3′,4′-Diphenyl-3H,4′H-spiro­[benzo[b]thio­phene-2,5′-isoxazol]-3-one

Bakhouch, M.; El Yazidi, M.; Al Houari, G.; Saadi, M.; El Ammari, L.

doi:10.1107/S2414314618010192

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 3| Part 7| July 2018| x181019

https://doi.org/10.1107/S2414314618010192

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3′,4′-Diphenyl-3H,4′H-spiro[benzo[b]thiophene-2,5′-isoxazol]-3-one

Mohamed Bakhouch,^a ^* Mohamed El Yazidi,^a Ghali Al Houari,^a Mohamed Saadi ^b and Lahcen El Ammari ^b

^aLaboratoire de Chimie Organique, Faculté des Sciences Dhar El Mahraz, Université Sidi Mohamed Ben Abdellah, BP 1796, 30000 Fès, Morocco, and ^bLaboratoire de Chimie Appliquée des Matériaux, Centres des Sciences des Matériaux, Faculty of Sciences, Mohammed V University in Rabat, Avenue Ibn Battouta, BP 1014, Rabat, Morocco
^*Correspondence e-mail: bakhouch_m@yahoo.com

Edited by J. Simpson, University of Otago, New Zealand (Received 10 July 2018; accepted 13 July 2018; online 20 July 2018)

The molecule of the title compound, C₂₂H₁₅NO₂S, is built up from a benzothiophene system linked to an isoxazoline ring which is connected to two phenyl rings. The benzothiophene system is essentially planar, while the isoxazoline ring displays an envelope conformation with the spiro C atom as the flap. The mean plane through the isoxazoline ring is slightly inclined to one phenyl ring by 5.74 (13)° and is approximately perpendicular [86.10 (10)°] to the fused ring system and to the other phenyl ring [84.31 (12)°]. In the crystal, molecules are linked together by C—H⋯O hydrogen bonds and by π–π interactions between the fused ring systems [intercentroid distance = 3.702 (2) Å], forming a three-dimensional network.

Keywords: crystal structutre; diphenyl; spiroisoxazolines; isoxazoline; hydrogen bonds; π–π interactions.

CCDC reference: 1855760

Structure description

Molecules containing an isoxazoline framework have been widely used as key building blocks for medicines. Among these compounds, spiroisoxazolines have shown strong bioactivities (Bennani et al., 2007 ; Al Houari et al., 2008 ; Hwang et al., 2005 ). For many years, our laboratory has accumulated much experience in the design and synthesis of heterocyclic systems with isoxazoline and pyrazoline rings through 1,3-dipolar cycloaddition and cyclocondensation reactions (El Yazidi et al., 2003 ; Bakhouch et al., 2014 , 2015 , 2017 ; Mahfoud et al., 2015 ). In a continuation of our previous work, and in an attempt to evaluate the reactivity of thioaurones with nitrile oxides as a dipole (Boughaleb et al., 2011 ), we describe herein the reaction of (Z)-2-benzylidenbenzo[b]thiophen-3(2H)-one with benzonitrile oxide in chloroform at low temperature. The title compound was obtained by regiospecific 1,3-dipolar cycloaddition. The results of the X-ray study were in perfect agreement with IR, ¹H NMR and ¹³C NMR spectroscopic analysis, which confirms the regiospecificity of the reaction.

The isoxazoline ring is linked to two phenyl rings and to a benzothiophene ring system, as shown in Fig. 1. The five-membred ring (N1/O1/C8–C10) adopts an envelope conformation with the spiro C8 atom as the flap. The total puckering amplitude for this ring is Q2 = 0.239 (2) Å and the spherical polar angle φ2 = 137.2 (5)° (Cremer & Pople, 1975 ). The benzothiophene system is nearly perpendicular to the mean plane through the isoxazoline ring (N1/O1/C8–C10) and to the C11–C16 phenyl ring, as indicated by the dihedral angles of 86.10 (10) and 87.46 (11)°, respectively, between them. The dihedral angle between the fused ring system and the C17–C22 phenyl ring is 65.80 (11)°.

