5-(4-Bromo-2-nitro­phen­yl)-1,3,4-thia­diazol-2-amine

Abstract

The title compound, C₈H₅BrN₄O₂S, was synthesized by the reaction of 4-bromo-2-nitro­benzoic acid with thio­semi­carbazide. The dihedral angle between the thia­diazole and benzene rings is 40.5 (2)°. In the crystal, the strongest N—H⋯N inter­molecular hydrogen bond, between the amine group and one thia­diazole N atom, forms centrosymmetric dimers. The other amine H atom extends the supra­molecular network, forming an N—H⋯N contact with the other thia­diazole N atom.

Related literature

For the biological activity of 1,3,4-thia­diazole derivatives, see: Nakagawa et al. (1996 ▶); Wang et al. (1999 ▶).

Experimental

Crystal data

• C₈H₅BrN₄O₂S

• M _r = 301.13

• Monoclinic,

• a = 11.231 (2) Å

• b = 9.2580 (19) Å

• c = 10.868 (2) Å

• β = 113.08 (3)°

• V = 1039.6 (4) ų

• Z = 4

• Mo Kα radiation

• μ = 4.14 mm⁻¹

• T = 293 K

• 0.20 × 0.10 × 0.10 mm

Data collection

• Enraf–Nonius CAD-4 diffractometer

• Absorption correction: ψ scan (North et al., 1968 ▶) T _min = 0.491, T _max = 0.682

• 3909 measured reflections

• 1920 independent reflections

• 1409 reflections with I > 2σ(I)

• R _int = 0.116

• 3 standard reflections every 200 reflections intensity decay: 1%

Refinement

• R[F ² > 2σ(F ²)] = 0.049

• wR(F ²) = 0.104

• S = 1.01

• 1920 reflections

• 152 parameters

• H atoms treated by a mixture of independent and constrained refinement

• Δρ_max = 0.55 e Å⁻³

• Δρ_min = −0.97 e Å⁻³

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1989 ▶); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo,1995 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Supplementary material file. DOI: 10.1107/S1600536811030868/bh2371Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N4—H4B⋯N3i	0.79 (7)	2.25 (7)	3.014 (6)	165 (7)
N4—H4C⋯N2ii	0.80 (6)	2.34 (6)	3.103 (6)	161 (6)

Symmetry codes: (i) ; (ii) .

supplementary crystallographic information

Comment

1,3,4-Thiadiazole derivatives represent an interesting class of compounds possessing a broad spectrum of biological activities (Nakagawa et al., 1996). These compounds are known to exhibit diverse biological activities, such as insecticidal and fungicidal activities (Wang et al., 1999). Here we report the crystal structure of the title compound, a new thiadiazole. In the molecular structure (Fig. 1) the bond lengths and angles are within normal ranges. Thiadiazole ring C8/S/C7/N2/N3 is planar, and the mean deviation from the plane is 0.0046 Å. The dihedral angle between the thiadiazole and benzene rings is 40.5 (2)°. In the crystal structure, the strongest N—H···N intermolecular contact (first entry in the hydrogen bonds Table) forms centrosymmetric dimers in the crystal (top molecules in Fig. 2). This pattern is the primary supramolecular structure for this compound. The other hydrogen bond (entry 2) is comparatively weak, and extends the primary pattern to a three-dimensional network, which may be effective in the stabilization of the crystal structure.

Experimental

4-Bromo-2-nitrobenzoic acid (2 mmol) and thiosemicarbazide (5 mmol) were mixed in a 25 ml flask, and kept in the oil bath at 90 °C for 6 h. After cooling, the crude product precipitated and was filtered. Pure compound was obtained by crystallization from ethanol (20 ml). Single crystals suitable for X-ray diffraction were obtained by slow evaporation of an acetone solution.

Refinement

All H atoms bonded to the C atoms were placed geometrically at the distances of 0.93 Å and included in the refinement in riding motion approximation with U_iso(H) = 1.2U_eq(carrier C atom). Amine H atoms H4B and H4C were found in a difference map and refined freely, with U_iso(H) = 1.2U_eq(N4).

Figures

Fig. 1.

A view of the molecular structure of the title compound, with displacement ellipsoids drawn at the 50% probability level.

Fig. 2.

Partial packing view showing the hydrogen bonds network. Dashed lines indicate intermolecular N—H···N hydrogen bonds.

