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ISSN: 2056-9890

Propan-2-yl 2-(1,1,3-trioxo-2,3-di­hydro-1λ6,2-benzo­thia­zol-2-yl)acetate

aApplied Chemistry Research Centre, PCSIR Laboratories Complex, Lahore 54600, Pakistan, bInstitute of Chemistry, University of the Punjab, Lahore 54590, Pakistan, and cDepartment of Chemistry, The University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4
*Correspondence e-mail: rehman_pcsir@hotmail.com

(Received 12 August 2012; accepted 16 August 2012; online 23 August 2012)

In the title mol­ecule, C12H13NO5S, the benzisothia­zole ring system is essentially planar (r.m.s. deviation = 0.0169 Å) as is the –C—C(=O)—O—C– sequence of atoms in the vicinity of the acetate group (r.m.s. deviation = 0.0044 Å). The mean plane of these atoms forms a dihedral angle of 88.41 (7)° with the benzisothia­zole ring system. In the crystal, weak C—H⋯O hydrogen bonds involving methyl­ene and methyne H atoms form R43(20) graph-set motifs.

Related literature

For uses of 1,2-benzothia­zol-3(2H)-one 1,1-dioxide, see: Kap-Sun & Nicholas (1998[Kap-Sun, Y. & Nicholas, A. M. (1998). Tetrahedron Lett. 39, 5309-5312.]). For the synthesis of non-steroidal anti-inflammatory drugs (NSAIDs) and their biological evaluation, see: Ahmad et al. (2011[Ahmad, N., Zia-ur-Rehman, M., Siddiqui, H. L., Fasih Ullah, M. & Parvez, M. (2011). Eur. J. Med. Chem. 46, 2368-2377.]); Zia-ur-Rehman et al. (2009[Zia-ur-Rehman, M., Choudary, J. A., Elsegood, M. R. J., Siddiqui, H. L. & Khan, K. M. (2009). Eur. J. Med. Chem. 44, 1311-1316.]). For related structures, see: Sattar et al. (2012[Sattar, N., Siddiqui, H. L., Siddiqui, W. A., Akram, M. & Parvez, M. (2012). Acta Cryst. E68, o1889-o1890.]); Maliha et al. (2007[Maliha, B., Hussain, I., Siddiqui, H. L., Tariq, M. I. & Parvez, M. (2007). Acta Cryst. E63, o4728.]); Siddiqui et al. (2007[Siddiqui, W. A., Ahmad, S., Siddiqui, H. L., Tariq, M. I. & Parvez, M. (2007). Acta Cryst. E63, o4001.]). For graph-set motifs, see: (Bernstein et al., 1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N. L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C12H13NO5S

  • Mr = 283.29

  • Monoclinic, P 21 /n

  • a = 8.0922 (3) Å

  • b = 9.2314 (4) Å

  • c = 17.7414 (8) Å

  • β = 100.075 (2)°

  • V = 1304.89 (9) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.26 mm−1

  • T = 173 K

  • 0.14 × 0.12 × 0.06 mm

Data collection
  • Nonius KappaCCD diffractometer

  • Absorption correction: multi-scan (SORTAV; Blessing, 1997[Blessing, R. H. (1997). J. Appl. Cryst. 30, 421-426.]) Tmin = 0.964, Tmax = 0.984

  • 5518 measured reflections

  • 2953 independent reflections

  • 2339 reflections with I > 2σ(I)

  • Rint = 0.041

Refinement
  • R[F2 > 2σ(F2)] = 0.055

  • wR(F2) = 0.119

  • S = 1.11

  • 2953 reflections

  • 174 parameters

  • H-atom parameters constrained

  • Δρmax = 0.41 e Å−3

  • Δρmin = −0.43 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C8—H8B⋯O3i 0.99 2.27 3.236 (3) 166
C10—H10⋯O3ii 1.00 2.42 3.245 (3) 140
Symmetry codes: (i) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]; (ii) x+1, y, z.

