organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

Methyl 4-acet­­oxy-2-methyl-2H-1,2-benzo­thia­zine-3-carboxyl­ate 1,1-dioxide

aInstitute of Chemistry, University of the Punjab, Lahore 54600, Pakistan, bDepartment of Chemistry, University of Science and Technology, Bannu, Pakistan, and cSchool of Chemistry, University of Southampton, England
*Correspondence e-mail: drhamidlatif@yahoo.com

(Received 12 December 2007; accepted 7 February 2008; online 15 February 2008)

In the title compound, C13H13NO6S, the thia­zine ring adopts a distorted half-chair conformation. Each mol­ecule is linked to its neighbour through inter­molecular C—H⋯O hydrogen bonds.

Related literature

For related literature, see: Fabiola et al. (1998[Fabiola, G. F., Pattabhi, V., Manjunatha, S. G., Rao, G. V. & Nagarajan, K. (1998). Acta Cryst. C54, 2001-2003.]); Golič & Leban (1987[Golič, L. & Leban, I. (1987). Acta Cryst. C43, 280-282.]); Kojić-Prodić & Rużić-Toroš (1982[Kojić-Prodić, B. & Rużić-Toroš, Ž. (1982). Acta Cryst. B38, 2948-2951.]); Rajagopal & Seshadri (1990[Rajagopal, R. & Seshadri, S. (1990). Dyes Pigments, 13, 93-99.]); Reck et al. (1988[Reck, G., Dietz, G., Laban, G., Gunter, W., Bannier, G. & Hohne, E. (1988). Pharmazie, 43, 477-481.]); Rehman et al. (2005[Rehman, M. Z., Choudary, J. A. & Ahmad, S. (2005). Bull. Korean Chem. Soc. 26, 1171-1175.], 2006[Rehman, M. Z., Choudary, J. A., Ahmad, S. & Siddiqui, H. L. (2006). Chem. Pharm. Bull. 54, 1175-1178.]); Turck et al. (1996[Turck, D., Busch, U., Heinzel, G., Narjes, H. & Nehmiz, G. (1996). Clin. Pharm. 36, 79-84.]).

[Scheme 1]

Experimental

Crystal data
  • C13H13NO6S

  • Mr = 311.30

  • Monoclinic, P 21 /c

  • a = 6.8917 (5) Å

  • b = 24.1814 (17) Å

  • c = 8.2861 (5) Å

  • β = 97.876 (4)°

  • V = 1367.86 (16) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.26 mm−1

  • T = 120 (2) K

  • 0.40 × 0.20 × 0.20 mm

Data collection
  • Bruker Nonius KappaCCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2007[Sheldrick, G. M. (2007). SADABS. Version 2007/2. University of Göttingen, Germany.]) Tmin = 0.902, Tmax = 0.949

  • 12265 measured reflections

  • 3032 independent reflections

  • 2183 reflections with I > 2σ(I)

  • Rint = 0.057

Refinement
  • R[F2 > 2σ(F2)] = 0.050

  • wR(F2) = 0.145

  • S = 1.03

  • 3032 reflections

  • 193 parameters

  • H-atom parameters constrained

  • Δρmax = 0.36 e Å−3

  • Δρmin = −0.55 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C13—H13A⋯O4i 0.98 2.48 3.387 (3) 153
C5—H5⋯O1i 0.95 2.48 3.349 (3) 151
Symmetry code: (i) x, y, z-1.

Data collection: COLLECT (Nonius, 1998[Nonius (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.]) and COLLECT; data reduction: DENZO and COLLECT; 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: CAMERON (Pearce & Watkin, 1993[Pearce, L. J. & Watkin, D. J. (1993). CAMERON. Chemical Crystallography Laboratory, University of Oxford, England.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

Among the vast class of benzothiazines, 1,2-benzothiazine1,1-dioxides are the most versatile compounds due to their applications in various fields such as pharmaceuticals (Turck et al., 1996), dyes (Rajagopal & Seshadri, 1990) and fungicides. In continuation of our investigation of the chemistry of 1,2-benzothiazine 1,1-dioxide derivatives (Rehman et al., 2005; Rehman et al., 2006) we have synthesized the title compound (I) and its crystal structure is reported here.

