N-(3-Bromo-5-methyl-2-pyrid­yl)-4-methyl­benzene­sulfonamide

Peng, M.; Luo, Y.; Chen, L.

doi:10.1107/S1600536809054014

organic compounds

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ISSN: 2056-9890

Volume 66| Part 1| January 2010| Page o205

doi:10.1107/S1600536809054014

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N-(3-Bromo-5-methyl-2-pyridyl)-4-methylbenzenesulfonamide

Ming Peng,^a Youfu Luo ^a ^* and Lijuan Chen ^a

^aState Key Laboratory of Biotherapy, Sichuan University, Chengdu 610064, People's Republic of China
^*Correspondence e-mail: luo_youfu@scu.edu.cn

(Received 8 November 2009; accepted 15 December 2009; online 19 December 2009)

In the molecule of the title compound, C₁₃H₁₃BrN₂O₂S, the dihedral angle formed by the pyridine and benzene rings is 66.87 (3)°. An intramolecular N—H⋯Br hydrogen bond is observed. In the crystal structure, N—H⋯O hydrogen bonds, C—H⋯π interactions and aromatic π–π stacking interactions [centroid–centroid distance = 3.757 (14) Å] link the molecules into a three-dimensional network.

Related literature

The title compound is a key intermediate in the synthesis of new antitumor drugs including TGX221 [systematic name 7-methyl-2-(4-morpholinyl)-9-[1-(phenylamino)ethyl]-4H-pyrido[1,2-a]pyrimidin-4-one]. For the biological activity of TGX221, see: Jackson et al. (2005 ).

Experimental

Crystal data

C₁₃H₁₃BrN₂O₂S
M_r = 341.22
Monoclinic, P 2₁ /c
a = 11.832 (2) Å
b = 13.305 (3) Å
c = 8.6263 (17) Å
β = 105.52 (3)°
V = 1308.5 (5) Å³
Z = 4
Mo Kα radiation
μ = 3.30 mm⁻¹
T = 113 K
0.22 × 0.21 × 0.18 mm

Data collection

Rigaku Saturn CCD area-detector diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005 ) T_min = 0.531, T_max = 0.588
10637 measured reflections
3102 independent reflections
2455 reflections with I > 2σ(I)
R_int = 0.037

Refinement

R[F² > 2σ(F²)] = 0.028
wR(F²) = 0.071
S = 1.03
3102 reflections
178 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.38 e Å⁻³
Δρ_min = −0.66 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 is is the centroid of the N2, C1–C5 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯Br1	0.72 (3)	2.78 (2)	3.134 (2)	114 (2)
N1—H1⋯O1ⁱ	0.72 (3)	2.53 (3)	3.225 (2)	164 (3)
C3—H3⋯Cg1ⁱⁱ	0.95	2.76	3.648 (2)	155
Symmetry codes: (i) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (ii) -x+1, -y+1, -z+2.

Data collection: DIFRAC (Gabe & White, 1993 ); cell refinement: DIFRAC; data reduction: NRCVAX (Gabe et al., 1989 ); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 ) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809054014/rz2394sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809054014/rz2394Isup2.hkl

checkCIF report

Comment top

TGX221, a selective inhibitor of PI3K p110β, and its derivatives are of great importance owing to their wide biological properties (Jackson et al., 2005). We report herein the crystal structure of the title compound, which is one of the key intermediates in our synthetic investigations of new antitumor drugs.

The molecular structure of the title compound is shown in Fig. 1. The dihedral angle between the benzene and pyridine is 66.87 (3)°. The molecular conformation is stabilized by an intramolecular N—H···Br hydrogen bond (Table 1). In the crystal, molecules are linked into a three-dimensional network by intermolecular N—H···O hydrogen bonds and aromatic π–π stacking interactions involving centrosymmetrically related pyridine and benzene rings, with a centroid-to-centroid distance of 3.757 (14) Å. In addition, C—H···π interactions are also present (Table 1; Cg1 is the centroid of the C7–C12 benzene ring).

