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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 7| July 2008| Page o1270
doi:10.1107/S1600536808017510

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

Muhammad Shafiq,a M. Nawaz Tahir,b* Islam Ullah Khan,a Saeed Ahmadc and Waseeq Ahmad Siddiquid

aDepartment of Chemistry, Government College University, Lahore, Pakistan, bDepartment of Physics, University of Sargodha, Sagrodha, Pakistan, cDepartment of Chemistry, University of Science and Technology Bannu, Bannu, Pakistan, and dDepartment of Chemistry, University of Sargodha, Sagrodha, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 8 June 2008; accepted 10 June 2008; online 13 June 2008)

In the mol­ecule of the title compound, C10H9Br2NO3S, the S atom is four-coordinated in distorted tetra­hedral configuration. The heterocyclic thia­zine ring adopts a twist conformation. An intra­molecular C—H⋯O hydrogen bond results in the formation of a non-planar five-membered ring. In the crystal structure, inter­molecular C—H⋯O hydrogen bonds link the mol­ecules into infinite chains along the c axis.

Related literature

For related literature, see: Franzén (2000[Franzén, R. G. (2000). J. Comb. Chem. 2, 195-214.]); Misu & Togo (2003[Misu, Y. & Togo, H. (2003). Org. Biol. Chem. 1, 1342-1346.]); Shafiq et al. (2008[Shafiq, M., Khan, I. U., Tahir, M. N. & Siddiqui, W. A. (2008). Acta Cryst. E64, o558.]); Tahir et al. (2008[Tahir, M. N., Shafiq, M., Khan, I. U., Siddiqui, W. A. & Arshad, M. N. (2008). Acta Cryst. E64, o557.]). For ring puckering parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data

  • C10H9Br2NO3S

  • Mr = 383.06

  • Monoclinic, P 21 /c

  • a = 7.7979 (5) Å

  • b = 11.9645 (7) Å

  • c = 13.1231 (8) Å

  • β = 95.374 (3)°

  • V = 1218.98 (13) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 6.82 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 = 0.400, Tmax = 0.508

  • 14754 measured reflections

  • 3281 independent reflections

  • 1708 reflections with I > 2σ(I)

  • Rint = 0.059
Refinement

  • R[F2 > 2σ(F2)] = 0.066

  • wR(F2) = 0.221

  • S = 1.02

  • 3281 reflections

  • 154 parameters

  • H-atom parameters constrained

  • Δρmax = 1.27 e Å−3

  • Δρmin = −1.61 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C2—H2⋯O1i 0.93 2.52 3.390 (10) 157
C9—H9A⋯O1 0.97 2.38 2.876 (11) 111
Symmetry code: (i) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc. Madison, Wisconsin, USA.]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. 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/S1600536808017510/hk2472sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808017510/hk2472Isup2.hkl

checkCIF report


Comment top

The synthesis of heterocyclic system is of continuing interest because a large number of biologically active molecules contain heterocyclic rings (Franzén, 2000). 2,1-Benzothiazine is a relatively unexplored ring system with respect to both its synthesis and biological activity, in which it belongs to an important heterocyclic class of compounds, although it finds a number of applications in medicinal chemistry. The derivatives of 2,1-benzothiazine are used as drugs for heart diseases and also show lipoxygenase inhibition activity (Misu & Togo, 2003). Recently we have reported the crystal structures of 1-ethyl-1H -2,1-benzothiazin-4(3H) one 2,2-dioxide, (II) (Shafiq et al., 2008) and 1-methyl-1H-2,1-benzothiazin-4(3H) one 2,2-dioxide, (III) (Tahir et al., 2008), in which they contain the same heterocyclic ring. We report herein the syntesis and crystal structure of the title compound, (I), which is obtained from the bromination of (II).

In the molecule of (I) (Fig. 1), the bond lengths and angles are within normal ranges, which are comparable with the corresponding values in (II). The S1-N1 [1.617 (6) Å], S1-C8 [1.792 (8) Å] and C7-C8 [1.540 (11) Å] bonds in (I) are reported as 1.6405 (15), 1.750 (2) and 1.510 (3) Å, respectively, in (II). The S atom is four-coordinated in distorted tetrahedral configuration (Table 1) by one N and one C atoms of the heterocyclic ring and two O atoms. Ring A (C1-C6) is, of course, planar, and it is oriented with respect to (S1/O1/O2) and (C8/Br1/Br2) planes at dihedral angles of 78.44 (32)° and 77.79 (28)°, respectively. Ring B (S1/N1/C1/C6-C8) adopts twisted conformation, having total puckering amplitude, QT, of 0.763 (2) Å (Cremer & Pople, 1975). The intra- molecular C-H···O hydrogen bond (Table 2) results in the formation of a non-planar five-membered ring C (O1/S1/N1/C9/H9A).