In (I) (Fig. 1), the benzene ring of the benzothiazine nucleus is planar (the maximum least square deviation from the plane of the atoms involved is 0.01 Å) while the thiazine ring adopts a distorted half chair conformation. N1 has a pyramidal geometry projecting the methyl group approximately perpendicular to the thiazine ring. Atoms O1, O3 and O5 lie approximately in the plane of the ring while O2 lies almost perpendicular to it.

The C7—O3 bond length in (I) is longer [1.389 (3)] than in the related molecules having no substitution at O3 [1.352 (9) Å; Golič & Leban, 1987; 1.350 (9) Å; Reck et al., 1988].

C9—O4 bond length [1.201 (13) Å] is observed to be shorter than in its previously reported non acylated analogue [1.262 (10) Å; Golič & Leban, 1987] due to no involvement of O4 electrons in the hydrogen bonding. O4 lies almost perpendicular to the thiazine ring and the bond angle C7—C8—C9 [127.3 (2) Å] is greater than observed in the related hydrogen bonded oxicams [121.0 (3) Å; Kojić-Prodić & Rużić-Toroš, 1982; 120.9 (2) Å, Fabiola et al., 1998]. Molecules are linked by C—H···O hydrogen bonds (Table1) forming a chain along a axis.

Related literature top

For related literature, see: Fabiola et al. (1998); Golič & Leban (1987); Kojić-Prodić & Rużić-Toroš (1982); Rajagopal & Seshadri (1990); Reck et al. (1988); Rehman et al. (2005, 2006); Turck et al. (1996).

Experimental top

Acetyl chloride (1.57 g; 10 mmol) was slowly added to a mixture of methyl 4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxylate1,1-dioxide (1.345 g; 5 mmol), triethylamine (0.71 g; 7 mmol) and carbon tetrachloride (25 ml) under nitrogen atmosphere at 273 K. The mixture was stirred for a period of three hours at room temperature and the solvent was evaporated under vacuum. A residue was poured over ice-water mixture to get the white coloured product which was washed with cold water and recrystallized from chloroform-methanol mixture (1:1). Yield 1.31 g; 84°; m.p. 422 K.

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997) and COLLECT (Nonius, 1998); data reduction: DENZO (Otwinowski & Minor, 1997) and COLLECT (Nonius, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CAMERON (Pearce & Watkin, 1993); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), showing displacement ellipsoids at the 50% probability level for non-H atoms. Dashed lines denote hydrogen bonds.
Methyl 4-acetoxy-2-methyl-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide top
Crystal data top
C13H13NO6SF(000) = 648
Mr = 311.30Dx = 1.512 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 15145 reflections
a = 6.8917 (5) Åθ = 2.9–27.5°
b = 24.1814 (17) ŵ = 0.26 mm1
c = 8.2861 (5) ÅT = 120 K
β = 97.876 (4)°Block, colourless
V = 1367.86 (16) Å30.40 × 0.20 × 0.20 mm
Z = 4
Data collection top
Bruker Nonius CCD camera on κ-goniostat
diffractometer
3032 independent reflections
Radiation source: Bruker Nonius FR591 Rotating Anode2183 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.057
Detector resolution: 9.091 pixels mm-1θmax = 27.5°, θmin = 3.0°
ϕ and ω scans to fill the asymmetric unith = 88
Absorption correction: multi-scan
(SADABS; Sheldrick, 2007)
k = 3130
Tmin = 0.902, Tmax = 0.949l = 109
12265 measured reflections
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)] = 0.050Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.145H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0764P)2 + 0.6225P]
where P = (Fo2 + 2Fc2)/3
3032 reflections(Δ/σ)max = 0.001
193 parametersΔρmax = 0.36 e Å3
0 restraintsΔρmin = 0.55 e Å3
Crystal data top
C13H13NO6SV = 1367.86 (16) Å3
Mr = 311.30Z = 4
Monoclinic, P21/cMo Kα radiation
a = 6.8917 (5) ŵ = 0.26 mm1
b = 24.1814 (17) ÅT = 120 K
c = 8.2861 (5) Å0.40 × 0.20 × 0.20 mm
β = 97.876 (4)°
Data collection top
Bruker Nonius CCD camera on κ-goniostat
diffractometer
3032 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2007)
2183 reflections with I > 2σ(I)
Tmin = 0.902, Tmax = 0.949Rint = 0.057
12265 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0500 restraints
wR(F2) = 0.145H-atom parameters constrained
S = 1.03Δρmax = 0.36 e Å3
3032 reflectionsΔρmin = 0.55 e Å3
193 parameters
Special details top