Related literature top

The title compound is a key intermediate in the synthesis of new antitumor drugs including TGX221, a selective inhibitor of PI3K p110β. For the biological activity of TGX221, see: Jackson et al. (2005).

Experimental top

A mixture of 3-bromo-5-methylpyridin-2-amine (18.6 g, 0.1 mol), 4-methylbenzene-1-sulfonyl chloride (38.2 g, 0.2 mol), and pyridine (7.9 g, 0.10 mol), as a catalyst were charged into a three-necked round-bottomed flask fitted with a mechanical stirrer, a thermometer and a nitrogen inlet. The mixture was stirred vigorously at 100°C for 3 h. After the reactor was cooled to room temperature, the reaction solution was poured into water. The resulting solid was filtered, washed with water, dried and recrystallized from the mixture of hexane:ethyl acetate (3:1 v(v) to get colourless crystals suitable for X-ray analysis.

Computing details top

Data collection: DIFRAC (Gabe & White, 1993); cell refinement: DIFRAC (Gabe & White, 1993); data reduction: NRCVAX (Gabe et al., 1989); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of title compound showing 30% probability displacement ellipsoids and the atom-numbering scheme.

N-(3-Bromo-5-methyl-2-pyridyl)-4-methylbenzenesulfonamide top

Crystal data top

C₁₃H₁₃BrN₂O₂S	F(000) = 688
M_r = 341.22	D_x = 1.732 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 4245 reflections
a = 11.832 (2) Å	θ = 2.3–27.9°
b = 13.305 (3) Å	µ = 3.30 mm⁻¹
c = 8.6263 (17) Å	T = 113 K
β = 105.52 (3)°	Block, colourless
V = 1308.5 (5) Å³	0.22 × 0.21 × 0.18 mm
Z = 4

Data collection top

Rigaku Saturn CCD area-detector diffractometer	3102 independent reflections
Radiation source: rotating anode	2455 reflections with I > 2σ(I)
Confocal monochromator	R_int = 0.037
Detector resolution: 7.31 pixels mm^-1	θ_max = 27.9°, θ_min = 2.4°
ϕ and ω scans	h = −9→15
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005)	k = −17→17
T_min = 0.531, T_max = 0.588	l = −10→11
10637 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)] = 0.028	Hydrogen site location: mixed
wR(F²) = 0.071	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ²(F_o²) + (0.0398P)²] where P = (F_o² + 2F_c²)/3
3102 reflections	(Δ/σ)_max = 0.001
178 parameters	Δρ_max = 0.38 e Å⁻³
0 restraints	Δρ_min = −0.66 e Å⁻³

Crystal data top

C₁₃H₁₃BrN₂O₂S	V = 1308.5 (5) Å³
M_r = 341.22	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 11.832 (2) Å	µ = 3.30 mm⁻¹
b = 13.305 (3) Å	T = 113 K
c = 8.6263 (17) Å	0.22 × 0.21 × 0.18 mm
β = 105.52 (3)°

