(Z)-2-(2-Chloro­benzyl­idene)-4-(prop-2-yn­yl)-2H-1,4-benzo­thia­zin-3(4H)-one

Sebbar, N.K.; Ellouz, M.; Ouzidan, Y.; Kaur, M.; Essassi, E.M.; Jasinski, J.P.

doi:10.1107/S2414314617008896

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 2| Part 6| June 2017| x170889

https://doi.org/10.1107/S2414314617008896

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(Z)-2-(2-Chlorobenzylidene)-4-(prop-2-ynyl)-2H-1,4-benzothiazin-3(4H)-one

Nada Kheira Sebbar,^a Mohamed Ellouz,^a ^* Younes Ouzidan,^b Manpreet Kaur,^c El Mokhtar Essassi ^a and Jerry P. Jasinski ^c

^aLaboratoire de Chimie Organique Hétérocyclique URAC 21, Pôle de Compétence Pharmacochimie, Av. Ibn Battouta, BP 1014, Faculté des Sciences, Université Mohammed V, Rabat, Morocco, ^bLaboratoire de Chimie Organique Appliquée, Faculté des Sciences et Techniques, Université Sidi Mohammed Ben Abdellah, Fès, Morocco, and ^cDepartment of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA
^*Correspondence e-mail: ellouz.chimie@gmail.com

Edited by J. Simpson, University of Otago, New Zealand (Received 7 June 2017; accepted 14 June 2017; online 27 June 2017)

In the title compound, C₁₈H₁₂ClNOS, the thiazine-3-one ring of the 1,4-thiazin-3-one moiety adopts a slightly distorted twist-boat conformation. The dihedral angle between the benzene rings is 86.2 (1)°. In the crystal, the crystal packing features a single weak C—H⋯O interaction and weak π–π stacking interactions.

Keywords: crystal structure; benzothiazine; hydrogen bond.

CCDC reference: 1556120

Structure description

The 1,4-benzothiazine ring system represents an important class of compounds, not only for their theoretical interest, but also for their analgesic (Wammack et al., 2002 ); anti-viral (Malagu et al., 1998 ; Rathore & Kumar, 2006 ) and anti-oxidant activities (Zia-ur-Rehman et al., 2009 ). Recently, related research has been focused on existing molecules and their modifications in order to reduce their side effects and to explore their other pharmacological and biological effects (Sebbar et al., 2016a ; Armenise et al., 2012 ). As a continuation of our research work on the development of N-substituted 1,4-benzothiazine derivatives and the evaluation of their potential pharmacological activities, we have studied the condensation reaction of propargyl bromide with (Z)-2-(2-chlorobenzylidene)-2H-1,4-benzothiazin-3(4H)-one under phase-transfer catalysis conditions using tetra-n-butylammonium bromide (TBAB) as a catalyst and potassium carbonate as the base, giving the title compound in good yield (Sebbar et al., 2016b , Ellouz et al., 2017a ,b ).

In the title compound (Fig. 1), the thiazine-3-one ring of the [1,4]thiazin-3-one moiety adopts a slightly distorted twist-boat conformation [puckering parameters: Q = 0.433 (2) Å, θ = 110.2 (2)° and φ = 196.4 (3)°]. The dihedral angle between the benzene rings is 86.2 (1)°. In the crystal, a single weak C18—H18⋯O1ⁱ interaction links the molecules into chains along the c-axis direction (Fig. 2, Table 1). In addition, π–π stacking interactions [Cg3⋯Cg3ⁱⁱⁱ = 3.8766 (2) Å; Cg3 is the centroid of the C10–C15 benzene ring; symmetry code: (iii) 1 − x, −y, −z] are also observed.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C18—H18⋯O1ⁱ	0.93	2.33	3.191 (3)	154
Symmetry codes: (i) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Figure 1
The structure of the title compound, showing the atom-numbering scheme, with displacement ellipsoids drawn at the 30% probability level.

Figure 2
The molecular packing of the title compound, viewed along the c axis. Dashed lines indicate weak intermolecular hydrogen bonds. H atoms not involved in these interactions have been omitted for clarity.

