Methyl 5-bromo-2-[meth­yl(methyl­sulfon­yl)amino]benzoate

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

doi:10.1107/S1600536809011829

organic compounds

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ISSN: 2056-9890

Volume 65| Part 5| May 2009| Page o955

doi:10.1107/S1600536809011829

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Methyl 5-bromo-2-[methyl(methylsulfonyl)amino]benzoate

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

^aDepartment of Chemistry, Government College University, Lahore, Pakistan, and ^bDepartment of Physics, University of Sargodha, Sargodha, Pakistan
^*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 28 March 2009; accepted 30 March 2009; online 2 April 2009)

The title compound, C₁₀H₁₂BrNO₄S, is an intermediate in the synthesis of benzothiazine. The planar methyl ester group (maximum deviation is 0.0065 Å) is oriented at a dihedral angle of 39.09 (13)° with respect to the aromatic ring. In the crystal structure, weak intermolecular C—H⋯O interactions link the molecules into centrosymmetric dimers, through R₂²(10) ring motifs.

Related literature

For related structures, see: Arshad et al. (2008 ); Shafiq et al. (2009 ); Tahir et al. (2008 ). For bond-length data, see: Allen et al. (1987 ). For ring-motifs, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₁₀H₁₂BrNO₄S
M_r = 322.18
Monoclinic, P 2₁ /c
a = 6.0798 (1) Å
b = 10.7853 (3) Å
c = 19.5206 (4) Å
β = 90.306 (1)°
V = 1280.00 (5) Å³
Z = 4
Mo Kα radiation
μ = 3.38 mm⁻¹
T = 296 K
0.28 × 0.10 × 0.08 mm

Data collection

Bruker Kappa APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.675, T_max = 0.766
13682 measured reflections
3170 independent reflections
2215 reflections with I > 2σ(I)
R_int = 0.032

Refinement

R[F² > 2σ(F²)] = 0.034
wR(F²) = 0.084
S = 1.04
3170 reflections
157 parameters
H-atom parameters constrained
Δρ_max = 0.50 e Å⁻³
Δρ_min = −0.43 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C6—H6⋯O2ⁱ	0.93	2.43	3.319 (3)	159
Symmetry code: (i) -x+1, -y+1, -z.

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 (Spek, 2009).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809011829/hk2657sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809011829/hk2657Isup2.hkl

checkCIF report

Comment top

We have reported the crystal structures of some benzothiazine derivatives (Shafiq et al., 2009; Tahir et al., 2008; Arshad et al., 2008). The title compound is an intermediate for the synthesis of benzothiazine and we report herein its crystal structure.

In the molecule of the title compound (Fig. 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. Ring A (C1-C6) is of course planar. The methyl ester moiety B (O2/C7/O1/C8) is also planar, and they are oriented at a dihedral angle of 39.09 (13)°.

In the crystal structure, weak intermolecular C-H···O interactions link the molecules into centrosymmetric dimers through R₂²(10) ring motifs (Fig. 2) (Bernstein et al., 1995).

Related literature top

For related structures, see: Arshad et al. (2008); Shafiq et al. (2009); Tahir et al. (2008). For bond-length data, see: Allen et al. (1987). For ring-motifs, see: Bernstein et al. (1995).

Experimental top

For the preparation of the title compound, methyl-2-amino-5-bromobenzoate (1 g, 4 mmol) was added into dichloromethane (10 ml) in a round bottom flask. Then, a solution of methanesulfonyl chloride (0.55 g, 48 mmol) in dichloromethane (10 ml) was added to the mixture in 10-15 min. The mixture was stirred at 333-343 K for 2-3 d. After the completion of reaction, the solvent was evaporated under reduced pressure to get methyl-5-bromo-2-[(methylsulfonyl)amino]benzoate. Methyl-5-bromo-2-[(methylsulfonyl)amino] benzoate (1 g, 33 mmol) was added into dimethylformamide (5 ml), and then to a suspension of NaH (0.15 g, 66 mmol) in dimethylformamide (10 ml). The mixture was stirred at room temperature for 14-16 h, then the title compound was obtained.

