5-(2-Chloro­phen­yl)-3-(2H-chromen-3-yl)-1,2,4-oxa­diazole

Baral, N.; Nayak, S.; Pal, S.; Mohapatra, S.

doi:10.1107/S2414314618001293

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 3| Part 1| January 2018| x180129

https://doi.org/10.1107/S2414314618001293

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access

5-(2-Chlorophenyl)-3-(2H-chromen-3-yl)-1,2,4-oxadiazole

Nilofar Baral,^a Sabita Nayak,^a Satyanarayan Pal ^b ^* and Seetaram Mohapatra ^a

^aDepartment of Chemistry, Ravenshaw University, Cuttack, Odisha, India, and ^bP.G. Department of Chemistry, Utkal University, Bhubaneswar, Odisha, India
^*Correspondence e-mail: snpal75@gmail.com

Edited by J. Simpson, University of Otago, New Zealand (Received 17 January 2018; accepted 20 January 2018; online 26 January 2018)

In the title compound, C₁₇H₁₁ClN₂O₂, the central oxadiazole ring carries 2H-chromene and 2-chlorophenyl substituents at the 3- and 5-positions, respectively. C—H⋯O and C—H⋯Cl hydrogen bonds form two-dimensional sheets parallel to (212), with each individual molecule involved in six of these weak interactions. The sheets are stacked perpendicular to (212) by offset π–π stacking interactions.

Keywords: crystal structure; C—H⋯Cl and C—H⋯O hydrogen bonding; two-dimensional sheet structure; π–π interactions.

CCDC reference: 1818314

Structure description

Oxadiazole derivatives have attracted considerable interest due to their unique chemical structures and wide variety of biological applications. These include use as antitumour (Maftei et al., 2013 ), antifungal, antibacterial and anti-inflammatory agents (Rakesh et al., 2009 ). Chromene (benzopyran) is also an important medicinal pharmacophore. It is an integral part of many natural alkaloids and flavonoids and is known to possess biological activities similar to the oxadiazoles, together with antivascular, antimicrobial and antioxidant properties (Gourdeau et al., 2004 ). Another important feature is its lipophilic nature which helps it to pass readily through cell membranes. We are interested in the design and synthesis of chromene-based oxadiazole derivatives and studies of their biological activity, and we report here the structure of the chromene–oxadiazole derivative 5-(2-chlorophenyl)-3-(2H-chromen-3-yl)-1,2,4-oxadiazole.

A perspective view of the molecule is shown in Fig. 1. The molecule is not completely planar. The plane of the central oxadiazole ring is inclined at 1.2 (1)° to the plane of the 2-chlorophenyl ring and 12.24 (9)° to the best-fit plane of the chromene ring system. The C—Cl distance [1.7221 (17) Å] is consistent with the reported values (Hathwar et al., 2010 ). The bond lengths and angles of the chromene and oxadiazole units are also similar to those reported in the literature (Devarajegowda et al., 2015 ; Du & Zhao, 2004 ). In the crystal, weak intermolecular C—H⋯Cl and C—H⋯O interactions (Desiraju et al., 1999 ) are found. C14—H14⋯Cl1 hydrogen bonds form inversion dimers enclosing R₂²(24) rings, while a second inversion dimer forms through C5—H5⋯O1 contacts with an R₂²(10) ring motif (Bernstein et al., 1995 ). A C2—H2⋯O2 interaction completes the hydrogen-bonding network, forming sheets of molecules parallel to (212), with each individual molecule in the sheet bound to four others through six nonclassical hydrogen-bonding interactions (Table 1 and Fig. 2). Adjacent sheets are linked by inversion related offset π–π stacking interactions (Table 2 and Fig. 3), forming a three-dimensional network.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C5—H5⋯O1ⁱ	0.93	2.62	3.389 (2)	140
C14—H14⋯Cl1ⁱⁱ	0.93	2.94	3.625 (2)	132
C2—H2⋯O2ⁱⁱⁱ	0.93	2.67	3.550 (2)	158
Symmetry codes: (i) -x+1, -y+3, -z+2; (ii) -x+2, -y+1, -z+2; (iii) x-1, y, z+1.

Table 2
π–π interaction details (Å, °)

Cg1 and Cg2 are the centroids of the C7/N1/C8/N2/O2 and C11–C16 rings, respectively

Centroid (Cg)	Centroid (Cg)	Cg⋯Cg distance	Dihedral angle	Slippage distance
Cg1	Cg2ⁱ	3.9370 (11)	14.57 (10)	1.69
Cg2	Cg1ⁱ	3.9370 (11)	14.57 (10)	2.318
Symmetry code: (i) −x, −y, −z.

