organic compounds
6-Bromo-3,3-dichloro-1-methyl-1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide
aGovernment College University, Department of Chemistry, Lahore, Pakistan, and bUniversity of Sargodha, Department of Physics, Sargodha, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com
The monomeric title compound, C9H6BrCl2NO3S, has an envelope-shaped thiazine ring with the S atom 0.879 (9) Å out of the mean square plane of the envelope. The π–π distances between the centroids of the heterocyclic rings are 4.191 (5) and 4.110 (5) Å. The closest intermolecular interactions between the O atoms of the carbonyl and sulfonyl groups with Br and Cl atoms are 2.987 (7) and 2.992 (8) Å, respectively.
Related literature
For halogination (chlorination or bromination) of 1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide, see: Shafiq et al. (2008); Shafiq, Tahir, Khan, Ahmad et al. (2009); Shafiq, Tahir, Khan, Arshad & Asghar (2009); Shafiq, Tahir, Khan, Arshad & Safdar (2009).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2007); cell SAINT (Bruker, 2007); data reduction: SAINT; 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, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON.
Supporting information
10.1107/S1600536809019291/ng2585sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809019291/ng2585Isup2.hkl
The title compound was prepared following the method as reported in Shafiq, Tahir, Khan, Ahmad et al. (2009). A mixture was prepared from 6-bromo-1-methyl-1 H-2,1-benzothiazin-4(3H)-one 2,2-dioxide (250 mg, 0.862 mmol) (Shafiq, Tahir, Khan, Arshad & Asghar, 2009), N-Chloro Succinamide (225.85 mg, 1.724 mmol) and Benzoylperoxide (11.99 mg, 0.0495 mmol) in Carbon Tetra Chloride (10 ml). The mixture was heated under reflux (353 K) for two h. CCl4 was evaporated under reduced pressure and the residue obtained was recrystallized from mixture of ethanol:ethyl acetate (1:1).
H-atoms were positioned geometrically, with C—H = 0.93 and 0.96 Å for aryl and methyl H, respectively and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C), where x = 1.2 for aryl and 1.5 for methyl H atoms.
In difference Fourier map, three peaks of electron density 2.07, 1.87 and 1.86 e Å-3 exist which are at distance of 1.09, 1.09 and 1.42 Å from the BR1, BR1 and CL2, respectively.
Data collection: APEX2 (Bruker, 2007); cell
SAINT (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, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).C9H6BrCl2NO3S | F(000) = 704 |
Mr = 359.02 | Dx = 1.908 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 2317 reflections |
a = 7.0285 (9) Å | θ = 2.7–25.5° |
b = 14.865 (2) Å | µ = 3.88 mm−1 |
c = 11.9739 (18) Å | T = 296 K |
β = 92.418 (5)° | Needle, yellow |
V = 1249.9 (3) Å3 | 0.26 × 0.14 × 0.12 mm |
