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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 64| Part 3| March 2008| Page o558
doi:10.1107/S1600536808003504

1-Ethyl-1H-2,1-benzo­thia­zin-4(3H)-one 2,2-dioxide

Muhammad Shafiq,a Islam Ullah Khan,a M. Nawaz Tahirb* and Waseeq Ahmad Siddiquic

aGovernment College University, Department of Chemistry, Lahore, Pakistan, bDepartment of Physics, University of Sargodha, Sargodha, Pakistan, and cDepartment of Chemistry, University of Sargodha, Sargodha, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 14 January 2008; accepted 31 January 2008; online 6 February 2008)

In the title compound, C10H11NO3S, there is distorted tetra­hedral geometry around the S atom. The heterocyclic thia­zine ring adopts a half-chair conformation. The ethyl and sulfonyl groups form dihedral angles of 82.53 (13) and 88.91 (9)°, respectively, with the plane formed by the benzothia­zine ring, excluding the S atom; the S atom and the ethyl group lie on opposite sides of the ring. The mol­ecules are linked into dimers by inter­molecular C—H⋯O hydrogen bonds involving benzene C—H and carbonyl O atoms, thus forming eight-membered rings. The dimers are linked into chains via inter­actions of a similar type. There is an intra­molecular C—H⋯O hydrogen bond.

Related literature

For related literature, see: Hanson et al. (1999[Hanson, P. R., Probst, D. A., Robinson, R. E. & Yau, M. (1999). Tetrahedron Lett. 40, 4761-4764.]); Misu & Togo (2003[Misu, Y. & Togo, H. (2003). Org. Biomol. Chem. 1, 1342-1346.]); Shafiq et al. (2008[Shafiq, M., Tahir, M. N., Khan, I. U., Siddiqui, W. A. & Arshad, M. N. (2008). Acta Cryst. E64, o389.]); Siddique et al. (2006[Siddique, W. A., Ahmad, S., Khan, I. U. & Malik, A. (2006). J. Chem. Soc. Pak. 28, 583-589.]); Siddiqui et al. (2007[Siddiqui, W. A., Ahmad, S., Khan, I. U., Siddiqui, H. L. & Weaver, G. W. (2007). Synth. Commun. 37, 767-773.]); Tahir et al. (2008[Tahir, M. N., Shafiq, M., Khan, I. U., Siddiqui, W. A. & Arshad, M. N. (2008). Acta Cryst. E64, o557.]); Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data

  • C10H11NO3S

  • Mr = 225.26

  • Triclinic, [P \overline 1]

  • a = 7.0272 (3) Å

  • b = 8.0448 (4) Å

  • c = 9.5880 (4) Å

  • α = 99.124 (3)°

  • β = 95.075 (3)°

  • γ = 104.092 (3)°

  • V = 514.48 (4) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.30 mm−1

  • T = 296 (2) K

  • 0.15 × 0.12 × 0.10 mm
Data collection

  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.965, Tmax = 0.988

  • 11339 measured reflections

  • 2608 independent reflections

  • 1760 reflections with I > 2σ(I)

  • Rint = 0.036
Refinement

  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.107

  • S = 1.02

  • 2608 reflections

  • 136 parameters

  • H-atom parameters constrained

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.26 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C2—H2⋯O3i 0.93 2.56 3.478 (3) 169
C8—H8A⋯O1ii 0.97 2.50 3.388 (3) 152
C9—H9B⋯O2 0.97 2.36 2.855 (3) 111
Symmetry codes: (i) x, y+1, z; (ii) -x+1, -y, -z+2.

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 (Version 1.27) and SAINT (Version 7.12a). Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2007[Bruker (2007). APEX2 (Version 1.27) and SAINT (Version 7.12a). Bruker AXS Inc., Madison, Wisconsin, USA.]); 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.]) and PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808003504/pv2067sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808003504/pv2067Isup2.hkl

checkCIF report


Comment top

Sulfonamides in general, and cyclic sulfonamides (sultams) in particular are important therapeutic compounds (Hanson et al., 1999). Among sultams, 1,2-benzothiazine and 2,1-benzothiazine dioxides (benzosultams) have proven to be biologically active (Misu & Togo, 2003). Due to the importance of 2,1-benzothiazine derivatives in medicinal chemistry, their synthesis has gained enormous attention. After accomplishing the synthesis of a number of 1,2-benzothiazine 1,1-dioxide derivatives (Siddique et al., 2006 and Siddiqui et al., 2007), we have recently started the synthesis of various 2,1-benzothiazine 2,2-dioxide derivatives.