Crystal data

C8H5BrN4O2S	F(000) = 592
Mr = 301.13	Dx = 1.924 Mg m−3
Monoclinic, P21/c	Melting point: 506 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 11.231 (2) Å	Cell parameters from 25 reflections
b = 9.2580 (19) Å	θ = 10–13°
c = 10.868 (2) Å	µ = 4.14 mm−1
β = 113.08 (3)°	T = 293 K
V = 1039.6 (4) Å3	Block, yellow
Z = 4	0.20 × 0.10 × 0.10 mm

Data collection

Enraf–Nonius CAD-4 diffractometer	1409 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.116
graphite	θmax = 25.4°, θmin = 2.0°
ω/2θ scans	h = −13→12
Absorption correction: ψ scan (North et al., 1968)	k = −11→11
Tmin = 0.491, Tmax = 0.682	l = 0→13
3909 measured reflections	3 standard reflections every 200 reflections
1920 independent reflections	intensity decay: 1%

Refinement

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.049	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.104	w = 1/[σ2(Fo2) + (0.025P)2] where P = (Fo2 + 2Fc2)/3
S = 1.01	(Δ/σ)max < 0.001
1920 reflections	Δρmax = 0.55 e Å−3
152 parameters	Δρmin = −0.97 e Å−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 constraints	Extinction coefficient: 0.0114 (8)
Primary atom site location: structure-invariant direct methods

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Br	0.11486 (5)	0.01063 (5)	0.19612 (6)	0.0512 (2)
S	0.34305 (13)	0.66328 (12)	0.58298 (11)	0.0389 (3)
C1	0.2933 (5)	0.3456 (5)	0.4493 (4)	0.0398 (11)
H1A	0.3437	0.3551	0.5402	0.048*
N1	0.1367 (4)	0.5710 (4)	0.1441 (4)	0.0370 (9)
O1	0.1374 (4)	0.5588 (4)	0.0330 (3)	0.0585 (10)
O2	0.0937 (3)	0.6740 (3)	0.1818 (3)	0.0517 (10)
N2	0.3728 (4)	0.6948 (4)	0.3620 (3)	0.0357 (9)
C2	0.2492 (5)	0.2112 (5)	0.3991 (5)	0.0418 (12)
H2B	0.2717	0.1308	0.4549	0.050*
N3	0.4262 (4)	0.8176 (4)	0.4373 (3)	0.0339 (9)
C3	0.1724 (4)	0.1958 (4)	0.2670 (5)	0.0360 (10)
C4	0.1413 (5)	0.3137 (5)	0.1816 (4)	0.0339 (11)
H4A	0.0920	0.3029	0.0907	0.041*
N4	0.4674 (5)	0.9189 (5)	0.6472 (4)	0.0460 (12)
H4B	0.486 (6)	0.996 (7)	0.630 (6)	0.055*
H4C	0.446 (5)	0.910 (6)	0.709 (6)	0.055*
C5	0.1853 (4)	0.4459 (5)	0.2350 (4)	0.0331 (10)
C6	0.2654 (4)	0.4671 (4)	0.3696 (4)	0.0283 (9)
C7	0.3245 (4)	0.6062 (5)	0.4235 (4)	0.0303 (9)
C8	0.4186 (4)	0.8148 (4)	0.5534 (4)	0.0318 (10)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Br	0.0612 (3)	0.0292 (3)	0.0646 (4)	−0.0078 (3)	0.0262 (3)	−0.0142 (2)
S	0.0593 (7)	0.0333 (6)	0.0300 (5)	−0.0143 (6)	0.0240 (5)	−0.0042 (5)
C1	0.045 (3)	0.037 (2)	0.031 (2)	0.001 (2)	0.008 (2)	0.000 (2)
N1	0.037 (2)	0.036 (2)	0.031 (2)	0.001 (2)	0.0059 (17)	0.0040 (17)
O1	0.073 (2)	0.056 (2)	0.0359 (18)	−0.001 (2)	0.0100 (17)	0.0107 (18)
O2	0.060 (2)	0.0277 (16)	0.057 (2)	0.0082 (18)	0.0115 (19)	0.0035 (16)
N2	0.047 (2)	0.0326 (17)	0.0289 (18)	−0.010 (2)	0.0163 (17)	−0.0061 (16)
C2	0.046 (3)	0.026 (2)	0.044 (3)	−0.003 (2)	0.008 (2)	0.005 (2)
N3	0.045 (2)	0.0318 (18)	0.0267 (18)	−0.0118 (19)	0.0163 (17)	−0.0039 (15)
C3	0.034 (2)	0.0213 (18)	0.053 (3)	−0.005 (2)	0.017 (2)	−0.009 (2)
C4	0.039 (3)	0.031 (2)	0.028 (2)	−0.002 (2)	0.0086 (19)	−0.0053 (18)
N4	0.076 (3)	0.036 (2)	0.033 (2)	−0.023 (2)	0.028 (2)	−0.0124 (19)
C5	0.034 (2)	0.0246 (18)	0.035 (2)	−0.001 (2)	0.007 (2)	−0.0030 (19)
C6	0.034 (2)	0.0274 (19)	0.0261 (19)	−0.005 (2)	0.0140 (17)	−0.0026 (17)
C7	0.034 (2)	0.031 (2)	0.028 (2)	−0.004 (2)	0.0140 (19)	−0.0012 (18)
C8	0.035 (2)	0.027 (2)	0.031 (2)	−0.007 (2)	0.0109 (19)	−0.0013 (18)

