5-Bromo-4-(3,4-dimeth­oxy­phen­yl)thia­zol-2-amine

Ghabbour, H.A.; Chia, T.S.; Fun, H.-K.

doi:10.1107/S1600536812019320

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 68| Part 6| June 2012| Pages o1631-o1632

doi:10.1107/S1600536812019320

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5-Bromo-4-(3,4-dimethoxyphenyl)thiazol-2-amine

Hazem A. Ghabbour,^a Tze Shyang Chia ^b and Hoong-Kun Fun ^b ^*‡

^aDepartment of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, PO Box 2457, Riyadh 11451, Saudi Arabia, and ^bX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
^*Correspondence e-mail: hkfun@usm.my

(Received 28 April 2012; accepted 30 April 2012; online 5 May 2012)

In the title compound, C₁₁H₁₁BrN₂O₂S, the thiazole ring makes a dihedral angle of 53.16 (11)° with the adjacent benzene ring. The two methoxy groups are slightly twisted from the attached benzene ring with C—O—C—C torsion angles of −9.2 (3) and −5.5 (3)°. In the crystal, molecules are linked by a pair of N—H⋯N hydrogen bonds into an inversion dimer with an R₂²(8) ring motif. The dimers are further connected by N—H⋯O hydrogen bonds into a tape along [-110].

Related literature

For applications of the thiazole ring system, see: Hargrave et al. (1983 ); Patt et al. (1992 ); Haviv et al. (1988 ); Jaen et al. (1990 ); Tsuji & Ishikawa (1994 ); Bell et al. (1995 ). For applications of aminothiazoles, see: Fink et al. (1999 ); Van Muijlwijk-Koezen et al. (2001 ); Metzger (1984 ). For hydrogen-bond motifs, see: Bernstein et al. (1995 ). For the preparation, see: Das et al. (2006 ). For stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 ).

Experimental

Crystal data

C₁₁H₁₁BrN₂O₂S
M_r = 315.19
Triclinic, $[P \overline 1]$
a = 7.4873 (2) Å
b = 8.0359 (2) Å
c = 10.6428 (3) Å
α = 86.571 (2)°
β = 77.633 (2)°
γ = 85.330 (2)°
V = 622.82 (3) Å³
Z = 2
Mo Kα radiation
μ = 3.46 mm⁻¹
T = 100 K
0.45 × 0.20 × 0.09 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.305, T_max = 0.737
10861 measured reflections
2121 independent reflections
1888 reflections with I > 2σ(I)
R_int = 0.030

Refinement

R[F² > 2σ(F²)] = 0.024
wR(F²) = 0.071
S = 1.12
2121 reflections
164 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 1.17 e Å⁻³
Δρ_min = −0.73 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2N2⋯O1ⁱ	0.78 (3)	2.40 (3)	2.992 (3)	134 (3)
N2—H2N2⋯O2ⁱ	0.78 (3)	2.37 (3)	3.112 (3)	161 (3)
N2—H1N2⋯N1ⁱⁱ	0.81 (3)	2.20 (3)	2.998 (3)	168 (3)
Symmetry codes: (i) x-1, y+1, z; (ii) -x, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812019320/is5132sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812019320/is5132Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812019320/is5132Isup3.cml

checkCIF report

Comment top

The thiazole ring system is a useful structural motif found in numerous biologically active molecules. This structure has found applications in drug development for the treatment of allergies (Hargrave et al., 1983), hypertension (Patt et al., 1992), inflammation (Haviv et al., 1988), schizophrenia (Jaen et al., 1990), bacterial (Tsuji & Ishikawa, 1994) and HIV infections (Bell et al., 1995). Aminothiazoles are known to be ligands of estrogen receptors (Fink et al., 1999) as well as a novel class of adenosine receptor antagonists (Van Muijlwijk-Koezen et al., 2001). Other analogues are used as fungicides, inhibiting in vivo growth of Xanthomonas, as an ingredient of herbicides or as schistosomicidal and anthelmintic drugs (Metzger, 1984).