Z = 4 |
Bruker Kappa-APEXII CCD diffractometer | 2317 independent reflections |
Radiation source: fine-focus sealed tube | 1595 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.048 |
Detector resolution: 7.80 pixels mm-1 | θmax = 25.5°, θmin = 2.7° |
ω scans | h = −8→8 |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | k = −17→18 |
Tmin = 0.529, Tmax = 0.626 | l = −14→14 |
11409 measured reflections |
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)] = 0.082 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.249 | H-atom parameters constrained |
S = 1.09 | w = 1/[σ2(Fo2) + (0.1412P)2 + 3.7083P] where P = (Fo2 + 2Fc2)/3 |
2317 reflections | (Δ/σ)max < 0.000 |
155 parameters | Δρmax = 2.07 e Å−3 |
0 restraints | Δρmin = −0.46 e Å−3 |
C9H6BrCl2NO3S | V = 1249.9 (3) Å3 |
Mr = 359.02 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 7.0285 (9) Å | µ = 3.88 mm−1 |
b = 14.865 (2) Å | T = 296 K |
c = 11.9739 (18) Å | 0.26 × 0.14 × 0.12 mm |
β = 92.418 (5)° |
Bruker Kappa-APEXII CCD diffractometer | 2317 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | 1595 reflections with I > 2σ(I) |
Tmin = 0.529, Tmax = 0.626 | Rint = 0.048 |
11409 measured reflections |
R[F2 > 2σ(F2)] = 0.082 | 0 restraints |
wR(F2) = 0.249 | H-atom parameters constrained |
S = 1.09 | Δρmax = 2.07 e Å−3 |
2317 reflections | Δρmin = −0.46 e Å−3 |
155 parameters |
Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles |
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. |
x | y | z | Uiso*/Ueq | ||
Br1 | 0.74792 (15) | 0.56286 (7) | 0.70311 (9) | 0.0672 (4) | |
Cl1 | 0.7616 (5) | 0.06220 (15) | 0.4704 (3) | 0.0880 (13) | |
Cl2 | 0.4591 (4) | 0.1801 (2) | 0.3853 (3) | 0.0812 (11) | |
S1 | 0.8566 (4) | 0.20955 (15) | 0.3260 (2) | 0.0605 (9) | |
O1 | 1.0377 (10) | 0.2088 (5) | 0.3836 (7) | 0.073 (3) | |
O2 | 0.8231 (13) | 0.1591 (5) | 0.2266 (7) | 0.092 (3) | |
O3 | 0.7221 (14) | 0.2086 (5) | 0.6253 (6) | 0.086 (3) | |
N1 | 0.7709 (10) | 0.3103 (5) | 0.3049 (5) | 0.047 (3) | |
C1 | 0.7428 (11) | 0.3339 (5) | 0.5055 (7) | 0.041 (2) | |
C2 | 0.7384 (11) | 0.3928 (6) | 0.5972 (7) | 0.046 (3) | |
C3 | 0.7472 (11) | 0.4837 (5) | 0.5800 (7) | 0.045 (3) | |
C4 | 0.7598 (12) | 0.5177 (5) | 0.4732 (8) | 0.050 (3) | |
C5 | 0.7673 (12) | 0.4611 (5) | 0.3832 (7) | 0.046 (3) | |
C6 | 0.7602 (10) | 0.3681 (5) | 0.3979 (6) | 0.037 (2) | |
C7 | 0.7331 (16) | 0.3430 (8) | 0.1909 (7) | 0.069 (4) | |
C8 | 0.7023 (14) | 0.1722 (5) | 0.4321 (8) | 0.055 (3) | |
C9 | 0.7248 (12) | 0.2370 (6) | 0.5326 (7) | 0.048 (3) | |
H2 | 0.72951 | 0.37007 | 0.66913 | 0.0547* | |
H4 | 0.76319 | 0.57957 | 0.46234 | 0.0596* | |
H5 | 0.77715 | 0.48484 | 0.31182 | 0.0551* | |
H7A | 0.83703 | 0.38008 | 0.16917 | 0.1043* | |
H7B | 0.71969 | 0.29273 | 0.14086 | 0.1043* | |