Geometric parameters (Å, °)

Br—C3	1.887 (4)	C2—C3	1.362 (7)
S—C8	1.734 (4)	C2—H2B	0.9300
S—C7	1.744 (4)	N3—C8	1.297 (5)
C1—C2	1.371 (6)	C3—C4	1.386 (6)
C1—C6	1.379 (6)	C4—C5	1.361 (6)
C1—H1A	0.9300	C4—H4A	0.9300
N1—O2	1.210 (5)	N4—C8	1.353 (6)
N1—O1	1.215 (5)	N4—H4B	0.79 (6)
N1—C5	1.481 (6)	N4—H4C	0.81 (6)
N2—C7	1.303 (5)	C5—C6	1.399 (6)
N2—N3	1.392 (4)	C6—C7	1.462 (6)
C8—S—C7	86.4 (2)	C3—C4—H4A	121.0
C2—C1—C6	122.2 (4)	C8—N4—H4B	122 (4)
C2—C1—H1A	118.9	C8—N4—H4C	113 (4)
C6—C1—H1A	118.9	H4B—N4—H4C	119 (6)
O2—N1—O1	124.7 (4)	C4—C5—C6	123.3 (4)
O2—N1—C5	118.8 (4)	C4—C5—N1	116.2 (3)
O1—N1—C5	116.4 (4)	C6—C5—N1	120.4 (4)
C7—N2—N3	112.4 (3)	C1—C6—C5	115.9 (4)
C3—C2—C1	119.7 (4)	C1—C6—C7	120.7 (3)
C3—C2—H2B	120.2	C5—C6—C7	123.2 (4)
C1—C2—H2B	120.2	N2—C7—C6	124.3 (4)
C8—N3—N2	112.3 (3)	N2—C7—S	114.1 (3)
C2—C3—C4	120.8 (4)	C6—C7—S	121.6 (3)
C2—C3—Br	119.9 (3)	N3—C8—N4	123.8 (4)
C4—C3—Br	119.1 (3)	N3—C8—S	114.8 (3)
C5—C4—C3	118.0 (4)	N4—C8—S	121.3 (3)
C5—C4—H4A	121.0
C6—C1—C2—C3	−1.8 (8)	N1—C5—C6—C1	172.8 (4)
C7—N2—N3—C8	1.5 (5)	C4—C5—C6—C7	172.7 (5)
C1—C2—C3—C4	2.1 (8)	N1—C5—C6—C7	−11.3 (7)
C1—C2—C3—Br	178.4 (4)	N3—N2—C7—C6	−178.4 (4)
C2—C3—C4—C5	−2.8 (7)	N3—N2—C7—S	−1.3 (5)
Br—C3—C4—C5	−179.2 (4)	C1—C6—C7—N2	135.9 (5)
C3—C4—C5—C6	3.5 (8)	C5—C6—C7—N2	−39.8 (7)
C3—C4—C5—N1	−172.6 (4)	C1—C6—C7—S	−40.9 (6)
O2—N1—C5—C4	130.8 (5)	C5—C6—C7—S	143.4 (4)
O1—N1—C5—C4	−45.7 (6)	C8—S—C7—N2	0.7 (4)
O2—N1—C5—C6	−45.5 (6)	C8—S—C7—C6	177.8 (4)
O1—N1—C5—C6	138.1 (5)	N2—N3—C8—N4	177.6 (4)
C2—C1—C6—C5	2.3 (7)	N2—N3—C8—S	−1.0 (5)
C2—C1—C6—C7	−173.7 (5)	C7—S—C8—N3	0.2 (4)
C4—C5—C6—C1	−3.1 (7)	C7—S—C8—N4	−178.4 (4)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
N4—H4B···N3i	0.79 (7)	2.25 (7)	3.014 (6)	165 (7)
N4—H4C···N2ii	0.80 (6)	2.34 (6)	3.103 (6)	161 (6)

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