Figure 1
The molecular structure of the title compound, with displacement ellipsoids drawn at the 50% probability level.

Figure 2
A view of two-dimensional sheet structure formed from C—H⋯O and C—H⋯Cl hydrogen bonds (cyan dotted lines).

Figure 3
Packing of the title compound, showing the π–π interactions stacking adjacent molecular sheets (dark blue dotted lines show the π–π interactions and cyan dotted lines indicate hydrogen bonds).

Synthesis and crystallization

This compound was prepared by the treatment of N-hydroxy-2H-chromene-3-carboximidamide (1 equiv.) with 2-chlorobenzoic acid (0.8 equiv.) in the presence of ethylene dicarboimide (EDCI, 1.2 equiv) and N-hydroxybenzotriazole (HOBt, 1.2 equiv.) in dry DMF at 353 K for 6 h (Fig. 4). The reaction mixture was extracted with water and ethyl acetate. The pure compound was isolated by column chromatography, eluting with 2–5% ethyl acetate/hexane. The solvents were evaporated and dried to give the title compound in 75% yield (m.p. 478 K). Colourless rectangular crystals were obtained by slow evaporation of a solution of the compound in a dichloromethane/hexane mixture. ¹H NMR (400 MHz, CDCl₃): δ 8.01 (d, J = 8.0 Hz, 2H), 7.37–7.33 (m, 3H), 7.21–7.17 (m, 2H), 6.94 (t, J = 8.0 Hz, 1H), 6.89 (d, J = 8.0 Hz, 1H), 5.26 (s, 2H); ¹³C NMR (100 MHz, CDCl₃): δ 173.9, 166.0, 154.7, 134.8, 131.9, 131.6, 131.1, 128.6, 128.5, 128.4, 127.2, 126.8, 121.9, 121.4, 119.2, 116.2, 64.2.

Figure 4
The synthetic scheme for the title compound.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3.

Table 3
Experimental details

Crystal data
Chemical formula	C₁₇H₁₁ClN₂O₂
M_r	310.73
Crystal system, space group	Triclinic, P $[\overline{1}]$
Temperature (K)	296
a, b, c (Å)	8.7208 (4), 8.7703 (3), 9.6278 (4)
α, β, γ (°)	86.035 (3), 80.227 (3), 79.352 (2)
V (Å³)	712.65 (5)
Z	2
Radiation type	Mo Kα
μ (mm⁻¹)	0.28
Crystal size (mm)	0.40 × 0.28 × 0.20

Data collection
Diffractometer	Bruker APEXII
No. of measured, independent and observed [I > 2σ(I)] reflections	11000, 3518, 2452
R_int	0.028
(sin θ/λ)_max (Å⁻¹)	0.668

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.134, 1.11
No. of reflections	3518
No. of parameters	199
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.38, −0.26
Computer programs: APEX2 and SAINT (Bruker, 2014 ), SHELXT2014 (Sheldrick, 2015a ), SHELXL2014 (Sheldrick, 2015b ), ORTEP-3 for Windows and WinGX (Farrugia, 2012 ), Mercury (Macrae et al., 2008 ), publCIF (Westrip, 2010 ) and PLATON (Spek, 2009 ).

Structural data

CCDC reference: 1818314

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S2414314618001293/sj4155sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314618001293/sj4155Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX2 (Bruker 2014); cell refinement: SAINT (Bruker 2014; data reduction: SAINT (Bruker 2014); program(s) used to solve structure: SHELXT2014 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: WinGX (Farrugia, 2012), publCIF (Westrip, 2010) and PLATON (Spek 2009).

5-(2-Chlorophenyl)-3-(2H-chromen-3-yl)-1,2,4-oxadiazole top

Crystal data top

C₁₇H₁₁ClN₂O₂	Z = 2
M_r = 310.73	F(000) = 320
Triclinic, P1	D_x = 1.448 Mg m⁻³
a = 8.7208 (4) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.7703 (3) Å	Cell parameters from 2986 reflections
c = 9.6278 (4) Å	θ = 2.4–26.6°
α = 86.035 (3)°	µ = 0.28 mm⁻¹
β = 80.227 (3)°	T = 296 K
γ = 79.352 (2)°	Rectangular block, colourless
V = 712.65 (5) Å³	0.40 × 0.28 × 0.20 mm

Data collection top

Bruker APEXII diffractometer	R_int = 0.028
Radiation source: sealed tube	θ_max = 28.3°, θ_min = 2.2°
φ and ω scans	h = −11→11
11000 measured reflections	k = −11→11
3518 independent reflections	l = −12→12
2452 reflections with I > 2σ(I)

