Methyl 3-oxo-2,3-dihydro-1,2-benzothia­zole-2-acetate 1,1-dioxide

Siddiqui, W.A.; Ahmad, S.; Siddiqui, H.L.; Parvez, M.; Rashid, R.

doi:10.1107/S1600536808009951

organic compounds

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ISSN: 2056-9890

Volume 64| Part 5| May 2008| Page o859

doi:10.1107/S1600536808009951

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Methyl 3-oxo-2,3-dihydro-1,2-benzothiazole-2-acetate 1,1-dioxide

Waseeq Ahmad Siddiqui,^a ^* Saeed Ahmad,^b Hamid Latif Siddiqui,^c Masood Parvez ^d and Rehana Rashid ^e

^aDepartment of Chemistry, University of Sargodha, Sargodha, Pakistan, ^bDepartment of Chemistry, University of Science and Technology, Bannu, Pakistan, ^cInstitute of Chemistry, University of the Punjab, Lahore, Pakistan, ^dDepartment of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4, and ^eDepartment of Chemistry, University of Balochistan, Quetta, Pakistan
^*Correspondence e-mail: waseeq_786@yahoo.com

(Received 19 March 2008; accepted 11 April 2008; online 16 April 2008)

The title molecule, C₁₀H₉NO₅S, is composed of two essentially planar units with a dihedral angle of 89.16 (6)° between them. In the crystal structure, there are weak intermolecular C—H⋯O interactions resulting in dimeric pairs of molecules about inversion centres and chains of molecules extended along the a and c axes, thus stabilizing the structure. In addition, benzothiazole rings lying parallel to each other with centroid–centroid distances of 3.679 (2) and 3.999 (2) Å indicate the existence of π–π stacking interactions.

Related literature

For related literature, see: Kapui et al. (2003 ); Masashi et al. (1999 ); Manjarrez et al. (1996 ); Siddiqui, Ahmad, Khan, Siddiqui & Parvez (2007 ); Siddiqui, Ahmad, Khan, Siddiqui & Weaver (2007 ); Siddiqui, Ahmad, Siddiqui et al. (2007 ); Siddiqui et al. (2008 ); Xu et al. (2005 , 2006 ).

Experimental

Crystal data

C₁₀H₉NO₅S
M_r = 255.24
Triclinic, $[P \overline 1]$
a = 7.765 (3) Å
b = 8.496 (3) Å
c = 8.776 (4) Å
α = 104.39 (2)°
β = 100.58 (2)°
γ = 94.30 (2)°
V = 546.8 (4) Å³
Z = 2
Mo Kα radiation
μ = 0.30 mm⁻¹
T = 173 (2) K
0.16 × 0.10 × 0.08 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SORTAV; Blessing, 1997 ) T_min = 0.953, T_max = 0.976
4654 measured reflections
2468 independent reflections
2040 reflections with I > 2σ(I)
R_int = 0.024

Refinement

R[F² > 2σ(F²)] = 0.040
wR(F²) = 0.111
S = 1.03
2468 reflections
155 parameters
H-atom parameters constrained
Δρ_max = 0.46 e Å⁻³
Δρ_min = −0.43 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯O5ⁱ	0.95	2.53	3.435 (3)	160
C4—H4⋯O4ⁱⁱ	0.95	2.54	3.209 (3)	128
C8—H8A⋯O2ⁱⁱⁱ	0.99	2.49	3.435 (3)	159
C10—H10C⋯O1^iv	0.98	2.47	3.431 (3)	167
Symmetry codes: (i) x, y, z+1; (ii) -x, -y, -z+2; (iii) -x+1, -y+1, -z+2; (iv) x+1, y, z.

Data collection: COLLECT (Hooft, 1998 ); cell refinement: DENZO (Otwinowski & Minor, 1997 ); data reduction: SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SAPI91 (Fan, 1991 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808009951/lh2607sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808009951/lh2607Isup2.hkl

checkCIF report

Comment top

Saccharin derivatives are considered to be the most potent orally active human leucocyte elastase (HLE) inhibitors for the treatment of chronic obstructive pulmonary disease (COPD), acute respiratory distress syndrome (ARDS), cystic fibrosis, asthma and other inflammatory diseases (Kapui et al., 2003). Various biologically important saccharin skeletons and their N-alkyl derivatives were efficiently prepared (Xu et al., 2006) by chromium oxide-catalyzed oxidation of N-alkyl(o-methyl)arenesulfonamides in acetonitrile besides the already developed methodology utilizing irradiation techniques for similar type of conversions (Masashi et al., 1999). In continuation to our research on benzene, 1,2-benzothiazine 1,1-dioxide and saccharin derivatives (Siddiqui et al., 2008; Siddiqui, Ahmad, Khan, Siddiqui & Weaver, 2007), we report herein the crystal structure of the title compound, (I).