Figure 1
A plot of the molecule of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented as small circles.

In the crystal, molecules are linked together by C9—H9⋯O1ⁱⁱ and C19—H19⋯O2ⁱ hydrogen bonds and by π–π interactions between inversion-related benzene rings of adjacent benzothiophene ring systems [intercentroid distance = 3.702 (2) Å] to form a three-dimensional network (Fig. 2 and Table 1).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C19—H19⋯O2ⁱ	0.93	2.62	3.462 (3)	152
C9—H9⋯O1ⁱⁱ	0.98	2.66	3.564 (2)	154
Symmetry codes: (i) x+1, y, z; (ii) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ .

Figure 2
Crystal packing for the title compound showing molecules linked by hydrogen bonds (dashed blue lines) and a π–π interaction (green line).

Synthesis and crystallization

In a 100 ml flask, 2 mmol of (Z)-2-benzylidenebenzo[b]thiophen-3-one and 2.2 mmol of benzonitrile oxide were dissolved in 20 ml of chloroform. The mixture was cooled to 273 K under magnetic stirring in an ice bath. Then 15 ml of bleach (NaOCl, 24%) was added drop-by-drop without exceeding a temperature of 278 K. The mixture was left stirring for 4 h at room temperature, washed with water until the pH was neutral and dried over sodium sulfate (Na₂SO₄). The solvent was then removed under reduced pressure and the resulting residue was crystallized from ethanol (yield: 90%; m.p. 495 K). Colourless block-like crystals were obtained by slow evaporation of the ethanolic solution.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₂₂H₁₅NO₂S
M_r	357.41
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	296
a, b, c (Å)	9.2650 (2), 10.3523 (2), 36.0698 (8)
V (Å³)	3459.60 (13)
Z	8
Radiation type	Mo Kα
μ (mm⁻¹)	0.20
Crystal size (mm)	0.35 × 0.28 × 0.25

Data collection
Diffractometer	Bruker X8 APEX
Absorption correction	Multi-scan (SADABS; Krause et al., 2015 )
T_min, T_max	0.639, 0.747
No. of measured, independent and observed [I > 2σ(I)] reflections	76407, 3811, 2597
R_int	0.089
(sin θ/λ)_max (Å⁻¹)	0.641

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.105, 1.06
No. of reflections	3811
No. of parameters	235
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.18, −0.26
Computer programs: APEX2 (Bruker, 2009 ), SAINT (Bruker, 2009), SHELXS2016 (Sheldrick, 2015a ), SHELXL2016 (Sheldrick, 2015b ), ORTEP-3 (Farrugia, 2012 ), Mercury (Macrae et al., 2008 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 1855760

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314618010192/sj4187sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314618010192/sj4187Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314618010192/sj4187Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS2016 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2016 (Sheldrick, 2015b); molecular graphics: ORTEP-3 (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: publCIF (Westrip, 2010).

3',4'-Diphenyl-3H,4'H-spiro[benzo[b]thiophene-2,5'-isoxazol]-3-one top

Crystal data top

C₂₂H₁₅NO₂S	D_x = 1.372 Mg m⁻³
M_r = 357.41	Melting point: 495 K
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
a = 9.2650 (2) Å	Cell parameters from 3811 reflections
b = 10.3523 (2) Å	θ = 3.0–27.1°
c = 36.0698 (8) Å	µ = 0.20 mm⁻¹
V = 3459.60 (13) Å³	T = 296 K
Z = 8	Block, colourless
F(000) = 1488	0.35 × 0.28 × 0.25 mm

Data collection top

Bruker X8 APEX diffractometer	3811 independent reflections
Radiation source: fine-focus sealed tube	2597 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.089
φ and ω scans	θ_max = 27.1°, θ_min = 3.0°
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	h = −11→11
T_min = 0.639, T_max = 0.747	k = −13→13
76407 measured reflections	l = −46→46

