1-{[3-(Thio­phen-2-yl)-4,5-di­hydro-1,2-oxazol-5-yl]methyl}-2,3-dihydro-1H-indole-2,3-dione

Rayni, I.; El Bakri, Y.; Sebhaoui, J.; El Bourakadi, K.; Essassi, E.M.; Mague, J.T.

doi:10.1107/S2414314617003157

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 2| Part 3| March 2017| x170315

https://doi.org/10.1107/S2414314617003157

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1-{[3-(Thiophen-2-yl)-4,5-dihydro-1,2-oxazol-5-yl]methyl}-2,3-dihydro-1H-indole-2,3-dione

Ibtissam Rayni,^a ^* Youness El Bakri,^a Jihad Sebhaoui,^a Khadija El Bourakadi,^a El Mokhtar Essassi ^a and Joel T. Mague ^b

^aLaboratoire de Chimie Organique Hétérocyclique, URAC 21, Pôle de Compétence Pharmacochimie, Av Ibn Battouta, BP 1014, Faculté des Sciences, Mohammed V University, Rabat, Morocco, and ^bDepartment of Chemistry, Tulane University, New Orleans, LA 70118, USA
^*Correspondence e-mail: irayni@yahoo.fr

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 18 February 2017; accepted 25 February 2017; online 13 October 2017)

In the title compound, C₁₆H₁₂N₂O₃S, the indoline and thiophene rings are inclined to one another by 2.01 (2)°. The isoxazole ring adopts an envelope conformation, with the methine C atom as the flap, and its mean plane is inclined to the thiophene and indoline ring mean planes by 19.78 (14) and 20.83 (12)°, respectively. In the crystal, molecules are linked by C—H⋯O hydrogen bonds involving the same acceptor atom, forming chains propagating along [010]. The chains are linked by further C—H⋯O hydrogen bonds, forming slabs parallel to the (-103) plane. The slabs are linked by offset π–π interactions [intercentroid distance = 3.792 (1) Å], forming a three-dimensional supramolecular structure.

Keywords: crystal structure; indoline; isoxazole; thiophene; hydrogen bonding; offset π–π interactions.

CCDC reference: 1534733

Structure description

Isatin (indoline-2,3-dione) is a core constituent of many alkaloids and drugs (Aboul-Fadl et al., 2010 ), as well as dyes, pesticides and analytical reagents. Literature surveys reveal that various derivatives of isatin possess diverse biological activities, such as antibacterial, antifungal, antiviral, anti-HIV (Bal et al., 2005 ), anti-microbacterial, anticancer (Gürsoy & Karalı, 2003 ), anti-inflammatory (Sridhar & Ramesh, 2001 ) and anticonvulsant activities (Verma et al., 2004 ). Continuing our research on the synthesis of new heterocyclic systems containing isatin and other moieties (Alsubari et al., 2009 ; Bouhfid et al., 2006 ), we report herein on the synthesis and crystal structure of the title compound, Fig. 1.

Figure 1
The molecular structure of the title compound, with the atom labelling and 40% probability displacement ellipsoids.

In the title compound, the indole ring system is almost planar as expected (r.m.s. deviation = 0.023 Å). The dihedral angle between this plane and that of the thiophene ring (r.m.s. deviation = 0.012 Å) is 2.01 (2)°. Puckering analysis of the isoxazole ring [parameters Q(2) = 0.175 (2) Å and φ(2) = 326.2 (8)°], indicates that it has an envelope conformation with atom C10 as the flap. Its mean plane is inclined to the thiophene and indoline ring mean planes by 19.78 (14) and 20.83 (12)°, respectively.

In the crystal, the combination of C2—H2⋯O2ⁱ, C9—H9A⋯O2ⁱ and C16—H16⋯O1ⁱⁱ hydrogen bonds (Table 1) forms stepped layers, or slabs two molecules thick, which are oriented parallel to ( $[\overline{1}]$ 03); as shown in Fig. 2. These layers are associated through offset π-stacking interactions, involving inversion-related indole rings in adjacent layers, forming a supramolecular three-dimensional structure [Cg⋯Cgⁱⁱⁱ = 3.792 (1) Å, Cg is the centroid of the N1/C1–C8 ring, interplanar distance = 3.479 (1) Å, slippage = 1.508 Å, symmetry code (iii): −x + 2, −y + 1, −z + 1].

