6-Bromo-1-methyl-1H-2,1-benzothia­zin-4(3H)-one 2,2-dioxide

Shafiq, M.; Tahir, M.N.; Khan, I.U.; Arshad, M.N.; Asghar, M.N.

doi:10.1107/S1600536809015980

organic compounds

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ISSN: 2056-9890

Volume 65| Part 5| May 2009| Page o1182

doi:10.1107/S1600536809015980

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6-Bromo-1-methyl-1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide

Muhammad Shafiq,^a M. Nawaz Tahir,^b ^* Islam Ullah Khan,^a Muhammad Nadeem Arshad ^a and Muhammad Nadeem Asghar ^a

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

(Received 6 March 2009; accepted 28 April 2009; online 30 April 2009)

In the crystal structure of the title compound, C₉H₈BrNO₃S, the thiazine ring is in the twisted form. In the crystal, pairs of intermolecular C—H⋯O hydrogen bonds form inversion dimers with an R₂²(8) ring motif. Weak intermolecular C—H⋯Br and C—H⋯π interactions are also present.

Related literature

For the structures of benzothiazine derivatives, see: Arshad et al. (2008 ); Shafiq et al. (2008a ,b ); Tahir et al. (2008 ). For the related structure, 6-bromo-1-methyl-1H-benzo[c][1,2]thiazin-4(3H)-one 2,2-dioxide, see: Shafiq et al. (2009 ). For hydrogen-bond motifs, see: Bernstein et al. (1995 ). For puckering parameters, see: Cremer & Pople (1975 ). For the synthesis, see: Lombardino (1972 ).

Experimental

Crystal data

C₉H₈BrNO₃S
M_r = 290.13
Monoclinic, P 2₁ /n
a = 5.4577 (3) Å
b = 12.6400 (8) Å
c = 15.1258 (10) Å
β = 96.204 (2)°
V = 1037.35 (11) Å³
Z = 4
Mo Kα radiation
μ = 4.15 mm⁻¹
T = 296 K
0.20 × 0.17 × 0.15 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.439, T_max = 0.540
11077 measured reflections
2234 independent reflections
1709 reflections with I > 2σ(I)
R_int = 0.032

Refinement

R[F² > 2σ(F²)] = 0.030
wR(F²) = 0.072
S = 1.04
2234 reflections
137 parameters
H-atom parameters constrained
Δρ_max = 0.41 e Å⁻³
Δρ_min = −0.35 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C3—H3⋯O3ⁱ	0.93	2.54	3.308 (4)	140
C8—H8A⋯O2ⁱⁱ	0.97	2.54	3.470 (3)	162
C9—H9B⋯O3	0.96	2.41	2.824 (3)	106
C5—H5⋯Br1ⁱⁱⁱ	0.93	2.94	3.871 (3)	175
C9—H9A⋯Br1^iv	0.96	3.01	3.871 (2)	150
C9—H9C⋯Cg1^v	0.96	2.83	3.449 (3)	123
Symmetry codes: (i) $[-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) -x+1, -y, -z+1; (iii) -x, -y+1, -z+1; (iv) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (v) x+1, y, z. Cg1 is the centroid of the C1–C6 ring.

Data collection: APEX2 (Bruker, 2007 ); cell refinement: 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

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809015980/fb2142sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809015980/fb2142Isup2.hkl

checkCIF report

Comment top

We have reported crystal structures of the synthesized derivatives of the benzothiazine molecule (Shafiq et al., 2008a; Shafiq et al., 2008b; Tahir et al., 2008; Arshad et al., 2008). Here we report the title compound (I), (Fig. 1), that belongs to this series of the structures.