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) = 0.105	w = 1/[σ²(F_o²) + (0.0215P)² + 2.5234P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max = 0.001
3811 reflections	Δρ_max = 0.18 e Å⁻³
235 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
C1	0.2409 (3)	0.4525 (2)	0.52031 (6)	0.0450 (5)
C2	0.2733 (3)	0.4617 (3)	0.48281 (7)	0.0620 (7)
H2	0.351287	0.510587	0.474656	0.074*
C3	0.1865 (4)	0.3962 (3)	0.45792 (7)	0.0750 (9)
H3	0.207713	0.400469	0.432749	0.090*
C4	0.0696 (4)	0.3248 (3)	0.46947 (7)	0.0739 (9)
H4	0.012838	0.282128	0.452088	0.089*
C5	0.0360 (3)	0.3160 (2)	0.50654 (7)	0.0559 (7)
H5	−0.043069	0.268137	0.514492	0.067*
C6	0.1239 (2)	0.3807 (2)	0.53187 (6)	0.0399 (5)
C7	0.1038 (2)	0.3808 (2)	0.57209 (6)	0.0386 (5)
C8	0.2164 (2)	0.4696 (2)	0.59144 (6)	0.0372 (5)
C9	0.2811 (2)	0.40827 (19)	0.62647 (5)	0.0338 (4)
H9	0.274619	0.313886	0.625187	0.041*
C10	0.1760 (2)	0.4606 (2)	0.65481 (6)	0.0361 (5)
C11	0.1605 (2)	0.4157 (2)	0.69323 (6)	0.0414 (5)
C12	0.0655 (3)	0.4780 (3)	0.71734 (7)	0.0623 (7)
H12	0.010973	0.547609	0.708966	0.075*
C13	0.0521 (4)	0.4369 (3)	0.75341 (8)	0.0802 (10)
H13	−0.010154	0.480009	0.769415	0.096*
C14	0.1291 (4)	0.3337 (3)	0.76594 (8)	0.0788 (10)
H14	0.118796	0.306354	0.790355	0.095*
C15	0.2214 (3)	0.2704 (3)	0.74268 (7)	0.0706 (8)
H15	0.273459	0.199575	0.751241	0.085*
C16	0.2378 (3)	0.3114 (2)	0.70626 (6)	0.0519 (6)
H16	0.301303	0.268334	0.690577	0.062*
C17	0.4353 (2)	0.4498 (2)	0.63469 (6)	0.0370 (5)
C22	0.4642 (2)	0.5692 (2)	0.65033 (7)	0.0491 (6)
H22	0.388181	0.622907	0.657125	0.059*
C21	0.6048 (3)	0.6096 (3)	0.65596 (8)	0.0665 (8)
H21	0.623101	0.689521	0.666765	0.080*
C20	0.7171 (3)	0.5314 (3)	0.64558 (8)	0.0731 (9)
H20	0.811760	0.558786	0.649034	0.088*
C19	0.6900 (3)	0.4130 (3)	0.63010 (8)	0.0670 (8)
H19	0.766504	0.360381	0.623001	0.080*
C18	0.5501 (2)	0.3713 (3)	0.62498 (7)	0.0506 (6)
H18	0.532736	0.290003	0.614950	0.061*
N1	0.1012 (2)	0.55663 (18)	0.64309 (5)	0.0452 (5)
O1	0.13553 (17)	0.58038 (14)	0.60528 (4)	0.0479 (4)
O2	0.01376 (18)	0.32410 (17)	0.58958 (4)	0.0573 (5)
