(S)-2-[(2-Ammonio­phenyl)­sulfanyl­methyl]pyrrolidinium dibromide

Li, B.; Zhang, S.; Wang, Y.; Luo, S.

doi:10.1107/S1600536808021089

organic compounds

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ISSN: 2056-9890

Volume 64| Part 8| August 2008| Page o1549

doi:10.1107/S1600536808021089

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(S)-2-[(2-Ammoniophenyl)sulfanylmethyl]pyrrolidinium dibromide

Bailin Li,^a,^b Shuai Zhang,^a Yifeng Wang ^a and Shuping Luo ^a ^*

^aState Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China, and ^bDepartment of Pharmaceutical and Chemical Engineering, Taizhou College, Linhai, Zhejiang 317000, People's Republic of China
^*Correspondence e-mail: bailinli1972@gmail.com

(Received 10 June 2008; accepted 8 July 2008; online 19 July 2008)

In the title compound, C₁₁H₁₈N₂S²⁺·2Br⁻, the pyrrolidine ring displays a half-chair conformation, with the flap C atom lying 0.522 (5) Å out of the plane of the other four atoms. The methylene C atom, which connects the pyrrolidinium ring and the thioether group, is displaced from the plane of four pyrrolidinium atoms by 0.690 (6) Å in the same direction as the flap C atom. The plane of four pyrrolidinium atoms is almost perpendicular to the benzene ring [dihedral angle = 75.02 (4)°]. The crystal structure is stabilized by hydrogen bonds between the N and Br atoms.

Related literature

The synthesis of (S)-(+)-2-bromomethylpyrrolidine hydrobromide was described by Xu et al. (2006 ). The development of asymmetric organocatalysis was reviewed by Seayad & List (2005 ).

Experimental

Crystal data

C₁₁H₁₈N₂S²⁺·2Br⁻
M_r = 370.15
Orthorhombic, P 2₁ 2₁ 2₁
a = 7.9399 (9) Å
b = 10.8427 (13) Å
c = 17.658 (2) Å
V = 1520.2 (3) Å³
Z = 4
Mo Kα radiation
μ = 5.45 mm⁻¹
T = 293 (2) K
0.49 × 0.42 × 0.36 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.103, T_max = 0.137
8969 measured reflections
3311 independent reflections
1808 reflections with I > 2σ(I)
R_int = 0.136

Refinement

R[F² > 2σ(F²)] = 0.058
wR(F²) = 0.134
S = 0.83
3311 reflections
158 parameters
3 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.67 e Å⁻³
Δρ_min = −0.50 e Å⁻³
Absolute structure: Flack (1983 ), 1394 Friedel pairs
Flack parameter: 0.00 (2)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2E⋯Br1ⁱ	0.83 (8)	2.39 (8)	3.201 (9)	169 (10)
N2—H2D⋯Br2ⁱⁱ	0.84 (6)	2.48 (4)	3.277 (9)	159 (8)
N2—H2C⋯Br1	0.84 (7)	2.47 (7)	3.298 (9)	173 (8)
N1—H1B⋯Br2	0.90	2.47	3.355 (7)	169
N1—H1A⋯Br2ⁱⁱ	0.90	2.33	3.224 (7)	170
Symmetry codes: (i) $[x-{\script{1\over 2}}, -y-{\script{1\over 2}}, -z]$ ; (ii) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z]$ .

Data collection: SMART (Bruker, 2001 ); cell refinement: SAINT-Plus (Bruker, 2000 ); data reduction: SAINT-Plus; 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.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808021089/pk2105sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808021089/pk2105Isup2.hkl

checkCIF report

Comment top

In recent years, the field of asymmetric organocatalysis has developed rapidly, attracting an increasing number of research groups around the world (Seayad & List, 2005). The title compound, readily synthesized from commercially available L-proline and 2-aminobenzenethiol, could act as an organocatalyst in the Michael addition of ketones to nitrostyrenes. The reaction gave the desired Michael adducts in good yields and high enantioselectivities. The structure of (S)-2-((2-ammoniophenylthio)methyl)pyrrolidinium dibromide is shown in Fig. 1.