The title compound, (I), was synthesized in continuation to our research on derivatives of 2,1-benzothiazine. It is a cyclized product of methyl 2-(N-ethylmethanesulfonamido)benzoate (Shafiq et al., 2008). The hetrocyclic ring adopts a half chair confirmation which may be described by the puckering parameters (Cremer & Pople, 19975): Q = 0.554 (2) Å, θ = 53.6 (2)° and ϕ = 356.2 (3)°. The structure of (I) can be best compared with its 1-methyl analogue (Tahir et al., 2008). In (I), the bond distance N1—C9 [1.477 (2) Å] is significantly longer than the corresponding distance [1.452 (2) Å] in the 1-methyl analogue. The range of bond angles around S in the two structures are essentially identical. All the atoms in the benzothiazine ring in (I) are nearly planer except that of S1 which is displaced by 0.783 (2) Å from the plane defined by C1—C8/N1, while C9-atom of N-ethyl group is at a distance of -0.226 (3) Å. The N-ethyl and sulfonyl groups form dihedral angles of 82.53 (13)° and 88.91 (9)°, respectively, with the plane formed by C1—C8/N1 atoms. The dihedral angle between these two groups is 46.66 (5)°. In the asymmetric unit there is an intramolecular H-bond between C9 and O2 atoms. The molecules are dimerized by forming eight member rings through H-bonding between methylene group of thiazine ring and sulfonyl O-atom (C8—H8···O1). The structure is further stabilized by interactions involving phenyl C—H and carbonyl O-atoms (C2—H2···O3) linking dimers into chains. Fig. 2 shows hydrogen bonding interactions; details of H-bonding geometry are given in Table 1.

Related literature top

For related literature, see: Hanson et al. (1999); Misu & Togo (2003); Shafiq et al. (2008); Siddique et al. (2006); Siddiqui et al. (2007); Tahir et al. (2008); Cremer & Pople (1975).

Experimental top

A suspension of hexane-washed sodium hydride (4.6 g, 96.0 mmol., 50% in mineral oil) was prepared in dry dimethylformamide (30 ml). To this suspension, a solution of methyl 2-(N-ethylmethanesulfonamido)benzoate (19.02 g, 74.0 mmol) in dry dimethylformamide (70 ml) was added. The reaction mixture was stirred at room temperature (1.5 h) and was poured in a thin stream into hydrochloric acid (3 N, 200 ml). The pH of the mixture was then adjusted to neutral using NaHCO3. After this it was filtered and the filtrate was evaporated under reduced pressure (11 torr) to obtain the title compound (yield; 15 g, 90%); m.p. 354–355 K. Colorless crystals of (I) suitable for X-ray diffraction were grown from MeOH by slow evaporation at room temperature.