In the crystal structure, intermolecular C-H···O hydrogen bonds (Table 2) link the molecules into infinine chains along the c axis (Fig. 2), in which they may be effective in the stabilization of the structure.

Related literature top

For related literature, see: Franzén (2000); Misu & Togo (2003); Shafiq et al. (2008); Tahir et al. (2008). For ring puckering parameters, see: Cremer & Pople (1975).

Experimental top

Compound (I) was prepared by the reaction of (II) (34.0 mg, 0.15 mmol), N-bromosuccinimide (57.0 mg, 0.32 mmol) and dibenzoyl peroxide (2.1 mg, 0.009 mmol) in CCl4 (8 ml) by heating under reflux for 2 h. Crystals suitable for X-ray analysis were obtained by evaporating the solvent slowly at room temperature for about 7 d (m.p. 394-395 K).

Refinement top

The highest peak and deepest hole in the final difference electron density map are located 1.27 and 1.61 Å from Br1 and Br2 atoms, respectively. 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. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen bond is shown as dashed line.
[Figure 2] Fig. 2. A packing diagram of (I). Hydrogen bonds are shown as dashed lines.
3,3-Dibromo-1-ethyl-1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide top
Crystal data top
C10H9Br2NO3SF(000) = 744
Mr = 383.06Dx = 2.087 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 708 reflections
a = 7.7979 (5) Åθ = 2.3–29.2°
b = 11.9645 (7) ŵ = 6.82 mm−1
c = 13.1231 (8) ÅT = 296 K
β = 95.374 (3)°Prismatic, red
V = 1218.98 (13) Å30.15 × 0.12 × 0.10 mm
Z = 4
Data collection top
Bruker KappaAPEXII CCD
diffractometer		3281 independent reflections
Radiation source: fine-focus sealed tube1708 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.059
Detector resolution: 7.40 pixels mm-1θmax = 29.2°, θmin = 2.3°
ω scansh = −8→10
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		k = −16→15
Tmin = 0.400, Tmax = 0.508l = −17→18
14754 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)] = 0.066Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.221H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.1081P)2 + 4.0099P]
where P = (Fo2 + 2Fc2)/3
3281 reflections(Δ/σ)max < 0.001
154 parametersΔρmax = 1.27 e Å−3
0 restraintsΔρmin = −1.61 e Å−3
Crystal data top
C10H9Br2NO3SV = 1218.98 (13) Å3
Mr = 383.06Z = 4
Monoclinic, P21/cMo Kα radiation
a = 7.7979 (5) ŵ = 6.82 mm−1
b = 11.9645 (7) ÅT = 296 K
c = 13.1231 (8) Å0.15 × 0.12 × 0.10 mm
β = 95.374 (3)°
Data collection top
Bruker KappaAPEXII CCD
diffractometer		3281 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		1708 reflections with I > 2σ(I)
Tmin = 0.400, Tmax = 0.508Rint = 0.059
14754 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0660 restraints
wR(F2) = 0.221H-atom parameters constrained
S = 1.03Δρmax = 1.27 e Å−3
3281 reflectionsΔρmin = −1.61 e Å−3
154 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
Br10.97364 (12)0.08723 (8)0.18987 (7)0.0520 (3)
Br20.71557 (15)−0.05878 (9)0.04712 (7)0.0616 (4)
