Methyl 2-allyl-4-hydr­oxy-2H-1,2-benzothia­zine-3-carboxyl­ate 1,1-dioxide

Arshad, M.N.; Zia-ur-Rehman, M.; Khan, I.U.

doi:10.1107/S160053680904673X

organic compounds

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ISSN: 2056-9890

Volume 65| Part 12| December 2009| Page o3077

doi:10.1107/S160053680904673X

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Methyl 2-allyl-4-hydroxy-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide

Muhammad Nadeem Arshad,^a Muhammad Zia-ur-Rehman ^b and Islam Ullah Khan ^a ^*

^aDepartment of Chemistry, Government College University, Lahore 54000, Pakistan, and ^bApplied Chemistry Research Centre, PCSIR Laboratories Complex, Ferozpure Road, Lahore 54600, Pakistan
^*Correspondence e-mail: iukhan.gcu@gmail.com

(Received 3 November 2009; accepted 5 November 2009; online 14 November 2009)

In the title compound, C₁₃H₁₃NO₅S, the thiazine ring adopts a distorted half-chair conformation. Intramolecular O—H⋯O and C—H⋯O hydrogen bonds give rise to two six-membered hydrogen bonded rings. In the crystal, molecules are linked through weak intermolecular C—H⋯O hydrogen bonds, resulting in a zigzag chain lying along the c axis.

Related literature

For the syntheses of related compounds, see: Braun (1923 ); Zia-ur-Rehman et al. (2005 ). For the biological activity of benzothiazines, see: Zia-ur-Rehman et al. (2006 , 2009 ). For related structures, see: Arshad et al. (2009 ); Fabiola et al. (1998 ); Zia-ur-Rehman et al. (2007 ).

Experimental

Crystal data

C₁₃H₁₃NO₅S
M_r = 295.30
Orthorhombic, P c a 2₁
a = 12.4289 (10) Å
b = 8.3706 (8) Å
c = 13.0132 (11) Å
V = 1353.9 (2) Å³
Z = 4
Mo Kα radiation
μ = 0.26 mm⁻¹
T = 296 K
0.45 × 0.11 × 0.07 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.893, T_max = 0.982
8404 measured reflections
2808 independent reflections
1763 reflections with I > 2σ(I)
R_int = 0.044

Refinement

R[F² > 2σ(F²)] = 0.057
wR(F²) = 0.103
S = 1.06
2808 reflections
183 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.18 e Å⁻³
Δρ_min = −0.23 e Å⁻³
Absolute structure: Flack (1983 ), 1046 Friedel pairs
Flack parameter: 0.07 (11)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3O⋯O4	0.82	1.84	2.555 (4)	146
C11—H11A⋯O5	0.97	2.50	3.055 (4)	116
C3—H3A⋯O1ⁱ	0.93	2.51	3.406 (6)	163
Symmetry code: (i) $[-x-{\script{1\over 2}}, y, z-{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009 ) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ) and PLATON.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053680904673X/is2483sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053680904673X/is2483Isup2.hkl

checkCIF report

Comment top

Benzothiazine1,1-dioxides are familiar for their different type of biological activities (Zia-ur-Rehman et al., 2006) and have been synthesized continuously since the very first synthesis in 1923 (Braun, 1923). In continuation of our work on he synthesis of various bioactive benzothiazines (Zia-ur-Rehman et al., 2005, 2009), we herein report the crystal structure of the title compound (I), thiazine ring exhibits a distorted half-chair conformation with S1/C1/C6/C7 atoms lying in a plane and N1 showing significant departure from the plane due to its pyramidal geometry projecting the allyl group approximately perpendicular to the ring (Fig. 1). Like previously reported crystal structures of various 1,2-benzothiazine 1,1-dioxide derivatives (Arshad et al., 2009; Fabiola et al., 1998; Zia-ur-Rehman et al., 2007), the enolic hydrogen on O3 is involved in intramolecular hydrogen bonding (Table1). In addition, C11—H11A···O5 hydrogen bond gives rise to another six-membered hydrogen ring in the molecule while C7—C8 bond length [1.338 (5) Å] (very close to normal C—C bond; 1.36 Å) indicates a partial double-bond character indicating the dominance of enolic form in the molecule. The C1—S1 bond distance [1.746 (4) Å] is as expected for typical C(sp2)—S bond (1.751 Å). Each molecule is linked to neighbouring molecules via weak C—H···O=S interactions giving rise to zigzag chains along the c axis (Fig. 2).