The structure of (I) is composed of an essentially planar moiety, S1/N1/O1/C1—C7 with maximum deviations from the least-square planes being: O1 = -0.0540 (12) and N1 = 0.0540 (13) Å, and an approximately planar moiety C8—C10/O4/O5 with maximum deviation of 0.0766 (13) Å for C8. The two moieties are oriented with a dihedral angle of 89.16 (6)° between their least-squares planes. The structure is stabilized by four rather weak intermolecular interactions of the type C—H···O (Fig. 2 and Table 1). Of these interactions, C4—H4···O5 and C8—H8A···O2 H-bonds result in dimeric pairs of (I) while C10—H10···O1 and C2—H2···O5 result in chains of molecules extended along the a- and c-axes, respectively. The benzothiazole rings in (I) lie parallel to each other about the origin with the shortest distance between the centroids of the benzene rings of the adjacent molecules is 3.679 (2) Å which indicates the existence of π-π stacking interactions. The thiazoline rings located about inversion centers in the middle of the b axis (at 0, 1/2, 0) also show π-π interaction with centroids of these rings separated by 3.999 (2) Å (Fig. 3). The molecular dimensions in (I) are in agreement with the corresponding dimensions reported in similar structures (Xu et al., 2005; Siddiqui, Ahmad, Khan, Siddiqui & Parvez, 2007; Siddiqui, Ahmad, Siddiqui et al., 2007; Siddiqui et al., 2008).

Related literature top

For related literature, see: Kapui et al. (2003); Masashi et al. (1999); Manjarrez et al. (1996); Siddiqui, Ahmad, Khan, Siddiqui & Parvez (2007); Siddiqui, Ahmad, Khan, Siddiqui & Weaver (2007); Siddiqui, Ahmad, Siddiqui et al. (2007); Siddiqui et al. (2008); Xu et al. (2005, 2006).

Experimental top

The compound (I) was prepared following the prcedures reported earlier (Manjarrez et al., 1996). Crystals suitable for X-ray crystallography were grown from a solution of CH₃OH by slow evaporation at 313 K.

Computing details top

Data collection: COLLECT (Hooft, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997); data reduction: SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SAPI91 (Fan, 1991); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. ORTEP-3 (Farrugia, 1997) drawing of (I) with displacement ellipsoids plotted at 50% probability level.
	Fig. 2. Unit cell packing of (I) showing C—H···O interactions represented by dashed lines; H-atoms not involved in H-bonds have been omitted.
	Fig. 3. Unit cell packing of (I) showing π-π stacking interactions represented by dashed lines; H-atoms have been omitted for clarity.

Methyl 3-oxo-2,3-dihydro-1,2-benzothiazole-2-acetate 1,1-dioxide top

Crystal data top

C₁₀H₉NO₅S	Z = 2
M_r = 255.24	F(000) = 264
Triclinic, P1	D_x = 1.550 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.765 (3) Å	Cell parameters from 4654 reflections
b = 8.496 (3) Å	θ = 3.9–27.4°
c = 8.776 (4) Å	µ = 0.31 mm⁻¹
α = 104.39 (2)°	T = 173 K
β = 100.58 (2)°	Block, colourless
γ = 94.30 (2)°	0.16 × 0.10 × 0.08 mm
V = 546.8 (4) Å³

Data collection top

Nonius KappaCCD diffractometer	2468 independent reflections
Radiation source: fine-focus sealed tube	2040 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.024
ω and ϕ scans	θ_max = 27.4°, θ_min = 3.9°
Absorption correction: multi-scan (SORTAV; Blessing, 1997)	h = −10→9
T_min = 0.953, T_max = 0.976	k = −11→10
4654 measured reflections	l = −11→11

