Perhydro­benzimidazole-2-thione

Abstract

The studied crystal of the title compound, C₇H₁₂N₂S, is a racemic mixture of two isomers, viz. S,S and R,R. The two isomers share the same position on a mirror plane in the space group P2₁/m; thus all atoms except one are disordered between two positions in a 1:1 ratio. Inter­molecular N—H⋯S hydrogen bonds link the mol­ecules into chains propagating in the [010] direction.

Related literature

For details of the synthesis, see: Allen et al. (1946 ▶). For useful applications of thio­urea derivetives, see: Schroeder (2006 ▶); Amos et al. (2007 ▶).

Experimental

Crystal data

• C₇H₁₂N₂S

• M _r = 156.25

• Monoclinic,

• a = 5.7459 (16) Å

• b = 8.543 (2) Å

• c = 8.816 (2) Å

• β = 98.208 (4)°

• V = 428.3 (2) ų

• Z = 2

• Mo Kα radiation

• μ = 0.31 mm⁻¹

• T = 293 (2) K

• 0.20 × 0.10 × 0.10 mm

Data collection

• Bruker SMART CCD area-detector diffractometer

• Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T _min = 0.931, T _max = 0.970

• 4541 measured reflections

• 934 independent reflections

• 740 reflections with I > 2σ(I)

• R _int = 0.019

Refinement

• R[F ² > 2σ(F ²)] = 0.047

• wR(F ²) = 0.154

• S = 1.03

• 934 reflections

• 91 parameters

• 6 restraints

• H-atom parameters constrained

• Δρ_max = 0.19 e Å⁻³

• Δρ_min = −0.14 e Å⁻³

Data collection: SMART (Bruker, 1997 ▶); cell refinement: SAINT (Bruker, 1999 ▶); data reduction: SAINT; 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: SHELXTL.

Supplementary Material

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
N1A—H1A⋯S1Ai	0.86	2.53	3.367 (11)	166
N1B—H1B⋯S1Bii	0.86	2.76	3.483 (11)	142

Symmetry codes: (i) ; (ii) .

supplementary crystallographic information

Comment

Thiourea and its derivatives are used in dyes, photographic film, elastomers, plastics, textiles, insecticides, preservatives, rodenticides and pharmaceuticals (Schroeder et al., 2006; Amos et al., 2007)

The title molecule consists of one thioimidazole five-membered ring and one six-membered ring which display chair conformation. The studied crystal is a racemic mixture of two isomers - (S,S) and (R,R), respectively - which share the same position on a mirror plane in space group P2₁/m, thus all atoms except one are disordered between two positions in a ratio 1:1. In the crystal, intermolecular N—H···S hydrogen bonds (Table 1) link the molecules into chains propagating in direction [010].

Experimental

The title compound was prepared according to the reported method (Allen et al.,1946). Crystals of (I) suitable for X-ray data collection were obtained by slow evaporation of a CH₂Cl₂ and MeOH solution in a ratio of 4:1 at 293 K.

Refinement

All H atoms were geometrically positioned (C–H 0.97-0.98 Å, N–H 0.86 Å) and refined as riding, with U_iso(H) = 1.2 U_eq(C, N). The crystal structure was refined in two space groups - P2₁ and P2₁/m, respectively. In both groups the severe disorder has been observed with almost identical values of final R-factors, so the preference has been made for P2₁/m.

Figures

Fig. 1.

View (S,S)-isomer of (I) showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.

Crystal data

C7H12N2S	F(000) = 168
Mr = 156.25	Dx = 1.211 Mg m−3
Monoclinic, P21/m	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yb	Cell parameters from 1728 reflections
a = 5.7459 (16) Å	θ = 2.3–24.6°
b = 8.543 (2) Å	µ = 0.31 mm−1
c = 8.816 (2) Å	T = 293 K
β = 98.208 (4)°	Block, colourless
V = 428.3 (2) Å3	0.20 × 0.10 × 0.10 mm
Z = 2

Data collection

Bruker SMART CCD area-detector diffractometer	934 independent reflections
Radiation source: fine-focus sealed tube	740 reflections with I > 2σ(I)
graphite	Rint = 0.019
φ and ω scans	θmax = 26.5°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −7→7
Tmin = 0.931, Tmax = 0.970	k = −9→10
4541 measured reflections	l = −11→11