H7C | 0.61767 | 0.37762 | 0.18786 | 0.1043* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br1 | 0.0732 (8) | 0.0623 (7) | 0.0664 (7) | −0.0014 (4) | 0.0073 (5) | −0.0331 (5) |
Cl1 | 0.140 (3) | 0.0300 (12) | 0.094 (2) | 0.0046 (13) | 0.006 (2) | 0.0024 (12) |
Cl2 | 0.0585 (16) | 0.098 (2) | 0.086 (2) | −0.0217 (14) | −0.0094 (14) | −0.0057 (16) |
S1 | 0.0730 (18) | 0.0455 (13) | 0.0641 (15) | 0.0053 (11) | 0.0174 (13) | −0.0116 (11) |
O1 | 0.047 (4) | 0.076 (5) | 0.096 (5) | 0.017 (3) | 0.005 (4) | −0.008 (4) |
O2 | 0.136 (7) | 0.063 (5) | 0.078 (5) | −0.002 (5) | 0.028 (5) | −0.035 (4) |
O3 | 0.164 (8) | 0.048 (4) | 0.046 (4) | 0.001 (4) | 0.006 (4) | 0.012 (3) |
N1 | 0.075 (5) | 0.036 (4) | 0.031 (4) | 0.003 (3) | 0.005 (3) | −0.002 (3) |
C1 | 0.045 (4) | 0.034 (4) | 0.043 (4) | 0.000 (3) | 0.002 (3) | −0.001 (3) |
C2 | 0.056 (5) | 0.048 (5) | 0.033 (4) | −0.002 (4) | 0.001 (4) | −0.001 (4) |
C3 | 0.051 (5) | 0.034 (4) | 0.049 (5) | 0.000 (3) | −0.003 (4) | −0.014 (4) |
C4 | 0.057 (5) | 0.031 (4) | 0.061 (6) | 0.003 (4) | 0.008 (4) | 0.003 (4) |
C5 | 0.068 (6) | 0.034 (4) | 0.037 (4) | 0.001 (4) | 0.005 (4) | 0.001 (3) |
C6 | 0.041 (4) | 0.042 (4) | 0.029 (4) | 0.003 (3) | 0.002 (3) | −0.001 (3) |
C7 | 0.102 (8) | 0.073 (7) | 0.033 (5) | 0.014 (6) | 0.002 (5) | −0.001 (4) |
C8 | 0.082 (7) | 0.028 (4) | 0.054 (5) | −0.006 (4) | 0.002 (5) | −0.001 (4) |
C9 | 0.059 (5) | 0.041 (4) | 0.044 (5) | 0.000 (4) | −0.001 (4) | 0.003 (4) |
Br1—C3 | 1.886 (8) | C1—C9 | 1.483 (12) |
Cl1—C8 | 1.744 (8) | C2—C3 | 1.369 (12) |
Cl2—C8 | 1.780 (10) | C3—C4 | 1.381 (12) |
S1—O1 | 1.422 (8) | C4—C5 | 1.370 (12) |
S1—O2 | 1.418 (8) | C5—C6 | 1.395 (11) |
S1—N1 | 1.630 (8) | C8—C9 | 1.544 (12) |
S1—C8 | 1.793 (10) | C2—H2 | 0.9300 |
O3—C9 | 1.189 (11) | C4—H4 | 0.9300 |
N1—C6 | 1.411 (10) | C5—H5 | 0.9300 |
N1—C7 | 1.463 (11) | C7—H7A | 0.9600 |
C1—C2 | 1.406 (12) | C7—H7B | 0.9600 |
C1—C6 | 1.395 (11) | C7—H7C | 0.9600 |
Br1···O3i | 2.987 (7) | C3···C4ii | 3.593 (12) |
Br1···C5ii | 3.741 (9) | C3···C4iii | 3.550 (12) |
Br1···C5iii | 3.620 (9) | C3···C5iii | 3.519 (11) |
Br1···H7Cii | 3.0600 | C4···O2ix | 3.219 (12) |
Cl1···O1 | 3.125 (8) | C4···C3ii | 3.593 (12) |
Cl1···O2 | 3.300 (9) | C4···C3iii | 3.550 (12) |
Cl1···O3 | 2.880 (8) | C4···C4iii | 3.451 (12) |
Cl2···O1iv | 2.992 (8) | C5···Br1ii | 3.741 (9) |
Cl2···O2 | 3.266 (9) | C5···Br1iii | 3.620 (9) |
Cl2···O3 | 3.377 (9) | C5···O2ix | 3.275 (11) |
Cl2···N1 | 3.107 (8) | C5···C3iii | 3.519 (11) |
Cl2···C6 | 3.505 (8) | C6···Cl2 | 3.505 (8) |
Cl2···H2v | 3.0800 | C5···H7C | 2.8100 |
O1···Cl1 | 3.125 (8) | C5···H7A | 2.8900 |
O1···Cl2vi | 2.992 (8) | C7···H5 | 2.5700 |
O1···C1 | 3.184 (11) | H2···O3 | 2.4600 |
O2···Cl1 | 3.300 (9) | H2···Cl2x | 3.0800 |
O2···Cl2 | 3.266 (9) | H4···O2ix | 2.6000 |