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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.111	H-atom parameters constrained
S = 1.03	w = 1/[σ²(F_o²) + (0.056P)² + 0.29P] where P = (F_o² + 2F_c²)/3
2468 reflections	(Δ/σ)_max < 0.001
155 parameters	Δρ_max = 0.46 e Å⁻³
0 restraints	Δρ_min = −0.43 e Å⁻³

Crystal data top

C₁₀H₉NO₅S	γ = 94.30 (2)°
M_r = 255.24	V = 546.8 (4) Å³
Triclinic, P1	Z = 2
a = 7.765 (3) Å	Mo Kα radiation
b = 8.496 (3) Å	µ = 0.31 mm⁻¹
c = 8.776 (4) Å	T = 173 K
α = 104.39 (2)°	0.16 × 0.10 × 0.08 mm
β = 100.58 (2)°

Data collection top

Nonius KappaCCD diffractometer	2468 independent reflections
Absorption correction: multi-scan (SORTAV; Blessing, 1997)	2040 reflections with I > 2σ(I)
T_min = 0.953, T_max = 0.976	R_int = 0.024
4654 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.040	0 restraints
wR(F²) = 0.111	H-atom parameters constrained
S = 1.03	Δρ_max = 0.46 e Å⁻³
2468 reflections	Δρ_min = −0.43 e Å⁻³
155 parameters

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	0.25284 (6)	0.37128 (6)	1.06522 (6)	0.02602 (16)
O1	−0.07412 (18)	0.18372 (19)	0.67891 (17)	0.0354 (3)
O2	0.40672 (17)	0.29152 (17)	1.08988 (17)	0.0320 (3)
O3	0.2727 (2)	0.54422 (17)	1.13620 (18)	0.0372 (4)
O4	0.3882 (2)	0.14876 (17)	0.70088 (18)	0.0369 (4)
O5	0.41016 (18)	0.33528 (17)	0.56027 (16)	0.0312 (3)
N1	0.1635 (2)	0.3311 (2)	0.87005 (18)	0.0275 (4)
C1	0.0687 (2)	0.2676 (2)	1.1032 (2)	0.0243 (4)
C2	0.0451 (3)	0.2516 (2)	1.2517 (2)	0.0303 (4)
H2	0.1321	0.2987	1.3471	0.036*
C3	−0.1118 (3)	0.1633 (3)	1.2543 (3)	0.0325 (4)
H3	−0.1321	0.1482	1.3535	0.039*
C4	−0.2397 (3)	0.0968 (2)	1.1148 (3)	0.0329 (5)
H4	−0.3467	0.0384	1.1202	0.040*
C5	−0.2128 (3)	0.1147 (2)	0.9669 (2)	0.0297 (4)
H5	−0.3005	0.0698	0.8716	0.036*
C6	−0.0558 (2)	0.1990 (2)	0.9619 (2)	0.0245 (4)
C7	−0.0003 (2)	0.2326 (2)	0.8179 (2)	0.0263 (4)
C8	0.2499 (3)	0.3960 (2)	0.7616 (2)	0.0292 (4)
H8A	0.3291	0.4972	0.8238	0.035*
H8B	0.1593	0.4256	0.6819	0.035*
C9	0.3566 (2)	0.2757 (2)	0.6733 (2)	0.0268 (4)
C10	0.5248 (3)	0.2391 (3)	0.4726 (3)	0.0435 (6)
H10A	0.5553	0.2910	0.3914	0.052*
H10B	0.4638	0.1284	0.4195	0.052*
H10C	0.6329	0.2329	0.5475	0.052*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0241 (3)	0.0292 (3)	0.0245 (3)	0.00447 (18)	0.00385 (18)	0.00737 (18)
O1	0.0311 (7)	0.0495 (9)	0.0236 (7)	0.0080 (6)	0.0024 (6)	0.0076 (6)
O2	0.0225 (7)	0.0398 (8)	0.0339 (8)	0.0068 (6)	0.0027 (6)	0.0117 (6)
O3	0.0426 (9)	0.0266 (7)	0.0379 (8)	0.0026 (6)	0.0035 (7)	0.0045 (6)
O4	0.0472 (9)	0.0316 (8)	0.0378 (8)	0.0101 (7)	0.0158 (7)	0.0136 (6)
O5	0.0308 (7)	0.0441 (8)	0.0252 (7)	0.0126 (6)	0.0102 (6)	0.0158 (6)
N1	0.0242 (8)	0.0376 (9)	0.0217 (8)	0.0022 (7)	0.0048 (6)	0.0102 (7)
C1	0.0226 (9)	0.0270 (9)	0.0251 (9)	0.0069 (7)	0.0061 (7)	0.0083 (7)
C2	0.0307 (10)	0.0375 (11)	0.0241 (10)	0.0094 (8)	0.0053 (8)	0.0095 (8)
C3	0.0377 (11)	0.0375 (11)	0.0309 (11)	0.0155 (9)	0.0161 (9)	0.0151 (8)
C4	0.0269 (10)	0.0328 (10)	0.0452 (12)	0.0065 (8)	0.0137 (9)	0.0164 (9)
C5	0.0245 (9)	0.0314 (10)	0.0328 (10)	0.0046 (8)	0.0035 (8)	0.0095 (8)
C6	0.0252 (9)	0.0248 (9)	0.0240 (9)	0.0086 (7)	0.0042 (7)	0.0066 (7)
C7	0.0261 (9)	0.0288 (9)	0.0237 (10)	0.0051 (7)	0.0073 (7)	0.0042 (7)
C8	0.0305 (10)	0.0329 (10)	0.0297 (10)	0.0075 (8)	0.0115 (8)	0.0135 (8)
C9	0.0230 (9)	0.0325 (10)	0.0243 (9)	0.0000 (7)	0.0032 (7)	0.0090 (8)
C10	0.0436 (13)	0.0656 (15)	0.0302 (11)	0.0250 (11)	0.0173 (10)	0.0169 (10)