Related literature top

For the syntheses of related compounds, see: Braun (1923); Zia-ur-Rehman et al. (2005). For the biological activity of benzothiazines, see: Zia-ur-Rehman et al. (2006, 2009). For related structures, see: Arshad et al. (2009); Fabiola et al. (1998); Zia-ur-Rehman et al. (2007).

Experimental top

Allyl iodide (5.04 g, 30.0 mmol) was added drop wise to the mixture of methyl 4-hydroxy-2H-1,2-benzothiazine-3-carboxylate-1,1-dioxide (3.83 g, 15.0 mmol), anhydrous potassium carbonate (1.68 g, 30.0 mmol) and dimethylformamide (20 ml) in a round bottom flask. Contents were stirred at room temperature for 7 h under nitrogen atmosphere and poured over ice cooled water (300 ml) resulting in an immediate formation of a white solid, which was filtered and washed with cold water. Single crystals were obtained by re-crystallization from a methanol solution

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009) and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of (I), with displacement ellipsoids at the 50% probability level.
	Fig. 2. Perspective view of the crystal packing showing O—H···O and C—H···O hydrogen-bonded interactions (dashed lines). H atoms not involved in hydrogen bonding have been omitted for clarity.

Methyl 2-allyl-4-hydroxy-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide top

Crystal data top

C₁₃H₁₃NO₅S	F(000) = 616
M_r = 295.30	D_x = 1.449 Mg m⁻³
Orthorhombic, Pca2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2ac	Cell parameters from 1619 reflections
a = 12.4289 (10) Å	θ = 3.1–21.7°
b = 8.3706 (8) Å	µ = 0.26 mm⁻¹
c = 13.0132 (11) Å	T = 296 K
V = 1353.9 (2) Å³	Needle, colourless
Z = 4	0.45 × 0.11 × 0.07 mm

Data collection top

Bruker APEXII CCD area-detector diffractometer	2808 independent reflections
Radiation source: fine-focus sealed tube	1763 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.044
ϕ and ω scans	θ_max = 28.3°, θ_min = 2.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −16→16
T_min = 0.893, T_max = 0.982	k = −11→10
8404 measured reflections	l = −17→9

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.057	H-atom parameters constrained
wR(F²) = 0.103	w = 1/[σ²(F_o²) + (0.0381P)² + 0.1044P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max < 0.001
2808 reflections	Δρ_max = 0.18 e Å⁻³
183 parameters	Δρ_min = −0.23 e Å⁻³
1 restraint	Absolute structure: Flack (1983), 1046 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.07 (11)

Crystal data top

C₁₃H₁₃NO₅S	V = 1353.9 (2) Å³
M_r = 295.30	Z = 4
Orthorhombic, Pca2₁	Mo Kα radiation
a = 12.4289 (10) Å	µ = 0.26 mm⁻¹
b = 8.3706 (8) Å	T = 296 K
c = 13.0132 (11) Å	0.45 × 0.11 × 0.07 mm

Data collection top

Bruker APEXII CCD area-detector diffractometer	2808 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	1763 reflections with I > 2σ(I)
T_min = 0.893, T_max = 0.982	R_int = 0.044
8404 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.057	H-atom parameters constrained
wR(F²) = 0.103	Δρ_max = 0.18 e Å⁻³
S = 1.06	Δρ_min = −0.23 e Å⁻³
2808 reflections	Absolute structure: Flack (1983), 1046 Friedel pairs
183 parameters	Absolute structure parameter: 0.07 (11)
1 restraint

