54160 (4) | 0.62796 (12) | −0.30547 (16) | 0.1258 (4) | |
S1 | 0.09911 (2) | 0.52100 (4) | 0.14177 (7) | 0.04411 (16) | |
O1 | −0.01151 (8) | 0.43467 (13) | 0.3026 (2) | 0.0556 (4) | |
O2 | 0.21861 (7) | 0.57741 (12) | 0.00900 (19) | 0.0427 (3) | |
N1 | 0.14210 (9) | 0.72473 (14) | −0.0287 (2) | 0.0457 (4) | |
N2 | 0.20649 (9) | 0.75906 (16) | −0.1028 (3) | 0.0508 (4) | |
C1 | −0.14356 (11) | 0.50990 (18) | 0.3877 (3) | 0.0448 (5) | |
H1B | −0.1303 | 0.4313 | 0.4130 | 0.054* | |
C2 | −0.20957 (11) | 0.54753 (19) | 0.4258 (3) | 0.0494 (5) | |
H2B | −0.2410 | 0.4953 | 0.4766 | 0.059* | |
C3 | −0.22851 (10) | 0.6646 (2) | 0.3873 (3) | 0.0463 (5) | |
C4 | −0.18228 (10) | 0.74359 (19) | 0.3131 (3) | 0.0471 (5) | |
H4A | −0.1958 | 0.8222 | 0.2889 | 0.057* | |
C5 | −0.11620 (10) | 0.70548 (17) | 0.2752 (3) | 0.0428 (4) | |
H5A | −0.0849 | 0.7583 | 0.2250 | 0.051* | |
C6 | −0.09600 (9) | 0.58753 (16) | 0.3118 (3) | 0.0375 (4) | |
C7 | −0.02636 (10) | 0.53891 (16) | 0.2705 (3) | 0.0394 (4) | |
C8 | 0.02691 (9) | 0.61879 (16) | 0.1858 (3) | 0.0410 (4) | |
H8A | 0.0415 | 0.6828 | 0.2663 | 0.049* | |
H8B | 0.0079 | 0.6537 | 0.0761 | 0.049* | |
C9 | 0.15279 (9) | 0.61954 (16) | 0.0337 (3) | 0.0385 (4) | |
C10 | 0.24856 (10) | 0.67088 (18) | −0.0775 (3) | 0.0419 (4) | |
C11 | 0.32086 (10) | 0.6589 (2) | −0.1300 (3) | 0.0466 (5) | |
C12 | 0.35671 (13) | 0.7597 (2) | −0.1857 (3) | 0.0611 (6) | |
H12A | 0.3347 | 0.8340 | −0.1876 | 0.073* | |
C13 | 0.42443 (14) | 0.7499 (3) | −0.2380 (4) | 0.0743 (8) | |
H13A | 0.4485 | 0.8174 | −0.2747 | 0.089* | |
C14 | 0.45624 (12) | 0.6400 (3) | −0.2356 (4) | 0.0760 (8) | |
C15 | 0.42210 (13) | 0.5394 (3) | −0.1805 (5) | 0.0819 (9) | |
H15A | 0.4444 | 0.4654 | −0.1793 | 0.098* | |
C16 | 0.35398 (12) | 0.5494 (2) | −0.1265 (4) | 0.0643 (7) | |
H16A | 0.3305 | 0.4818 | −0.0877 | 0.077* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0415 (3) | 0.0839 (5) | 0.0889 (5) | 0.0064 (3) | 0.0182 (3) | −0.0073 (3) |
Cl2 | 0.0440 (4) | 0.1827 (11) | 0.1531 (10) | −0.0066 (5) | 0.0351 (5) | 0.0047 (8) |
S1 | 0.0393 (3) | 0.0369 (3) | 0.0567 (4) | 0.00321 (18) | 0.0088 (2) | 0.0004 (2) |
O1 | 0.0519 (8) | 0.0395 (8) | 0.0761 (11) | 0.0055 (6) | 0.0118 (7) | 0.0083 (7) |
O2 | 0.0347 (6) | 0.0408 (7) | 0.0531 (9) | 0.0030 (5) | 0.0068 (6) | 0.0007 (6) |
N1 | 0.0402 (8) | 0.0399 (9) | 0.0575 (11) | 0.0064 (7) | 0.0061 (7) | 0.0015 (7) |
N2 | 0.0464 (9) | 0.0448 (9) | 0.0615 (12) | 0.0013 (8) | 0.0073 (8) | 0.0058 (8) |