The crystal is built of doubly protonated cations and bromide anions. The pyrrolidine ring displays a half-chair conformation, with the flap C atom lying 0.522 (5) Å from the remaining four atoms of the pyrrolidine which are almost coplanar. The methylene C atom, which connects the pyrrolidinium ring and the thioether group, is displaced from the plane of four pyrrolidinium atoms by 0.690 (6) Å in the same direction, as the flap C atom. The plane of four pyrrolidinium ring atoms is almost perpendicular to the benzene ring [dihedral angle 75.02 (4) °]. The crystal structure is stabilized by hydrogen-bonds between the N and Br atoms. The molecular packing of the title compound showing H-bridge interactions between cationic-anionic groups is shown in Fig. 2.

Related literature top

The synthesis of (S)-(+)-2-bromomethylpyrrolidine hydrobromide is described by Xu et al. (2006). The development of asymmetric organocatalysis is reviewed by Seayad & List (2005).

Experimental top

The title compound was synthesized by treating 2-aminobenzenethiol (1.25 g,10 mmol) with (S)-2-bromomethylpyrrolidine hydrobromide (2.47 g,10 mmol) in MeCN (30 ml) under stirring at 353 K for 24 h (yield 87%). The compound (S)-2-bromomethylpyrrolidine hydrobromide was obtained from commercially available L-proline by reduction with NaBH₄ and subsequent bromination with PBr₃ (Xu et al., 2006). Suitable crystals of the title compound were obtained by slow evaporation of an ethanol solution at room temperature.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); 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 (Sheldrick, 2008).

Figures top

	Fig. 1. The asymmetric unit of the title compound with the atomic labeling scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. The molecular packing of the title compound showing H-bridge interactions between cationic-anionic groups.

(S)-2-[(2-Ammoniophenyl)sulfanylmethyl]pyrrolidinium dibromide top

Crystal data top

C₁₁H₁₈N₂S²⁺·2Br⁻	F(000) = 736
M_r = 370.15	D_x = 1.617 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 1525 reflections
a = 7.9399 (9) Å	θ = 4.4–38.3°
b = 10.8427 (13) Å	µ = 5.45 mm⁻¹
c = 17.658 (2) Å	T = 293 K
V = 1520.2 (3) Å³	Prismatic, colorless
Z = 4	0.49 × 0.42 × 0.37 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	3311 independent reflections
Radiation source: fine-focus sealed tube	1808 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.136
ϕ and ω scans	θ_max = 27.0°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −9→10
T_min = 0.103, T_max = 0.137	k = −13→12
8969 measured reflections	l = −22→18

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F² > 2σ(F²)] = 0.058	w = 1/[σ²(F_o²) + (0.049P)²] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.134	(Δ/σ)_max < 0.001
S = 0.83	Δρ_max = 0.67 e Å⁻³
3311 reflections	Δρ_min = −0.50 e Å⁻³
158 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
3 restraints	Extinction coefficient: 0.0005 (1)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 1394 Friedel pairs
Secondary atom site location: difference Fourier map	Absolute structure parameter: 0.00 (2)

Crystal data top

C₁₁H₁₈N₂S²⁺·2Br⁻	V = 1520.2 (3) Å³
M_r = 370.15	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 7.9399 (9) Å	µ = 5.45 mm⁻¹
b = 10.8427 (13) Å	T = 293 K
c = 17.658 (2) Å	0.49 × 0.42 × 0.37 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	3311 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	1808 reflections with I > 2σ(I)
T_min = 0.103, T_max = 0.137	R_int = 0.136
8969 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.058	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.134	Δρ_max = 0.67 e Å⁻³
S = 0.83	Δρ_min = −0.50 e Å⁻³
3311 reflections	Absolute structure: Flack (1983), 1394 Friedel pairs
158 parameters	Absolute structure parameter: 0.00 (2)
3 restraints