Synthesis and crystallization

To a mixture of (Z)-2-(2-chlorobenzylidene)-2H-1,4-benzothiazin-3(4H)-one (0.49 g, 1.5 mmol), potassium carbonate (0.41 g, 3 mmol) and tetra-n-butyl ammonium bromide (0.048 g, 0.15 mmol) in DMF (15 ml) was added propargyl bromide (3 mmol). Stirring was continued at room temperature for 24 h. The salts were removed by filtration and the filtrate was concentrated under reduced pressure. The residue was separated by chromatography on a column of silica gel with ethyl acetate–hexane (1/9) as the eluent. The solid product was purified by recrystallization from ethanol solution to afford yellow crystals in 90% yield.

Refinement

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

Table 2
Experimental details

Crystal data
Chemical formula	C₁₈H₁₂ClNOS
M_r	325.80
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	13.3937 (8), 8.9106 (4), 13.3940 (7)
β (°)	99.765 (5)
V (Å³)	1575.36 (15)
Z	4
Radiation type	Cu Kα
μ (mm⁻¹)	3.38
Crystal size (mm)	0.24 × 0.18 × 0.12

Data collection
Diffractometer	Rigaku Oxford Diffraction
Absorption correction	Multi-scan (CrysAlis PRO; Rigaku Oxford Diffraction, 2015 $[Rigaku Oxford Diffraction (2015). CrysAlis PRO. Rigaku Americas, The Woodlands, Texas, USA.]$ )
T_min, T_max	0.481, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	10186, 3031, 2559
R_int	0.037
(sin θ/λ)_max (Å⁻¹)	0.616

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.049, 0.138, 1.03
No. of reflections	3031
No. of parameters	199
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.32, −0.29
Computer programs: CrysAlis PRO (Rigaku Oxford Diffraction, 2015 $[Rigaku Oxford Diffraction (2015). CrysAlis PRO. Rigaku Americas, The Woodlands, Texas, USA.]$ ), SHELXT (Sheldrick, 2015a ), SHELXL2014 (Sheldrick, 2015b ) and OLEX2 (Dolomanov et al., 2009 ).

Structural data

CCDC reference: 1556120

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314617008896/sj4119sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617008896/sj4119Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314617008896/sj4119Isup3.cdx

Supporting information file. DOI: https://doi.org/10.1107/S2414314617008896/sj4119Isup4.cml

checkCIF report

Computing details top

Data collection: CrysAlis PRO (Rigaku Oxford Diffraction, 2015); cell refinement: CrysAlis PRO (Rigaku Oxford Diffraction, 2015); data reduction: CrysAlis PRO (Rigaku Oxford Diffraction, 2015); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

(Z)-2-(2-Chlorobenzylidene)-4-(prop-2-ynyl)-2H-1,4-benzothiazin-3(4H)-one top

Crystal data top

C₁₈H₁₂ClNOS	F(000) = 672
M_r = 325.80	D_x = 1.374 Mg m⁻³
Monoclinic, P2₁/c	Cu Kα radiation, λ = 1.54184 Å
a = 13.3937 (8) Å	Cell parameters from 3922 reflections
b = 8.9106 (4) Å	θ = 3.4–71.2°
c = 13.3940 (7) Å	µ = 3.38 mm⁻¹
β = 99.765 (5)°	T = 293 K
V = 1575.36 (15) Å³	Prism, yellow
Z = 4	0.24 × 0.18 × 0.12 mm

Data collection top

Rigaku Oxford Diffraction diffractometer	3031 independent reflections
Radiation source: fine-focus sealed X-ray tube, Enhance (Cu) X-ray Source	2559 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.037
Detector resolution: 16.0416 pixels mm^-1	θ_max = 71.7°, θ_min = 3.4°
ω scans	h = −15→16
Absorption correction: multi-scan (CrysAlis PRO; Rigaku Oxford Diffraction, 2015)	k = −7→10
T_min = 0.481, T_max = 1.000	l = −16→16
10186 measured reflections