Refinement top

H atoms were positioned geometrically, with C—H = 0.93, 0.97, and 0.96 Å for aromatic, methylene and methyl H, and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C), where x = 1.5 for methyl H, and x = 1.2 for all other H atoms.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: APEX2 (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: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. ORTEP-3 (Farrugia, 1997) drawing of (I) with the atom numbering scheme. The thermal ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. The unit cell packing of (I) (Spek, 2003) showing the intermolecular hydrogen bonds resulting in dimers.
1-Ethyl-1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide top
Crystal data top
C10H11NO3SZ = 2
Mr = 225.26F(000) = 236
Triclinic, P1Dx = 1.454 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.0272 (3) ÅCell parameters from 1760 reflections
b = 8.0448 (4) Åθ = 2.2–28.7°
c = 9.5880 (4) ŵ = 0.30 mm−1
α = 99.124 (3)°T = 296 K
β = 95.075 (3)°Prismatic, colourless
γ = 104.092 (3)°0.15 × 0.12 × 0.10 mm
V = 514.48 (4) Å3
Data collection top
Bruker Kappa APEXII CCD
diffractometer		2608 independent reflections
Radiation source: fine-focus sealed tube1760 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.036
Detector resolution: 7.40 pixels mm-1θmax = 28.7°, θmin = 2.2°
ω scansh = −9→9
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		k = −10→10
Tmin = 0.965, Tmax = 0.988l = −12→12
11339 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)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.107H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0488P)2 + 0.0854P]
where P = (Fo2 + 2Fc2)/3
2608 reflections(Δ/σ)max < 0.001
136 parametersΔρmax = 0.29 e Å−3
0 restraintsΔρmin = −0.26 e Å−3
Crystal data top
C10H11NO3Sγ = 104.092 (3)°
Mr = 225.26V = 514.48 (4) Å3
Triclinic, P1Z = 2
a = 7.0272 (3) ÅMo Kα radiation
b = 8.0448 (4) ŵ = 0.30 mm−1
c = 9.5880 (4) ÅT = 296 K
α = 99.124 (3)°0.15 × 0.12 × 0.10 mm
β = 95.075 (3)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer		2608 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		1760 reflections with I > 2σ(I)
Tmin = 0.965, Tmax = 0.988Rint = 0.036
11339 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.107H-atom parameters constrained
S = 1.02Δρmax = 0.29 e Å−3
2608 reflectionsΔρmin = −0.26 e Å−3
136 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
S10.32887 (8)0.16467 (6)0.90938 (5)0.04169 (17)
O10.5349 (2)0.18066 (19)0.90570 (14)0.0531 (4)
O20.2664 (3)0.2196 (2)1.04236 (14)0.0670 (5)
O30.2248 (2)−0.25167 (19)0.63616 (17)0.0632 (4)
N10.2390 (2)0.2638 (2)0.79263 (15)0.0415 (4)
C10.2558 (3)0.2075 (2)0.64688 (17)0.0328 (4)
C20.2726 (3)0.3249 (3)0.5533 (2)0.0429 (5)
H20.27460.44060.58610.051*
C30.2864 (3)0.2688 (3)0.4118 (2)0.0489 (5)
H30.29590.34750.34980.059*
C40.2862 (3)0.1000 (3)0.3604 (2)0.0485 (5)
H40.29820.06510.26510.058*
C50.2684 (3)−0.0161 (3)0.45077 (19)0.0420 (5)
H50.2679−0.13100.41600.050*
C60.2509 (2)0.0337 (2)0.59449 (17)0.0329 (4)
C70.2276 (3)−0.1022 (2)0.6829 (2)0.0389 (4)
C80.2024 (3)−0.0522 (3)0.8374 (2)0.0445 (5)
H8A0.2512−0.12850.89190.053*
H8B0.0627−0.06870.84540.053*
C90.2066 (3)0.4367 (3)0.8431 (2)0.0461 (5)
H9A0.29510.52390.80320.055*
H9B0.23780.46640.94610.055*
C10−0.0036 (3)0.4394 (3)0.8011 (3)0.0575 (6)
H10A−0.01970.55320.83540.086*
H10B−0.09140.35450.84200.086*
H10C−0.03410.41200.69920.086*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0517 (3)0.0444 (3)0.0303 (2)0.0137 (2)0.00127 (19)0.01149 (19)
O10.0444 (9)0.0558 (9)0.0541 (8)0.0071 (7)−0.0081 (6)0.0135 (7)
O20.0971 (13)0.0800 (12)0.0318 (7)0.0339 (10)0.0142 (8)0.0136 (7)
O30.0782 (12)0.0343 (9)0.0810 (11)0.0192 (8)0.0145 (9)0.0127 (7)
N10.0633 (11)0.0387 (9)0.0299 (7)0.0260 (8)0.0075 (7)0.0082 (6)
C10.0347 (10)0.0366 (10)0.0302 (8)0.0141 (8)0.0044 (7)0.0083 (7)
C20.0504 (12)0.0408 (11)0.0434 (10)0.0167 (9)0.0083 (9)0.0163 (8)
C30.0492 (13)0.0673 (15)0.0394 (10)0.0197 (11)0.0106 (9)0.0273 (10)
C40.0436 (12)0.0748 (16)0.0305 (9)0.0224 (10)0.0055 (8)0.0083 (9)
C50.0374 (11)0.0459 (12)0.0407 (10)0.0152 (9)0.0000 (8)−0.0022 (8)
C60.0297 (9)0.0366 (11)0.0337 (9)0.0118 (8)0.0026 (7)0.0066 (7)
C70.0332 (10)0.0337 (11)0.0498 (11)0.0092 (8)0.0013 (8)0.0095 (8)
C80.0446 (12)0.0431 (12)0.0485 (11)0.0080 (9)0.0024 (9)0.0237 (9)
C90.0618 (14)0.0334 (11)0.0423 (10)0.0152 (10)0.0087 (9)−0.0004 (8)
C100.0615 (15)0.0474 (14)0.0693 (14)0.0239 (11)0.0180 (11)0.0075 (11)
Geometric parameters (Å, º) top
S1—O21.4244 (14)C4—H40.9300
S1—O11.4260 (14)C5—C61.398 (2)
S1—N11.6405 (15)C5—H50.9300
S1—C81.750 (2)C6—C71.473 (2)
O3—C71.210 (2)C7—C81.510 (3)
N1—C11.424 (2)C8—H8A0.9700
N1—C91.477 (2)C8—H8B0.9700
C1—C21.395 (2)C9—C101.503 (3)
C1—C61.400 (2)C9—H9A0.9700
C2—C31.380 (3)C9—H9B0.9700
C2—H20.9300C10—H10A0.9600
C3—C41.368 (3)C10—H10B0.9600
C3—H30.9300C10—H10C0.9600
C4—C51.363 (3)
O2—S1—O1118.03 (10)C5—C6—C1119.07 (16)
O2—S1—N1107.40 (9)C5—C6—C7117.38 (17)
O1—S1—N1111.71 (9)C1—C6—C7123.54 (16)
O2—S1—C8110.60 (10)O3—C7—C6122.76 (18)
O1—S1—C8107.58 (9)O3—C7—C8119.04 (17)
N1—S1—C8100.05 (8)C6—C7—C8118.20 (16)
C1—N1—C9121.18 (14)C7—C8—S1112.13 (13)
C1—N1—S1117.15 (12)C7—C8—H8A109.2
C9—N1—S1118.59 (12)S1—C8—H8A109.2
C2—C1—C6119.03 (16)C7—C8—H8B109.2
C2—C1—N1120.08 (16)S1—C8—H8B109.2
C6—C1—N1120.87 (15)H8A—C8—H8B107.9
C3—C2—C1119.70 (18)N1—C9—C10111.54 (17)
C3—C2—H2120.2N1—C9—H9A109.3
C1—C2—H2120.2C10—C9—H9A109.3
C4—C3—C2121.64 (18)N1—C9—H9B109.3
C4—C3—H3119.2C10—C9—H9B109.3
C2—C3—H3119.2H9A—C9—H9B108.0
C5—C4—C3119.13 (18)C9—C10—H10A109.5
C5—C4—H4120.4C9—C10—H10B109.5
C3—C4—H4120.4H10A—C10—H10B109.5
C4—C5—C6121.41 (18)C9—C10—H10C109.5
C4—C5—H5119.3H10A—C10—H10C109.5
C6—C5—H5119.3H10B—C10—H10C109.5
O2—S1—N1—C1−170.18 (14)C4—C5—C6—C7178.61 (17)
O1—S1—N1—C158.92 (16)C2—C1—C6—C51.7 (3)
C8—S1—N1—C1−54.70 (16)N1—C1—C6—C5−179.84 (16)
O2—S1—N1—C929.41 (18)C2—C1—C6—C7−178.16 (17)
O1—S1—N1—C9−101.49 (15)N1—C1—C6—C70.3 (3)
C8—S1—N1—C9144.89 (15)C5—C6—C7—O30.5 (3)
C9—N1—C1—C29.9 (3)C1—C6—C7—O3−179.56 (17)
S1—N1—C1—C2−149.95 (15)C5—C6—C7—C8−178.23 (15)
C9—N1—C1—C6−168.48 (17)C1—C6—C7—C81.7 (3)
S1—N1—C1—C631.6 (2)O3—C7—C8—S1149.47 (16)
C6—C1—C2—C3−0.7 (3)C6—C7—C8—S1−31.7 (2)
N1—C1—C2—C3−179.18 (17)O2—S1—C8—C7166.56 (13)
C1—C2—C3—C4−0.8 (3)O1—S1—C8—C7−63.23 (15)
C2—C3—C4—C51.2 (3)N1—S1—C8—C753.53 (15)
C3—C4—C5—C6−0.2 (3)C1—N1—C9—C1075.8 (2)
C4—C5—C6—C1−1.3 (3)S1—N1—C9—C10−124.64 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O3i0.932.563.478 (3)169
C8—H8A···O1ii0.972.503.388 (3)152
C9—H9B···O20.972.362.855 (3)111
Symmetry codes: (i) x, y+1, z; (ii) −x+1, −y, −z+2.