Data collection: COLLECT (Hooft, 1998[Hooft, R. (1998). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

1,2-Benzothiazol-3(2H)-one 1,1-dioxide is known as an artificial sweetener commonly known as saccharin. It has been widely explored as a reactant of a number of medicinally important heterocyclic compounds (Kap-Sun & Nicholas, 1998), out of which oxicam family is the most important. N-alkylation of saccharin followed by base catalyzed ring expansion gives rise to methyl 4-hydroxy-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide (Zia-ur-Rehman et al., 2009) which is a basic precursor to the synthesis of Piroxicam, Meloxicam and Ampiroxicam. In continuation of our work on the synthesis and biological evaluation of thiazine based compounds (Ahmad et al., 2011), we herein report the crystal structure of the title compound.

In the title compound (Fig. 1), the benzisothiazol ring system S1/N1/C1–C7 is essentially planar with an r.m.s. deviation of the fitted atoms being 0.0169 Å. The O4/O5/C8-C10 sequence of atoms is also planar (r.m.s. deviation = 0.0044 Å) and forms a dihedral angle of 88.41 (7)° with the mean plane of the benzisothiazole ring system. The crystal packing is consolidated by weak intermolecular C—H···O hydrogen bonding interactions involving a H-atom of the methylene C8, C8—H8B···O3i, and a methyne H-atom bound to C10, C10—H10···O3ii, forming twenty membered rings in graph set motif R43(20) (Bernstein et al., 1995) (Fig. 2 & Tab. 1).

The bond distances and angles in the title compound agree very well with the corresponding bond distances and angles reported in closely related compounds (Sattar et al., 2012); Maliha et al., 2007; Siddiqui et al., 2007).

Related literature top

For uses of 1,2-benzothiazol-3(2H)-one 1,1-dioxide, see: Kap-Sun & Nicholas (1998). For the synthesis of non-steroidal anti-inflammatory drugs (NSAIDs) and their and biological evaluation, see: Ahmad et al. (2011); Zia-ur-Rehman et al. (2009). For related structures, see: Sattar et al. (2012); Maliha et al. (2007); Siddiqui et al. (2007). For graph-set motifs, see: (Bernstein et al., 1995).

Experimental top

A mixture of sodium saccharin (7.50 g; 36.55 mmol), N,N-dimethylformamide (50 ml) and isopropyl chloroacetate (4.99 g; 36.55 mmol) was taken in a round bottom flask and immersed in ultrasonic reaction bath at 333 K for a period of 15 min. The contents were then cooled to room temperature and poured over ice cooled water (300 ml) resulting in the formation of the title compound as a white solid, which was filtered and washed with cold water. The product was dried and recrystallized from isopropyl alcohol by slow evaporation to yield the crystal suitable for single crystal X-ray diffraction, yield = 94.4%; m.p. 392–394 K.

Refinement top

All H atoms were positioned geometrically and refined using a riding model, with C—H = 0.95, 0.98 and 0.99 Å, for aryl, methyl and methylene H-atoms, respectively. The Uiso(H) were allowed at 1.2Ueq(C).

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: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
Fig. 1. The molecular structure of the title compound with displacement ellipsoids drawn at the 50% probability level. H atoms are shown as small spheres of arbitrary radius.