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.049	H-atom parameters constrained
wR(F²) = 0.138	w = 1/[σ²(F_o²) + (0.0723P)² + 0.4736P] where P = (F_o² + 2F_c²)/3
S = 1.03	(Δ/σ)_max < 0.001
3031 reflections	Δρ_max = 0.32 e Å⁻³
199 parameters	Δρ_min = −0.29 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	0.42965 (6)	0.52359 (13)	0.25072 (7)	0.0975 (3)
S1	0.77650 (5)	0.76330 (7)	0.34112 (4)	0.0610 (2)
O1	0.78762 (15)	0.34054 (17)	0.26884 (13)	0.0621 (5)
N1	0.86271 (13)	0.53717 (19)	0.20648 (13)	0.0432 (4)
C1	0.79562 (16)	0.4761 (2)	0.26214 (15)	0.0447 (5)
C2	0.73317 (17)	0.5795 (2)	0.31387 (15)	0.0475 (5)
C3	0.82700 (15)	0.8022 (2)	0.23221 (15)	0.0435 (4)
C4	0.83237 (19)	0.9512 (3)	0.2039 (2)	0.0568 (6)
H4	0.8051	1.0256	0.2399	0.068*
C5	0.8780 (2)	0.9898 (3)	0.1227 (2)	0.0715 (8)
H5	0.8823	1.0900	0.1044	0.086*
C6	0.9169 (3)	0.8799 (3)	0.0693 (2)	0.0763 (9)
H6	0.9479	0.9058	0.0147	0.092*
C7	0.9106 (2)	0.7318 (3)	0.0955 (2)	0.0603 (6)
H7	0.9364	0.6584	0.0575	0.072*
C8	0.86627 (15)	0.6896 (2)	0.17806 (15)	0.0415 (4)
C9	0.64950 (19)	0.5274 (3)	0.34302 (17)	0.0555 (5)
H9	0.6326	0.4276	0.3283	0.067*
C10	0.58172 (19)	0.6140 (3)	0.39636 (18)	0.0563 (6)
C11	0.4785 (2)	0.6218 (3)	0.3599 (2)	0.0633 (6)
C12	0.4138 (2)	0.7054 (4)	0.4076 (3)	0.0773 (8)
H12	0.3451	0.7098	0.3812	0.093*
C13	0.4521 (3)	0.7823 (4)	0.4946 (3)	0.0824 (9)
H13	0.4090	0.8391	0.5273	0.099*
C14	0.5533 (3)	0.7758 (4)	0.5334 (2)	0.0815 (9)
H14	0.5789	0.8271	0.5926	0.098*
C15	0.6173 (2)	0.6930 (4)	0.4845 (2)	0.0707 (7)
H15	0.6861	0.6900	0.5113	0.085*
C16	0.92210 (18)	0.4284 (3)	0.15800 (18)	0.0537 (5)
H16A	0.9874	0.4722	0.1533	0.064*
H16B	0.9341	0.3399	0.2005	0.064*
C17	0.87254 (19)	0.3833 (2)	0.05696 (18)	0.0535 (5)