Special details top

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 > 2σ(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	0.30470 (12)	−0.24305 (9)	−0.08797 (5)	0.0559 (3)
Br2	−0.38177 (12)	0.34415 (8)	0.06967 (5)	0.0526 (3)
S1	−0.0443 (3)	0.1034 (2)	0.14946 (13)	0.0524 (6)
N1	0.0399 (9)	0.3571 (6)	0.0600 (4)	0.0502 (18)
H1A	0.0636	0.2939	0.0288	0.060*
H1B	−0.0728	0.3650	0.0630	0.060*
N2	0.1147 (12)	−0.0815 (8)	0.0452 (5)	0.0487 (18)
C1	0.1159 (18)	0.4726 (9)	0.0308 (7)	0.083 (3)
H1C	0.0296	0.5273	0.0111	0.100*
H1D	0.1959	0.4549	−0.0093	0.100*
C2	0.2025 (14)	0.5297 (9)	0.0973 (7)	0.072 (3)
H2A	0.3237	0.5225	0.0921	0.087*
H2B	0.1735	0.6164	0.1013	0.087*
C3	0.1443 (14)	0.4625 (9)	0.1640 (6)	0.068 (3)
H3A	0.0420	0.4990	0.1840	0.081*
H3B	0.2297	0.4627	0.2033	0.081*
C4	0.1120 (12)	0.3339 (8)	0.1362 (4)	0.049 (2)
H4	0.2194	0.2901	0.1309	0.059*
C5	−0.0079 (11)	0.2577 (8)	0.1852 (4)	0.052 (2)
H5A	−0.1150	0.3004	0.1885	0.062*
H5B	0.0381	0.2519	0.2359	0.062*
C6	0.1553 (11)	0.0316 (8)	0.1640 (5)	0.047 (2)
C7	0.2504 (11)	0.0537 (9)	0.2270 (5)	0.056 (3)
H7	0.2117	0.1092	0.2632	0.068*
C8	0.4032 (13)	−0.0049 (10)	0.2382 (6)	0.073 (3)
H8	0.4680	0.0138	0.2805	0.087*
C9	0.4579 (14)	−0.0887 (10)	0.1879 (6)	0.071 (3)
H9	0.5602	−0.1285	0.1956	0.085*
C10	0.3611 (11)	−0.1161 (8)	0.1239 (5)	0.053 (2)
H10	0.3980	−0.1750	0.0893	0.063*
C11	0.2112 (12)	−0.0555 (8)	0.1123 (5)	0.045 (2)
H2C	0.157 (10)	−0.127 (6)	0.012 (4)	0.06 (3)*
H2D	0.094 (12)	−0.032 (6)	0.010 (3)	0.06 (3)*
H2E	0.043 (10)	−0.135 (7)	0.054 (6)	0.09 (4)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0514 (6)	0.0627 (5)	0.0536 (6)	0.0081 (5)	−0.0055 (4)	−0.0024 (5)
Br2	0.0526 (6)	0.0614 (5)	0.0438 (5)	0.0072 (5)	−0.0041 (4)	−0.0022 (5)
S1	0.0412 (14)	0.0682 (15)	0.0479 (14)	0.0052 (12)	0.0015 (11)	0.0049 (12)
N1	0.045 (4)	0.060 (4)	0.046 (4)	0.007 (4)	0.004 (3)	−0.001 (4)
N2	0.054 (5)	0.048 (5)	0.044 (5)	−0.003 (5)	0.002 (5)	−0.002 (4)
C1	0.105 (10)	0.061 (7)	0.084 (8)	0.010 (7)	0.005 (8)	0.006 (6)
C2	0.055 (7)	0.055 (6)	0.107 (10)	0.005 (5)	0.010 (7)	−0.017 (6)
C3	0.062 (8)	0.074 (7)	0.067 (7)	−0.006 (6)	−0.007 (6)	−0.021 (6)
C4	0.038 (5)	0.066 (6)	0.044 (5)	0.015 (5)	0.000 (4)	0.003 (5)
C5	0.053 (6)	0.070 (6)	0.033 (4)	0.019 (6)	0.002 (4)	−0.009 (5)
C6	0.033 (6)	0.062 (6)	0.046 (5)	0.008 (4)	−0.006 (4)	0.010 (4)
C7	0.043 (6)	0.077 (7)	0.048 (6)	0.012 (5)	0.003 (5)	0.000 (5)
C8	0.062 (8)	0.102 (8)	0.055 (7)	0.010 (7)	−0.022 (6)	−0.008 (6)
C9	0.054 (7)	0.103 (8)	0.056 (7)	0.028 (7)	−0.005 (6)	−0.001 (6)
C10	0.046 (6)	0.061 (6)	0.051 (5)	0.022 (5)	0.011 (5)	0.010 (4)
C11	0.044 (6)	0.059 (6)	0.031 (5)	0.000 (5)	0.000 (4)	0.007 (4)