Experimental. SADABS was used to perform the Absorption correction Estimated minimum and maximum transmission: 0.6195 0.7456 The given Tmin and Tmax were generated using the SHELX SIZE command

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
C10.5172 (4)0.43090 (10)0.7387 (3)0.0183 (5)
C20.7043 (4)0.45347 (10)0.7686 (3)0.0213 (6)
H20.76290.46160.87660.026*
C30.8032 (4)0.46376 (10)0.6369 (3)0.0213 (5)
H30.93150.47900.65440.026*
C40.7153 (4)0.45192 (10)0.4788 (3)0.0219 (6)
H40.78360.45970.38930.026*
C50.5299 (4)0.42895 (9)0.4508 (3)0.0183 (5)
H50.47190.42110.34250.022*
C60.4276 (4)0.41729 (9)0.5809 (3)0.0167 (5)
C70.2364 (3)0.39001 (9)0.5570 (3)0.0162 (5)
C80.1613 (4)0.36162 (10)0.6749 (3)0.0181 (5)
C90.0253 (4)0.32911 (10)0.6577 (3)0.0202 (6)
C100.2808 (4)0.28845 (11)0.4788 (3)0.0301 (6)
H10A0.25440.25100.52150.045*
H10B0.32980.28650.36220.045*
H10C0.37930.30610.53640.045*
C110.3594 (4)0.30948 (11)0.8954 (3)0.0294 (7)
H11A0.27110.27840.86430.044*
H11B0.39140.31071.01430.044*
H11C0.48000.30480.84640.044*
C120.1291 (4)0.35858 (10)0.2862 (3)0.0207 (6)
C130.0222 (4)0.37189 (12)0.1456 (3)0.0307 (7)
H13A0.01280.34550.05720.046*
H13B0.00080.40940.10730.046*
H13C0.15260.36950.17960.046*
N10.2622 (3)0.36187 (8)0.8366 (2)0.0185 (5)
O10.4912 (3)0.41115 (8)1.04687 (19)0.0263 (4)
O20.2249 (3)0.46261 (7)0.8823 (2)0.0234 (4)
O30.1272 (2)0.39845 (6)0.40526 (18)0.0184 (4)
O40.0967 (3)0.31203 (8)0.7727 (2)0.0353 (5)
O50.1014 (3)0.32064 (7)0.5028 (2)0.0266 (4)
O60.2420 (3)0.32061 (7)0.3014 (2)0.0282 (5)
S10.37225 (9)0.42031 (2)0.89441 (7)0.0197 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0191 (13)0.0190 (12)0.0169 (12)0.0010 (10)0.0030 (10)0.0017 (9)
C20.0201 (14)0.0197 (12)0.0222 (13)0.0006 (10)0.0035 (10)0.0003 (10)
C30.0138 (13)0.0196 (12)0.0302 (14)0.0010 (10)0.0021 (10)0.0026 (11)
C40.0205 (14)0.0207 (12)0.0260 (13)0.0023 (10)0.0082 (10)0.0032 (10)
C50.0193 (14)0.0183 (12)0.0175 (12)0.0029 (10)0.0034 (10)0.0009 (9)
C60.0162 (13)0.0149 (11)0.0182 (12)0.0021 (9)0.0003 (10)0.0017 (9)
C70.0146 (12)0.0198 (12)0.0135 (11)0.0019 (10)0.0006 (9)0.0019 (9)
C80.0204 (14)0.0183 (12)0.0151 (11)0.0004 (10)0.0009 (9)0.0017 (9)
C90.0214 (14)0.0197 (12)0.0201 (13)0.0000 (10)0.0047 (10)0.0040 (10)
C100.0250 (16)0.0325 (15)0.0320 (15)0.0132 (12)0.0013 (12)0.0068 (12)
C110.0372 (17)0.0243 (14)0.0257 (14)0.0046 (12)0.0006 (12)0.0038 (11)
C120.0186 (14)0.0267 (13)0.0175 (12)0.0040 (11)0.0046 (10)0.0015 (10)
C130.0280 (16)0.0437 (17)0.0190 (13)0.0027 (13)0.0015 (11)0.0039 (12)
N10.0192 (12)0.0202 (10)0.0157 (10)0.0012 (8)0.0013 (8)0.0007 (8)
O10.0243 (11)0.0390 (11)0.0141 (9)0.0034 (8)0.0023 (7)0.0010 (8)
O20.0248 (10)0.0230 (9)0.0223 (9)0.0011 (7)0.0031 (7)0.0041 (7)
O30.0176 (9)0.0218 (9)0.0152 (8)0.0003 (7)0.0003 (7)0.0008 (7)
O40.0386 (13)0.0458 (12)0.0225 (10)0.0196 (10)0.0080 (9)0.0008 (9)