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯O2ⁱ	0.88 (3)	2.60 (3)	3.455 (3)	162 (2)
C9—H9A⋯O2ⁱ	0.98 (3)	2.39 (3)	3.297 (3)	153.7 (19)
C16—H16⋯O1ⁱⁱ	0.93	2.49	3.212 (4)	134
Symmetry codes: (i) $[-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) $[x-{\script{3\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Figure 2
The partial view along the a axis of the crystal packing of the title compound. The hydrogen bonds are shown as dashed lines (see Table 1

Synthesis and crystallization

To a solution of 0.4 g (2.18 mmol) of 1-allylindoline-2,3-dione and 0.5 g (4 mmol) of 2-thiophenecarboxaldehyde oxime in 15 ml of chloroform, were added 15 ml of bleach (24% weight) with a dropping funnel. The mixture was stirred for 4 h at 273 K. The solution was then concentrated to dryness under reduced pressure and the residue extracted with chloroform. The product isolated was chromatographed on a silica column (eluent: hexane/ethyl acetate 95:5 v/v). The solid obtained was crystallized from ethanol solution to give colourless rod-like crystals of the title compound.

Refinement

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

Table 2
Experimental details

Crystal data
Chemical formula	C₁₆H₁₂N₂O₃S
M_r	312.34
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	298
a, b, c (Å)	7.3834 (2), 11.7331 (3), 16.9144 (4)
β (°)	101.731 (1)
V (Å³)	1434.69 (6)
Z	4
Radiation type	Cu Kα
μ (mm⁻¹)	2.14
Crystal size (mm)	0.24 × 0.19 × 0.14

Data collection
Diffractometer	Bruker D8 VENTURE PHOTON 100 CMOS
Absorption correction	Multi-scan (SADABS; Bruker, 2016 )
T_min, T_max	0.64, 0.76
No. of measured, independent and observed [I > 2σ(I)] reflections	10930, 2899, 2500
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.057, 0.166, 1.06
No. of reflections	2899
No. of parameters	235
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.80, −0.38
Computer programs: APEX3 and SAINT (Bruker, 2016), SHELXT (Sheldrick, 2015a ), SHELXL2014 (Sheldrick, 2015b ), DIAMOND (Brandenburg & Putz, 2012 ) and SHELXTL (Sheldrick, 2008 ).

Structural data

CCDC reference: 1534733

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S2414314617003157/su4133sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617003157/su4133Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314617003157/su4133Isup3.cdx

Supporting information file. DOI: https://doi.org/10.1107/S2414314617003157/su4133Isup4.cml

checkCIF report

Computing details top

Data collection: APEX3 (Bruker, 2016); cell refinement: SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: DIAMOND (Brandenburg & Putz, 2012); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

1-{[3-(Thiophen-2-yl)-4,5-dihydro-1,2-oxazol-5-yl]methyl}-2,3-dihydro-1H-indole-2,3-dione top

Crystal data top

C₁₆H₁₂N₂O₃S	F(000) = 648
M_r = 312.34	D_x = 1.446 Mg m⁻³
Monoclinic, P2₁/n	Cu Kα radiation, λ = 1.54178 Å
a = 7.3834 (2) Å	Cell parameters from 8282 reflections
b = 11.7331 (3) Å	θ = 3.8–74.3°
c = 16.9144 (4) Å	µ = 2.14 mm⁻¹
β = 101.731 (1)°	T = 298 K
V = 1434.69 (6) Å³	Rod, colourless
Z = 4	0.24 × 0.19 × 0.14 mm

Data collection top

Bruker D8 VENTURE PHOTON 100 CMOS diffractometer	2899 independent reflections
Radiation source: INCOATEC IµS micro-focus source	2500 reflections with I > 2σ(I)
Mirror monochromator	R_int = 0.031
Detector resolution: 10.4167 pixels mm^-1	θ_max = 74.7°, θ_min = 4.6°
ω scans	h = −9→9
Absorption correction: multi-scan (SADABS; Bruker, 2016)	k = −14→14
T_min = 0.64, T_max = 0.76	l = −18→20
10930 measured reflections

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)] = 0.057	Hydrogen site location: mixed
wR(F²) = 0.166	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	w = 1/[σ²(F_o²) + (0.089P)² + 0.7078P] where P = (F_o² + 2F_c²)/3
2899 reflections	(Δ/σ)_max < 0.001
235 parameters	Δρ_max = 0.80 e Å⁻³
0 restraints	Δρ_min = −0.38 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. The H-atoms of the thiophene moiety, although located in a difference map, did not refine satisfactorily and so were included as riding contributions in idealized positions.

