2-(1,3-Benzothia­zol-2-yl)guanidinium chloride

Abstract

The non-H atoms of the cation of the title salt, C₈H₉N₄S⁺·Cl⁻, are approximately co-planar (r.m.s. deviation = 0.037 Å), with one amino group forming an intra­molecular hydrogen bond to the tertiary N atom of the benzothia­zole fused-ring system. The cations and anions are linked by cyclic R ₂ ¹(6) N—H⋯Cl hydrogen-bonding associations, generating helical chains running along the b-axis direction.

Related literature

For the synthesis, see: Takahashi & Niino (1943 ▶). For the structure of 2-(1,3-benzothia­zol-2-yl)guanidine, see: Mohamed et al. (2011 ▶). For graph-set analysis, see: Etter et al. (1990 ▶).

Experimental

Crystal data

• C₈H₉N₄S⁺·Cl⁻

• M _r = 228.71

• Orthorhombic,

• a = 3.8857 (5) Å

• b = 11.0349 (17) Å

• c = 22.186 (3) Å

• V = 951.3 (2) ų

• Z = 4

• Mo Kα radiation

• μ = 0.58 mm⁻¹

• T = 120 K

• 0.12 × 0.03 × 0.01 mm

Data collection

• Rigaku Saturn 724+ diffractometer

• Absorption correction: multi-scan (CrystalClear; Rigaku, 2011 ▶) T _min = 0.933, T _max = 0.994

• 14016 measured reflections

• 2146 independent reflections

• 2117 reflections with I > 2σ(I)

• R _int = 0.034

Refinement

• R[F ² > 2σ(F ²)] = 0.030

• wR(F ²) = 0.076

• S = 1.07

• 2146 reflections

• 147 parameters

• 5 restraints

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

• Δρ_max = 0.26 e Å⁻³

• Δρ_min = −0.27 e Å⁻³

• Absolute structure: Flack (1983 ▶), 839 Friedel pairs

• Flack parameter: −0.01 (7)

Data collection: CrystalClear (Rigaku, 2011 ▶); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: X-SEED (Barbour, 2001 ▶); software used to prepare material for publication: publCIF (Westrip, 2010 ▶).

Supplementary Material

Supplementary material file. DOI: 10.1107/S1600536811044643/zs2157Isup3.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
N2—H1⋯Cl1i	0.88 (1)	2.21 (1)	3.074 (2)	165 (2)
N3—H2⋯Cl1	0.88 (1)	2.62 (2)	3.380 (2)	146 (2)
N4—H3⋯Cl1	0.88 (1)	2.31 (1)	3.157 (2)	160 (2)
N4—H4⋯N1	0.88 (1)	2.06 (2)	2.713 (2)	131 (2)

Symmetry code: (i) .

supplementary crystallographic information

Comment

A recent study (Mohamed et al., 2011) describes the crystal structure of 2-(1,3-benzothiazol-2-yl)guanidine, which was synthesized by the reaction of 2-aminothiophenol and cyanoguanidine in 10% sulfuric acid medium. The product of the reaction is probably a sulfate or bisulfate salt that is then converted to the neutral compound upon treatment with sodium hydroxide. In the present study, 2-(1,3-benzothioazol-2-yl)guanidine is converted to the hydrochloride salt by treatment with hydrochloric acid. The non-H atoms of the cation of the title salt, C₈H₉N₄S⁺ Cl^- (Scheme I), lie on a plane (r.m.s. deviation 0.037 Å), with one amino group forming an intramolecular hydrogen bond to the tertiary N atom of the benzothiazole fused-ring (Fig. 1). The cations and anions are linked by cyclic N—H···Cl hydrogen-bonding associations [graph set R¹₂(6) (Etter et al., 1990)] (Table 1), to generate helical chains running along the b-axis of the orthorhombic unit cell. This salt was first reported in 1943 (Takahashi & Niino, 1943).

Experimental

2-(1,3-Benzothiazol-2-yl)guanidine (0.05 mol) was heated in ethanol (50 ml) in the presence of a few drops of hydrochloric acid for 3 h. The mixture was cooled and the product was collected and recrystallized from ethanol to give the title compound (m.p. 523 K) in 95% yield; .

Refinement

Carbon-bound H-atoms were placed in calculated positions (C—H = 0.95 Å) and were included in the refinement in the riding model approximation, with U_iso(H) set to 1.2U_eq(C). The amino H-atoms were located in a difference Fourier map, and were refined with a distance restraint of N—H = 0.88±0.01 Å with their isotropic displacement parameters freely refining.

Figures

Fig. 1.

Thermal ellipsoid plot (Barbour, 2001) of C8H9N4S+ Cl- at the 70% probability level. Hydrogen atoms are drawn as spheres of arbitrary radius.