O50.0222 (10)0.0351 (10)0.0223 (9)0.0119 (8)0.0020 (7)0.0044 (8)
O60.0308 (11)0.0284 (10)0.0259 (10)0.0028 (8)0.0054 (8)0.0049 (8)
S10.0207 (4)0.0234 (3)0.0147 (3)0.0017 (2)0.0014 (2)0.0012 (2)
Geometric parameters (Å, º) top
C1—C21.391 (3)C10—O51.451 (3)
C1—C61.407 (3)C10—H10A0.9800
C1—S11.755 (3)C10—H10B0.9800
C2—C31.386 (4)C10—H10C0.9800
C2—H20.9500C11—N11.484 (3)
C3—C41.396 (3)C11—H11A0.9800
C3—H30.9500C11—H11B0.9800
C4—C51.384 (3)C11—H11C0.9800
C4—H40.9500C12—O61.199 (3)
C5—C61.396 (3)C12—O31.380 (3)
C5—H50.9500C12—C131.488 (3)
C6—C71.463 (3)C13—H13A0.9800
C7—C81.353 (3)C13—H13B0.9800
C7—O31.389 (3)C13—H13C0.9800
C8—N11.422 (3)N1—S11.644 (2)
C8—C91.498 (3)O1—S11.4258 (17)
C9—O41.203 (3)O2—S11.4354 (18)
C9—O51.334 (3)
C2—C1—C6122.4 (2)O5—C10—H10C109.5
C2—C1—S1122.25 (18)H10A—C10—H10C109.5
C6—C1—S1115.33 (18)H10B—C10—H10C109.5
C3—C2—C1118.3 (2)N1—C11—H11A109.5
C3—C2—H2120.8N1—C11—H11B109.5
C1—C2—H2120.8H11A—C11—H11B109.5
C2—C3—C4120.4 (2)N1—C11—H11C109.5
C2—C3—H3119.8H11A—C11—H11C109.5
C4—C3—H3119.8H11B—C11—H11C109.5
C5—C4—C3120.8 (2)O6—C12—O3121.9 (2)
C5—C4—H4119.6O6—C12—C13128.5 (2)
C3—C4—H4119.6O3—C12—C13109.5 (2)
C4—C5—C6120.3 (2)C12—C13—H13A109.5
C4—C5—H5119.9C12—C13—H13B109.5
C6—C5—H5119.9H13A—C13—H13B109.5
C5—C6—C1117.9 (2)C12—C13—H13C109.5
C5—C6—C7121.9 (2)H13A—C13—H13C109.5
C1—C6—C7120.2 (2)H13B—C13—H13C109.5
C8—C7—O3121.0 (2)C8—N1—C11116.50 (18)
C8—C7—C6123.9 (2)C8—N1—S1115.14 (15)
O3—C7—C6114.97 (19)C11—N1—S1117.95 (17)
C7—C8—N1119.5 (2)C12—O3—C7119.17 (18)
C7—C8—C9127.3 (2)C9—O5—C10115.4 (2)
N1—C8—C9113.2 (2)O1—S1—O2119.20 (10)
O4—C9—O5124.0 (2)O1—S1—N1108.13 (11)
O4—C9—C8123.0 (2)O2—S1—N1107.37 (10)
O5—C9—C8113.0 (2)O1—S1—C1110.97 (12)
O5—C10—H10A109.5O2—S1—C1108.25 (11)
O5—C10—H10B109.5N1—S1—C1101.39 (11)
H10A—C10—H10B109.5
C6—C1—C2—C31.3 (4)C7—C8—N1—C11108.8 (3)
S1—C1—C2—C3175.79 (18)C9—C8—N1—C1172.3 (3)
C1—C2—C3—C40.4 (4)C7—C8—N1—S135.6 (3)
C2—C3—C4—C51.1 (4)C9—C8—N1—S1143.34 (17)
C3—C4—C5—C60.1 (4)O6—C12—O3—C710.5 (3)
C4—C5—C6—C11.6 (3)C13—C12—O3—C7170.6 (2)
C4—C5—C6—C7176.3 (2)C8—C7—O3—C1286.4 (3)
C2—C1—C6—C52.3 (3)C6—C7—O3—C1298.0 (2)
S1—C1—C6—C5175.01 (17)O4—C9—O5—C100.2 (4)
C2—C1—C6—C7175.6 (2)C8—C9—O5—C10178.9 (2)
S1—C1—C6—C77.1 (3)C8—N1—S1—O1170.76 (17)
C5—C6—C7—C8157.1 (2)C11—N1—S1—O127.0 (2)
C1—C6—C7—C820.7 (4)C8—N1—S1—O259.42 (19)
C5—C6—C7—O327.4 (3)C11—N1—S1—O2156.78 (18)
C1—C6—C7—O3154.8 (2)C8—N1—S1—C154.01 (19)
O3—C7—C8—N1169.13 (19)C11—N1—S1—C189.79 (19)
C6—C7—C8—N16.2 (4)C2—C1—S1—O128.5 (2)
O3—C7—C8—C99.6 (4)C6—C1—S1—O1154.23 (17)
C6—C7—C8—C9175.1 (2)C2—C1—S1—O2104.1 (2)
C7—C8—C9—O4168.4 (3)C6—C1—S1—O273.2 (2)
N1—C8—C9—O410.4 (3)C2—C1—S1—N1143.1 (2)
C7—C8—C9—O512.4 (4)C6—C1—S1—N139.6 (2)
N1—C8—C9—O5168.8 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13A···O4i0.982.493.387 (3)153
C5—H5···O1i0.952.483.349 (3)151
Symmetry code: (i) x, y, z1.

