Crystal structure and Hirshfeld surface analysis of 1-(4-chloro­phen­yl)-2-{[5-(4-chloro­phen­yl)-1,3,4-oxa­diazol-2-yl]sulfan­yl}ethanone

Kumar, R.; Hussain, S.; Khan, K.M.; Perveen, S.; Yousuf, S.

doi:10.1107/S2056989017003978

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ISSN: 2056-9890

Volume 73| Part 4| April 2017| Pages 524-527

https://doi.org/10.1107/S2056989017003978

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Crystal structure and Hirshfeld surface analysis of 1-(4-chlorophenyl)-2-{[5-(4-chlorophenyl)-1,3,4-oxadiazol-2-yl]sulfanyl}ethanone

Rajesh Kumar,^a Shafqat Hussain,^b Khalid M. Khan,^a Shahnaz Perveen ^c and Sammer Yousuf ^a ^*

^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

Edited by C. Rizzoli, Universita degli Studi di Parma, Italy (Received 2 March 2017; accepted 11 March 2017; online 17 March 2017)

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

Heterocyclic compounds are well known for their applications in agriculture (Jakobi et al., 1999 ) and for the synthesis of pharmaceuticals (Vitaku et al., 2014 ). The broad range of biological activities of heterocyclic compounds has always fascinated chemists and the literature reveals many approaches to synthesize and derivatize libraries of heterocyclic compounds (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.

2. 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.

Figure 1
The molecular structure of the title compound with displacement ellipsoids drawn at 30% probability level.

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 crystal structure may be determined by comparison with those found in similar related compounds. For instance, in the crystal structure 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 crystal structure 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 crystal structure is provided by π–π interactions involving the pyridyl and oxadiazole rings with centroid-to-centroid distances of 3.883 Å.

Table 1
Hydrogen-bond geometry (Å, °)

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) $[-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Figure 2
Partial crystal packing of the title compound showing the formation of a undulating ribbon parallel to the b axis through C—H⋯N hydrogen bonds (dashed lines).

4. Hirshfeld surface analysis

The Hirshfeld surface analysis (Spackman & Jayatilaka, 2009 ) of the crystal structure 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.

Figure 3
d_norm mapped on the Hirshfeld surface, visualizing the intermolecular contacts of the title compound. Dotted lines indicate hydrogen bonds.

Figure 4
Hirshfeld surface two-dimensional fingerprint plot for the title compound (a) showing the: (b) H⋯C, (c) H⋯H, (d) H⋯Cl, (e) H⋯S, (f) H⋯N and (g) H⋯O interactions. The outline of the full fingerprint plots is shown in gray. d_i (x axis) and d_e (y axis) are the closest internal and external distance (values in Å) from a given point on the Hirshfeld surface contacts.

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 refinement details are summarized in (Table 2). 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 U_iso(H) = 1.2U_eq(C).

Table 2
Experimental details

Crystal data
Chemical formula	C₁₆H₁₀Cl₂N₂O₂S
M_r	365.22
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	273
a, b, c (Å)	19.1513 (7), 11.1589 (4), 7.5071 (3)
β (°)	92.088 (1)
V (Å³)	1603.26 (10)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.55
Crystal size (mm)	0.47 × 0.39 × 0.11

Data collection
Diffractometer	Bruker SMART APEX CCD area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 2000 )
T_min, T_max	0.784, 0.945
No. of measured, independent and observed [I > 2σ(I)] reflections	11526, 3762, 3058
R_int	0.022
(sin θ/λ)_max (Å⁻¹)	0.667

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.045, 0.132, 1.12
No. of reflections	3762
No. of parameters	208
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.34, −0.26
Computer programs: SMART and SAINT (Bruker, 2000), SHELXS97, SHELXL97 and SHELXTL (Sheldrick, 2008 ), PARST (Nardelli, 1995 ) and PLATON (Spek, 2009 ).

Supporting information

CCDC reference: 1537363

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S2056989017003978/rz5206sup1.cif

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

checkCIF report

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, PARST (Nardelli, 1995) and PLATON (Spek, 2009).

1-(4-Chlorophenyl)-2-{[5-(4-chlorophenyl)-1,3,4-oxadiazol-2-yl]sulfanyl}ethanone top

Crystal data top

C₁₆H₁₀Cl₂N₂O₂S	F(000) = 744
M_r = 365.22	D_x = 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

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	3762 independent reflections
Radiation source: fine-focus sealed tube	3058 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.022
ω scan	θ_max = 28.3°, θ_min = 1.1°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −25→25
T_min = 0.784, T_max = 0.945	k = −13→14
11526 measured reflections	l = −9→9

Refinement top

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(F_o²) + (0.069P)² + 0.2639P] where P = (F_o² + 2F_c²)/3
3762 reflections	(Δ/σ)_max < 0.001
208 parameters	Δρ_max = 0.34 e Å⁻³
0 restraints	Δρ_min = −0.26 e Å⁻³

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

	x	y	z	U_iso*/U_eq
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*

Atomic displacement parameters (Å²) top

	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)

Geometric parameters (Å, º) top

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)

Hydrogen-bond geometry (Å, º) top

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, Pakistan (award Nos. 20–1910, 20–2830).

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