(I) is closely related to the crystal structure of 6-bromo-1-methyl-1H-benzo[c][1,2]thiazin-4(3H)-one 2,2-dioxide, (II), (Shafiq et al., 2009). (I) and (II) differ by the presence of the methyl and ethyl groups at the N-atom, respectively. The bromo-substituted benzene ring A (C1—C6) is planar with Br deviated by 0.064 (4) Å from the mean plane. The thiazine ring B (S1/N1/C1/C6—C8) is in the twisted form, with the maximum puckering amplitude Q_T = 0.577 (2) Å (Cremer & Pople, 1975). The title molecules form dimers interconnected by a pair of the intermolecular H-bonds C8–H8A···O2ⁱ [symmetry code: i = -x + 1, -y, -z + 1] with the R₂²(8) ring motif (Bernstein et al., 1995), (Tab. 1, Fig. 2). The dimers are linked to each other forming helices through the other intermolecular H-bonding C3–H3···O3ⁱⁱ [symmetry code: ii = -x + 3/2, y + 1/2, -z + 1/2]. The molecules are also stabilized due to C—H···π-electron interaction with the benzene group and intermolecular C—H···Br interactions (Tab. 1).

Related literature top

For the structures of benzothiazine derivatives, see: Arshad et al. (2008); Shafiq et al. (2008a,b); Tahir et al. (2008). For the related structure, 6-bromo-1-methyl-1H-benzo[c][1,2]thiazin-4(3H)-one 2,2-dioxide, see: Shafiq et al. (2009). For hydrogen-bond motifs, see: Bernstein et al. (1995). For puckering parameters, see: Cremer & Pople (1975). For the synthesis, see: Lombardino (1972). Cg1 is the centroid of the C1–C6 ring.

Experimental top

The title compound was prepared in a three step scheme following the reported procedure (Lombardino, 1972). In the first step, methyl-2-amino-5-bromobenzoate (92 mg, 4 mmol) was put in dichloromethane (10 ml) and this mixture was introduced into a round bottom flask. A solution of methanesulfonyl chloride (550 mg, 4.8 mmol) in dichloromethane (10 ml) was slowly added (10-15 minutes) to this mixture. The mixture was stirred at 60–70 °C for 2–3 days keeping pH of the mixture alkaline by triethylamine. After the completion of the reaction, the solvent was evaporated under reduced pressure to get methyl-5-bromo-2-[(methylsulfonyl)amino] benzoate.

In the second step, methyl-5-bromo-2-[(methylsulfonyl)amino] benzoate (1.02 g, 3.3 mmol) was introduced into 5 ml of N,N-dimethylformamide (DMF). The mixture was added to a suspension of NaH (158.38 mg, 6.6 mmol) in DMF (10 ml). The mixture was stirred at room temperature for 14–16 h. After that, methyl-5-bromo-2-[methyl(methylsulfonyl)amino]benzoate was obtained.

In the third step methyl-5-bromo-2-[methyl(methylsulfonyl)amino]benzoate was cyclized. Therefore methyl-5-bromo-2-[methyl(methylsulfonyl)amino]benzoate (418.83 mg, 1.3 mmol) was introduced in DMF (5 ml) and added to the suspension of NaH (59.99 mg, 2.5 mmol) in DMF (10 ml). The mixture was stirred at room temperature for 3–4 h. Then the reaction mixture was poured into ice and clear solution was obtained. The pH of this solution was adjusted between 5–6. The precipitated crude product was recrystallized from ethanol. Yellow needle-shaped crystals of the title compound of suitable size for structure analysis were grown in this way.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: 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).

Figures top

	Fig. 1. The title compound, with the atom-numbering scheme. The displacement ellipsoids are drawn at the 50% probability level. The H-atoms are shown by small circles of arbitrary radius. The dotted lines show the intramolecular H-bonds.
	Fig. 2. A section of the title structure showing the dimers bind by the hydrogen bonds.

6-Bromo-1-methyl-1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide top

Crystal data top

C₉H₈BrNO₃S	F(000) = 576
M_r = 290.13	D_x = 1.858 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2234 reflections
a = 5.4577 (3) Å	θ = 2.1–27.0°
b = 12.6400 (8) Å	µ = 4.15 mm⁻¹
c = 15.1258 (10) Å	T = 296 K
β = 96.204 (2)°	Prism, yellow
V = 1037.35 (11) Å³	0.20 × 0.17 × 0.15 mm
Z = 4