C18	0.8334 (2)	0.3439 (3)	−0.0242 (2)	0.0689 (7)
H18	0.8025	0.3128	−0.0883	0.083*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0702 (5)	0.1452 (9)	0.0770 (5)	−0.0216 (5)	0.0127 (4)	−0.0267 (5)
S1	0.0887 (5)	0.0493 (4)	0.0499 (3)	−0.0049 (3)	0.0256 (3)	−0.0109 (2)
O1	0.0877 (12)	0.0381 (9)	0.0631 (10)	0.0014 (7)	0.0204 (9)	0.0090 (7)
N1	0.0483 (9)	0.0386 (9)	0.0429 (9)	0.0043 (7)	0.0087 (7)	−0.0007 (7)
C1	0.0551 (12)	0.0402 (11)	0.0380 (9)	0.0020 (8)	0.0053 (8)	0.0035 (8)
C2	0.0568 (12)	0.0504 (12)	0.0358 (9)	0.0017 (9)	0.0096 (8)	0.0036 (8)
C3	0.0462 (10)	0.0394 (10)	0.0440 (10)	−0.0017 (8)	0.0047 (8)	−0.0015 (8)
C4	0.0645 (14)	0.0392 (11)	0.0653 (14)	−0.0018 (10)	0.0071 (11)	−0.0022 (10)
C5	0.092 (2)	0.0446 (13)	0.0768 (17)	−0.0206 (13)	0.0122 (15)	0.0107 (12)
C6	0.103 (2)	0.0625 (16)	0.0707 (17)	−0.0347 (15)	0.0358 (16)	−0.0021 (13)
C7	0.0701 (15)	0.0547 (14)	0.0624 (14)	−0.0176 (11)	0.0296 (12)	−0.0089 (11)
C8	0.0419 (10)	0.0409 (10)	0.0411 (9)	−0.0041 (8)	0.0049 (8)	−0.0012 (8)
C9	0.0640 (14)	0.0562 (13)	0.0488 (12)	−0.0022 (10)	0.0162 (10)	0.0012 (10)
C10	0.0605 (13)	0.0621 (14)	0.0497 (12)	−0.0031 (11)	0.0191 (10)	0.0042 (10)
C11	0.0627 (14)	0.0744 (17)	0.0567 (13)	−0.0089 (12)	0.0214 (11)	0.0065 (12)
C12	0.0582 (15)	0.097 (2)	0.0812 (19)	0.0009 (14)	0.0240 (14)	0.0061 (16)
C13	0.081 (2)	0.092 (2)	0.082 (2)	0.0075 (17)	0.0384 (17)	−0.0062 (17)
C14	0.086 (2)	0.098 (2)	0.0651 (17)	−0.0004 (17)	0.0264 (15)	−0.0181 (15)
C15	0.0638 (15)	0.094 (2)	0.0554 (14)	0.0017 (14)	0.0125 (12)	−0.0096 (13)
C16	0.0530 (12)	0.0488 (12)	0.0595 (13)	0.0125 (9)	0.0098 (10)	−0.0043 (10)
C17	0.0679 (14)	0.0395 (11)	0.0581 (13)	0.0045 (9)	0.0253 (11)	−0.0025 (9)
C18	0.099 (2)	0.0580 (15)	0.0535 (14)	−0.0054 (14)	0.0238 (14)	−0.0074 (11)