Refinement

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)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.154	H-atom parameters constrained
S = 1.03	w = 1/[σ2(Fo2) + (0.1091P)2 + 0.0156P] where P = (Fo2 + 2Fc2)/3
934 reflections	(Δ/σ)max = 0.009
91 parameters	Δρmax = 0.19 e Å−3
6 restraints	Δρmin = −0.14 e Å−3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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 (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
C2	0.8296 (4)	0.2500	0.9716 (3)	0.0734 (7)
S1A	1.0495 (14)	0.2500	1.1194 (10)	0.0811 (15)	0.50
N1A	0.746 (3)	0.1176 (10)	0.9007 (16)	0.095 (4)	0.50
H1A	0.8101	0.0266	0.9121	0.113*	0.50
C3A	0.534 (2)	0.1541 (15)	0.8039 (15)	0.102 (4)	0.50
H3A	0.4166	0.1316	0.8715	0.122*	0.50
C4A	0.4237 (9)	0.0818 (6)	0.6596 (6)	0.0974 (14)	0.50
H4A1	0.3843	−0.0258	0.6803	0.117*	0.50
H4A2	0.5382	0.0796	0.5887	0.117*	0.50
C5A	0.2070 (17)	0.1621 (11)	0.5834 (11)	0.119 (6)	0.50
H5A1	0.0758	0.1270	0.6327	0.143*	0.50
H5A2	0.1779	0.1270	0.4777	0.143*	0.50
S1B	1.0773 (15)	0.2500	1.0974 (10)	0.088 (2)	0.50
N1B	0.697 (2)	0.3722 (7)	0.9103 (13)	0.0720 (19)	0.50
H1B	0.7108	0.4663	0.9453	0.086*	0.50
C3B	0.5339 (13)	0.3261 (13)	0.7810 (14)	0.0718 (18)	0.50
H3B	0.6275	0.3463	0.6985	0.086*	0.50
C4B	0.3201 (9)	0.4183 (6)	0.7250 (7)	0.0994 (15)	0.50
H4B1	0.3630	0.5236	0.6986	0.119*	0.50
H4B2	0.2188	0.4249	0.8039	0.119*	0.50
C5B	0.1951 (16)	0.3360 (13)	0.5860 (11)	0.121 (6)	0.50
H5B1	0.0328	0.3707	0.5709	0.146*	0.50
H5B2	0.2648	0.3707	0.4979	0.146*	0.50

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
C2	0.0817 (15)	0.0481 (12)	0.0918 (16)	0.000	0.0170 (12)	0.000
S1A	0.094 (2)	0.0635 (17)	0.0790 (14)	0.000	−0.010 (3)	0.000
N1A	0.079 (6)	0.063 (4)	0.136 (6)	0.015 (2)	−0.001 (4)	−0.013 (3)
C3A	0.141 (8)	0.044 (3)	0.118 (7)	−0.013 (3)	0.008 (5)	0.009 (4)
C4A	0.096 (3)	0.074 (3)	0.119 (4)	0.003 (3)	0.000 (3)	−0.018 (3)
C5A	0.112 (7)	0.091 (8)	0.134 (8)	−0.016 (5)	−0.050 (5)	−0.018 (6)
S1B	0.105 (2)	0.0474 (14)	0.114 (4)	0.000	0.0191 (14)	0.000
N1B	0.077 (5)	0.0334 (19)	0.102 (3)	−0.008 (2)	0.002 (3)	−0.002 (2)
C3B	0.063 (3)	0.052 (3)	0.096 (3)	0.006 (2)	−0.003 (2)	−0.014 (3)
C4B	0.096 (4)	0.070 (3)	0.130 (4)	0.022 (3)	0.009 (3)	0.010 (3)
C5B	0.098 (7)	0.122 (11)	0.148 (9)	−0.009 (5)	0.030 (5)	−0.011 (6)

Geometric parameters (Å, °)