C1 | 0.0474 (11) | 0.0396 (10) | 0.0477 (12) | −0.0031 (8) | 0.0055 (9) | 0.0040 (8) |
C2 | 0.0458 (11) | 0.0505 (12) | 0.0527 (13) | −0.0098 (9) | 0.0122 (9) | 0.0030 (9) |
C3 | 0.0349 (9) | 0.0569 (12) | 0.0472 (12) | −0.0011 (8) | 0.0050 (8) | −0.0066 (9) |
C4 | 0.0446 (11) | 0.0421 (10) | 0.0550 (13) | 0.0043 (8) | 0.0053 (9) | −0.0002 (9) |
C5 | 0.0415 (10) | 0.0385 (10) | 0.0488 (12) | −0.0034 (7) | 0.0067 (8) | 0.0025 (8) |
C6 | 0.0376 (9) | 0.0369 (9) | 0.0380 (11) | −0.0020 (7) | 0.0025 (7) | −0.0035 (7) |
C7 | 0.0407 (9) | 0.0384 (10) | 0.0393 (11) | −0.0018 (7) | 0.0024 (8) | −0.0039 (7) |
C8 | 0.0349 (9) | 0.0374 (10) | 0.0511 (12) | −0.0001 (7) | 0.0062 (8) | −0.0050 (8) |
C9 | 0.0341 (9) | 0.0387 (9) | 0.0428 (11) | 0.0023 (7) | 0.0020 (7) | −0.0067 (8) |
C10 | 0.0387 (9) | 0.0428 (10) | 0.0441 (12) | −0.0009 (8) | 0.0022 (8) | −0.0023 (8) |
C11 | 0.0380 (10) | 0.0553 (12) | 0.0466 (12) | −0.0055 (8) | 0.0017 (8) | −0.0023 (9) |
C12 | 0.0542 (13) | 0.0643 (14) | 0.0652 (16) | −0.0073 (11) | 0.0064 (11) | 0.0097 (12) |
C13 | 0.0563 (15) | 0.094 (2) | 0.0731 (19) | −0.0240 (15) | 0.0099 (12) | 0.0140 (15) |
C14 | 0.0358 (11) | 0.115 (2) | 0.0776 (19) | −0.0088 (13) | 0.0123 (11) | −0.0057 (16) |
C15 | 0.0443 (13) | 0.0813 (19) | 0.121 (3) | 0.0050 (12) | 0.0181 (14) | −0.0089 (17) |
C16 | 0.0429 (11) | 0.0570 (13) | 0.0939 (19) | −0.0010 (10) | 0.0144 (12) | −0.0044 (13) |
Cl1—C3 | 1.735 (2) | C5—C6 | 1.396 (3) |
Cl2—C14 | 1.740 (2) | C5—H5A | 0.9300 |
S1—C9 | 1.7279 (19) | C6—C7 | 1.483 (2) |
S1—C8 | 1.8014 (18) | C7—C8 | 1.512 (2) |
O1—C7 | 1.219 (2) | C8—H8A | 0.9700 |
O2—C9 | 1.364 (2) | C8—H8B | 0.9700 |
O2—C10 | 1.366 (2) | C10—C11 | 1.459 (3) |
N1—C9 | 1.277 (2) | C11—C16 | 1.376 (3) |
N1—N2 | 1.424 (2) | C11—C12 | 1.390 (3) |
N2—C10 | 1.281 (3) | C12—C13 | 1.373 (3) |
C1—C2 | 1.372 (3) | C12—H12A | 0.9300 |
C1—C6 | 1.394 (3) | C13—C14 | 1.369 (4) |
C1—H1B | 0.9300 | C13—H13A | 0.9300 |
C2—C3 | 1.384 (3) | C14—C15 | 1.370 (4) |
C2—H2B | 0.9300 | C15—C16 | 1.385 (3) |
C3—C4 | 1.381 (3) | C15—H15A | 0.9300 |
C4—C5 | 1.375 (3) | C16—H16A | 0.9300 |
C4—H4A | 0.9300 | ||
C9—S1—C8 | 100.05 (9) | C7—C8—H8B | 110.8 |
C9—O2—C10 | 101.97 (14) | S1—C8—H8B | 110.8 |
C9—N1—N2 | 105.12 (15) | H8A—C8—H8B | 108.9 |
C10—N2—N1 | 106.51 (16) | N1—C9—O2 | 113.80 (16) |
C2—C1—C6 | 121.04 (18) | N1—C9—S1 | 131.81 (14) |
C2—C1—H1B | 119.5 | O2—C9—S1 | 114.39 (13) |