Crystal data

C8H9N4S+·Cl−	Dx = 1.597 Mg m−3
Mr = 228.71	Melting point: 523 K
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 3321 reflections
a = 3.8857 (5) Å	θ = 2.1–31.0°
b = 11.0349 (17) Å	µ = 0.58 mm−1
c = 22.186 (3) Å	T = 120 K
V = 951.3 (2) Å3	Lath, colorless
Z = 4	0.12 × 0.03 × 0.01 mm
F(000) = 472

Data collection

Rigaku Saturn 724+ diffractometer	2146 independent reflections
Radiation source: rotating anode	2117 reflections with I > 2σ(I)
confocal	Rint = 0.034
Detector resolution: 28.5714 pixels mm-1	θmax = 27.5°, θmin = 2.1°
ω scans	h = −4→4
Absorption correction: multi-scan (CrystalClear; Rigaku, 2011)	k = −14→14
Tmin = 0.933, Tmax = 0.994	l = −28→28
14016 measured reflections

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)] = 0.030	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.076	w = 1/[σ2(Fo2) + (0.0454P)2 + 0.3169P] where P = (Fo2 + 2Fc2)/3
S = 1.07	(Δ/σ)max = 0.001
2146 reflections	Δρmax = 0.26 e Å−3
147 parameters	Δρmin = −0.27 e Å−3
5 restraints	Absolute structure: Flack (1983), 839 Friedel pairs
Primary atom site location: structure-invariant direct methods	Flack parameter: −0.01 (7)

Special details

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.

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

	x	y	z	Uiso*/Ueq
Cl1	0.94400 (14)	0.19472 (4)	0.72036 (2)	0.02120 (13)
S1	0.32449 (13)	0.63436 (4)	0.96176 (2)	0.01619 (12)
N1	0.6155 (4)	0.42234 (14)	0.95141 (7)	0.0168 (4)
N2	0.4500 (5)	0.51363 (15)	0.85919 (7)	0.0175 (4)
H1	0.344 (7)	0.5752 (17)	0.8420 (12)	0.032 (7)*
N3	0.4832 (5)	0.43982 (16)	0.76315 (7)	0.0209 (4)
H2	0.539 (7)	0.3806 (17)	0.7388 (10)	0.027 (7)*
H5	0.390 (8)	0.5097 (17)	0.7530 (14)	0.053 (10)*
N4	0.7193 (5)	0.32801 (15)	0.83996 (8)	0.0211 (4)
H3	0.792 (7)	0.2752 (18)	0.8130 (9)	0.029 (7)*
H4	0.766 (7)	0.320 (2)	0.8786 (5)	0.023 (6)*
C1	0.4490 (5)	0.55994 (17)	1.02742 (9)	0.0168 (4)
C2	0.4162 (5)	0.59888 (18)	1.08674 (9)	0.0179 (4)
H2A	0.3142	0.6748	1.0962	0.021*
C3	0.5382 (5)	0.52252 (18)	1.13174 (9)	0.0195 (4)
H3A	0.5207	0.5467	1.1727	0.023*
C4	0.6856 (6)	0.41107 (18)	1.11753 (9)	0.0188 (4)
H4A	0.7657	0.3602	1.1491	0.023*
C5	0.7178 (6)	0.37284 (18)	1.05846 (9)	0.0186 (4)
H5A	0.8187	0.2967	1.0492	0.022*
C6	0.5993 (5)	0.44847 (17)	1.01311 (9)	0.0160 (4)
C7	0.4809 (5)	0.51068 (17)	0.92100 (9)	0.0158 (4)
C8	0.5560 (6)	0.42508 (17)	0.82086 (8)	0.0162 (4)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Cl1	0.0242 (3)	0.0190 (2)	0.0205 (2)	−0.0008 (2)	−0.00028 (19)	−0.00403 (19)
S1	0.0198 (2)	0.0132 (2)	0.0156 (2)	0.00165 (17)	−0.0007 (2)	0.00035 (18)
N1	0.0209 (9)	0.0139 (7)	0.0155 (8)	−0.0013 (6)	−0.0004 (7)	−0.0005 (6)
N2	0.0254 (9)	0.0127 (7)	0.0144 (8)	0.0006 (7)	−0.0006 (7)	0.0001 (6)
N3	0.0310 (10)	0.0157 (8)	0.0159 (8)	−0.0017 (8)	−0.0003 (8)	−0.0036 (7)
N4	0.0290 (10)	0.0167 (8)	0.0174 (8)	0.0022 (8)	0.0016 (8)	−0.0009 (7)
C1	0.0172 (9)	0.0141 (8)	0.0191 (9)	−0.0010 (8)	−0.0012 (8)	0.0029 (7)
C2	0.0183 (10)	0.0164 (9)	0.0189 (9)	−0.0014 (8)	0.0021 (8)	−0.0008 (7)
C3	0.0190 (10)	0.0228 (10)	0.0167 (9)	−0.0059 (9)	0.0013 (8)	0.0004 (8)
C4	0.0181 (9)	0.0204 (9)	0.0178 (9)	−0.0017 (9)	−0.0013 (8)	0.0053 (7)
C5	0.0205 (10)	0.0155 (9)	0.0199 (9)	0.0007 (8)	0.0004 (8)	0.0007 (7)
C6	0.0158 (10)	0.0154 (9)	0.0169 (9)	−0.0022 (7)	0.0009 (7)	0.0000 (7)
C7	0.0161 (10)	0.0134 (8)	0.0179 (9)	−0.0015 (7)	0.0011 (8)	0.0006 (7)
C8	0.0191 (9)	0.0142 (8)	0.0154 (9)	−0.0024 (8)	0.0033 (8)	0.0008 (7)