Data collection top

Rigaku Saturn CCD area-detector diffractometer	3102 independent reflections
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005)	2455 reflections with I > 2σ(I)
T_min = 0.531, T_max = 0.588	R_int = 0.037
10637 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.028	0 restraints
wR(F²) = 0.071	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.38 e Å⁻³
3102 reflections	Δρ_min = −0.66 e Å⁻³
178 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	0.542001 (19)	0.267131 (17)	1.09928 (3)	0.01935 (8)
S1	0.23555 (5)	0.35572 (4)	0.64144 (6)	0.01313 (13)
O1	0.27402 (13)	0.33591 (11)	0.50006 (17)	0.0180 (3)
O2	0.14905 (13)	0.29181 (11)	0.67992 (18)	0.0174 (3)
N1	0.34782 (16)	0.34723 (14)	0.8024 (2)	0.0142 (4)
H1	0.339 (2)	0.312 (2)	0.861 (3)	0.026 (8)*
N2	0.46548 (15)	0.46217 (13)	0.7147 (2)	0.0143 (4)
C1	0.45737 (17)	0.39383 (15)	0.8237 (2)	0.0118 (4)
C2	0.55266 (18)	0.36978 (14)	0.9520 (2)	0.0119 (4)
C3	0.65784 (18)	0.42026 (15)	0.9708 (2)	0.0146 (4)
H3	0.7229	0.4056	1.0598	0.018*
C4	0.66762 (18)	0.49303 (15)	0.8579 (2)	0.0137 (4)
C5	0.56853 (19)	0.50966 (15)	0.7326 (2)	0.0146 (4)
H5	0.5736	0.5580	0.6537	0.018*
C6	0.77966 (19)	0.55118 (16)	0.8732 (3)	0.0194 (5)
H6A	0.7756	0.5862	0.7719	0.029*
H6B	0.8463	0.5047	0.8971	0.029*
H6C	0.7898	0.6004	0.9604	0.029*
C7	0.18506 (18)	0.48129 (15)	0.6312 (2)	0.0131 (4)
C8	0.09300 (18)	0.50427 (16)	0.6980 (2)	0.0135 (4)
H8	0.0581	0.4534	0.7471	0.016*
C9	0.05321 (18)	0.60313 (16)	0.6914 (2)	0.0158 (4)
H9	−0.0099	0.6193	0.7356	0.019*
C10	0.10400 (19)	0.67832 (15)	0.6215 (2)	0.0150 (4)
C11	0.19340 (19)	0.65226 (16)	0.5508 (3)	0.0166 (5)
H11	0.2269	0.7027	0.4990	0.020*
C12	0.23404 (18)	0.55464 (16)	0.5549 (2)	0.0154 (4)
H12	0.2947	0.5380	0.5061	0.018*
C13	0.0635 (2)	0.78579 (17)	0.6201 (3)	0.0216 (5)
H13A	0.1296	0.8283	0.6755	0.032*
H13B	0.0012	0.7903	0.6753	0.032*
H13C	0.0332	0.8086	0.5087	0.032*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.01556 (13)	0.02025 (13)	0.02032 (14)	−0.00270 (9)	0.00147 (9)	0.00962 (9)
S1	0.0115 (3)	0.0124 (2)	0.0134 (3)	0.0010 (2)	−0.0002 (2)	−0.00113 (19)
O1	0.0207 (8)	0.0192 (8)	0.0133 (8)	0.0031 (7)	0.0029 (7)	−0.0030 (6)
O2	0.0123 (8)	0.0144 (7)	0.0235 (9)	−0.0028 (6)	0.0011 (7)	0.0003 (6)
N1	0.0114 (9)	0.0164 (9)	0.0135 (10)	−0.0018 (8)	0.0009 (8)	0.0047 (8)
N2	0.0138 (9)	0.0157 (9)	0.0130 (8)	0.0020 (7)	0.0026 (7)	0.0018 (7)
C1	0.0119 (10)	0.0119 (10)	0.0124 (10)	0.0006 (8)	0.0047 (8)	−0.0027 (8)
C2	0.0144 (10)	0.0104 (9)	0.0119 (10)	−0.0005 (8)	0.0051 (8)	−0.0003 (8)
C3	0.0130 (10)	0.0157 (10)	0.0128 (11)	0.0001 (9)	−0.0005 (9)	−0.0014 (8)
C4	0.0156 (11)	0.0120 (10)	0.0139 (10)	−0.0011 (9)	0.0049 (9)	−0.0005 (8)
C5	0.0187 (11)	0.0115 (10)	0.0148 (10)	−0.0006 (9)	0.0063 (9)	0.0027 (8)
C6	0.0170 (12)	0.0192 (11)	0.0218 (12)	−0.0034 (10)	0.0051 (9)	0.0039 (9)
C7	0.0121 (10)	0.0133 (10)	0.0115 (10)	0.0018 (8)	−0.0008 (8)	0.0001 (8)
C8	0.0108 (10)	0.0167 (10)	0.0123 (10)	−0.0011 (9)	0.0019 (8)	0.0001 (8)
C9	0.0117 (10)	0.0215 (11)	0.0140 (11)	0.0019 (9)	0.0031 (9)	−0.0023 (9)
C10	0.0141 (11)	0.0141 (11)	0.0138 (11)	0.0017 (9)	−0.0015 (9)	−0.0011 (8)
C11	0.0138 (11)	0.0173 (11)	0.0177 (11)	−0.0007 (9)	0.0026 (9)	0.0025 (9)
C12	0.0120 (10)	0.0201 (11)	0.0141 (11)	0.0013 (9)	0.0036 (9)	0.0008 (8)
C13	0.0206 (12)	0.0172 (12)	0.0242 (13)	0.0015 (9)	0.0009 (10)	−0.0009 (9)