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 molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. A partial packing diagram of the title compound. Hydrogen bonds are shown as dashed lines.

Methyl 5-bromo-2-[methyl(methylsulfonyl)amino]benzoate top

Crystal data top

C₁₀H₁₂BrNO₄S	F(000) = 648
M_r = 322.18	D_x = 1.672 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3094 reflections
a = 6.0798 (1) Å	θ = 2.1–28.3°
b = 10.7853 (3) Å	µ = 3.38 mm⁻¹
c = 19.5206 (4) Å	T = 296 K
β = 90.306 (1)°	Needle, yellow
V = 1280.00 (5) Å³	0.28 × 0.10 × 0.08 mm
Z = 4

Data collection top

Bruker Kappa APEXII CCD area-detector diffractometer	3170 independent reflections
Radiation source: fine-focus sealed tube	2215 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.032
Detector resolution: 7.40 pixels mm^-1	θ_max = 28.3°, θ_min = 2.1°
ω scans	h = −7→8
Absorption correction: multi-scan (SADABS; Bruker, 2005)	k = −11→14
T_min = 0.675, T_max = 0.766	l = −26→18
13682 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)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.084	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0383P)² + 0.314P] where P = (F_o² + 2F_c²)/3
3170 reflections	(Δ/σ)_max = 0.001
157 parameters	Δρ_max = 0.50 e Å⁻³
0 restraints	Δρ_min = −0.43 e Å⁻³

Crystal data top

C₁₀H₁₂BrNO₄S	V = 1280.00 (5) Å³
M_r = 322.18	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 6.0798 (1) Å	µ = 3.38 mm⁻¹
b = 10.7853 (3) Å	T = 296 K
c = 19.5206 (4) Å	0.28 × 0.10 × 0.08 mm
β = 90.306 (1)°

Data collection top

Bruker Kappa APEXII CCD area-detector diffractometer	3170 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	2215 reflections with I > 2σ(I)
T_min = 0.675, T_max = 0.766	R_int = 0.032
13682 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.034	0 restraints
wR(F²) = 0.084	H-atom parameters constrained
S = 1.04	Δρ_max = 0.50 e Å⁻³
3170 reflections	Δρ_min = −0.43 e Å⁻³
157 parameters