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

	x	y	z	U_iso*/U_eq
S1	−0.04891 (11)	0.36107 (6)	0.11798 (5)	0.0697 (3)
O1	1.1460 (3)	0.26341 (19)	0.43119 (14)	0.0835 (7)
O2	0.8130 (3)	0.26371 (15)	0.30166 (14)	0.0718 (5)
O3	0.4468 (2)	0.41608 (18)	0.32154 (12)	0.0679 (6)
N1	0.8448 (2)	0.45816 (15)	0.31846 (11)	0.0434 (4)
N2	0.2829 (3)	0.39068 (19)	0.26398 (14)	0.0600 (6)
C1	0.9740 (3)	0.53126 (18)	0.36675 (12)	0.0410 (5)
C2	0.9783 (3)	0.6487 (2)	0.36514 (16)	0.0526 (6)
H2	0.900 (4)	0.691 (2)	0.3307 (18)	0.063 (8)*
C3	1.1224 (4)	0.7019 (3)	0.41754 (19)	0.0687 (8)
H3	1.130 (5)	0.778 (3)	0.415 (2)	0.081 (10)*
C4	1.2542 (4)	0.6412 (3)	0.47017 (19)	0.0729 (8)
H4	1.347 (5)	0.685 (3)	0.508 (2)	0.082 (10)*
C5	1.2494 (3)	0.5240 (3)	0.47092 (16)	0.0640 (7)
H5	1.332 (5)	0.486 (3)	0.506 (2)	0.083 (10)*
C6	1.1086 (3)	0.4687 (2)	0.41850 (13)	0.0486 (5)
C7	1.0666 (4)	0.3480 (2)	0.40177 (16)	0.0560 (6)
C8	0.8915 (3)	0.34648 (19)	0.33422 (15)	0.0509 (5)
C9	0.6847 (3)	0.4973 (2)	0.26000 (13)	0.0445 (5)
H9A	0.715 (3)	0.566 (2)	0.2327 (15)	0.048 (6)*
H9B	0.656 (4)	0.439 (2)	0.2200 (16)	0.053 (7)*
C10	0.5214 (3)	0.5228 (2)	0.29834 (16)	0.0525 (6)
H10	0.550 (4)	0.557 (3)	0.3435 (18)	0.062 (8)*
C11	0.3615 (3)	0.5784 (2)	0.24054 (18)	0.0553 (6)
H11A	0.299 (5)	0.641 (3)	0.267 (2)	0.102 (12)*
H11B	0.403 (4)	0.607 (3)	0.1921 (19)	0.071 (8)*
C12	0.2347 (3)	0.47894 (19)	0.22011 (14)	0.0464 (5)
C13	0.0679 (3)	0.4814 (2)	0.15739 (14)	0.0492 (5)
C14	−0.0204 (3)	0.5768 (2)	0.12228 (15)	0.0567 (6)
H14	0.0221	0.6506	0.1345	0.068*
C15	−0.1833 (5)	0.5507 (3)	0.06558 (19)	0.0782 (9)
H15	−0.2618	0.6058	0.0376	0.094*
C16	−0.2132 (5)	0.4392 (3)	0.05624 (18)	0.0768 (8)
H16	−0.3124	0.4078	0.0201	0.092*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0667 (5)	0.0567 (4)	0.0878 (5)	−0.0080 (3)	0.0209 (4)	−0.0166 (3)
O1	0.0917 (15)	0.0672 (12)	0.0930 (15)	0.0322 (11)	0.0222 (12)	0.0312 (11)
O2	0.0805 (13)	0.0373 (9)	0.0984 (14)	−0.0077 (9)	0.0201 (11)	−0.0075 (9)
O3	0.0485 (9)	0.0835 (13)	0.0735 (12)	0.0074 (9)	0.0166 (8)	0.0340 (10)
N1	0.0412 (9)	0.0336 (9)	0.0540 (10)	−0.0005 (7)	0.0063 (8)	−0.0014 (7)
N2	0.0500 (11)	0.0611 (12)	0.0718 (13)	−0.0004 (9)	0.0190 (10)	0.0190 (10)
C1	0.0357 (9)	0.0419 (11)	0.0455 (11)	−0.0003 (8)	0.0087 (8)	−0.0038 (8)
C2	0.0526 (13)	0.0418 (12)	0.0615 (14)	−0.0012 (10)	0.0069 (11)	−0.0051 (10)
C3	0.0675 (17)	0.0587 (17)	0.0792 (18)	−0.0155 (13)	0.0131 (14)	−0.0221 (14)
C4	0.0537 (15)	0.095 (2)	0.0673 (17)	−0.0160 (15)	0.0061 (13)	−0.0243 (16)
C5	0.0410 (12)	0.096 (2)	0.0536 (14)	0.0060 (13)	0.0068 (10)	0.0028 (13)
C6	0.0397 (10)	0.0608 (14)	0.0466 (11)	0.0073 (9)	0.0119 (9)	0.0049 (10)
C7	0.0562 (13)	0.0540 (13)	0.0617 (14)	0.0152 (11)	0.0213 (11)	0.0148 (11)
C8	0.0543 (13)	0.0379 (11)	0.0640 (14)	0.0028 (9)	0.0204 (11)	0.0035 (10)
C9	0.0407 (10)	0.0453 (11)	0.0463 (11)	−0.0025 (9)	0.0060 (9)	−0.0013 (9)
C10	0.0458 (12)	0.0581 (14)	0.0528 (13)	0.0034 (10)	0.0078 (10)	−0.0025 (11)
C11	0.0437 (11)	0.0466 (13)	0.0729 (16)	0.0028 (10)	0.0053 (11)	0.0018 (11)
C12	0.0435 (11)	0.0455 (11)	0.0539 (12)	0.0016 (9)	0.0186 (9)	0.0027 (9)
C13	0.0490 (12)	0.0504 (12)	0.0506 (12)	−0.0040 (10)	0.0159 (10)	−0.0014 (9)
C14	0.0562 (13)	0.0495 (13)	0.0605 (14)	−0.0050 (10)	0.0025 (11)	0.0108 (10)
C15	0.0731 (18)	0.089 (2)	0.0645 (17)	−0.0021 (16)	−0.0043 (14)	0.0148 (15)
C16	0.0726 (18)	0.094 (2)	0.0610 (16)	−0.0175 (17)	0.0073 (13)	−0.0166 (15)