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s 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 > σ(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
S1	−0.11229 (6)	0.28643 (12)	0.49624 (9)	0.0550 (3)
O1	−0.12270 (18)	0.1530 (4)	0.5634 (3)	0.0733 (9)
O2	−0.19486 (15)	0.4041 (3)	0.4937 (3)	0.0714 (8)
O3	0.18469 (19)	0.0795 (3)	0.4129 (2)	0.0669 (9)
H3O	0.2303	0.0963	0.4571	0.100*
O4	0.26461 (18)	0.2122 (3)	0.5724 (2)	0.0658 (8)
O5	0.16238 (19)	0.3843 (3)	0.6600 (2)	0.0612 (7)
N1	0.0004 (2)	0.3754 (3)	0.5229 (2)	0.0490 (9)
C1	−0.0885 (3)	0.2109 (4)	0.3733 (3)	0.0487 (10)
C2	−0.1708 (3)	0.1997 (5)	0.3013 (4)	0.0647 (12)
H2	−0.2396	0.2360	0.3168	0.078*
C3	−0.1488 (4)	0.1344 (5)	0.2074 (4)	0.0737 (13)
H3A	−0.2034	0.1247	0.1590	0.088*
C4	−0.0462 (4)	0.0828 (5)	0.1837 (4)	0.0721 (12)
H4	−0.0319	0.0406	0.1191	0.087*
C5	0.0348 (3)	0.0935 (5)	0.2553 (3)	0.0602 (12)
H5	0.1032	0.0564	0.2391	0.072*
C6	0.0156 (3)	0.1588 (4)	0.3509 (3)	0.0468 (9)
C7	0.1002 (3)	0.1766 (4)	0.4281 (3)	0.0467 (9)
C8	0.0945 (2)	0.2785 (4)	0.5071 (4)	0.0450 (9)
C9	0.1819 (3)	0.2889 (4)	0.5819 (3)	0.0502 (9)
C10	0.2475 (4)	0.3995 (6)	0.7344 (4)	0.0867 (14)
H10A	0.3070	0.4555	0.7042	0.130*
H10B	0.2706	0.2951	0.7557	0.130*
H10C	0.2218	0.4579	0.7930	0.130*
C11	0.0106 (3)	0.5495 (4)	0.5090 (3)	0.0595 (10)
H11A	0.0695	0.5878	0.5513	0.071*
H11B	−0.0548	0.6004	0.5331	0.071*
C12	0.0304 (4)	0.5986 (7)	0.4006 (5)	0.1008 (19)
H12	0.0732	0.5271	0.3642	0.121*
C13	0.0036 (6)	0.7061 (11)	0.3530 (7)	0.161 (3)
H13A	−0.0395	0.7845	0.3826	0.194*
H13B	0.0249	0.7154	0.2848	0.194*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0376 (4)	0.0683 (6)	0.0593 (6)	0.0050 (4)	0.0069 (5)	0.0078 (7)
O1	0.0553 (15)	0.088 (2)	0.076 (2)	−0.0060 (14)	0.0169 (15)	0.0296 (19)
O2	0.0418 (12)	0.0919 (19)	0.080 (2)	0.0220 (12)	0.0017 (16)	−0.0075 (19)
O3	0.0477 (15)	0.0674 (19)	0.086 (3)	0.0147 (14)	−0.0021 (13)	−0.0186 (15)
O4	0.0474 (14)	0.0682 (17)	0.082 (2)	0.0146 (13)	−0.0103 (13)	−0.0130 (18)
O5	0.0537 (14)	0.0741 (19)	0.0557 (19)	0.0121 (13)	−0.0078 (13)	−0.0097 (16)
N1	0.0439 (14)	0.0501 (18)	0.053 (3)	0.0077 (13)	0.0021 (12)	0.0005 (16)
C1	0.046 (2)	0.037 (2)	0.064 (3)	−0.0039 (16)	−0.0024 (18)	0.006 (2)
C2	0.055 (2)	0.055 (3)	0.084 (4)	0.005 (2)	−0.012 (2)	−0.001 (3)
C3	0.074 (3)	0.072 (3)	0.075 (4)	0.001 (2)	−0.025 (2)	−0.010 (3)
C4	0.092 (3)	0.064 (3)	0.060 (3)	−0.005 (2)	−0.011 (3)	−0.016 (2)
C5	0.057 (2)	0.052 (3)	0.072 (4)	−0.0030 (18)	0.001 (2)	−0.013 (2)
C6	0.0473 (19)	0.039 (2)	0.054 (3)	−0.0024 (15)	−0.0026 (18)	−0.0014 (19)
C7	0.0384 (18)	0.043 (2)	0.059 (3)	0.0018 (15)	0.0066 (18)	0.0058 (19)
C8	0.0376 (15)	0.0445 (19)	0.053 (3)	0.0037 (15)	0.005 (2)	0.001 (2)
C9	0.048 (2)	0.046 (2)	0.057 (3)	0.0034 (18)	0.0015 (19)	0.005 (2)
C10	0.077 (2)	0.113 (4)	0.070 (3)	0.024 (3)	−0.031 (2)	−0.027 (3)
C11	0.061 (2)	0.050 (2)	0.068 (3)	0.0065 (17)	−0.002 (2)	0.001 (2)
C12	0.093 (4)	0.070 (4)	0.139 (6)	0.008 (3)	0.010 (3)	0.036 (4)
C13	0.211 (9)	0.131 (7)	0.142 (7)	−0.031 (6)	−0.035 (6)	0.050 (5)