Experimental details

Crystal data
Chemical formulaC10H11NO3S
Mr225.26
Crystal system, space groupTriclinic, P1
Temperature (K)296
a, b, c (Å)7.0272 (3), 8.0448 (4), 9.5880 (4)
α, β, γ (°)99.124 (3), 95.075 (3), 104.092 (3)
V (Å3)514.48 (4)
Z2
Radiation typeMo Kα
µ (mm−1)0.30
Crystal size (mm)0.15 × 0.12 × 0.10
Data collection
DiffractometerBruker Kappa APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.965, 0.988
No. of measured, independent and
observed [I > 2σ(I)] reflections		11339, 2608, 1760
Rint0.036
(sin θ/λ)max (Å−1)0.675
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.107, 1.02
No. of reflections2608
No. of parameters136
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.29, −0.26

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003), WinGX (Farrugia, 1999) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O3i0.932.563.478 (3)169
C8—H8A···O1ii0.972.503.388 (3)152
C9—H9B···O20.972.362.855 (3)111
Symmetry codes: (i) x, y+1, z; (ii) −x+1, −y, −z+2.
 

Acknowledgements

The authors acknowledge the Higher Education Commission, Islamabad, Pakistan, and Bana International, Karachi, Pakistan, for funding the purchase of the diffractometer and for technical support, respectively.

References

First citationBruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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ISSN: 2056-9890
Volume 64| Part 3| March 2008| Page o558
doi:10.1107/S1600536808003504
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