In the title compound (Fig. 1), the thiazole ring (S1/N1/C7–C9) makes a dihedral angle of 53.16 (11)° with the adjacent benzene ring (C1–C6). The two methoxy groups (O1/C10 & O2/C11) are slightly twisted from the C1–C6 ring with torsion angles C10—O1—C3—C2 = -9.2 (3) and C11—O2—C4—C5 = -5.5 (3)°.

In the crystal packing (Fig. 2 & 3), the molecules are linked by intermolecular N2—H1N2···N1 hydrogen bonds into dimers with R₂²(8) ring motifs (Bernstein et al., 1995). The dimers are further connected by intermolecular N2—H2N2···O1 and N2—H2N2···O2 hydrogen bonds (Table 1) into infinite tapes along [110].

Related literature top

For applications of the thiazole ring system, see: Hargrave et al. (1983); Patt et al. (1992); Haviv et al. (1988); Jaen et al. (1990); Tsuji & Ishikawa (1994); Bell et al. (1995). For applications of aminothiazoles, see: Fink et al. (1999); Van Muijlwijk-Koezen et al. (2001); Metzger (1984). For hydrogen-bond motifs, see: Bernstein et al. (1995). For the preparation, see: Das et al. (2006). For stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Experimental top

The title compound was prepared from the reaction of 4-(3,4-dimethoxyphenyl)thiazol-2-amine (236 mg, 1 mmol) with bromine (161 mg, 1.1 mmol) in glacial acetic acid and heated at 80 °C for 1.5 h. Single crystals of the title compound suitable for X-ray structure determination were recrystallized from ethanol by the slow evaporation of the solvent at room temperature after several days (Das et al., 2006).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of the title compound with atom labels and 50% probability displacement ellipsoids.
	Fig. 2. The crystal packing of the title compound. The dashed lines represent the hydrogen bonds. For clarity sake, hydrogen atoms not involved in hydrogen bonding have been omitted.
	Fig. 3. The crystal packing of the title compound viewed along [1 1 0].

5-Bromo-4-(3,4-dimethoxyphenyl)thiazol-2-amine top

Crystal data top

C₁₁H₁₁BrN₂O₂S	Z = 2
M_r = 315.19	F(000) = 316
Triclinic, P1	D_x = 1.681 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.4873 (2) Å	Cell parameters from 7495 reflections
b = 8.0359 (2) Å	θ = 2.6–35.5°
c = 10.6428 (3) Å	µ = 3.46 mm⁻¹
α = 86.571 (2)°	T = 100 K
β = 77.633 (2)°	Plate, brown
γ = 85.330 (2)°	0.45 × 0.20 × 0.09 mm
V = 622.82 (3) Å³

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	2121 independent reflections
Radiation source: fine-focus sealed tube	1888 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.030
ϕ and ω scans	θ_max = 25.0°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −8→8
T_min = 0.305, T_max = 0.737	k = −9→9
10861 measured reflections	l = −12→12

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)] = 0.024	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.071	H atoms treated by a mixture of independent and constrained refinement
S = 1.12	w = 1/[σ²(F_o²) + (0.0446P)² + 0.1359P] where P = (F_o² + 2F_c²)/3
2121 reflections	(Δ/σ)_max = 0.002
164 parameters	Δρ_max = 1.17 e Å⁻³
0 restraints	Δρ_min = −0.73 e Å⁻³

Crystal data top

C₁₁H₁₁BrN₂O₂S	γ = 85.330 (2)°
M_r = 315.19	V = 622.82 (3) Å³
Triclinic, P1	Z = 2
a = 7.4873 (2) Å	Mo Kα radiation
b = 8.0359 (2) Å	µ = 3.46 mm⁻¹
c = 10.6428 (3) Å	T = 100 K
α = 86.571 (2)°	0.45 × 0.20 × 0.09 mm
β = 77.633 (2)°