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.046	H-atom parameters constrained
wR(F²) = 0.134	w = 1/[σ²(F_o²) + (0.0629P)² + 0.0537P] where P = (F_o² + 2F_c²)/3
S = 1.11	(Δ/σ)_max < 0.001
3518 reflections	Δρ_max = 0.38 e Å⁻³
199 parameters	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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Cl1	0.52115 (6)	0.91781 (6)	1.30274 (6)	0.0650 (2)
O1	0.61910 (15)	1.27500 (14)	0.95744 (13)	0.0529 (3)
O2	1.09361 (16)	0.89357 (16)	0.61902 (13)	0.0601 (4)
N1	0.69651 (16)	1.03574 (15)	1.03518 (15)	0.0418 (3)
N2	0.75145 (19)	1.21176 (18)	0.86047 (16)	0.0536 (4)
C3	0.2109 (2)	1.3029 (2)	1.3854 (2)	0.0597 (5)
H3	0.1264	1.3352	1.4559	0.072*
C4	0.2528 (2)	1.4042 (2)	1.2754 (2)	0.0602 (5)
H4	0.1969	1.5052	1.2720	0.072*
C5	0.3759 (2)	1.3563 (2)	1.1718 (2)	0.0527 (5)
H5	0.4019	1.4259	1.0981	0.063*
C6	0.4649 (2)	1.20576 (19)	1.17225 (18)	0.0409 (4)
C7	0.5951 (2)	1.16306 (19)	1.05849 (18)	0.0401 (4)
C8	0.7906 (2)	1.07079 (19)	0.91245 (17)	0.0410 (4)
C9	0.9241 (2)	0.9627 (2)	0.84305 (17)	0.0408 (4)
C17	0.9677 (2)	0.81924 (19)	0.89577 (18)	0.0421 (4)
H17	0.9143	0.7866	0.9814	0.051*
C16	1.09781 (19)	0.71486 (19)	0.81982 (18)	0.0426 (4)
C11	1.1551 (2)	0.7555 (2)	0.6807 (2)	0.0492 (4)
C12	1.2678 (3)	0.6539 (3)	0.5981 (2)	0.0649 (6)
H12	1.3036	0.6817	0.5048	0.078*
C13	1.3268 (3)	0.5112 (3)	0.6547 (3)	0.0706 (6)
H13	1.4018	0.4422	0.5987	0.085*
C15	1.1619 (2)	0.5702 (2)	0.8749 (2)	0.0526 (5)
H15	1.1270	0.5414	0.9680	0.063*
C14	1.2766 (3)	0.4691 (2)	0.7928 (2)	0.0634 (6)
H14	1.3194	0.3734	0.8306	0.076*
C10	1.0205 (2)	1.0176 (2)	0.7108 (2)	0.0544 (5)
H10A	0.9526	1.0945	0.6607	0.065*
H10B	1.1017	1.0674	0.7362	0.065*
C1	0.4216 (2)	1.1052 (2)	1.28580 (19)	0.0448 (4)
C2	0.2945 (2)	1.1539 (2)	1.3905 (2)	0.0550 (5)
H2	0.2658	1.0855	1.4643	0.066*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0698 (4)	0.0491 (3)	0.0657 (3)	0.0012 (2)	−0.0008 (3)	0.0144 (2)
O1	0.0564 (8)	0.0409 (7)	0.0530 (7)	0.0005 (6)	0.0021 (6)	0.0062 (6)
O2	0.0636 (9)	0.0618 (8)	0.0435 (7)	0.0030 (7)	0.0058 (6)	0.0027 (6)
N1	0.0400 (8)	0.0382 (7)	0.0443 (8)	−0.0025 (6)	−0.0040 (6)	0.0007 (6)
N2	0.0542 (10)	0.0472 (8)	0.0510 (9)	0.0000 (7)	0.0033 (7)	0.0038 (7)
C3	0.0527 (12)	0.0641 (13)	0.0588 (12)	−0.0051 (10)	0.0000 (10)	−0.0152 (10)
C4	0.0564 (12)	0.0483 (11)	0.0706 (14)	0.0004 (9)	−0.0031 (11)	−0.0086 (10)
C5	0.0533 (11)	0.0406 (10)	0.0595 (12)	−0.0028 (8)	−0.0022 (9)	−0.0016 (8)
C6	0.0390 (9)	0.0390 (9)	0.0457 (9)	−0.0064 (7)	−0.0090 (8)	−0.0040 (7)
C7	0.0424 (9)	0.0374 (8)	0.0418 (9)	−0.0083 (7)	−0.0102 (7)	0.0014 (7)
C8	0.0399 (9)	0.0423 (9)	0.0408 (9)	−0.0074 (7)	−0.0080 (7)	0.0018 (7)
C9	0.0382 (9)	0.0446 (9)	0.0387 (9)	−0.0061 (7)	−0.0045 (7)	−0.0033 (7)
C17	0.0415 (9)	0.0453 (9)	0.0383 (9)	−0.0077 (8)	−0.0034 (7)	−0.0001 (7)
C16	0.0365 (9)	0.0454 (9)	0.0455 (9)	−0.0065 (7)	−0.0045 (7)	−0.0055 (7)
C11	0.0433 (10)	0.0538 (11)	0.0479 (10)	−0.0055 (8)	−0.0036 (8)	−0.0017 (8)
C12	0.0573 (13)	0.0732 (14)	0.0548 (12)	−0.0021 (11)	0.0098 (10)	−0.0084 (10)
C13	0.0588 (13)	0.0673 (14)	0.0755 (15)	0.0068 (11)	0.0050 (12)	−0.0180 (12)
C15	0.0502 (11)	0.0470 (10)	0.0565 (11)	−0.0026 (8)	−0.0045 (9)	−0.0004 (8)
C14	0.0574 (13)	0.0497 (11)	0.0767 (15)	0.0034 (9)	−0.0046 (11)	−0.0071 (10)
C10	0.0570 (12)	0.0520 (11)	0.0474 (10)	−0.0034 (9)	0.0016 (9)	0.0047 (8)
C1	0.0434 (10)	0.0444 (9)	0.0468 (10)	−0.0065 (8)	−0.0095 (8)	−0.0021 (8)
C2	0.0557 (12)	0.0625 (12)	0.0458 (10)	−0.0125 (10)	−0.0030 (9)	−0.0012 (9)