S1	0.34013 (7)	0.52549 (7)	0.55640 (2)	0.05418 (18)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0463 (12)	0.0488 (13)	0.0398 (12)	0.0096 (11)	0.0056 (11)	0.0066 (10)
C2	0.0635 (17)	0.0751 (18)	0.0475 (14)	0.0168 (15)	0.0149 (13)	0.0167 (14)
C3	0.111 (3)	0.081 (2)	0.0328 (13)	0.029 (2)	0.0067 (16)	0.0039 (14)
C4	0.114 (3)	0.0680 (18)	0.0396 (14)	0.0096 (19)	−0.0178 (17)	−0.0058 (13)
C5	0.0714 (18)	0.0473 (14)	0.0489 (14)	−0.0008 (13)	−0.0141 (13)	−0.0007 (11)
C6	0.0481 (13)	0.0367 (11)	0.0350 (11)	0.0038 (10)	−0.0022 (10)	0.0007 (9)
C7	0.0374 (11)	0.0405 (12)	0.0379 (11)	0.0005 (10)	−0.0016 (10)	0.0003 (9)
C8	0.0348 (11)	0.0393 (11)	0.0376 (11)	−0.0020 (9)	0.0025 (9)	−0.0007 (9)
C9	0.0326 (10)	0.0323 (10)	0.0366 (11)	0.0000 (9)	0.0026 (9)	−0.0011 (9)
C10	0.0280 (10)	0.0414 (12)	0.0388 (11)	−0.0031 (9)	0.0007 (9)	−0.0058 (9)
C11	0.0347 (11)	0.0504 (13)	0.0390 (12)	−0.0098 (10)	0.0047 (10)	−0.0072 (10)
C12	0.0607 (16)	0.0700 (17)	0.0562 (15)	−0.0021 (14)	0.0218 (13)	−0.0079 (13)
C13	0.089 (2)	0.096 (2)	0.0560 (18)	−0.016 (2)	0.0363 (17)	−0.0151 (17)
C14	0.093 (2)	0.104 (3)	0.0394 (15)	−0.031 (2)	0.0116 (16)	0.0003 (16)
C15	0.080 (2)	0.084 (2)	0.0477 (15)	−0.0050 (17)	−0.0041 (15)	0.0108 (14)
C16	0.0511 (14)	0.0647 (16)	0.0398 (12)	−0.0006 (12)	0.0003 (12)	−0.0028 (11)
C17	0.0301 (10)	0.0436 (12)	0.0371 (11)	0.0017 (9)	0.0014 (9)	0.0076 (9)
C22	0.0386 (12)	0.0511 (14)	0.0577 (15)	−0.0033 (11)	−0.0040 (11)	0.0001 (11)
C21	0.0526 (16)	0.0736 (18)	0.0733 (19)	−0.0251 (15)	−0.0138 (15)	0.0095 (15)
C20	0.0347 (14)	0.106 (3)	0.078 (2)	−0.0182 (16)	−0.0103 (14)	0.0378 (19)
C19	0.0351 (13)	0.094 (2)	0.0723 (19)	0.0148 (14)	0.0112 (13)	0.0296 (17)
C18	0.0408 (12)	0.0587 (15)	0.0522 (14)	0.0094 (11)	0.0071 (11)	0.0090 (12)
N1	0.0402 (10)	0.0518 (12)	0.0435 (11)	0.0055 (9)	0.0003 (9)	−0.0080 (9)
O1	0.0543 (10)	0.0428 (9)	0.0467 (9)	0.0107 (7)	−0.0041 (8)	−0.0014 (7)
O2	0.0514 (10)	0.0706 (11)	0.0499 (10)	−0.0228 (9)	0.0048 (8)	0.0013 (9)
S1	0.0460 (3)	0.0679 (4)	0.0486 (3)	−0.0160 (3)	0.0036 (3)	0.0130 (3)