Geometric parameters (Å, º) top

S1—O2	1.4258 (15)	C3—C4	1.389 (3)
S1—O3	1.4306 (15)	C3—H3	0.9500
S1—N1	1.6640 (18)	C4—C5	1.395 (3)
S1—C1	1.7504 (19)	C4—H4	0.9500
O1—C7	1.202 (2)	C5—C6	1.380 (3)
O4—C9	1.196 (2)	C5—H5	0.9500
O5—C9	1.335 (2)	C6—C7	1.492 (3)
O5—C10	1.449 (2)	C8—C9	1.517 (3)
N1—C7	1.402 (3)	C8—H8A	0.9900
N1—C8	1.449 (2)	C8—H8B	0.9900
C1—C2	1.387 (3)	C10—H10A	0.9800
C1—C6	1.388 (3)	C10—H10B	0.9800
C2—C3	1.389 (3)	C10—H10C	0.9800
C2—H2	0.9500

O2—S1—O3	116.71 (9)	C6—C5—H5	120.7
O2—S1—N1	110.73 (9)	C4—C5—H5	120.7
O3—S1—N1	109.35 (9)	C5—C6—C1	119.81 (18)
O2—S1—C1	112.26 (9)	C5—C6—C7	127.38 (17)
O3—S1—C1	112.83 (9)	C1—C6—C7	112.78 (17)
N1—S1—C1	92.26 (9)	O1—C7—N1	123.33 (18)
C9—O5—C10	115.33 (16)	O1—C7—C6	128.71 (18)
C7—N1—C8	122.31 (16)	N1—C7—C6	107.93 (16)
C7—N1—S1	116.00 (13)	N1—C8—C9	112.82 (16)
C8—N1—S1	121.68 (13)	N1—C8—H8A	109.0
C2—C1—C6	122.73 (18)	C9—C8—H8A	109.0
C2—C1—S1	126.37 (15)	N1—C8—H8B	109.0
C6—C1—S1	110.90 (14)	C9—C8—H8B	109.0
C1—C2—C3	116.80 (19)	H8A—C8—H8B	107.8
C1—C2—H2	121.6	O4—C9—O5	125.61 (18)
C3—C2—H2	121.6	O4—C9—C8	125.59 (18)
C2—C3—C4	121.34 (19)	O5—C9—C8	108.80 (16)
C2—C3—H3	119.3	O5—C10—H10A	109.5
C4—C3—H3	119.3	O5—C10—H10B	109.5
C3—C4—C5	120.73 (19)	H10A—C10—H10B	109.5
C3—C4—H4	119.6	O5—C10—H10C	109.5
C5—C4—H4	119.6	H10A—C10—H10C	109.5
C6—C5—C4	118.57 (18)	H10B—C10—H10C	109.5