O2···C4vii | 3.219 (12) | H5···C7 | 2.5700 |
O2···C5vii | 3.275 (11) | H5···H7A | 2.3600 |
O3···Cl2 | 3.377 (9) | H5···H7C | 2.4200 |
O3···Cl1 | 2.880 (8) | H5···O2ix | 2.7200 |
O3···Br1viii | 2.987 (7) | H7A···C5 | 2.8900 |
O2···H7B | 2.3400 | H7A···H5 | 2.3600 |
O2···H5vii | 2.7200 | H7B···O2 | 2.3400 |
O2···H4vii | 2.6000 | H7C···C5 | 2.8100 |
O3···H2 | 2.4600 | H7C···H5 | 2.4200 |
N1···Cl2 | 3.107 (8) | H7C···Br1ii | 3.0600 |
C1···O1 | 3.184 (11) | ||
O1—S1—O2 | 121.1 (5) | Cl1—C8—Cl2 | 111.1 (5) |
O1—S1—N1 | 113.6 (4) | Cl1—C8—S1 | 109.4 (5) |
O1—S1—C8 | 102.1 (5) | Cl1—C8—C9 | 111.4 (6) |
O2—S1—N1 | 108.0 (4) | Cl2—C8—S1 | 111.0 (5) |
O2—S1—C8 | 110.3 (5) | Cl2—C8—C9 | 105.6 (6) |
N1—S1—C8 | 99.4 (4) | S1—C8—C9 | 108.3 (6) |
S1—N1—C6 | 118.0 (5) | O3—C9—C1 | 123.7 (8) |
S1—N1—C7 | 120.1 (6) | O3—C9—C8 | 120.1 (8) |
C6—N1—C7 | 121.4 (7) | C1—C9—C8 | 116.2 (7) |
C2—C1—C6 | 120.0 (7) | C1—C2—H2 | 120.00 |
C2—C1—C9 | 115.4 (7) | C3—C2—H2 | 120.00 |
C6—C1—C9 | 124.6 (7) | C3—C4—H4 | 120.00 |
C1—C2—C3 | 119.7 (8) | C5—C4—H4 | 120.00 |
Br1—C3—C2 | 119.8 (6) | C4—C5—H5 | 120.00 |
Br1—C3—C4 | 119.8 (6) | C6—C5—H5 | 120.00 |
C2—C3—C4 | 120.4 (8) | N1—C7—H7A | 109.00 |
C3—C4—C5 | 120.6 (7) | N1—C7—H7B | 109.00 |
C4—C5—C6 | 120.4 (7) | N1—C7—H7C | 109.00 |
N1—C6—C1 | 121.1 (7) | H7A—C7—H7B | 109.00 |
N1—C6—C5 | 120.0 (7) | H7A—C7—H7C | 109.00 |
C1—C6—C5 | 118.9 (7) | H7B—C7—H7C | 109.00 |
O1—S1—N1—C6 | −52.8 (7) | C2—C1—C6—N1 | 178.0 (7) |
O1—S1—N1—C7 | 118.5 (8) | C2—C1—C6—C5 | −1.9 (11) |
O2—S1—N1—C6 | 169.9 (6) | C9—C1—C6—N1 | −3.0 (12) |
O2—S1—N1—C7 | −18.7 (9) | C9—C1—C6—C5 | 177.1 (8) |
C8—S1—N1—C6 | 54.9 (7) | C2—C1—C9—O3 | −5.9 (13) |
C8—S1—N1—C7 | −133.8 (7) | C2—C1—C9—C8 | 172.1 (7) |
O1—S1—C8—Cl1 | −64.1 (6) | C6—C1—C9—O3 | 175.1 (9) |
O1—S1—C8—Cl2 | 173.0 (5) | C6—C1—C9—C8 | −6.9 (12) |
O1—S1—C8—C9 | 57.5 (7) | C1—C2—C3—Br1 | −178.4 (6) |
O2—S1—C8—Cl1 | 65.9 (6) | C1—C2—C3—C4 | 0.2 (12) |
O2—S1—C8—Cl2 | −57.0 (6) | Br1—C3—C4—C5 | 177.3 (6) |
O2—S1—C8—C9 | −172.5 (6) | C2—C3—C4—C5 | −1.2 (12) |
N1—S1—C8—Cl1 | 179.2 (5) | C3—C4—C5—C6 | 0.7 (13) |
N1—S1—C8—Cl2 | 56.3 (5) | C4—C5—C6—N1 | −179.1 (7) |
N1—S1—C8—C9 | −59.3 (6) | C4—C5—C6—C1 | 0.8 (12) |
S1—N1—C6—C1 | −27.0 (10) | Cl1—C8—C9—O3 | −21.8 (12) |
S1—N1—C6—C5 | 152.9 (6) | Cl1—C8—C9—C1 | 160.1 (6) |
C7—N1—C6—C1 | 161.8 (8) | Cl2—C8—C9—O3 | 98.9 (9) |
C7—N1—C6—C5 | −18.3 (11) | Cl2—C8—C9—C1 | −79.2 (8) |
C6—C1—C2—C3 | 1.4 (12) | S1—C8—C9—O3 | −142.1 (8) |
C9—C1—C2—C3 | −177.7 (7) | S1—C8—C9—C1 | 39.8 (9) |
Symmetry codes: (i) −x+3/2, y+1/2, −z+3/2; (ii) −x+1, −y+1, −z+1; (iii) −x+2, −y+1, −z+1; (iv) x−1, y, z; (v) x−1/2, −y+1/2, z−1/2; (vi) x+1, y, z; (vii) −x+3/2, y−1/2, −z+1/2; (viii) −x+3/2, y−1/2, −z+3/2; (ix) −x+3/2, y+1/2, −z+1/2; (x) x+1/2, −y+1/2, z+1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