Geometric parameters (Å, º) top

S1—O2	1.423 (2)	C4—C5	1.375 (5)
S1—O1	1.424 (3)	C4—H4	0.9300
S1—N1	1.625 (3)	C5—C6	1.380 (5)
S1—C1	1.746 (4)	C5—H5	0.9300
O3—C7	1.343 (4)	C6—C7	1.462 (5)
O3—H3O	0.8200	C7—C8	1.338 (5)
O4—C9	1.218 (4)	C8—C9	1.461 (5)
O5—C9	1.315 (4)	C10—H10A	0.9600
O5—C10	1.440 (5)	C10—H10B	0.9600
N1—C8	1.438 (4)	C10—H10C	0.9600
N1—C11	1.473 (4)	C11—C12	1.490 (7)
C1—C2	1.390 (5)	C11—H11A	0.9700
C1—C6	1.396 (5)	C11—H11B	0.9700
C2—C3	1.366 (6)	C12—C13	1.142 (8)
C2—H2	0.9300	C12—H12	0.9300
C3—C4	1.380 (6)	C13—H13A	0.9300
C3—H3A	0.9300	C13—H13B	0.9300

O2—S1—O1	119.46 (17)	C1—C6—C7	119.4 (3)
O2—S1—N1	108.03 (15)	C8—C7—O3	122.7 (3)
O1—S1—N1	107.87 (16)	C8—C7—C6	123.7 (3)
O2—S1—C1	110.57 (18)	O3—C7—C6	113.5 (3)
O1—S1—C1	107.1 (2)	C7—C8—N1	120.8 (3)
N1—S1—C1	102.48 (15)	C7—C8—C9	120.7 (3)
C7—O3—H3O	109.5	N1—C8—C9	118.4 (3)
C9—O5—C10	116.0 (3)	O4—C9—O5	123.6 (3)
C8—N1—C11	118.1 (3)	O4—C9—C8	121.9 (4)
C8—N1—S1	114.3 (2)	O5—C9—C8	114.4 (3)
C11—N1—S1	120.1 (2)	O5—C10—H10A	109.5
C2—C1—C6	121.4 (4)	O5—C10—H10B	109.5
C2—C1—S1	121.2 (3)	H10A—C10—H10B	109.5
C6—C1—S1	117.5 (3)	O5—C10—H10C	109.5
C3—C2—C1	118.8 (4)	H10A—C10—H10C	109.5
C3—C2—H2	120.6	H10B—C10—H10C	109.5
C1—C2—H2	120.6	N1—C11—C12	113.8 (4)
C2—C3—C4	120.7 (4)	N1—C11—H11A	108.8
C2—C3—H3A	119.7	C12—C11—H11A	108.8
C4—C3—H3A	119.7	N1—C11—H11B	108.8
C5—C4—C3	120.3 (4)	C12—C11—H11B	108.8
C5—C4—H4	119.9	H11A—C11—H11B	107.7
C3—C4—H4	119.9	C13—C12—C11	133.1 (7)
C4—C5—C6	120.7 (4)	C13—C12—H12	113.5
C4—C5—H5	119.7	C11—C12—H12	113.5
C6—C5—H5	119.7	C12—C13—H13A	120.0
C5—C6—C1	118.1 (3)	C12—C13—H13B	120.0
C5—C6—C7	122.4 (3)	H13A—C13—H13B	120.0