Special details top

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 e.s.d.'s 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Br1	0.87436 (5)	0.17725 (3)	−0.05236 (1)	0.0593 (1)
S1	0.31436 (11)	0.27222 (6)	0.25490 (3)	0.0430 (2)
O1	0.0398 (3)	0.36804 (16)	0.10645 (9)	0.0480 (6)
O2	0.3103 (3)	0.49394 (17)	0.07246 (10)	0.0615 (7)
O3	0.1288 (3)	0.2765 (2)	0.29944 (10)	0.0705 (8)
O4	0.3995 (4)	0.38536 (16)	0.22837 (9)	0.0626 (8)
N1	0.2453 (3)	0.18507 (17)	0.18980 (10)	0.0405 (7)
C1	0.3871 (4)	0.2795 (2)	0.08386 (11)	0.0351 (7)
C2	0.3870 (4)	0.1830 (2)	0.13144 (11)	0.0361 (7)
C3	0.5263 (4)	0.0825 (2)	0.12135 (13)	0.0485 (9)
C4	0.6658 (4)	0.0783 (3)	0.06623 (13)	0.0514 (9)
C5	0.6714 (4)	0.1765 (2)	0.02093 (12)	0.0400 (8)
C6	0.5328 (4)	0.2764 (2)	0.02934 (12)	0.0392 (8)
C7	0.2441 (4)	0.3927 (2)	0.08770 (11)	0.0397 (8)
C8	−0.1053 (5)	0.4740 (3)	0.11019 (16)	0.0633 (11)
C9	0.1119 (5)	0.0733 (3)	0.20332 (15)	0.0638 (11)
C10	0.5280 (6)	0.1954 (3)	0.29790 (17)	0.0701 (12)
H3	0.52509	0.01710	0.15239	0.0581*
H4	0.75581	0.00965	0.05948	0.0616*
H6	0.53683	0.34191	−0.00159	0.0470*
H8A	−0.03451	0.53922	0.13547	0.0948*
H8B	−0.23879	0.45063	0.13284	0.0948*
H8C	−0.13892	0.50247	0.06473	0.0948*
H9A	0.05001	0.04344	0.16109	0.0955*
H9B	−0.00446	0.09371	0.23442	0.0955*
H9C	0.20333	0.01021	0.22325	0.0955*
H10A	0.65597	0.19335	0.26931	0.1052*
H10B	0.48324	0.11214	0.30829	0.1052*
H10C	0.56198	0.23847	0.33966	0.1052*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0607 (2)	0.0684 (2)	0.0489 (2)	0.0212 (1)	0.0172 (1)	−0.0024 (1)
S1	0.0595 (4)	0.0354 (3)	0.0342 (3)	0.0018 (3)	0.0066 (3)	−0.0019 (3)
O1	0.0388 (10)	0.0460 (10)	0.0593 (11)	0.0085 (8)	0.0031 (8)	−0.0053 (9)
O2	0.0691 (14)	0.0389 (10)	0.0769 (13)	0.0149 (9)	0.0276 (11)	0.0158 (10)
O3	0.0828 (16)	0.0770 (14)	0.0520 (12)	0.0100 (12)	0.0257 (11)	−0.0111 (11)
O4	0.1016 (17)	0.0352 (10)	0.0510 (11)	−0.0133 (10)	0.0043 (11)	−0.0036 (9)
N1	0.0501 (13)	0.0370 (11)	0.0343 (10)	−0.0033 (9)	0.0034 (9)	0.0001 (9)
C1	0.0374 (13)	0.0351 (12)	0.0327 (11)	0.0055 (10)	−0.0008 (10)	−0.0006 (10)
C2	0.0418 (14)	0.0350 (13)	0.0315 (11)	0.0009 (10)	0.0003 (10)	−0.0019 (10)
C3	0.0645 (18)	0.0357 (14)	0.0452 (14)	0.0104 (12)	0.0036 (12)	0.0063 (11)
C4	0.0591 (18)	0.0456 (15)	0.0495 (15)	0.0225 (13)	0.0059 (13)	−0.0023 (12)
C5	0.0431 (14)	0.0423 (14)	0.0346 (12)	0.0070 (11)	0.0020 (10)	−0.0058 (10)
C6	0.0441 (14)	0.0387 (13)	0.0347 (12)	0.0059 (12)	0.0025 (10)	0.0032 (10)
C7	0.0476 (16)	0.0397 (14)	0.0318 (11)	0.0093 (12)	0.0045 (10)	0.0024 (10)
C8	0.0525 (19)	0.068 (2)	0.0695 (19)	0.0233 (15)	0.0025 (15)	−0.0155 (16)
C9	0.064 (2)	0.0674 (19)	0.0600 (17)	−0.0252 (16)	0.0120 (14)	−0.0095 (15)
C10	0.081 (2)	0.063 (2)	0.066 (2)	0.0056 (17)	−0.0241 (18)	−0.0031 (15)

Geometric parameters (Å, º) top

Br1—C5	1.894 (2)	C4—C5	1.380 (4)
S1—O3	1.429 (2)	C5—C6	1.378 (3)
S1—O4	1.424 (2)	C3—H3	0.9300
S1—N1	1.634 (2)	C4—H4	0.9300
S1—C10	1.751 (4)	C6—H6	0.9300
O1—C7	1.324 (3)	C8—H8A	0.9600
O1—C8	1.446 (4)	C8—H8B	0.9600
O2—C7	1.202 (3)	C8—H8C	0.9600
N1—C2	1.432 (3)	C9—H9A	0.9600
N1—C9	1.478 (4)	C9—H9B	0.9600
C1—C2	1.395 (3)	C9—H9C	0.9600
C1—C6	1.389 (3)	C10—H10A	0.9600
C1—C7	1.501 (3)	C10—H10B	0.9600
C2—C3	1.390 (3)	C10—H10C	0.9600
C3—C4	1.374 (4)