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	2121 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	1888 reflections with I > 2σ(I)
T_min = 0.305, T_max = 0.737	R_int = 0.030
10861 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.024	0 restraints
wR(F²) = 0.071	H atoms treated by a mixture of independent and constrained refinement
S = 1.12	Δρ_max = 1.17 e Å⁻³
2121 reflections	Δρ_min = −0.73 e Å⁻³
164 parameters

Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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	−0.16418 (3)	0.27703 (3)	1.04837 (2)	0.02360 (12)
S1	−0.30599 (8)	0.51061 (8)	0.84026 (6)	0.01865 (17)
O1	0.6319 (2)	−0.1031 (2)	0.74403 (16)	0.0203 (4)
O2	0.4088 (2)	−0.1521 (2)	0.60126 (16)	0.0213 (4)
N1	−0.0368 (3)	0.4074 (3)	0.6600 (2)	0.0187 (5)
N2	−0.2487 (4)	0.5970 (3)	0.5852 (2)	0.0237 (5)
C1	0.2811 (3)	0.2379 (3)	0.8495 (2)	0.0195 (6)
H1A	0.2539	0.3246	0.9090	0.023*
C2	0.4415 (3)	0.1345 (3)	0.8433 (2)	0.0193 (6)
H2A	0.5241	0.1524	0.8968	0.023*
C3	0.4794 (3)	0.0060 (3)	0.7588 (2)	0.0168 (5)
C4	0.3576 (3)	−0.0193 (3)	0.6795 (2)	0.0162 (5)
C5	0.2018 (3)	0.0867 (3)	0.6835 (2)	0.0166 (5)
H5A	0.1218	0.0719	0.6274	0.020*
C6	0.1613 (3)	0.2164 (3)	0.7706 (2)	0.0169 (5)
C7	−0.0059 (3)	0.3294 (3)	0.7743 (2)	0.0167 (5)
C8	−0.1867 (3)	0.5072 (3)	0.6792 (2)	0.0180 (6)
C9	−0.1366 (3)	0.3686 (3)	0.8796 (2)	0.0174 (5)
C10	0.7724 (3)	−0.0657 (3)	0.8075 (2)	0.0233 (6)
H10A	0.8799	−0.1439	0.7821	0.035*
H10B	0.7274	−0.0762	0.9010	0.035*
H10C	0.8065	0.0488	0.7831	0.035*
C11	0.2828 (4)	−0.1928 (4)	0.5250 (3)	0.0260 (6)
H11A	0.3359	−0.2877	0.4723	0.039*
H11B	0.2589	−0.0961	0.4689	0.039*
H11C	0.1675	−0.2225	0.5819	0.039*
H2N2	−0.324 (4)	0.669 (4)	0.602 (3)	0.028 (9)*
H1N2	−0.182 (4)	0.606 (4)	0.515 (3)	0.033 (9)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.02354 (18)	0.02661 (19)	0.01783 (16)	0.00291 (11)	−0.00083 (11)	0.00253 (12)
S1	0.0173 (3)	0.0182 (4)	0.0182 (3)	0.0037 (3)	−0.0003 (3)	−0.0012 (3)
O1	0.0161 (9)	0.0188 (10)	0.0266 (9)	0.0041 (7)	−0.0071 (7)	−0.0039 (8)
O2	0.0207 (9)	0.0200 (10)	0.0238 (9)	0.0045 (8)	−0.0060 (8)	−0.0086 (8)
N1	0.0190 (11)	0.0185 (12)	0.0178 (10)	0.0028 (9)	−0.0033 (9)	−0.0020 (9)
N2	0.0244 (14)	0.0241 (15)	0.0187 (12)	0.0125 (11)	−0.0005 (10)	−0.0019 (11)
C1	0.0203 (14)	0.0167 (14)	0.0208 (12)	−0.0003 (11)	−0.0019 (10)	−0.0048 (11)
C2	0.0187 (13)	0.0199 (15)	0.0202 (13)	−0.0014 (11)	−0.0057 (10)	−0.0008 (11)
C3	0.0142 (13)	0.0132 (13)	0.0209 (12)	0.0013 (10)	−0.0003 (10)	0.0021 (10)
C4	0.0178 (13)	0.0135 (14)	0.0152 (11)	−0.0001 (10)	0.0006 (10)	−0.0003 (10)
C5	0.0172 (13)	0.0173 (14)	0.0149 (11)	−0.0009 (10)	−0.0029 (10)	0.0007 (10)
C6	0.0188 (13)	0.0137 (13)	0.0162 (11)	−0.0003 (10)	−0.0001 (10)	0.0030 (10)
C7	0.0175 (13)	0.0136 (13)	0.0190 (12)	−0.0011 (10)	−0.0039 (10)	−0.0008 (11)
C8	0.0193 (14)	0.0170 (14)	0.0171 (12)	0.0013 (11)	−0.0030 (10)	−0.0024 (11)
C9	0.0192 (13)	0.0136 (14)	0.0183 (12)	0.0021 (10)	−0.0035 (10)	0.0017 (11)
C10	0.0140 (13)	0.0262 (16)	0.0296 (14)	0.0026 (11)	−0.0050 (11)	−0.0034 (12)
C11	0.0263 (15)	0.0265 (16)	0.0270 (14)	0.0004 (12)	−0.0080 (12)	−0.0097 (12)