Geometric parameters (Å, °)

S1—C1	1.7409 (19)	N4—H4	0.882 (10)
S1—C7	1.746 (2)	C1—C2	1.390 (3)
N1—C7	1.296 (2)	C1—C6	1.398 (3)
N1—C6	1.400 (2)	C2—C3	1.390 (3)
N2—C8	1.359 (2)	C2—H2A	0.9500
N2—C7	1.377 (2)	C3—C4	1.393 (3)
N2—H1	0.882 (10)	C3—H3A	0.9500
N3—C8	1.321 (3)	C4—C5	1.382 (3)
N3—H2	0.876 (10)	C4—H4A	0.9500
N3—H5	0.880 (10)	C5—C6	1.386 (3)
N4—C8	1.315 (3)	C5—H5A	0.9500
N4—H3	0.883 (10)
C1—S1—C7	88.16 (9)	C2—C3—H3A	119.6
C7—N1—C6	109.63 (17)	C4—C3—H3A	119.6
C8—N2—C7	125.43 (17)	C5—C4—C3	121.41 (19)
C8—N2—H1	115.2 (19)	C5—C4—H4A	119.3
C7—N2—H1	119.3 (19)	C3—C4—H4A	119.3
C8—N3—H2	116.9 (18)	C4—C5—C6	118.31 (19)
C8—N3—H5	116 (2)	C4—C5—H5A	120.8
H2—N3—H5	127 (3)	C6—C5—H5A	120.8
C8—N4—H3	118.3 (16)	C5—C6—C1	120.25 (18)
C8—N4—H4	119.6 (16)	C5—C6—N1	124.80 (18)
H3—N4—H4	122 (2)	C1—C6—N1	114.95 (17)
C2—C1—C6	121.68 (18)	N1—C7—N2	124.85 (18)
C2—C1—S1	128.38 (15)	N1—C7—S1	117.31 (15)
C6—C1—S1	109.95 (14)	N2—C7—S1	117.84 (14)
C3—C2—C1	117.47 (18)	N4—C8—N3	121.06 (18)
C3—C2—H2A	121.3	N4—C8—N2	122.02 (18)
C1—C2—H2A	121.3	N3—C8—N2	116.92 (18)
C2—C3—C4	120.87 (19)
C7—S1—C1—C2	179.9 (2)	S1—C1—C6—N1	−0.1 (2)
C7—S1—C1—C6	0.28 (16)	C7—N1—C6—C5	179.4 (2)
C6—C1—C2—C3	−0.1 (3)	C7—N1—C6—C1	−0.3 (2)
S1—C1—C2—C3	−179.68 (17)	C6—N1—C7—N2	−178.94 (19)
C1—C2—C3—C4	−0.3 (3)	C6—N1—C7—S1	0.5 (2)
C2—C3—C4—C5	0.4 (3)	C8—N2—C7—N1	−0.2 (3)
C3—C4—C5—C6	0.0 (3)	C8—N2—C7—S1	−179.64 (17)
C4—C5—C6—C1	−0.5 (3)	C1—S1—C7—N1	−0.50 (16)
C4—C5—C6—N1	179.77 (19)	C1—S1—C7—N2	179.02 (17)
C2—C1—C6—C5	0.6 (3)	C7—N2—C8—N4	−3.7 (3)
S1—C1—C6—C5	−179.81 (16)	C7—N2—C8—N3	175.3 (2)
C2—C1—C6—N1	−179.68 (18)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H1···Cl1i	0.88 (1)	2.21 (1)	3.074 (2)	165 (2)
N3—H2···Cl1	0.88 (1)	2.62 (2)	3.380 (2)	146 (2)
N4—H3···Cl1	0.88 (1)	2.31 (1)	3.157 (2)	160 (2)
N4—H4···N1	0.88 (1)	2.06 (2)	2.713 (2)	131 (2)

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