Data collection top

Bruker Kappa APEXII CCD diffractometer	2234 independent reflections
Radiation source: fine-focus sealed tube	1709 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.032
Detector resolution: 7.40 pixels mm^-1	θ_max = 27.0°, θ_min = 2.1°
ω scans	h = −6→6
Absorption correction: multi-scan (SADABS; Bruker, 2005)	k = −16→16
T_min = 0.439, T_max = 0.540	l = −18→19
11077 measured reflections

Refinement top

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)] = 0.030	Hydrogen site location: difference Fourier map
wR(F²) = 0.072	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0309P)² + 0.4349P] where P = (F_o² + 2F_c²)/3
2234 reflections	(Δ/σ)_max = 0.001
137 parameters	Δρ_max = 0.41 e Å⁻³
0 restraints	Δρ_min = −0.35 e Å⁻³
31 constraints

Crystal data top

C₉H₈BrNO₃S	V = 1037.35 (11) Å³
M_r = 290.13	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 5.4577 (3) Å	µ = 4.15 mm⁻¹
b = 12.6400 (8) Å	T = 296 K
c = 15.1258 (10) Å	0.20 × 0.17 × 0.15 mm
β = 96.204 (2)°

Data collection top

Bruker Kappa APEXII CCD diffractometer	2234 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	1709 reflections with I > 2σ(I)
T_min = 0.439, T_max = 0.540	R_int = 0.032
11077 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.030	0 restraints
wR(F²) = 0.072	H-atom parameters constrained
S = 1.04	Δρ_max = 0.41 e Å⁻³
2234 reflections	Δρ_min = −0.35 e Å⁻³
137 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

	x	y	z	U_iso*/U_eq
Br1	0.06150 (6)	0.57510 (2)	0.36727 (2)	0.05871 (14)
S1	0.74473 (12)	0.10243 (5)	0.40740 (4)	0.03706 (17)
O1	0.3779 (4)	0.23972 (17)	0.56688 (14)	0.0606 (6)
O2	0.5116 (4)	0.05733 (15)	0.37692 (14)	0.0529 (5)
O3	0.9592 (4)	0.03989 (16)	0.40469 (14)	0.0555 (6)
N1	0.7895 (4)	0.21290 (17)	0.35343 (14)	0.0385 (5)
C1	0.6129 (4)	0.29366 (19)	0.35581 (16)	0.0326 (6)
C2	0.5631 (5)	0.3622 (2)	0.28382 (19)	0.0403 (6)
H2	0.6430	0.3525	0.2332	0.048*
C3	0.3980 (5)	0.4437 (2)	0.2866 (2)	0.0430 (7)
H3	0.3650	0.4882	0.2378	0.052*
C4	0.2814 (5)	0.4595 (2)	0.36193 (19)	0.0409 (6)
C5	0.3200 (5)	0.3919 (2)	0.43312 (19)	0.0416 (6)
H5	0.2368	0.4024	0.4829	0.050*
C6	0.4846 (4)	0.3073 (2)	0.43087 (17)	0.0362 (6)
C7	0.5129 (5)	0.2357 (2)	0.50864 (18)	0.0407 (6)
C8	0.7204 (5)	0.1553 (2)	0.51326 (17)	0.0419 (6)
H8A	0.6884	0.0989	0.5540	0.050*
H8B	0.8745	0.1891	0.5355	0.050*
C9	0.9601 (4)	0.2116 (2)	0.28524 (19)	0.0415 (6)
H9A	0.8798	0.1812	0.2316	0.062*
H9B	1.1024	0.1701	0.3057	0.062*
H9C	1.0102	0.2826	0.2737	0.062*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0680 (2)	0.0468 (2)	0.0609 (2)	0.02306 (14)	0.00505 (16)	0.00177 (15)
S1	0.0439 (3)	0.0358 (4)	0.0327 (4)	0.0072 (3)	0.0098 (3)	0.0042 (3)
O1	0.0815 (14)	0.0670 (14)	0.0380 (12)	0.0261 (11)	0.0282 (11)	0.0127 (11)
O2	0.0603 (12)	0.0441 (12)	0.0541 (14)	−0.0125 (9)	0.0050 (10)	0.0006 (10)
O3	0.0652 (12)	0.0557 (13)	0.0489 (13)	0.0284 (10)	0.0214 (10)	0.0133 (10)
N1	0.0420 (11)	0.0415 (13)	0.0350 (13)	0.0070 (9)	0.0179 (10)	0.0092 (10)
C1	0.0345 (12)	0.0319 (14)	0.0317 (15)	−0.0013 (10)	0.0052 (10)	0.0010 (11)
C2	0.0446 (14)	0.0398 (15)	0.0382 (17)	0.0001 (11)	0.0127 (12)	0.0070 (12)
C3	0.0523 (15)	0.0346 (15)	0.0423 (17)	−0.0010 (12)	0.0061 (13)	0.0102 (12)
C4	0.0426 (13)	0.0343 (14)	0.0453 (18)	0.0060 (11)	0.0026 (12)	−0.0001 (13)
C5	0.0483 (15)	0.0431 (15)	0.0347 (16)	0.0084 (12)	0.0104 (12)	−0.0017 (13)
C6	0.0415 (13)	0.0386 (15)	0.0288 (15)	0.0030 (11)	0.0051 (11)	0.0017 (11)
C7	0.0502 (14)	0.0431 (16)	0.0296 (15)	0.0072 (12)	0.0080 (12)	0.0006 (12)
C8	0.0523 (15)	0.0464 (17)	0.0274 (15)	0.0104 (12)	0.0058 (12)	0.0057 (12)
C9	0.0403 (13)	0.0444 (16)	0.0425 (17)	−0.0026 (11)	0.0171 (12)	−0.0018 (13)