S10.5854 (3)0.09863 (16)0.20346 (14)0.0353 (5)
O10.5802 (9)0.1912 (5)0.1362 (5)0.0554 (17)
O20.4378 (7)0.0280 (5)0.2029 (4)0.0427 (14)
O30.7951 (9)−0.1813 (5)0.2399 (5)0.0521 (16)
N10.6503 (9)0.1398 (5)0.3180 (5)0.0346 (15)
C10.6964 (10)0.0579 (6)0.3926 (6)0.0296 (16)
C20.6905 (11)0.0854 (7)0.4974 (6)0.0405 (19)
H20.65690.15650.51630.049*
C30.7351 (12)0.0054 (9)0.5708 (7)0.051 (2)
H30.73370.02420.63950.062*
C40.7809 (13)−0.0996 (8)0.5460 (7)0.054 (2)
H40.8088−0.15230.59700.064*
C50.7859 (11)−0.1275 (7)0.4450 (6)0.044 (2)
H50.8149−0.20010.42780.053*
C60.7480 (10)−0.0488 (6)0.3675 (6)0.0319 (16)
C70.7694 (10)−0.0849 (6)0.2634 (6)0.0347 (17)
C80.7569 (10)0.0054 (7)0.1794 (6)0.0348 (17)
C90.6490 (12)0.2600 (6)0.3460 (7)0.047 (2)
H9A0.59980.30230.28730.056*
H9B0.57450.27000.40050.056*
C100.8162 (14)0.3057 (8)0.3789 (9)0.065 (3)
H10A0.80470.38320.39580.098*
H10B0.89020.29840.32480.098*
H10C0.86510.26570.43810.098*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0447 (6)0.0622 (6)0.0509 (6)−0.0139 (4)0.0134 (4)−0.0031 (4)
Br20.0757 (8)0.0722 (7)0.0374 (5)−0.0052 (5)0.0077 (5)−0.0101 (4)
S10.0405 (12)0.0358 (10)0.0293 (10)0.0021 (9)0.0010 (8)0.0063 (8)
O10.069 (4)0.048 (3)0.049 (4)0.003 (3)−0.001 (3)0.021 (3)
O20.032 (3)0.053 (4)0.043 (3)−0.010 (3)0.005 (3)−0.007 (3)
O30.074 (5)0.035 (3)0.047 (4)0.009 (3)0.010 (3)−0.009 (3)
N10.049 (4)0.026 (3)0.028 (3)0.002 (3)0.000 (3)−0.001 (2)
C10.027 (4)0.031 (4)0.030 (4)−0.006 (3)0.000 (3)−0.002 (3)
C20.041 (5)0.050 (5)0.031 (4)−0.003 (4)0.001 (4)−0.012 (4)
C30.057 (6)0.066 (6)0.032 (4)−0.012 (5)0.005 (4)−0.005 (4)
C40.056 (6)0.060 (6)0.043 (5)−0.004 (5)−0.003 (4)0.020 (4)
C50.046 (5)0.044 (5)0.044 (5)0.000 (4)0.009 (4)0.014 (4)
C60.030 (4)0.034 (4)0.033 (4)−0.001 (3)0.006 (3)−0.004 (3)
C70.031 (4)0.035 (4)0.038 (4)0.001 (3)0.000 (3)0.000 (3)
C80.037 (5)0.040 (4)0.027 (4)−0.008 (4)0.004 (3)−0.004 (3)
C90.058 (6)0.026 (4)0.056 (5)0.013 (4)0.005 (4)0.000 (4)
C100.069 (7)0.036 (5)0.091 (8)−0.011 (5)0.008 (6)−0.011 (5)
Geometric parameters (Å, º) top
Br1—C81.947 (8)C3—H30.9300
Br2—C81.898 (7)C4—C51.371 (13)
S1—O11.415 (6)C4—H40.9300
S1—O21.428 (6)C5—C61.397 (11)
S1—N11.617 (6)C5—H50.9300
S1—C81.792 (8)C6—C71.457 (11)
O3—C71.215 (9)C7—C81.540 (11)
N1—C11.408 (9)C9—C101.442 (14)
N1—C91.486 (9)C9—H9A0.9700
C1—C61.388 (10)C9—H9B0.9700
C1—C21.418 (11)C10—H10A0.9600
C2—C31.380 (13)C10—H10B0.9600
C2—H20.9300C10—H10C0.9600
C3—C41.354 (14)
O1—S1—O2119.0 (4)C1—C6—C5119.6 (7)
O1—S1—N1109.3 (4)C1—C6—C7123.8 (7)
O2—S1—N1111.5 (3)C5—C6—C7116.6 (7)
O1—S1—C8110.8 (4)O3—C7—C6123.7 (7)
O2—S1—C8104.2 (4)O3—C7—C8119.1 (7)
N1—S1—C8100.3 (3)C6—C7—C8117.3 (6)
C1—N1—C9120.6 (6)C7—C8—S1108.0 (5)
C1—N1—S1118.2 (5)C7—C8—Br2111.4 (5)
C9—N1—S1121.1 (5)S1—C8—Br2110.3 (4)
C6—C1—N1122.4 (7)C7—C8—Br1107.8 (5)
C6—C1—C2118.7 (7)S1—C8—Br1109.4 (4)
N1—C1—C2118.9 (7)Br2—C8—Br1109.9 (4)
C3—C2—C1119.1 (8)C10—C9—N1114.5 (7)
C3—C2—H2120.4C10—C9—H9A108.6
C1—C2—H2120.4N1—C9—H9A108.6
C4—C3—C2122.1 (8)C10—C9—H9B108.6