Geometric parameters (Å, º) top

Br1—C2	1.8925 (19)	C6—H6B	0.9800
S1—O1	1.4357 (15)	C6—H6C	0.9800
S1—O2	1.4361 (15)	C7—C12	1.388 (3)
S1—N1	1.649 (2)	C7—C8	1.396 (3)
S1—C7	1.768 (2)	C8—C9	1.393 (3)
N1—C1	1.404 (3)	C8—H8	0.9500
N1—H1	0.72 (2)	C9—C10	1.385 (3)
N2—C1	1.330 (2)	C9—H9	0.9500
N2—C5	1.345 (3)	C10—C11	1.399 (3)
C1—C2	1.389 (3)	C10—C13	1.507 (3)
C2—C3	1.385 (3)	C11—C12	1.382 (3)
C3—C4	1.400 (3)	C11—H11	0.9500
C3—H3	0.9500	C12—H12	0.9500
C4—C5	1.384 (3)	C13—H13A	0.9800
C4—C6	1.510 (3)	C13—H13B	0.9800
C5—H5	0.9500	C13—H13C	0.9800
C6—H6A	0.9800

O1—S1—O2	119.68 (9)	C4—C6—H6C	109.5
O1—S1—N1	109.63 (9)	H6A—C6—H6C	109.5
O2—S1—N1	103.19 (9)	H6B—C6—H6C	109.5
O1—S1—C7	108.09 (9)	C12—C7—C8	120.86 (19)
O2—S1—C7	108.59 (10)	C12—C7—S1	120.64 (16)
N1—S1—C7	106.98 (9)	C8—C7—S1	118.48 (15)
C1—N1—S1	125.99 (15)	C9—C8—C7	118.85 (19)
C1—N1—H1	120 (2)	C9—C8—H8	120.6
S1—N1—H1	113 (2)	C7—C8—H8	120.6
C1—N2—C5	118.33 (18)	C10—C9—C8	121.23 (19)
N2—C1—C2	121.59 (19)	C10—C9—H9	119.4
N2—C1—N1	116.62 (18)	C8—C9—H9	119.4
C2—C1—N1	121.79 (18)	C9—C10—C11	118.52 (19)
C3—C2—C1	119.62 (18)	C9—C10—C13	120.96 (19)
C3—C2—Br1	119.36 (15)	C11—C10—C13	120.53 (19)
C1—C2—Br1	121.01 (15)	C12—C11—C10	121.4 (2)
C2—C3—C4	119.51 (19)	C12—C11—H11	119.3
C2—C3—H3	120.2	C10—C11—H11	119.3
C4—C3—H3	120.2	C11—C12—C7	119.1 (2)
C5—C4—C3	116.35 (19)	C11—C12—H12	120.5
C5—C4—C6	121.78 (18)	C7—C12—H12	120.5
C3—C4—C6	121.87 (19)	C10—C13—H13A	109.5
N2—C5—C4	124.57 (19)	C10—C13—H13B	109.5
N2—C5—H5	117.7	H13A—C13—H13B	109.5
C4—C5—H5	117.7	C10—C13—H13C	109.5
C4—C6—H6A	109.5	H13A—C13—H13C	109.5
C4—C6—H6B	109.5	H13B—C13—H13C	109.5
H6A—C6—H6B	109.5