Fig. 2. A part of the crystal structure showing the C—H···O hydrogen bonds (dotted lines) forming R43(20) graph set motifs. H atoms not involved in hydrogen bonds are omitted for clarity.
Propan-2-yl 2-(1,1,3-trioxo-2,3-dihydro-1λ6,2-benzothiazol-2-yl)acetate top
Crystal data top
C12H13NO5SF(000) = 592
Mr = 283.29Dx = 1.442 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2817 reflections
a = 8.0922 (3) Åθ = 1.0–27.5°
b = 9.2314 (4) ŵ = 0.26 mm1
c = 17.7414 (8) ÅT = 173 K
β = 100.075 (2)°Prism, colorless
V = 1304.89 (9) Å30.14 × 0.12 × 0.06 mm
Z = 4
Data collection top
Nonius KappaCCD
diffractometer
2953 independent reflections
Radiation source: fine-focus sealed tube2339 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.041
ω and ϕ scansθmax = 27.4°, θmin = 3.2°
Absorption correction: multi-scan
(SORTAV; Blessing, 1997)
h = 1010
Tmin = 0.964, Tmax = 0.984k = 1111
5518 measured reflectionsl = 2222
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.055Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.119H-atom parameters constrained
S = 1.11 w = 1/[σ2(Fo2) + (0.0186P)2 + 1.8823P]
where P = (Fo2 + 2Fc2)/3
2953 reflections(Δ/σ)max = 0.001
174 parametersΔρmax = 0.41 e Å3
0 restraintsΔρmin = 0.43 e Å3
Crystal data top
C12H13NO5SV = 1304.89 (9) Å3
Mr = 283.29Z = 4
Monoclinic, P21/nMo Kα radiation
a = 8.0922 (3) ŵ = 0.26 mm1
b = 9.2314 (4) ÅT = 173 K
c = 17.7414 (8) Å0.14 × 0.12 × 0.06 mm
β = 100.075 (2)°
Data collection top
Nonius KappaCCD
diffractometer
2953 independent reflections
Absorption correction: multi-scan
(SORTAV; Blessing, 1997)
2339 reflections with I > 2σ(I)
Tmin = 0.964, Tmax = 0.984Rint = 0.041
5518 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0550 restraints
wR(F2) = 0.119H-atom parameters constrained
S = 1.11Δρmax = 0.41 e Å3
2953 reflectionsΔρmin = 0.43 e Å3
174 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
xyzUiso*/Ueq
S10.71458 (8)0.28520 (7)0.59318 (4)0.02941 (18)
O10.6975 (3)0.4281 (2)0.62206 (12)0.0414 (5)
O20.8538 (2)0.2573 (2)0.55647 (11)0.0423 (5)
O30.5438 (2)0.0124 (2)0.70065 (10)0.0335 (4)
O40.9985 (3)0.0077 (2)0.68519 (12)0.0488 (6)
O51.0959 (2)0.1079 (2)0.79588 (10)0.0311 (4)
N10.7092 (3)0.1656 (2)0.66356 (12)0.0277 (5)
C10.5243 (3)0.2216 (3)0.54085 (13)0.0250 (5)
C20.4415 (3)0.2730 (3)0.47085 (14)0.0321 (6)
H20.48730.34750.44380.039*
C30.2872 (3)0.2088 (3)0.44250 (15)0.0362 (7)
H30.22590.24070.39480.043*
C40.2206 (3)0.1002 (3)0.48162 (15)0.0350 (6)
H40.11490.05940.46050.042*
C50.3061 (3)0.0497 (3)0.55150 (15)0.0293 (6)
H50.26050.02480.57860.035*
C60.4602 (3)0.1119 (3)0.58023 (13)0.0234 (5)
C70.5697 (3)0.0762 (3)0.65414 (14)0.0257 (5)
C80.8296 (3)0.1713 (3)0.73484 (14)0.0314 (6)