Geometric parameters (Å, º) top

S1—C16	1.699 (4)	C5—H5	0.88 (4)
S1—C13	1.717 (2)	C6—C7	1.465 (4)
O1—C7	1.207 (3)	C7—C8	1.542 (4)
O2—C8	1.205 (3)	C9—C10	1.510 (3)
O3—N2	1.422 (3)	C9—H9A	0.98 (3)
O3—C10	1.454 (3)	C9—H9B	0.96 (3)
N1—C8	1.367 (3)	C10—C11	1.519 (3)
N1—C1	1.413 (3)	C10—H10	0.85 (3)
N1—C9	1.453 (3)	C11—C12	1.493 (3)
N2—C12	1.282 (3)	C11—H11A	1.02 (4)
C1—C2	1.379 (3)	C11—H11B	0.99 (3)
C1—C6	1.393 (3)	C12—C13	1.453 (3)
C2—C3	1.387 (4)	C13—C14	1.369 (3)
C2—H2	0.88 (3)	C14—C15	1.411 (4)
C3—C4	1.376 (5)	C14—H14	0.9300
C3—H3	0.89 (4)	C15—C16	1.331 (5)
C4—C5	1.376 (5)	C15—H15	0.9300
C4—H4	0.98 (3)	C16—H16	0.9300
C5—C6	1.384 (4)