Geometric parameters (Å, º) top

Br1—C4	1.898 (3)	C3—C4	1.379 (4)
S1—O3	1.4169 (19)	C3—H3	0.9300
S1—O2	1.424 (2)	C4—C5	1.372 (4)
S1—N1	1.649 (2)	C5—C6	1.400 (3)
S1—C8	1.753 (3)	C5—H5	0.9300
O1—C7	1.209 (3)	C6—C7	1.479 (4)
N1—C1	1.407 (3)	C7—C8	1.518 (3)
N1—C9	1.463 (3)	C8—H8A	0.9700
C1—C2	1.395 (3)	C8—H8B	0.9700
C1—C6	1.407 (3)	C9—H9A	0.9600
C2—C3	1.373 (4)	C9—H9B	0.9600
C2—H2	0.9300	C9—H9C	0.9600

O3—S1—O2	118.63 (13)	C4—C5—C6	120.1 (2)
O3—S1—N1	106.93 (11)	C4—C5—H5	120.0
O2—S1—N1	110.70 (12)	C6—C5—H5	120.0
O3—S1—C8	112.54 (13)	C5—C6—C1	119.3 (2)
O2—S1—C8	107.17 (13)	C5—C6—C7	117.4 (2)
N1—S1—C8	99.15 (12)	C1—C6—C7	123.2 (2)
C1—N1—C9	121.1 (2)	O1—C7—C6	122.3 (2)
C1—N1—S1	117.60 (16)	O1—C7—C8	120.3 (2)
C9—N1—S1	118.62 (17)	C6—C7—C8	117.4 (2)
C2—C1—N1	120.5 (2)	C7—C8—S1	110.06 (18)
C2—C1—C6	118.8 (2)	C7—C8—H8A	109.6
N1—C1—C6	120.8 (2)	S1—C8—H8A	109.6
C3—C2—C1	121.1 (2)	C7—C8—H8B	109.6
C3—C2—H2	119.5	S1—C8—H8B	109.6
C1—C2—H2	119.5	H8A—C8—H8B	108.2
C2—C3—C4	119.8 (3)	N1—C9—H9A	109.5
C2—C3—H3	120.1	N1—C9—H9B	109.5
C4—C3—H3	120.1	H9A—C9—H9B	109.5
C5—C4—C3	120.9 (2)	N1—C9—H9C	109.5
C5—C4—Br1	119.3 (2)	H9A—C9—H9C	109.5
C3—C4—Br1	119.8 (2)	H9B—C9—H9C	109.5