H8A0.77370.13900.77730.038*
H8B0.86560.27300.74510.038*
C90.9831 (3)0.0785 (3)0.73385 (14)0.0301 (6)
C101.2566 (3)0.0297 (3)0.80553 (16)0.0350 (6)
H101.29160.01730.75460.042*
C111.3818 (4)0.1243 (4)0.8560 (2)0.0526 (9)
H11A1.49290.07900.86290.063*
H11B1.34750.13590.90600.063*
H11C1.38640.21950.83200.063*
C121.2351 (4)0.1147 (4)0.8396 (2)0.0501 (8)
H12A1.34040.16910.84440.060*
H12B1.14580.16800.80650.060*
H12C1.20480.10220.89030.060*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0286 (3)0.0264 (3)0.0310 (3)0.0029 (3)0.0007 (2)0.0048 (3)
O10.0497 (12)0.0242 (10)0.0452 (12)0.0044 (9)0.0059 (9)0.0021 (9)
O20.0295 (10)0.0523 (13)0.0462 (12)0.0056 (10)0.0100 (9)0.0067 (10)
O30.0376 (10)0.0338 (10)0.0291 (9)0.0005 (9)0.0057 (8)0.0080 (8)
O40.0480 (13)0.0531 (14)0.0386 (11)0.0179 (11)0.0107 (9)0.0165 (10)
O50.0254 (9)0.0375 (11)0.0275 (9)0.0022 (8)0.0034 (7)0.0044 (8)
N10.0281 (11)0.0263 (11)0.0257 (11)0.0001 (9)0.0035 (9)0.0036 (9)
C10.0239 (12)0.0249 (12)0.0253 (12)0.0039 (10)0.0019 (9)0.0003 (10)
C20.0324 (14)0.0362 (15)0.0280 (13)0.0062 (12)0.0057 (11)0.0066 (12)
C30.0323 (14)0.0452 (17)0.0281 (13)0.0119 (13)0.0035 (11)0.0039 (13)
C40.0257 (13)0.0436 (16)0.0329 (14)0.0012 (12)0.0027 (11)0.0058 (13)
C50.0258 (13)0.0315 (14)0.0309 (13)0.0000 (11)0.0063 (10)0.0037 (11)
C60.0241 (12)0.0225 (12)0.0235 (12)0.0030 (10)0.0039 (9)0.0009 (10)
C70.0258 (12)0.0255 (13)0.0254 (12)0.0030 (10)0.0036 (10)0.0005 (10)
C80.0332 (14)0.0313 (14)0.0259 (12)0.0005 (11)0.0057 (11)0.0020 (11)
C90.0323 (14)0.0310 (14)0.0239 (12)0.0017 (11)0.0033 (10)0.0005 (11)
C100.0240 (13)0.0438 (16)0.0369 (14)0.0018 (12)0.0047 (11)0.0011 (13)
C110.0359 (17)0.055 (2)0.061 (2)0.0069 (15)0.0066 (15)0.0023 (17)
C120.0375 (17)0.0480 (19)0.062 (2)0.0002 (15)0.0017 (15)0.0066 (17)
Geometric parameters (Å, º) top
S1—O21.420 (2)C4—H40.9500
S1—O11.431 (2)C5—C61.387 (3)
S1—N11.673 (2)C5—H50.9500
S1—C11.754 (2)C6—C71.485 (3)
O3—C71.206 (3)C8—C91.511 (4)
O4—C91.197 (3)C8—H8A0.9900
O5—C91.329 (3)C8—H8B0.9900
O5—C101.471 (3)C10—C121.486 (4)
N1—C71.385 (3)C10—C111.508 (4)
N1—C81.456 (3)C10—H101.0000
C1—C61.381 (3)C11—H11A0.9800
C1—C21.388 (3)C11—H11B0.9800
C2—C31.395 (4)C11—H11C0.9800
C2—H20.9500C12—H12A0.9800
C3—C41.381 (4)C12—H12B0.9800
C3—H30.9500C12—H12C0.9800
C4—C51.390 (4)
O2—S1—O1117.72 (13)O3—C7—C6127.4 (2)
O2—S1—N1110.45 (12)N1—C7—C6108.8 (2)
O1—S1—N1108.93 (12)N1—C8—C9113.3 (2)
O2—S1—C1112.96 (12)N1—C8—H8A108.9
O1—S1—C1111.56 (12)C9—C8—H8A108.9
N1—S1—C192.23 (11)N1—C8—H8B108.9
C9—O5—C10117.5 (2)C9—C8—H8B108.9
C7—N1—C8122.3 (2)H8A—C8—H8B107.7
C7—N1—S1115.50 (16)O4—C9—O5126.2 (2)
C8—N1—S1121.56 (18)O4—C9—C8125.1 (2)
C6—C1—C2122.6 (2)O5—C9—C8108.7 (2)
C6—C1—S1110.48 (17)O5—C10—C12108.9 (2)