C6—C1—H1B | 119.5 | N2—C10—O2 | 112.59 (17) |
C1—C2—C3 | 118.81 (18) | N2—C10—C11 | 128.91 (19) |
C1—C2—H2B | 120.6 | O2—C10—C11 | 118.50 (17) |
C3—C2—H2B | 120.6 | C16—C11—C12 | 119.5 (2) |
C4—C3—C2 | 121.32 (18) | C16—C11—C10 | 121.17 (19) |
C4—C3—Cl1 | 119.47 (17) | C12—C11—C10 | 119.4 (2) |
C2—C3—Cl1 | 119.20 (16) | C13—C12—C11 | 120.2 (3) |
C5—C4—C3 | 119.66 (19) | C13—C12—H12A | 119.9 |
C5—C4—H4A | 120.2 | C11—C12—H12A | 119.9 |
C3—C4—H4A | 120.2 | C14—C13—C12 | 119.5 (2) |
C4—C5—C6 | 120.09 (18) | C14—C13—H13A | 120.3 |
C4—C5—H5A | 120.0 | C12—C13—H13A | 120.3 |
C6—C5—H5A | 120.0 | C13—C14—C15 | 121.4 (2) |
C1—C6—C5 | 119.08 (17) | C13—C14—Cl2 | 119.2 (2) |
C1—C6—C7 | 117.65 (17) | C15—C14—Cl2 | 119.4 (2) |
C5—C6—C7 | 123.26 (17) | C14—C15—C16 | 119.2 (3) |
O1—C7—C6 | 120.85 (17) | C14—C15—H15A | 120.4 |
O1—C7—C8 | 119.29 (17) | C16—C15—H15A | 120.4 |
C6—C7—C8 | 119.85 (16) | C11—C16—C15 | 120.3 (2) |
C7—C8—S1 | 104.72 (12) | C11—C16—H16A | 119.9 |
C7—C8—H8A | 110.8 | C15—C16—H16A | 119.9 |
S1—C8—H8A | 110.8 | ||
C9—N1—N2—C10 | 0.2 (2) | C10—O2—C9—S1 | 179.80 (13) |
C6—C1—C2—C3 | 0.1 (3) | C8—S1—C9—N1 | −11.3 (2) |
C1—C2—C3—C4 | −0.5 (3) | C8—S1—C9—O2 | 169.15 (14) |
C1—C2—C3—Cl1 | −179.61 (17) | N1—N2—C10—O2 | −0.1 (2) |
C2—C3—C4—C5 | 0.5 (3) | N1—N2—C10—C11 | 179.0 (2) |
Cl1—C3—C4—C5 | 179.62 (16) | C9—O2—C10—N2 | 0.0 (2) |
C3—C4—C5—C6 | −0.1 (3) | C9—O2—C10—C11 | −179.28 (17) |
C2—C1—C6—C5 | 0.3 (3) | N2—C10—C11—C16 | −166.0 (2) |
C2—C1—C6—C7 | −178.44 (19) | O2—C10—C11—C16 | 13.1 (3) |
C4—C5—C6—C1 | −0.3 (3) | N2—C10—C11—C12 | 13.5 (4) |
C4—C5—C6—C7 | 178.38 (18) | O2—C10—C11—C12 | −167.4 (2) |
C1—C6—C7—O1 | −0.2 (3) | C16—C11—C12—C13 | 0.5 (4) |
C5—C6—C7—O1 | −178.9 (2) | C10—C11—C12—C13 | −179.1 (2) |
C1—C6—C7—C8 | 179.18 (17) | C11—C12—C13—C14 | 0.3 (4) |
C5—C6—C7—C8 | 0.5 (3) | C12—C13—C14—C15 | −0.6 (5) |
O1—C7—C8—S1 | 4.4 (2) | C12—C13—C14—Cl2 | 179.0 (2) |
C6—C7—C8—S1 | −174.98 (14) | C13—C14—C15—C16 | 0.1 (5) |
C9—S1—C8—C7 | 176.28 (13) | Cl2—C14—C15—C16 | −179.4 (2) |
N2—N1—C9—O2 | −0.2 (2) | C12—C11—C16—C15 | −0.9 (4) |
N2—N1—C9—S1 | −179.78 (16) | C10—C11—C16—C15 | 178.6 (2) |
C10—O2—C9—N1 | 0.2 (2) | C14—C15—C16—C11 | 0.6 (5) |
D—H···A | D—H | H···A | D···A | D—H···A |
C1—H1B···N1i | 0.93 | 2.48 | 3.353 (3) | 157 |
Symmetry code: (i) −x, y−1/2, −z+1/2. |
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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