A monoclinic polymorph of cysteamine hydro­chloride

Abstract

The title compound (systematic name: 2-mercaptoethan­aminium chloride), C₂H₈NS⁺·Cl⁻, the hydro­chloride salt of cysteamine, in contrast to the previously reported triclinic polymorph [Kim et al. (2002 ▶). Polyhedron, 21, 225–228], crystallized in the monoclinic crystal system. In the crystal, the cysteaminium cations are linked to the chloride anions via one S—H⋯Cl and three N—H⋯Cl hydrogen bonds. Two-dimensional slab-like networks are formed, which are stacked in [100]. This arrangement is similar to that observed in the triclinic polymorph.

Related literature

For the structure of the triclinic polymorph, see: Kim et al. (2002 ▶).

Experimental

Crystal data

• C₂H₈NS⁺·Cl⁻

• M _r = 113.60

• Monoclinic,

• a = 7.7441 (4) Å

• b = 8.4931 (5) Å

• c = 8.7126 (5) Å

• β = 101.962 (4)°

• V = 560.60 (5) ų

• Z = 4

• Mo Kα radiation

• μ = 0.90 mm⁻¹

• T = 173 K

• 0.40 × 0.40 × 0.40 mm

Data collection

• Stoe IPDS-2 diffractometer

• Absorption correction: numerical (X-SHAPE; Stoe & Cie, 2009 ▶) T _min = 0.738, T _max = 0.860

• 10581 measured reflections

• 1506 independent reflections

• 1426 reflections with I > 2σ(I)

• R _int = 0.072

Refinement

• R[F ² > 2σ(F ²)] = 0.032

• wR(F ²) = 0.088

• S = 1.10

• 1506 reflections

• 79 parameters

• All H-atom parameters refined

• Δρ_max = 0.30 e Å⁻³

• Δρ_min = −0.36 e Å⁻³

Data collection: X-AREA (Stoe & Cie, 2009 ▶); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2009 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 (Farrugia, 1997 ▶) and Mercury (Macrae et al., 2006 ▶); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 ▶).

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
S1—H1S⋯Cl1i	1.21 (3)	2.69 (3)	3.8003 (5)	152 (2)
N1—H1AN⋯Cl1ii	0.89 (3)	2.31 (3)	3.1485 (13)	159 (2)
N1—H1BN⋯Cl1iii	0.89 (2)	2.44 (2)	3.2563 (14)	152 (2)
N1—H1CN⋯Cl1	0.90 (3)	2.26 (3)	3.1437 (13)	169 (2)

Symmetry codes: (i) ; (ii) ; (iii) .

supplementary crystallographic information

Comment

The crystal structure of the triclinic polymorph, (I), of the title compound has been reported previously (Kim et al., 2002). Those crystals were prepared by recrystallization of cysteamine hydrochloride from hot alchohols, such as n-butanol, 2-propanol or n-propanol.

The stucture of the monoclinic polymorph, (II), is illustrated in Fig. 1, and the geometrical parameters are available in the Supplementary Information and the archived CIF. Here the crystalline sample received from the producers was used without further recrystallization. In contrast to (I), that crystallized with two independent molecules per asymmetric unit, polymorph (II) crystallized with one independent molecule per asymmetric unit. The conformation of the cation (i.e. torsion angle S—C—C—N) is similar in the two polymorphs: 61.49 (16)° in (II), and -60.28 and 60.65° in (I).

In the crystal of (II) the cysteaminium cations are linked to the chloride anions, via one S—H···Cl and three N—H···Cl hydrogen bonds (Table 1). Two-dimensional slab-like networks are formed, which stack in the [100] direction (Fig. 2). A similar hydrogen-bonded slab-like arrangement was also observed in the crystal structure of the triclinic polymorph (I), see Fig. 3.

Experimental

The sample used, supplied by Alfa Aesar (A Johnson Matthey Company) USA, consisted of colourless block-like crystals. A small piece of a large crystal was used for data collection.

Refinement

The H-atoms were all located in a difference electron-density map and were freely refined: S—H = 1.21 (3) Å; N—H = 0.89 (3)–0.90 (3) Å; C—H = 0.95 (2)–0.991 (17) Å.

Figures

Fig. 1.

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

Fig. 2.

A view, along the b axis, of the crystal packing of the title compound. The S—H···Cl and N—H···Cl hydrogen bonds are shown as dotted cyan lines (see Table 1 for details).

Fig. 3.

A view, along the a axis, of the crystal packing in the triclinic polymorph of the title compound (Kim et al., 2002). The S—H···Cl and N—H···Cl hydrogen bonds are shown as dotted cyan lines.