Geometric parameters (Å, º) top

Br1—C9	1.876 (2)	C2—C3	1.382 (3)
S1—C9	1.738 (3)	C2—H2A	0.9500
S1—C8	1.755 (2)	C3—C4	1.402 (3)
O1—C3	1.369 (3)	C4—C5	1.382 (4)
O1—C10	1.426 (3)	C5—C6	1.407 (3)
O2—C4	1.372 (3)	C5—H5A	0.9500
O2—C11	1.437 (3)	C6—C7	1.480 (4)
N1—C8	1.312 (3)	C7—C9	1.355 (3)
N1—C7	1.390 (3)	C10—H10A	0.9800
N2—C8	1.340 (4)	C10—H10B	0.9800
N2—H2N2	0.78 (3)	C10—H10C	0.9800
N2—H1N2	0.80 (3)	C11—H11A	0.9800
C1—C6	1.380 (3)	C11—H11B	0.9800
C1—C2	1.395 (4)	C11—H11C	0.9800
C1—H1A	0.9500

C9—S1—C8	88.28 (12)	C1—C6—C7	121.1 (2)
C3—O1—C10	116.65 (19)	C5—C6—C7	119.8 (2)
C4—O2—C11	117.3 (2)	C9—C7—N1	114.3 (2)
C8—N1—C7	111.7 (2)	C9—C7—C6	126.9 (2)
C8—N2—H2N2	120 (2)	N1—C7—C6	118.7 (2)
C8—N2—H1N2	119 (2)	N1—C8—N2	123.9 (2)
H2N2—N2—H1N2	116 (3)	N1—C8—S1	114.24 (19)
C6—C1—C2	121.1 (2)	N2—C8—S1	121.9 (2)
C6—C1—H1A	119.4	C7—C9—S1	111.44 (19)
C2—C1—H1A	119.4	C7—C9—Br1	128.9 (2)
C3—C2—C1	119.6 (2)	S1—C9—Br1	119.41 (13)
C3—C2—H2A	120.2	O1—C10—H10A	109.5
C1—C2—H2A	120.2	O1—C10—H10B	109.5
O1—C3—C2	124.9 (2)	H10A—C10—H10B	109.5
O1—C3—C4	115.1 (2)	O1—C10—H10C	109.5
C2—C3—C4	120.0 (2)	H10A—C10—H10C	109.5
O2—C4—C5	125.4 (2)	H10B—C10—H10C	109.5
O2—C4—C3	114.6 (2)	O2—C11—H11A	109.5
C5—C4—C3	120.1 (2)	O2—C11—H11B	109.5
C4—C5—C6	120.1 (2)	H11A—C11—H11B	109.5
C4—C5—H5A	119.9	O2—C11—H11C	109.5
C6—C5—H5A	119.9	H11A—C11—H11C	109.5
C1—C6—C5	119.1 (2)	H11B—C11—H11C	109.5