Experimental details

Crystal data
Chemical formulaC13H13NO6S
Mr311.30
Crystal system, space groupMonoclinic, P21/c
Temperature (K)120
a, b, c (Å)6.8917 (5), 24.1814 (17), 8.2861 (5)
β (°) 97.876 (4)
V3)1367.86 (16)
Z4
Radiation typeMo Kα
µ (mm1)0.26
Crystal size (mm)0.40 × 0.20 × 0.20
Data collection
DiffractometerBruker Nonius CCD camera on κ-goniostat
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2007)
Tmin, Tmax0.902, 0.949
No. of measured, independent and
observed [I > 2σ(I)] reflections
12265, 3032, 2183
Rint0.057
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.050, 0.145, 1.03
No. of reflections3032
No. of parameters193
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.36, 0.55

Computer programs: , DENZO (Otwinowski & Minor, 1997) and COLLECT (Nonius, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), CAMERON (Pearce & Watkin, 1993), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13A···O4i0.982.4853.387 (3)153
C5—H5···O1i0.952.4833.349 (3)151
Symmetry code: (i) x, y, z1.
 

Acknowledgements

The authors acknowledge financial support from the Higher Education Commission of Pakistan and the University of the Punjab, Lahore.

References

First citationFabiola, G. F., Pattabhi, V., Manjunatha, S. G., Rao, G. V. & Nagarajan, K. (1998). Acta Cryst. C54, 2001–2003.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
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