O2—S1—N1—C8	−167.6 (2)	S1—C1—C6—C7	−2.9 (5)
O1—S1—N1—C8	62.0 (3)	C5—C6—C7—C8	159.4 (4)
C1—S1—N1—C8	−50.8 (3)	C1—C6—C7—C8	−19.9 (6)
O2—S1—N1—C11	−18.4 (4)	C5—C6—C7—O3	−21.1 (5)
O1—S1—N1—C11	−148.8 (3)	C1—C6—C7—O3	159.6 (3)
C1—S1—N1—C11	98.4 (3)	O3—C7—C8—N1	−177.3 (3)
O2—S1—C1—C2	−31.7 (4)	C6—C7—C8—N1	2.2 (6)
O1—S1—C1—C2	100.0 (3)	O3—C7—C8—C9	0.0 (6)
N1—S1—C1—C2	−146.6 (3)	C6—C7—C8—C9	179.5 (3)
O2—S1—C1—C6	149.8 (3)	C11—N1—C8—C7	−112.6 (4)
O1—S1—C1—C6	−78.6 (3)	S1—N1—C8—C7	37.3 (4)
N1—S1—C1—C6	34.8 (3)	C11—N1—C8—C9	70.1 (4)
C6—C1—C2—C3	0.8 (6)	S1—N1—C8—C9	−140.1 (3)
S1—C1—C2—C3	−177.7 (3)	C10—O5—C9—O4	2.4 (5)
C1—C2—C3—C4	−1.0 (6)	C10—O5—C9—C8	−179.0 (3)
C2—C3—C4—C5	1.3 (7)	C7—C8—C9—O4	3.8 (6)
C3—C4—C5—C6	−1.3 (6)	N1—C8—C9—O4	−178.8 (3)
C4—C5—C6—C1	1.1 (6)	C7—C8—C9—O5	−174.8 (3)
C4—C5—C6—C7	−178.2 (4)	N1—C8—C9—O5	2.6 (5)
C2—C1—C6—C5	−0.8 (6)	C8—N1—C11—C12	68.0 (4)
S1—C1—C6—C5	177.7 (3)	S1—N1—C11—C12	−80.1 (4)
C2—C1—C6—C7	178.5 (3)	N1—C11—C12—C13	144.7 (8)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3O···O4	0.82	1.84	2.555 (4)	146
C11—H11A···O5	0.97	2.50	3.055 (4)	116
C3—H3A···O1ⁱ	0.93	2.51	3.406 (6)	163

Symmetry code: (i) −x−1/2, y, z−1/2.

Experimental details

Crystal data
Chemical formula	C₁₃H₁₃NO₅S
M_r	295.30
Crystal system, space group	Orthorhombic, Pca2₁
Temperature (K)	296
a, b, c (Å)	12.4289 (10), 8.3706 (8), 13.0132 (11)
V (Å³)	1353.9 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.26
Crystal size (mm)	0.45 × 0.11 × 0.07

Data collection
Diffractometer	Bruker APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.893, 0.982
No. of measured, independent and observed [I > 2σ(I)] reflections	8404, 2808, 1763
R_int	0.044
(sin θ/λ)_max (Å⁻¹)	0.668

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.057, 0.103, 1.06
No. of reflections	2808
No. of parameters	183
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.18, −0.23
Absolute structure	Flack (1983), 1046 Friedel pairs
Absolute structure parameter	0.07 (11)

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and Mercury (Macrae et al., 2006), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3O···O4	0.82	1.84	2.555 (4)	146
C11—H11A···O5	0.97	2.50	3.055 (4)	116
C3—H3A···O1ⁱ	0.93	2.51	3.406 (6)	163

Symmetry code: (i) −x−1/2, y, z−1/2.

Acknowledgements

The authors are grateful to the Higher Education Commission for a grant to purchase the diffractometer and PCSIR laboratories complex, Lahore for providing necessary chemicals and laboratory facilities.

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