C2—N1A	1.348 (6)	C5A—C5Ai	1.502 (19)
C2—N1Ai	1.348 (6)	C5A—H5A1	0.9700
C2—N1B	1.357 (5)	C5A—H5A2	0.9700
C2—N1Bi	1.357 (5)	N1B—C3B	1.426 (7)
C2—S1B	1.675 (5)	N1B—H1B	0.8600
C2—S1A	1.680 (4)	C3B—C3Bi	1.30 (2)
N1A—C3A	1.420 (8)	C3B—C4B	1.483 (7)
N1A—H1A	0.8600	C3B—H3B	0.9800
C3A—C4A	1.473 (8)	C4B—C5B	1.504 (7)
C3A—C3Ai	1.64 (3)	C4B—H4B1	0.9700
C3A—H3A	0.9800	C4B—H4B2	0.9700
C4A—C5A	1.494 (7)	C5B—C5Bi	1.47 (2)
C4A—H4A1	0.9700	C5B—H5B1	0.9700
C4A—H4A2	0.9700	C5B—H5B2	0.9700
N1A—C2—N1Ai	114.2 (10)	C4A—C5A—C5Ai	117.3 (4)
N1A—C2—N1B	108.6 (3)	C4A—C5A—H5A1	108.0
N1Ai—C2—N1Bi	108.6 (3)	C5Ai—C5A—H5A1	108.0
N1B—C2—N1Bi	100.6 (9)	C4A—C5A—H5A2	108.0
N1A—C2—S1B	121.3 (5)	C5Ai—C5A—H5A2	108.0
N1Ai—C2—S1B	121.3 (6)	H5A1—C5A—H5A2	107.2
N1B—C2—S1B	129.6 (4)	C2—N1B—C3B	111.9 (5)
N1Bi—C2—S1B	129.6 (4)	C2—N1B—H1B	124.0
N1A—C2—S1A	122.6 (5)	C3B—N1B—H1B	124.0
N1Ai—C2—S1A	122.6 (5)	C3Bi—C3B—N1B	106.0 (4)
N1B—C2—S1A	128.7 (4)	C3Bi—C3B—C4B	122.1 (5)
N1Bi—C2—S1A	128.7 (4)	N1B—C3B—C4B	122.6 (11)
C2—N1A—C3A	108.2 (8)	C3Bi—C3B—H3B	100.1
C2—N1A—H1A	125.9	N1B—C3B—H3B	100.1
C3A—N1A—H1A	125.9	C4B—C3B—H3B	100.1
N1A—C3A—C4A	130.7 (11)	C3B—C4B—C5B	107.4 (7)
N1A—C3A—C3Ai	102.7 (5)	C3B—C4B—H4B1	110.2
C4A—C3A—C3Ai	114.8 (6)	C5B—C4B—H4B1	110.2
N1A—C3A—H3A	101.3	C3B—C4B—H4B2	110.2
C4A—C3A—H3A	101.3	C5B—C4B—H4B2	110.2
C3Ai—C3A—H3A	101.3	H4B1—C4B—H4B2	108.5
C3A—C4A—C5A	115.0 (7)	C5Bi—C5B—C4B	117.9 (5)
C3A—C4A—H4A1	108.5	C5Bi—C5B—H5B1	107.8
C5A—C4A—H4A1	108.5	C4B—C5B—H5B1	107.8
C3A—C4A—H4A2	108.5	C5Bi—C5B—H5B2	107.8
C5A—C4A—H4A2	108.5	C4B—C5B—H5B2	107.8
H4A1—C4A—H4A2	107.5	H5B1—C5B—H5B2	107.2
N1Ai—C2—N1A—C3A	−21 (2)	N1A—C2—N1B—C3B	−6.9 (9)
N1B—C2—N1A—C3A	−7.6 (10)	N1Ai—C2—N1B—C3B	110 (5)
N1Bi—C2—N1A—C3A	47 (3)	N1Bi—C2—N1B—C3B	−18 (2)
S1B—C2—N1A—C3A	179.0 (10)	S1B—C2—N1B—C3B	165.7 (10)
S1A—C2—N1A—C3A	168.3 (11)	S1A—C2—N1B—C3B	177.5 (9)
C2—N1A—C3A—C4A	151.0 (13)	C2—N1B—C3B—C3Bi	11.8 (14)
C2—N1A—C3A—C3Ai	11.4 (13)	C2—N1B—C3B—C4B	159.0 (10)
N1A—C3A—C4A—C5A	−175.2 (15)	C3Bi—C3B—C4B—C5B	−39.2 (8)
C3Ai—C3A—C4A—C5A	−39.3 (9)	N1B—C3B—C4B—C5B	178.7 (11)
C3A—C4A—C5A—C5Ai	40.4 (9)	C3B—C4B—C5B—C5Bi	37.3 (8)

Symmetry codes: (i) x, −y+1/2, z.

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
N1A—H1A···S1Aii	0.86	2.53	3.367 (11)	166
N1B—H1B···S1Biii	0.86	2.76	3.483 (11)	142

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