Geometric parameters (Å, º) top

Cl1—C1	1.7221 (17)	C9—C17	1.337 (2)
O1—C7	1.352 (2)	C9—C10	1.504 (3)
O1—N2	1.407 (2)	C17—C16	1.445 (2)
O2—C11	1.370 (2)	C17—H17	0.9300
O2—C10	1.434 (2)	C16—C11	1.394 (3)
N1—C7	1.297 (2)	C16—C15	1.396 (2)
N1—C8	1.370 (2)	C11—C12	1.379 (3)
N2—C8	1.308 (2)	C12—C13	1.375 (3)
C3—C2	1.375 (3)	C12—H12	0.9300
C3—C4	1.379 (3)	C13—C14	1.375 (3)
C3—H3	0.9300	C13—H13	0.9300
C4—C5	1.360 (3)	C15—C14	1.383 (3)
C4—H4	0.9300	C15—H15	0.9300
C5—C6	1.403 (2)	C14—H14	0.9300
C5—H5	0.9300	C10—H10A	0.9700
C6—C1	1.402 (3)	C10—H10B	0.9700
C6—C7	1.452 (2)	C1—C2	1.390 (3)
C8—C9	1.454 (2)	C2—H2	0.9300

C7—O1—N2	106.58 (12)	C11—C16—C17	118.38 (16)
C11—O2—C10	117.19 (14)	C15—C16—C17	123.41 (17)
C7—N1—C8	103.21 (14)	O2—C11—C12	117.82 (17)
C8—N2—O1	103.13 (13)	O2—C11—C16	120.90 (16)
C2—C3—C4	119.87 (19)	C12—C11—C16	121.14 (18)
C2—C3—H3	120.1	C13—C12—C11	119.4 (2)
C4—C3—H3	120.1	C13—C12—H12	120.3
C5—C4—C3	119.97 (18)	C11—C12—H12	120.3
C5—C4—H4	120.0	C14—C13—C12	121.0 (2)
C3—C4—H4	120.0	C14—C13—H13	119.5
C4—C5—C6	122.36 (19)	C12—C13—H13	119.5
C4—C5—H5	118.8	C14—C15—C16	120.9 (2)
C6—C5—H5	118.8	C14—C15—H15	119.6
C1—C6—C5	116.77 (17)	C16—C15—H15	119.6
C1—C6—C7	123.92 (15)	C13—C14—C15	119.4 (2)
C5—C6—C7	119.31 (16)	C13—C14—H14	120.3
N1—C7—O1	112.46 (15)	C15—C14—H14	120.3
N1—C7—C6	131.83 (16)	O2—C10—C9	112.57 (15)
O1—C7—C6	115.70 (14)	O2—C10—H10A	109.1
N2—C8—N1	114.61 (15)	C9—C10—H10A	109.1
N2—C8—C9	121.46 (16)	O2—C10—H10B	109.1
N1—C8—C9	123.93 (15)	C9—C10—H10B	109.1
C17—C9—C8	122.38 (16)	H10A—C10—H10B	107.8
C17—C9—C10	119.06 (16)	C2—C1—C6	120.70 (17)
C8—C9—C10	118.51 (15)	C2—C1—Cl1	117.01 (15)
C9—C17—C16	120.03 (16)	C6—C1—Cl1	122.29 (14)
C9—C17—H17	120.0	C3—C2—C1	120.32 (19)
C16—C17—H17	120.0	C3—C2—H2	119.8
C11—C16—C15	118.04 (17)	C1—C2—H2	119.8