C6—C1—C2—C3	−1.4 (4)	C8—N1—C7—C9	1.5 (3)
C10—O1—C3—C2	−9.2 (3)	C8—N1—C7—C6	−178.0 (2)
C10—O1—C3—C4	170.4 (2)	C1—C6—C7—C9	−52.8 (4)
C1—C2—C3—O1	179.9 (2)	C5—C6—C7—C9	128.5 (3)
C1—C2—C3—C4	0.3 (4)	C1—C6—C7—N1	126.6 (2)
C11—O2—C4—C5	−5.5 (3)	C5—C6—C7—N1	−52.1 (3)
C11—O2—C4—C3	175.2 (2)	C7—N1—C8—N2	−179.6 (2)
O1—C3—C4—O2	1.3 (3)	C7—N1—C8—S1	−1.3 (3)
C2—C3—C4—O2	−179.1 (2)	C9—S1—C8—N1	0.6 (2)
O1—C3—C4—C5	−178.0 (2)	C9—S1—C8—N2	179.0 (2)
C2—C3—C4—C5	1.6 (4)	N1—C7—C9—S1	−1.0 (3)
O2—C4—C5—C6	178.4 (2)	C6—C7—C9—S1	178.36 (19)
C3—C4—C5—C6	−2.4 (3)	N1—C7—C9—Br1	172.86 (17)
C2—C1—C6—C5	0.6 (4)	C6—C7—C9—Br1	−7.7 (4)
C2—C1—C6—C7	−178.1 (2)	C8—S1—C9—C7	0.28 (19)
C4—C5—C6—C1	1.3 (3)	C8—S1—C9—Br1	−174.28 (14)
C4—C5—C6—C7	−180.0 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2N2···O1ⁱ	0.78 (3)	2.40 (3)	2.992 (3)	134 (3)
N2—H2N2···O2ⁱ	0.78 (3)	2.37 (3)	3.112 (3)	161 (3)
N2—H1N2···N1ⁱⁱ	0.81 (3)	2.20 (3)	2.998 (3)	168 (3)

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

Experimental details

Crystal data
Chemical formula	C₁₁H₁₁BrN₂O₂S
M_r	315.19
Crystal system, space group	Triclinic, P1
Temperature (K)	100
a, b, c (Å)	7.4873 (2), 8.0359 (2), 10.6428 (3)
α, β, γ (°)	86.571 (2), 77.633 (2), 85.330 (2)
V (Å³)	622.82 (3)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	3.46
Crystal size (mm)	0.45 × 0.20 × 0.09

Data collection
Diffractometer	Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.305, 0.737
No. of measured, independent and observed [I > 2σ(I)] reflections	10861, 2121, 1888
R_int	0.030
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.024, 0.071, 1.12
No. of reflections	2121
No. of parameters	164
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	1.17, −0.73

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2N2···O1ⁱ	0.78 (3)	2.40 (3)	2.992 (3)	134 (3)
N2—H2N2···O2ⁱ	0.78 (3)	2.37 (3)	3.112 (3)	161 (3)
N2—H1N2···N1ⁱⁱ	0.81 (3)	2.20 (3)	2.998 (3)	168 (3)

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

Footnotes

‡Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

HAG thanks the Deanship of Scientific Research and Research Center, College of Pharmacy, King Saud University. HKF and TSC thank Universiti Sains Malaysia (USM) for the Research University Grant (1001/PFIZIK/811160). TSC also thanks the Malaysian Government and USM for the award of a research fellowship.

References

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