Crystal data

C2H8NS+·Cl−	F(000) = 240
Mr = 113.60	Dx = 1.346 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 15168 reflections
a = 7.7441 (4) Å	θ = 2.4–29.5°
b = 8.4931 (5) Å	µ = 0.90 mm−1
c = 8.7126 (5) Å	T = 173 K
β = 101.962 (4)°	Block, colourless
V = 560.60 (5) Å3	0.40 × 0.40 × 0.40 mm
Z = 4

Data collection

Stoe IPDS-2 diffractometer	1506 independent reflections
Radiation source: fine-focus sealed tube	1426 reflections with I > 2σ(I)
graphite	Rint = 0.072
φ and ω scans	θmax = 29.2°, θmin = 2.7°
Absorption correction: numerical (X-SHAPE; Stoe & Cie, 2009)	h = −10→10
Tmin = 0.738, Tmax = 0.860	k = −11→11
10581 measured reflections	l = −11→11

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)] = 0.032	All H-atom parameters refined
wR(F2) = 0.088	w = 1/[σ2(Fo2) + (0.0466P)2 + 0.1619P] where P = (Fo2 + 2Fc2)/3
S = 1.10	(Δ/σ)max = 0.001
1506 reflections	Δρmax = 0.30 e Å−3
79 parameters	Δρmin = −0.36 e Å−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.038 (9)

Special details

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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 (Ų)

	x	y	z	Uiso*/Ueq
S1	0.85152 (6)	0.67255 (4)	0.96395 (5)	0.0370 (1)
N1	0.83799 (17)	0.42811 (15)	0.67906 (15)	0.0288 (3)
C1	0.6807 (2)	0.53275 (19)	0.87903 (17)	0.0327 (4)
C2	0.67171 (19)	0.4989 (2)	0.70672 (17)	0.0326 (4)
Cl1	0.77972 (4)	0.40823 (4)	0.31160 (4)	0.0290 (1)
H1AN	0.853 (3)	0.335 (3)	0.726 (3)	0.045 (6)*
H1A	0.711 (3)	0.439 (3)	0.942 (3)	0.038 (5)*
H1B	0.570 (3)	0.572 (3)	0.894 (3)	0.045 (6)*
H1S	0.795 (3)	0.783 (3)	0.881 (3)	0.060 (7)*
H1BN	0.935 (3)	0.485 (3)	0.714 (3)	0.044 (6)*
H2A	0.652 (3)	0.597 (2)	0.644 (2)	0.033 (5)*
H2B	0.575 (3)	0.428 (3)	0.668 (3)	0.055 (7)*
H1CN	0.834 (3)	0.414 (3)	0.576 (3)	0.047 (6)*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
S1	0.0457 (3)	0.0318 (2)	0.0344 (2)	−0.0024 (1)	0.0107 (2)	−0.0034 (1)
N1	0.0285 (6)	0.0321 (6)	0.0256 (6)	−0.0013 (4)	0.0053 (4)	0.0005 (5)
C1	0.0301 (7)	0.0407 (8)	0.0284 (7)	0.0010 (6)	0.0083 (5)	0.0038 (6)
C2	0.0273 (6)	0.0432 (8)	0.0265 (6)	0.0019 (6)	0.0041 (5)	0.0032 (6)
Cl1	0.0289 (2)	0.0307 (2)	0.0268 (2)	0.0011 (1)	0.0046 (1)	−0.0016 (1)

Geometric parameters (Å, °)

S1—C1	1.8170 (16)	C1—C2	1.516 (2)
S1—H1S	1.21 (3)	C1—H1A	0.97 (3)
N1—C2	1.485 (2)	C1—H1B	0.95 (2)
N1—H1BN	0.89 (2)	C2—H2A	0.991 (17)
N1—H1AN	0.89 (3)	C2—H2B	0.97 (2)
N1—H1CN	0.90 (3)
C1—S1—H1S	96.9 (12)	S1—C1—H1B	108.4 (15)
H1AN—N1—H1CN	108 (2)	C2—C1—H1A	111.2 (15)
H1BN—N1—H1CN	105 (2)	C2—C1—H1B	110.1 (15)
C2—N1—H1AN	108.7 (16)	H1A—C1—H1B	109 (2)
C2—N1—H1BN	115.0 (16)	N1—C2—H2A	106.9 (13)
C2—N1—H1CN	111.4 (15)	N1—C2—H2B	109.1 (15)
H1AN—N1—H1BN	108 (2)	C1—C2—H2A	110.9 (10)
S1—C1—C2	114.04 (11)	C1—C2—H2B	109.7 (15)
N1—C2—C1	111.96 (12)	H2A—C2—H2B	108 (2)
S1—C1—H1A	103.7 (15)
S1—C1—C2—N1	61.49 (16)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
S1—H1S···Cl1i	1.21 (3)	2.69 (3)	3.8003 (5)	152 (2)
N1—H1AN···Cl1ii	0.89 (3)	2.31 (3)	3.1485 (13)	159 (2)
N1—H1BN···Cl1iii	0.89 (2)	2.44 (2)	3.2563 (14)	152 (2)
N1—H1CN···Cl1	0.90 (3)	2.26 (3)	3.1437 (13)	169 (2)

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