C7—O1—N2—C8	0.60 (18)	C9—C17—C16—C15	172.52 (17)
C2—C3—C4—C5	0.4 (3)	C10—O2—C11—C12	−159.35 (17)
C3—C4—C5—C6	−0.5 (3)	C10—O2—C11—C16	24.9 (3)
C4—C5—C6—C1	−0.2 (3)	C15—C16—C11—O2	177.84 (16)
C4—C5—C6—C7	−179.70 (17)	C17—C16—C11—O2	2.3 (3)
C8—N1—C7—O1	0.53 (18)	C15—C16—C11—C12	2.2 (3)
C8—N1—C7—C6	−178.65 (17)	C17—C16—C11—C12	−173.26 (17)
N2—O1—C7—N1	−0.73 (19)	O2—C11—C12—C13	−176.98 (19)
N2—O1—C7—C6	178.58 (14)	C16—C11—C12—C13	−1.2 (3)
C1—C6—C7—N1	−1.2 (3)	C11—C12—C13—C14	−0.8 (4)
C5—C6—C7—N1	178.26 (17)	C11—C16—C15—C14	−1.3 (3)
C1—C6—C7—O1	179.69 (15)	C17—C16—C15—C14	173.99 (18)
C5—C6—C7—O1	−0.9 (2)	C12—C13—C14—C15	1.7 (4)
O1—N2—C8—N1	−0.3 (2)	C16—C15—C14—C13	−0.7 (3)
O1—N2—C8—C9	179.76 (15)	C11—O2—C10—C9	−40.1 (2)
C7—N1—C8—N2	−0.1 (2)	C17—C9—C10—O2	30.5 (2)
C7—N1—C8—C9	179.81 (16)	C8—C9—C10—O2	−152.22 (15)
N2—C8—C9—C17	178.75 (16)	C5—C6—C1—C2	1.1 (3)
N1—C8—C9—C17	−1.2 (3)	C7—C6—C1—C2	−179.50 (16)
N2—C8—C9—C10	1.6 (3)	C5—C6—C1—Cl1	−179.00 (13)
N1—C8—C9—C10	−178.30 (16)	C7—C6—C1—Cl1	0.4 (2)
C8—C9—C17—C16	177.80 (15)	C4—C3—C2—C1	0.4 (3)
C10—C9—C17—C16	−5.1 (3)	C6—C1—C2—C3	−1.2 (3)
C9—C17—C16—C11	−12.2 (3)	Cl1—C1—C2—C3	178.89 (15)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···O1ⁱ	0.93	2.62	3.389 (2)	140
C14—H14···Cl1ⁱⁱ	0.93	2.94	3.625 (2)	132
C2—H2···O2ⁱⁱⁱ	0.93	2.67	3.550 (2)	158

Symmetry codes: (i) −x+1, −y+3, −z+2; (ii) −x+2, −y+1, −z+2; (iii) x−1, y, z+1.

π–π interaction details (Å) top

Cg1 and Cg2 are the centroid of the C7/N1/C8/N2/O2 and C11–C16 rings, respectively

Centroid (Cg)	Centroid (Cg)	Cg···Cg distance	Dihedral angle (°)	Slippage distance
Cg1	Cg2ⁱ	3.9370 (11)	14.57 (10)	1.69
Cg2	Cg1ⁱ	3.9370 (11)	14.57 (10)	2.318

Symmetry code: (i) -x, -y, -z.

Acknowledgements

We thank the School of Chemistry, University of Hyderabad for the single-crystal X-ray data collection.

Funding information

Funding for this research was provided by: Council of Scientific and Industrial Research (grant No. 02(0218)/14/EMR-II to SM; Fast Track grant No. SB/FT/CS-87/2012 to SM); Council of Scientific and Industrial Research (grant No. 02(0134)/13/EMR-II to SN); Defence Research and Development Organisation (grant no. ERIP/ER/1203083/M/01/1643 to SM and SN).

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