Geometric parameters (Å, º) top

Cl1—C11	1.734 (3)	C7—C8	1.393 (3)
S1—C2	1.755 (2)	C9—H9	0.9300
S1—C3	1.744 (2)	C9—C10	1.467 (3)
O1—C1	1.217 (3)	C10—C11	1.388 (4)
N1—C1	1.374 (3)	C10—C15	1.388 (4)
N1—C8	1.414 (3)	C11—C12	1.379 (4)
N1—C16	1.473 (3)	C12—H12	0.9300
C1—C2	1.492 (3)	C12—C13	1.374 (5)
C2—C9	1.331 (3)	C13—H13	0.9300
C3—C4	1.386 (3)	C13—C14	1.369 (5)
C3—C8	1.392 (3)	C14—H14	0.9300
C4—H4	0.9300	C14—C15	1.377 (4)
C4—C5	1.378 (4)	C15—H15	0.9300
C5—H5	0.9300	C16—H16A	0.9700
C5—C6	1.367 (4)	C16—H16B	0.9700
C6—H6	0.9300	C16—C17	1.459 (3)
C6—C7	1.372 (4)	C17—C18	1.177 (4)
C7—H7	0.9300	C18—H18	0.9300

C3—S1—C2	99.97 (10)	C2—C9—C10	125.5 (2)
C1—N1—C8	125.59 (17)	C10—C9—H9	117.3
C1—N1—C16	115.49 (18)	C11—C10—C9	121.1 (2)
C8—N1—C16	117.93 (17)	C11—C10—C15	116.9 (2)
O1—C1—N1	120.5 (2)	C15—C10—C9	122.0 (2)
O1—C1—C2	121.0 (2)	C10—C11—Cl1	118.8 (2)
N1—C1—C2	118.49 (18)	C12—C11—Cl1	119.1 (2)
C1—C2—S1	118.78 (16)	C12—C11—C10	122.0 (3)
C9—C2—S1	121.98 (18)	C11—C12—H12	120.3
C9—C2—C1	119.1 (2)	C13—C12—C11	119.3 (3)
C4—C3—S1	117.71 (17)	C13—C12—H12	120.3
C4—C3—C8	120.4 (2)	C12—C13—H13	119.9
C8—C3—S1	121.80 (16)	C14—C13—C12	120.2 (3)
C3—C4—H4	119.8	C14—C13—H13	119.9
C5—C4—C3	120.4 (2)	C13—C14—H14	120.0
C5—C4—H4	119.8	C13—C14—C15	120.0 (3)
C4—C5—H5	120.2	C15—C14—H14	120.0
C6—C5—C4	119.6 (2)	C10—C15—H15	119.2
C6—C5—H5	120.2	C14—C15—C10	121.6 (3)
C5—C6—H6	119.6	C14—C15—H15	119.2
C5—C6—C7	120.7 (3)	N1—C16—H16A	108.9
C7—C6—H6	119.6	N1—C16—H16B	108.9
C6—C7—H7	119.5	H16A—C16—H16B	107.7
C6—C7—C8	121.0 (2)	C17—C16—N1	113.30 (19)
C8—C7—H7	119.5	C17—C16—H16A	108.9
C3—C8—N1	121.27 (18)	C17—C16—H16B	108.9
C3—C8—C7	118.0 (2)	C18—C17—C16	178.6 (3)
C7—C8—N1	120.7 (2)	C17—C18—H18	180.0
C2—C9—H9	117.3

Cl1—C11—C12—C13	179.5 (3)	C4—C5—C6—C7	0.2 (5)
S1—C2—C9—C10	2.5 (3)	C5—C6—C7—C8	−1.2 (5)
S1—C3—C4—C5	175.4 (2)	C6—C7—C8—N1	−178.1 (3)
S1—C3—C8—N1	2.9 (3)	C6—C7—C8—C3	1.1 (4)
S1—C3—C8—C7	−176.23 (18)	C8—N1—C1—O1	168.0 (2)
O1—C1—C2—S1	157.24 (18)	C8—N1—C1—C2	−12.0 (3)
O1—C1—C2—C9	−19.0 (3)	C8—N1—C16—C17	−80.1 (3)
N1—C1—C2—S1	−22.8 (2)	C8—C3—C4—C5	−1.0 (4)
N1—C1—C2—C9	161.0 (2)	C9—C10—C11—Cl1	1.3 (3)
C1—N1—C8—C3	23.2 (3)	C9—C10—C11—C12	−178.4 (3)
C1—N1—C8—C7	−157.7 (2)	C9—C10—C15—C14	179.1 (3)
C1—N1—C16—C17	89.1 (2)	C10—C11—C12—C13	−0.8 (5)
C1—C2—C9—C10	178.7 (2)	C11—C10—C15—C14	−0.3 (4)
C2—S1—C3—C4	154.52 (19)	C11—C12—C13—C14	0.0 (5)
C2—S1—C3—C8	−29.14 (19)	C12—C13—C14—C15	0.6 (5)
C2—C9—C10—C11	126.8 (3)	C13—C14—C15—C10	−0.5 (5)
C2—C9—C10—C15	−52.6 (4)	C15—C10—C11—Cl1	−179.3 (2)
C3—S1—C2—C1	38.40 (18)	C15—C10—C11—C12	0.9 (4)
C3—S1—C2—C9	−145.5 (2)	C16—N1—C1—O1	−0.3 (3)
C3—C4—C5—C6	0.8 (4)	C16—N1—C1—C2	179.71 (18)
C4—C3—C8—N1	179.2 (2)	C16—N1—C8—C3	−168.79 (19)
C4—C3—C8—C7	0.0 (3)	C16—N1—C8—C7	10.4 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C12—H12···O1ⁱ	0.93	2.71	3.486 (4)	142
C18—H18···O1ⁱⁱ	0.93	2.33	3.191 (3)	154

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

Acknowledgements

JPJ acknowledges the NSF–MRI program (grant No. CHE-1039027) for funds to purchase the X-ray diffractometer.

References

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