C2—C1—S1126.9 (2)O5—C10—C11105.9 (2)
C1—C2—C3116.0 (3)C12—C10—C11113.1 (3)
C1—C2—H2122.0O5—C10—H10109.6
C3—C2—H2122.0C12—C10—H10109.6
C4—C3—C2122.1 (2)C11—C10—H10109.6
C4—C3—H3119.0C10—C11—H11A109.5
C2—C3—H3119.0C10—C11—H11B109.5
C3—C4—C5121.0 (2)H11A—C11—H11B109.5
C3—C4—H4119.5C10—C11—H11C109.5
C5—C4—H4119.5H11A—C11—H11C109.5
C6—C5—C4117.7 (3)H11B—C11—H11C109.5
C6—C5—H5121.2C10—C12—H12A109.5
C4—C5—H5121.2C10—C12—H12B109.5
C1—C6—C5120.7 (2)H12A—C12—H12B109.5
C1—C6—C7113.0 (2)C10—C12—H12C109.5
C5—C6—C7126.3 (2)H12A—C12—H12C109.5
O3—C7—N1123.9 (2)H12B—C12—H12C109.5
O2—S1—N1—C7116.8 (2)S1—C1—C6—C71.2 (3)
O1—S1—N1—C7112.4 (2)C4—C5—C6—C10.9 (4)
C1—S1—N1—C71.3 (2)C4—C5—C6—C7178.7 (2)
O2—S1—N1—C872.3 (2)C8—N1—C7—O36.7 (4)
O1—S1—N1—C858.4 (2)S1—N1—C7—O3177.5 (2)
C1—S1—N1—C8172.1 (2)C8—N1—C7—C6171.6 (2)
O2—S1—C1—C6114.72 (19)S1—N1—C7—C60.8 (3)
O1—S1—C1—C6110.00 (19)C1—C6—C7—O3178.5 (3)
N1—S1—C1—C61.38 (19)C5—C6—C7—O30.6 (4)
O2—S1—C1—C267.2 (3)C1—C6—C7—N10.3 (3)
O1—S1—C1—C268.1 (3)C5—C6—C7—N1177.6 (2)
N1—S1—C1—C2179.5 (2)C7—N1—C8—C997.6 (3)
C6—C1—C2—C30.9 (4)S1—N1—C8—C992.1 (3)
S1—C1—C2—C3177.0 (2)C10—O5—C9—O41.2 (4)
C1—C2—C3—C40.1 (4)C10—O5—C9—C8179.3 (2)
C2—C3—C4—C50.2 (4)N1—C8—C9—O410.1 (4)
C3—C4—C5—C60.2 (4)N1—C8—C9—O5170.5 (2)
C2—C1—C6—C51.3 (4)C9—O5—C10—C1282.6 (3)
S1—C1—C6—C5176.86 (19)C9—O5—C10—C11155.5 (2)
C2—C1—C6—C7179.3 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8B···O3i0.992.273.236 (3)166
C10—H10···O3ii1.002.423.245 (3)140
Symmetry codes: (i) x+3/2, y+1/2, z+3/2; (ii) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC12H13NO5S
Mr283.29
Crystal system, space groupMonoclinic, P21/n
Temperature (K)173
a, b, c (Å)8.0922 (3), 9.2314 (4), 17.7414 (8)
β (°) 100.075 (2)
V3)1304.89 (9)
Z4
Radiation typeMo Kα
µ (mm1)0.26
Crystal size (mm)0.14 × 0.12 × 0.06
Data collection
DiffractometerNonius KappaCCD
diffractometer
Absorption correctionMulti-scan
(SORTAV; Blessing, 1997)
Tmin, Tmax0.964, 0.984
No. of measured, independent and
observed [I > 2σ(I)] reflections
5518, 2953, 2339
Rint0.041
(sin θ/λ)max1)0.648
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.055, 0.119, 1.11
No. of reflections2953
No. of parameters174
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.41, 0.43

Computer programs: COLLECT (Hooft, 1998), DENZO (Otwinowski & Minor, 1997), SCALEPACK (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8B···O3i0.992.273.236 (3)165.7
C10—H10···O3ii1.002.423.245 (3)139.8
Symmetry codes: (i) x+3/2, y+1/2, z+3/2; (ii) x+1, y, z.
 

Acknowledgements

The authors are grateful to the Higher Education Commission of Pakistan and PCSIR for the support to carry out this work.

References

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