O3—S1—N1—C1	−172.74 (19)	Br1—C4—C5—C6	−179.0 (2)
O2—S1—N1—C1	56.7 (2)	C4—C5—C6—C1	1.2 (4)
C8—S1—N1—C1	−55.7 (2)	C4—C5—C6—C7	−178.3 (2)
O3—S1—N1—C9	25.6 (2)	C2—C1—C6—C5	−3.1 (4)
O2—S1—N1—C9	−105.0 (2)	N1—C1—C6—C5	176.5 (2)
C8—S1—N1—C9	142.7 (2)	C2—C1—C6—C7	176.5 (2)
C9—N1—C1—C2	12.8 (4)	N1—C1—C6—C7	−3.9 (4)
S1—N1—C1—C2	−148.4 (2)	C5—C6—C7—O1	9.9 (4)
C9—N1—C1—C6	−166.8 (2)	C1—C6—C7—O1	−169.7 (3)
S1—N1—C1—C6	32.0 (3)	C5—C6—C7—C8	−170.1 (2)
N1—C1—C2—C3	−177.5 (2)	C1—C6—C7—C8	10.3 (4)
C6—C1—C2—C3	2.0 (4)	O1—C7—C8—S1	139.9 (2)
C1—C2—C3—C4	0.9 (4)	C6—C7—C8—S1	−40.0 (3)
C2—C3—C4—C5	−2.8 (4)	O3—S1—C8—C7	170.50 (19)
C2—C3—C4—Br1	177.9 (2)	O2—S1—C8—C7	−57.3 (2)
C3—C4—C5—C6	1.7 (4)	N1—S1—C8—C7	57.8 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O3ⁱ	0.93	2.54	3.308 (4)	140
C8—H8A···O2ⁱⁱ	0.97	2.54	3.470 (3)	162
C9—H9B···O3	0.96	2.41	2.824 (3)	106
C5—H5···Br1ⁱⁱⁱ	0.93	2.94	3.871 (3)	175
C9—H9A···Br1^iv	0.96	3.01	3.871 (2)	150
C9—H9C···Cg1^v	0.96	2.83	3.449 (3)	123

Symmetry codes: (i) −x+3/2, y+1/2, −z+1/2; (ii) −x+1, −y, −z+1; (iii) −x, −y+1, −z+1; (iv) −x+1/2, y−1/2, −z+1/2; (v) x+1, y, z.

Experimental details

Crystal data
Chemical formula	C₉H₈BrNO₃S
M_r	290.13
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	296
a, b, c (Å)	5.4577 (3), 12.6400 (8), 15.1258 (10)
β (°)	96.204 (2)
V (Å³)	1037.35 (11)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	4.15
Crystal size (mm)	0.20 × 0.17 × 0.15

Data collection
Diffractometer	Bruker Kappa APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.439, 0.540
No. of measured, independent and observed [I > 2σ(I)] reflections	11077, 2234, 1709
R_int	0.032
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.030, 0.072, 1.04
No. of reflections	2234
No. of parameters	137
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.41, −0.35

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).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O3ⁱ	0.93	2.5400	3.308 (4)	140.00
C8—H8A···O2ⁱⁱ	0.97	2.5400	3.470 (3)	162.00
C9—H9B···O3	0.96	2.4100	2.824 (3)	106.00
C5—H5···Br1ⁱⁱⁱ	0.93	2.9440	3.871 (3)	175.09
C9—H9A···Br1^iv	0.96	3.0095	3.871 (2)	150.03
C9—H9C···Cg1^v	0.96	2.8300	3.449 (3)	123.00

Symmetry codes: (i) −x+3/2, y+1/2, −z+1/2; (ii) −x+1, −y, −z+1; (iii) −x, −y+1, −z+1; (iv) −x+1/2, y−1/2, −z+1/2; (v) x+1, y, z.

Acknowledgements

MS gratefully acknowledges the Higher Education Commission, Islamabad, Pakistan, for providing a Scholarship under the Indigenous PhD Program (PIN 042–120567-PS2–276).

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