Geometric parameters (Å, º) top

Br1—H2C	2.47 (7)	C3—C4	1.500 (12)
Br2—H1B	2.4665	C3—H3A	0.9700
S1—C6	1.784 (8)	C3—H3B	0.9700
S1—C5	1.811 (9)	C4—C5	1.529 (12)
N1—C1	1.483 (12)	C4—H4	0.9800
N1—C4	1.484 (10)	C5—H5A	0.9700
N1—H1A	0.9000	C5—H5B	0.9700
N1—H1B	0.9000	C6—C7	1.366 (11)
N2—C11	1.438 (11)	C6—C11	1.388 (11)
N2—H2C	0.84 (7)	C7—C8	1.383 (13)
N2—H2D	0.84 (6)	C7—H7	0.9300
N2—H2E	0.83 (8)	C8—C9	1.343 (13)
C1—C2	1.495 (14)	C8—H8	0.9300
C1—H1C	0.9700	C9—C10	1.399 (13)
C1—H1D	0.9700	C9—H9	0.9300
C2—C3	1.460 (13)	C10—C11	1.374 (12)
C2—H2A	0.9700	C10—H10	0.9300
C2—H2B	0.9700

C6—S1—C5	102.2 (4)	N1—C4—C3	101.8 (7)
C1—N1—C4	107.5 (8)	N1—C4—C5	111.3 (7)
C1—N1—H1A	110.2	C3—C4—C5	115.1 (8)
C4—N1—H1A	110.2	N1—C4—H4	109.4
C1—N1—H1B	110.2	C3—C4—H4	109.4
C4—N1—H1B	110.2	C5—C4—H4	109.4
H1A—N1—H1B	108.5	C4—C5—S1	113.7 (6)
C11—N2—H2C	118 (6)	C4—C5—H5A	108.8
C11—N2—H2D	126 (6)	S1—C5—H5A	108.8
H2C—N2—H2D	87 (7)	C4—C5—H5B	108.8
C11—N2—H2E	111 (7)	S1—C5—H5B	108.8
H2C—N2—H2E	90 (9)	H5A—C5—H5B	107.7
H2D—N2—H2E	117 (10)	C7—C6—C11	118.6 (8)
N1—C1—C2	105.3 (9)	C7—C6—S1	122.1 (7)
N1—C1—H1C	110.7	C11—C6—S1	119.1 (7)
C2—C1—H1C	110.7	C6—C7—C8	121.3 (9)
N1—C1—H1D	110.7	C6—C7—H7	119.3
C2—C1—H1D	110.7	C8—C7—H7	119.3
H1C—C1—H1D	108.8	C9—C8—C7	120.0 (10)
C3—C2—C1	106.3 (8)	C9—C8—H8	120.0
C3—C2—H2A	110.5	C7—C8—H8	120.0
C1—C2—H2A	110.5	C8—C9—C10	120.1 (9)
C3—C2—H2B	110.5	C8—C9—H9	120.0
C1—C2—H2B	110.5	C10—C9—H9	120.0
H2A—C2—H2B	108.7	C11—C10—C9	119.6 (9)
C2—C3—C4	104.7 (7)	C11—C10—H10	120.2
C2—C3—H3A	110.8	C9—C10—H10	120.2
C4—C3—H3A	110.8	C10—C11—C6	120.3 (8)
C2—C3—H3B	110.8	C10—C11—N2	119.4 (8)
C4—C3—H3B	110.8	C6—C11—N2	120.3 (8)
H3A—C3—H3B	108.9