Br1···O3ⁱ	3.3255 (19)	C1···H8B^x	3.0800
Br1···H4ⁱⁱ	3.0200	C3···H9C	2.9100
Br1···H9Aⁱⁱⁱ	3.2200	C3···H9A	3.0300
Br1···H10C^iv	2.9700	C4···H9A^x	3.0000
S1···O1	3.4929 (19)	C6···H8B^x	3.0800
S1···C7	3.537 (2)	C9···H3	2.7700
O1···S1	3.4929 (19)	C9···H10B	3.0700
O1···O4	3.229 (3)	H3···C9	2.7700
O1···N1	2.843 (3)	H3···H9C	2.4000
O2···C6^v	3.319 (3)	H3···O4^xii	2.7600
O3···Br1^vi	3.3255 (19)	H4···Br1ⁱⁱ	3.0200
O4···O1	3.229 (3)	H6···O2	2.5900
O4···C7	2.900 (3)	H6···O2^v	2.4300
O4···C10^vii	3.412 (4)	H8A···O2	2.4800
O4···C1	3.044 (3)	H8A···O3^xiii	2.9200
O2···H6	2.5900	H8B···C1^xi	3.0800
O2···H8C	2.7400	H8B···C6^xi	3.0800
O2···H8A	2.4800	H8B···H10B^xiii	2.5700
O2···H8C^viii	2.8700	H8C···O2	2.7400
O2···H6^v	2.4300	H8C···O2^viii	2.8700
O3···H8A^ix	2.9200	H9A···C3	3.0300
O3···H9B	2.4800	H9A···C4^xi	3.0000
O4···H3^vii	2.7600	H9A···Br1ⁱⁱⁱ	3.2200
O4···H9C^vii	2.9200	H9B···O3	2.4800
O4···H10B^vii	2.6500	H9B···H10A^xi	2.4300
N1···O1	2.843 (3)	H9C···C3	2.9100
C1···O4	3.044 (3)	H9C···H3	2.4000
C6···O2^v	3.319 (3)	H9C···O4^xii	2.9200
C6···C8^x	3.441 (4)	H10A···H9B^x	2.4300
C7···S1	3.537 (2)	H10B···C9	3.0700
C7···O4	2.900 (3)	H10B···O4^xii	2.6500
C8···C6^xi	3.441 (4)	H10B···H8B^ix	2.5700
C10···O4^xii	3.412 (4)	H10C···Br1^xiv	2.9700

O3—S1—O4	118.90 (13)	C2—C3—H3	119.00
O3—S1—N1	106.95 (11)	C4—C3—H3	119.00
O3—S1—C10	108.04 (14)	C3—C4—H4	120.00
O4—S1—N1	107.61 (10)	C5—C4—H4	120.00
O4—S1—C10	108.04 (15)	C1—C6—H6	120.00
N1—S1—C10	106.71 (13)	C5—C6—H6	120.00
C7—O1—C8	115.4 (2)	O1—C8—H8A	109.00
S1—N1—C2	118.33 (15)	O1—C8—H8B	109.00
S1—N1—C9	118.00 (17)	O1—C8—H8C	109.00
C2—N1—C9	117.55 (19)	H8A—C8—H8B	109.00
C2—C1—C6	119.7 (2)	H8A—C8—H8C	109.00
C2—C1—C7	124.8 (2)	H8B—C8—H8C	109.00
C6—C1—C7	115.46 (19)	N1—C9—H9A	109.00
N1—C2—C1	121.4 (2)	N1—C9—H9B	109.00
N1—C2—C3	119.6 (2)	N1—C9—H9C	109.00
C1—C2—C3	119.0 (2)	H9A—C9—H9B	109.00
C2—C3—C4	121.0 (2)	H9A—C9—H9C	109.00
C3—C4—C5	119.6 (3)	H9B—C9—H9C	109.00
Br1—C5—C4	120.37 (18)	S1—C10—H10A	109.00
Br1—C5—C6	119.20 (17)	S1—C10—H10B	109.00
C4—C5—C6	120.4 (2)	S1—C10—H10C	110.00
C1—C6—C5	120.2 (2)	H10A—C10—H10B	109.00
O1—C7—O2	124.5 (2)	H10A—C10—H10C	109.00
O1—C7—C1	113.27 (19)	H10B—C10—H10C	109.00
O2—C7—C1	122.1 (2)