C4—C3—H3119.0N1—C9—H9B108.6
C2—C3—H3119.0H9A—C9—H9B107.6
C3—C4—C5119.4 (8)C9—C10—H10A109.5
C3—C4—H4120.3C9—C10—H10B109.5
C5—C4—H4120.3H10A—C10—H10B109.5
C4—C5—C6121.1 (8)C9—C10—H10C109.5
C4—C5—H5119.5H10A—C10—H10C109.5
C6—C5—H5119.5H10B—C10—H10C109.5
O1—S1—N1—C1−167.9 (6)C1—C6—C7—O3−171.2 (8)
O2—S1—N1—C158.5 (7)C5—C6—C7—O310.1 (12)
C8—S1—N1—C1−51.4 (6)C1—C6—C7—C88.3 (11)
O1—S1—N1—C916.6 (8)C5—C6—C7—C8−170.4 (7)
O2—S1—N1—C9−117.0 (7)O3—C7—C8—S1139.1 (7)
C8—S1—N1—C9133.1 (7)C6—C7—C8—S1−40.4 (8)
C9—N1—C1—C6−160.8 (7)O3—C7—C8—Br217.8 (10)
S1—N1—C1—C623.7 (10)C6—C7—C8—Br2−161.7 (6)
C9—N1—C1—C219.1 (11)O3—C7—C8—Br1−102.8 (8)
S1—N1—C1—C2−156.4 (6)C6—C7—C8—Br177.7 (7)
C6—C1—C2—C3−0.3 (12)O1—S1—C8—C7173.0 (5)
N1—C1—C2—C3179.8 (8)O2—S1—C8—C7−57.8 (6)
C1—C2—C3—C4−1.5 (14)N1—S1—C8—C757.7 (6)
C2—C3—C4—C51.0 (15)O1—S1—C8—Br2−65.0 (5)
C3—C4—C5—C61.4 (14)O2—S1—C8—Br264.1 (4)
N1—C1—C6—C5−177.6 (7)N1—S1—C8—Br2179.6 (4)
C2—C1—C6—C52.6 (11)O1—S1—C8—Br155.9 (5)
N1—C1—C6—C73.7 (12)O2—S1—C8—Br1−174.9 (4)
C2—C1—C6—C7−176.1 (8)N1—S1—C8—Br1−59.4 (4)
C4—C5—C6—C1−3.2 (13)C1—N1—C9—C1065.8 (11)
C4—C5—C6—C7175.6 (8)S1—N1—C9—C10−118.8 (8)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O1i0.932.523.390 (10)157
C9—H9A···O10.972.382.876 (11)111
Symmetry code: (i) x, −y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC10H9Br2NO3S
Mr383.06
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)7.7979 (5), 11.9645 (7), 13.1231 (8)
β (°) 95.374 (3)
V (Å3)1218.98 (13)
Z4
Radiation typeMo Kα
µ (mm−1)6.82
Crystal size (mm)0.15 × 0.12 × 0.10
Data collection
DiffractometerBruker KappaAPEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.400, 0.508
No. of measured, independent and
observed [I > 2σ(I)] reflections		14754, 3281, 1708
Rint0.059
(sin θ/λ)max (Å−1)0.686
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.066, 0.221, 1.03
No. of reflections3281
No. of parameters154
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)1.27, −1.61

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).

Selected geometric parameters (Å, º) top
S1—O11.415 (6)S1—N11.617 (6)
S1—O21.428 (6)S1—C81.792 (8)
O1—S1—O2119.0 (4)O1—S1—C8110.8 (4)
O1—S1—N1109.3 (4)O2—S1—C8104.2 (4)
O2—S1—N1111.5 (3)N1—S1—C8100.3 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O1i0.932.523.390 (10)157.00
C9—H9A···O10.972.382.876 (11)111.00
Symmetry code: (i) x, −y+1/2, z+1/2.
 

Acknowledgements

Muhammad Shafiq greatfully acknowledges the Higher Education Commision, Islamabad, Pakistan, for providing a Scholarship under the Indigenous PhD Program.

References

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 First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
 First citationFarrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838.  CrossRef CAS IUCr Journals Google Scholar
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ISSN: 2056-9890
Volume 64| Part 7| July 2008| Page o1270
doi:10.1107/S1600536808017510
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