C4—N1—C1—C2	−12.2 (11)	C11—C6—C7—C8	2.8 (14)
N1—C1—C2—C3	−12.1 (11)	S1—C6—C7—C8	178.6 (8)
C1—C2—C3—C4	31.4 (11)	C6—C7—C8—C9	−2.4 (15)
C1—N1—C4—C3	30.7 (10)	C7—C8—C9—C10	0.5 (16)
C1—N1—C4—C5	153.8 (8)	C8—C9—C10—C11	1.0 (15)
C2—C3—C4—N1	−38.0 (10)	C9—C10—C11—C6	−0.6 (13)
C2—C3—C4—C5	−158.6 (8)	C9—C10—C11—N2	178.2 (9)
N1—C4—C5—S1	64.5 (8)	C7—C6—C11—C10	−1.3 (12)
C3—C4—C5—S1	179.7 (7)	S1—C6—C11—C10	−177.2 (6)
C6—S1—C5—C4	69.0 (6)	C7—C6—C11—N2	180.0 (8)
C5—S1—C6—C7	38.7 (8)	S1—C6—C11—N2	4.1 (11)
C5—S1—C6—C11	−145.6 (7)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2E···Br1ⁱ	0.83 (8)	2.39 (8)	3.201 (9)	169 (10)
N2—H2D···Br2ⁱⁱ	0.84 (6)	2.48 (4)	3.277 (9)	159 (8)
N2—H2C···Br1	0.84 (7)	2.47 (7)	3.298 (9)	173 (8)
N1—H1B···Br2	0.90	2.47	3.355 (7)	169
N1—H1A···Br2ⁱⁱ	0.90	2.33	3.224 (7)	170

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

Experimental details

Crystal data
Chemical formula	C₁₁H₁₈N₂S²⁺·2Br⁻
M_r	370.15
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	293
a, b, c (Å)	7.9399 (9), 10.8427 (13), 17.658 (2)
V (Å³)	1520.2 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	5.45
Crystal size (mm)	0.49 × 0.42 × 0.37

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.103, 0.137
No. of measured, independent and observed [I > 2σ(I)] reflections	8969, 3311, 1808
R_int	0.136
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.058, 0.134, 0.83
No. of reflections	3311
No. of parameters	158
No. of restraints	3
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.67, −0.50
Absolute structure	Flack (1983), 1394 Friedel pairs
Absolute structure parameter	0.00 (2)

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2E···Br1ⁱ	0.83 (8)	2.39 (8)	3.201 (9)	169 (10)
N2—H2D···Br2ⁱⁱ	0.84 (6)	2.48 (4)	3.277 (9)	159 (8)
N2—H2C···Br1	0.84 (7)	2.47 (7)	3.298 (9)	173 (8)
N1—H1B···Br2	0.90	2.47	3.355 (7)	169.3
N1—H1A···Br2ⁱⁱ	0.90	2.33	3.224 (7)	169.6

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

References

Bruker (2000). SAINT-Plus. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Bruker (2001). SMART. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
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Volume 64| Part 8| August 2008| Page o1549

doi:10.1107/S1600536808021089

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