O1—S1—N1—C1	49.3 (2)	C6—C4—C5—N2	−178.28 (18)
O2—S1—N1—C1	177.92 (17)	O1—S1—C7—C12	−31.16 (19)
C7—S1—N1—C1	−67.63 (19)	O2—S1—C7—C12	−162.43 (16)
C5—N2—C1—C2	−1.2 (3)	N1—S1—C7—C12	86.82 (18)
C5—N2—C1—N1	178.89 (17)	O1—S1—C7—C8	147.25 (15)
S1—N1—C1—N2	10.4 (3)	O2—S1—C7—C8	15.98 (18)
S1—N1—C1—C2	−169.47 (15)	N1—S1—C7—C8	−94.77 (17)
N2—C1—C2—C3	2.3 (3)	C12—C7—C8—C9	−2.0 (3)
N1—C1—C2—C3	−177.83 (18)	S1—C7—C8—C9	179.57 (15)
N2—C1—C2—Br1	−176.47 (15)	C7—C8—C9—C10	−0.6 (3)
N1—C1—C2—Br1	3.4 (3)	C8—C9—C10—C11	2.8 (3)
C1—C2—C3—C4	−1.7 (3)	C8—C9—C10—C13	−177.77 (19)
Br1—C2—C3—C4	177.10 (14)	C9—C10—C11—C12	−2.4 (3)
C2—C3—C4—C5	0.1 (3)	C13—C10—C11—C12	178.16 (19)
C2—C3—C4—C6	179.38 (19)	C10—C11—C12—C7	−0.2 (3)
C1—N2—C5—C4	−0.4 (3)	C8—C7—C12—C11	2.4 (3)
C3—C4—C5—N2	1.0 (3)	S1—C7—C12—C11	−179.22 (16)

Hydrogen-bond geometry (Å, º) top

Cg2 is is the centroid of the N2, C1–C5 ring.

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···Br1	0.72 (3)	2.78 (2)	3.134 (2)	114 (2)
N1—H1···O1ⁱ	0.72 (3)	2.53 (3)	3.225 (2)	164 (3)
C3—H3···Cg1ⁱⁱ	0.95	2.76	3.648 (2)	155

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

Experimental details

Crystal data
Chemical formula	C₁₃H₁₃BrN₂O₂S
M_r	341.22
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	113
a, b, c (Å)	11.832 (2), 13.305 (3), 8.6263 (17)
β (°)	105.52 (3)
V (Å³)	1308.5 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	3.30
Crystal size (mm)	0.22 × 0.21 × 0.18

Data collection
Diffractometer	Rigaku Saturn CCD area-detector diffractometer
Absorption correction	Multi-scan (CrystalClear; Rigaku/MSC, 2005)
T_min, T_max	0.531, 0.588
No. of measured, independent and observed [I > 2σ(I)] reflections	10637, 3102, 2455
R_int	0.037
(sin θ/λ)_max (Å⁻¹)	0.657

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.028, 0.071, 1.03
No. of reflections	3102
No. of parameters	178
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.38, −0.66

Computer programs: DIFRAC (Gabe & White, 1993), NRCVAX (Gabe et al., 1989), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996) and Mercury (Macrae et al., 2006).

Hydrogen-bond geometry (Å, º) top

Cg2 is is the centroid of the N2, C1–C5 ring.

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···Br1	0.72 (3)	2.78 (2)	3.134 (2)	114 (2)
N1—H1···O1ⁱ	0.72 (3)	2.53 (3)	3.225 (2)	164 (3)
C3—H3···Cg1ⁱⁱ	0.95	2.76	3.648 (2)	155

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

Acknowledgements

The authors thank Mr·Zhi-Hua Mao of Sichuan University for the X-ray data collection.

References

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Volume 66| Part 1| January 2010| Page o205

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