Geometric parameters (Å, º) top

C1—C6	1.379 (3)	C11—C12	1.396 (3)
C1—C2	1.389 (3)	C12—C13	1.374 (4)
C1—S1	1.763 (2)	C12—H12	0.9300
C2—C3	1.383 (4)	C13—C14	1.362 (4)
C2—H2	0.9300	C13—H13	0.9300
C3—C4	1.376 (4)	C14—C15	1.366 (4)
C3—H3	0.9300	C14—H14	0.9300
C4—C5	1.376 (4)	C15—C16	1.389 (3)
C4—H4	0.9300	C15—H15	0.9300
C5—C6	1.395 (3)	C16—H16	0.9300
C5—H5	0.9300	C17—C18	1.383 (3)
C6—C7	1.463 (3)	C17—C22	1.385 (3)
C7—O2	1.199 (2)	C22—C21	1.383 (3)
C7—C8	1.555 (3)	C22—H22	0.9300
C8—O1	1.459 (2)	C21—C20	1.370 (4)
C8—C9	1.536 (3)	C21—H21	0.9300
C8—S1	1.802 (2)	C20—C19	1.371 (4)
C9—C10	1.512 (3)	C20—H20	0.9300
C9—C17	1.521 (3)	C19—C18	1.379 (4)
C9—H9	0.9800	C19—H19	0.9300
C10—N1	1.283 (3)	C18—H18	0.9300
C10—C11	1.469 (3)	N1—O1	1.421 (2)
C11—C16	1.378 (3)

C6—C1—C2	120.1 (2)	C12—C11—C10	120.2 (2)
C6—C1—S1	114.68 (16)	C13—C12—C11	120.2 (3)
C2—C1—S1	125.2 (2)	C13—C12—H12	119.9
C3—C2—C1	118.2 (3)	C11—C12—H12	119.9
C3—C2—H2	120.9	C14—C13—C12	120.7 (3)
C1—C2—H2	120.9	C14—C13—H13	119.7
C4—C3—C2	121.6 (2)	C12—C13—H13	119.7
C4—C3—H3	119.2	C13—C14—C15	120.1 (3)
C2—C3—H3	119.2	C13—C14—H14	120.0
C5—C4—C3	120.5 (3)	C15—C14—H14	120.0
C5—C4—H4	119.7	C14—C15—C16	120.2 (3)
C3—C4—H4	119.7	C14—C15—H15	119.9
C4—C5—C6	118.2 (3)	C16—C15—H15	119.9
C4—C5—H5	120.9	C11—C16—C15	120.4 (2)
C6—C5—H5	120.9	C11—C16—H16	119.8
C1—C6—C5	121.3 (2)	C15—C16—H16	119.8
C1—C6—C7	113.6 (2)	C18—C17—C22	118.6 (2)
C5—C6—C7	125.2 (2)	C18—C17—C9	120.4 (2)
O2—C7—C6	127.6 (2)	C22—C17—C9	120.90 (19)
O2—C7—C8	121.32 (19)	C21—C22—C17	120.8 (2)
C6—C7—C8	111.10 (18)	C21—C22—H22	119.6
O1—C8—C9	104.11 (15)	C17—C22—H22	119.6
O1—C8—C7	105.87 (16)	C20—C21—C22	119.8 (3)
C9—C8—C7	112.77 (16)	C20—C21—H21	120.1
O1—C8—S1	108.32 (13)	C22—C21—H21	120.1
C9—C8—S1	117.48 (14)	C21—C20—C19	120.0 (2)
C7—C8—S1	107.57 (14)	C21—C20—H20	120.0
C10—C9—C17	111.83 (16)	C19—C20—H20	120.0
C10—C9—C8	99.02 (16)	C20—C19—C18	120.5 (3)
C17—C9—C8	114.22 (16)	C20—C19—H19	119.8
C10—C9—H9	110.4	C18—C19—H19	119.8
C17—C9—H9	110.4	C19—C18—C17	120.3 (3)
C8—C9—H9	110.4	C19—C18—H18	119.8
N1—C10—C11	120.21 (19)	C17—C18—H18	119.8
N1—C10—C9	113.72 (18)	C10—N1—O1	109.23 (16)
C11—C10—C9	125.98 (19)	N1—O1—C8	107.90 (14)
C16—C11—C12	118.5 (2)	C1—S1—C8	92.77 (10)
C16—C11—C10	121.2 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C19—H19···O2ⁱ	0.93	2.62	3.462 (3)	152
C9—H9···O1ⁱⁱ	0.98	2.66	3.564 (2)	154

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

Acknowledgements

The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.

References

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