C7—H7B···O2 | 0.9600 | 2.3400 | 2.834 (14) | 112.00 |
Experimental details
Crystal data | |
Chemical formula | C9H6BrCl2NO3S |
Mr | 359.02 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 296 |
a, b, c (Å) | 7.0285 (9), 14.865 (2), 11.9739 (18) |
β (°) | 92.418 (5) |
V (Å3) | 1249.9 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 3.88 |
Crystal size (mm) | 0.26 × 0.14 × 0.12 |
Data collection | |
Diffractometer | Bruker Kappa-APEXII CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2005) |
Tmin, Tmax | 0.529, 0.626 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 11409, 2317, 1595 |
Rint | 0.048 |
(sin θ/λ)max (Å−1) | 0.606 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.082, 0.249, 1.09 |
No. of reflections | 2317 |
No. of parameters | 155 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 2.07, −0.46 |
Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
C7—H7B···O2 | 0.9600 | 2.3400 | 2.834 (14) | 112.00 |
Acknowledgements
MS gratefully acknowledges the Higher Education Commission, Islamabad, Pakistan, for providing a scholarship under the Indigenous PhD Program (PIN 042-120567-PS2-276).
References
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We have reported crystal structures of the synthesized derivatives of the benzothiazine molecules which have halogen substitutions (Shafiq et al., 2008; Shafiq, Tahir, Khan Ahmad et al., 2009; Shafiq, Tahir, Khan, Arshad & Asghar, 2009; Shafiq, Tahir, Khan, Arshad & Safdar, 2009). In continuation to the halogenation of our synthesized benzothiazines, we herein report the title compound (I), (Fig. 1).
(I) is closely related to the crystal structure of 3,3-Dichloro-1-ethyl-1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide, (II), (Shafiq, Tahir, Khan, Ahmad et al., 2009). (I) differs from (II) due to methyl moiety at N-atom instead of ethyl and the attachement of Br-atom to the benzene ring. The title compound is from one of those compounds which have high order of steric hinderences. This is why, the R-values remain higher.
In (I), the heterocyclic ring A (C1/C6/N1/S1/C8/C9) is in the twisted form, with the maximum puckering amplitude QT = 0.604 (7) Å (Cremer & Pople, 1975). The molecules are stabilized due to weak intramolecular H-bonding (Table 1) and π—π interactions between the centroids (CgA) of ring A. The distance between CgA···CgAi [symmetry code: i = 1 - x, 1 - y, 1 - z] is 4.191 (5) Å, whereas it is 4.110 (5) Å for CgA···CgAii [symmetry code: i = 1 - x, 1 - y, 1 - z]. The stacking of molecules is shown in Fig 2. The Br-atom is at a distance of -0.07 (1) Å from the mean square plane of benzene ring B (C1—C6) and the S-atom is at a distance of -0.879 (9) Å from the mean square plane of group C (C1/C6/N1/C8/C9).