C16—S1—C13	91.96 (14)	C10—C9—H9A	108.8 (14)
N2—O3—C10	108.19 (17)	N1—C9—H9B	106.8 (16)
C8—N1—C1	110.79 (18)	C10—C9—H9B	111.4 (15)
C8—N1—C9	125.00 (19)	H9A—C9—H9B	107 (2)
C1—N1—C9	124.21 (18)	O3—C10—C9	108.9 (2)
C12—N2—O3	109.0 (2)	O3—C10—C11	104.84 (19)
C2—C1—C6	121.5 (2)	C9—C10—C11	113.1 (2)
C2—C1—N1	127.7 (2)	O3—C10—H10	102 (2)
C6—C1—N1	110.8 (2)	C9—C10—H10	114 (2)
C1—C2—C3	117.0 (3)	C11—C10—H10	113 (2)
C1—C2—H2	123.7 (19)	C12—C11—C10	100.50 (19)
C3—C2—H2	119.1 (19)	C12—C11—H11A	110 (2)
C4—C3—C2	122.1 (3)	C10—C11—H11A	113 (2)
C4—C3—H3	121 (2)	C12—C11—H11B	111.0 (18)
C2—C3—H3	117 (2)	C10—C11—H11B	110.4 (18)
C5—C4—C3	120.4 (3)	H11A—C11—H11B	112 (3)
C5—C4—H4	122.0 (19)	N2—C12—C13	122.2 (2)
C3—C4—H4	117.5 (19)	N2—C12—C11	114.2 (2)
C4—C5—C6	118.7 (3)	C13—C12—C11	123.5 (2)
C4—C5—H5	120 (2)	C14—C13—C12	126.3 (2)
C6—C5—H5	121 (2)	C14—C13—S1	110.26 (19)
C5—C6—C1	120.2 (2)	C12—C13—S1	123.45 (18)
C5—C6—C7	132.8 (2)	C13—C14—C15	112.5 (3)
C1—C6—C7	107.0 (2)	C13—C14—H14	123.7
O1—C7—C6	130.5 (3)	C15—C14—H14	123.7
O1—C7—C8	124.1 (3)	C16—C15—C14	113.0 (3)
C6—C7—C8	105.47 (18)	C16—C15—H15	123.5
O2—C8—N1	127.2 (2)	C14—C15—H15	123.5
O2—C8—C7	126.9 (2)	C15—C16—S1	112.2 (2)
N1—C8—C7	105.9 (2)	C15—C16—H16	123.9
N1—C9—C10	112.35 (19)	S1—C16—H16	123.9
N1—C9—H9A	110.3 (14)

C10—O3—N2—C12	−12.4 (3)	O1—C7—C8—N1	179.6 (2)
C8—N1—C1—C2	176.5 (2)	C6—C7—C8—N1	−1.1 (2)
C9—N1—C1—C2	−3.3 (3)	C8—N1—C9—C10	96.1 (3)
C8—N1—C1—C6	−2.0 (2)	C1—N1—C9—C10	−84.1 (3)
C9—N1—C1—C6	178.19 (19)	N2—O3—C10—C9	−103.2 (2)
C6—C1—C2—C3	−0.2 (4)	N2—O3—C10—C11	18.1 (3)
N1—C1—C2—C3	−178.6 (2)	N1—C9—C10—O3	−71.4 (2)
C1—C2—C3—C4	−1.2 (4)	N1—C9—C10—C11	172.41 (19)
C2—C3—C4—C5	1.7 (5)	O3—C10—C11—C12	−16.3 (2)
C3—C4—C5—C6	−0.7 (4)	C9—C10—C11—C12	102.3 (2)
C4—C5—C6—C1	−0.6 (4)	O3—N2—C12—C13	−177.69 (19)
C4—C5—C6—C7	177.5 (3)	O3—N2—C12—C11	0.9 (3)
C2—C1—C6—C5	1.1 (3)	C10—C11—C12—N2	10.0 (3)
N1—C1—C6—C5	179.7 (2)	C10—C11—C12—C13	−171.4 (2)
C2—C1—C6—C7	−177.5 (2)	N2—C12—C13—C14	161.9 (2)
N1—C1—C6—C7	1.2 (2)	C11—C12—C13—C14	−16.6 (4)
C5—C6—C7—O1	1.0 (5)	N2—C12—C13—S1	−16.9 (3)
C1—C6—C7—O1	179.2 (3)	C11—C12—C13—S1	164.62 (19)
C5—C6—C7—C8	−178.3 (2)	C16—S1—C13—C14	−0.3 (2)
C1—C6—C7—C8	−0.1 (2)	C16—S1—C13—C12	178.6 (2)
C1—N1—C8—O2	−177.7 (2)	C12—C13—C14—C15	−177.5 (2)
C9—N1—C8—O2	2.1 (4)	S1—C13—C14—C15	1.4 (3)
C1—N1—C8—C7	1.8 (2)	C13—C14—C15—C16	−2.1 (4)
C9—N1—C8—C7	−178.35 (18)	C14—C15—C16—S1	1.9 (4)
O1—C7—C8—O2	−0.9 (4)	C13—S1—C16—C15	−0.9 (3)
C6—C7—C8—O2	178.4 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O2ⁱ	0.88 (3)	2.60 (3)	3.455 (3)	162 (2)
C9—H9A···O2ⁱ	0.98 (3)	2.39 (3)	3.297 (3)	153.7 (19)
C16—H16···O1ⁱⁱ	0.93	2.49	3.212 (4)	134

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

Acknowledgements

The support of NSF–MRI Grant No.1228232 for the purchase of the diffractometer and Tulane University for support of the Tulane Crystallography Laboratory are gratefully acknowledged.

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