O3—S1—N1—C2	169.01 (17)	C7—C1—C2—C3	179.3 (2)
O3—S1—N1—C9	−39.1 (2)	C2—C1—C6—C5	2.2 (3)
O4—S1—N1—C2	40.2 (2)	C7—C1—C6—C5	−179.9 (2)
O4—S1—N1—C9	−167.94 (19)	C2—C1—C7—O1	−41.7 (3)
C10—S1—N1—C2	−75.6 (2)	C2—C1—C7—O2	141.0 (2)
C10—S1—N1—C9	76.3 (2)	C6—C1—C7—O1	140.6 (2)
C8—O1—C7—O2	−2.1 (3)	C6—C1—C7—O2	−36.8 (3)
C8—O1—C7—C1	−179.4 (2)	N1—C2—C3—C4	−179.4 (2)
S1—N1—C2—C1	−77.8 (3)	C1—C2—C3—C4	1.2 (4)
S1—N1—C2—C3	102.8 (2)	C2—C3—C4—C5	1.4 (4)
C9—N1—C2—C1	130.3 (2)	C3—C4—C5—Br1	176.30 (19)
C9—N1—C2—C3	−49.2 (3)	C3—C4—C5—C6	−2.3 (4)
C6—C1—C2—N1	177.6 (2)	Br1—C5—C6—C1	−178.13 (18)
C6—C1—C2—C3	−3.0 (3)	C4—C5—C6—C1	0.5 (4)
C7—C1—C2—N1	−0.2 (4)

Symmetry codes: (i) x+1, −y+1/2, z−1/2; (ii) −x+2, −y, −z; (iii) −x+1, −y, −z; (iv) x, −y+1/2, z−1/2; (v) −x+1, −y+1, −z; (vi) x−1, −y+1/2, z+1/2; (vii) −x+1, y+1/2, −z+1/2; (viii) −x, −y+1, −z; (ix) −x, y−1/2, −z+1/2; (x) x+1, y, z; (xi) x−1, y, z; (xii) −x+1, y−1/2, −z+1/2; (xiii) −x, y+1/2, −z+1/2; (xiv) x, −y+1/2, z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···O2^v	0.93	2.43	3.319 (3)	159

Symmetry code: (v) −x+1, −y+1, −z.

Experimental details

Crystal data
Chemical formula	C₁₀H₁₂BrNO₄S
M_r	322.18
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	6.0798 (1), 10.7853 (3), 19.5206 (4)
β (°)	90.306 (1)
V (Å³)	1280.00 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	3.38
Crystal size (mm)	0.28 × 0.10 × 0.08

Data collection
Diffractometer	Bruker Kappa APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.675, 0.766
No. of measured, independent and observed [I > 2σ(I)] reflections	13682, 3170, 2215
R_int	0.032
(sin θ/λ)_max (Å⁻¹)	0.666

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.034, 0.084, 1.04
No. of reflections	3170
No. of parameters	157
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.50, −0.43

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
C6—H6···O2ⁱ	0.93	2.43	3.319 (3)	159

Symmetry code: (i) −x+1, −y+1, −z.

Acknowledgements

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

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