O2—S1—N1—C7	111.37 (15)	C2—C1—C6—C5	1.8 (3)
O3—S1—N1—C7	−118.66 (15)	S1—C1—C6—C5	−178.65 (14)
C1—S1—N1—C7	−3.48 (15)	C2—C1—C6—C7	−179.84 (17)
O2—S1—N1—C8	−69.24 (17)	S1—C1—C6—C7	−0.3 (2)
O3—S1—N1—C8	60.73 (17)	C8—N1—C7—O1	6.2 (3)
C1—S1—N1—C8	175.91 (15)	S1—N1—C7—O1	−174.37 (15)
O2—S1—C1—C2	68.07 (19)	C8—N1—C7—C6	−175.64 (16)
O3—S1—C1—C2	−66.31 (19)	S1—N1—C7—C6	3.7 (2)
N1—S1—C1—C2	−178.43 (18)	C5—C6—C7—O1	−5.9 (3)
O2—S1—C1—C6	−111.44 (14)	C1—C6—C7—O1	175.94 (19)
O3—S1—C1—C6	114.19 (14)	C5—C6—C7—N1	176.14 (18)
N1—S1—C1—C6	2.07 (14)	C1—C6—C7—N1	−2.0 (2)
C6—C1—C2—C3	−0.4 (3)	C7—N1—C8—C9	−84.4 (2)
S1—C1—C2—C3	−179.86 (15)	S1—N1—C8—C9	96.29 (18)
C1—C2—C3—C4	−1.0 (3)	C10—O5—C9—O4	−3.8 (3)
C2—C3—C4—C5	1.0 (3)	C10—O5—C9—C8	175.82 (16)
C3—C4—C5—C6	0.4 (3)	N1—C8—C9—O4	−9.1 (3)
C4—C5—C6—C1	−1.8 (3)	N1—C8—C9—O5	171.21 (15)
C4—C5—C6—C7	−179.84 (17)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O5ⁱ	0.95	2.53	3.435 (3)	160
C4—H4···O4ⁱⁱ	0.95	2.54	3.209 (3)	128
C8—H8A···O2ⁱⁱⁱ	0.99	2.49	3.435 (3)	159
C10—H10C···O1^iv	0.98	2.47	3.431 (3)	167

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

Experimental details

Crystal data
Chemical formula	C₁₀H₉NO₅S
M_r	255.24
Crystal system, space group	Triclinic, P1
Temperature (K)	173
a, b, c (Å)	7.765 (3), 8.496 (3), 8.776 (4)
α, β, γ (°)	104.39 (2), 100.58 (2), 94.30 (2)
V (Å³)	546.8 (4)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.31
Crystal size (mm)	0.16 × 0.10 × 0.08

Data collection
Diffractometer	Nonius KappaCCD diffractometer
Absorption correction	Multi-scan (SORTAV; Blessing, 1997)
T_min, T_max	0.953, 0.976
No. of measured, independent and observed [I > 2σ(I)] reflections	4654, 2468, 2040
R_int	0.024
(sin θ/λ)_max (Å⁻¹)	0.647

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.040, 0.111, 1.03
No. of reflections	2468
No. of parameters	155
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.46, −0.43

Computer programs: COLLECT (Hooft, 1998), DENZO (Otwinowski & Minor, 1997), SCALEPACK (Otwinowski & Minor, 1997), SAPI91 (Fan, 1991), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O5ⁱ	0.95	2.53	3.435 (3)	160
C4—H4···O4ⁱⁱ	0.95	2.54	3.209 (3)	128
C8—H8A···O2ⁱⁱⁱ	0.99	2.49	3.435 (3)	159
C10—H10C···O1^iv	0.98	2.47	3.431 (3)	167

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

References

Blessing, R. H. (1997). J. Appl. Cryst. 30, 421–426. CrossRef CAS Web of Science IUCr Journals Google Scholar
Fan, H.-F. (1991). SAPI91. Rigaku Corporation, Tokyo, Japan. Google Scholar
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Volume 64| Part 5| May 2008| Page o859

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