(7aS)-(–)-Dimeth­yl(1-oxido-3-oxo-5,6,7,7a-tetra­hydro-3H-pyrrolizin-2-yl)sulfonium

Abstract

In the zwitterionic title compound, C₉H₁₃NO₂S, the pyrrolidine heterocycle adopts an envelope conformation (with the C atom in the 7-position as the flap). The negative charge is delocalized over the two carbonyl groups and the C atom connecting them. The positive charge is located on the S atom. Two inter­molecular C—H⋯O inter­actions are observed. The molecular geometry at the S atom is trigonal pyramidal.

Related literature  

For background to the synthesis of chiral non-racemic zwitterionic compounds, see: Zang et al. (2008 ▶); Kappe et al. (1983 ▶); Palillero et al. (2009 ▶). For the biological activity of related structures, see: Basco et al. (1994 ▶); Koruznjak et al. (2003 ▶). For puckering parameters, see: Cremer & Pople (1975 ▶).

Experimental  

Crystal data  

• C₉H₁₃NO₂S

• M _r = 199.26

• Orthorhombic,

• a = 5.8761 (3) Å

• b = 9.0858 (5) Å

• c = 17.7107 (9) Å

• V = 945.56 (9) ų

• Z = 4

• Mo Kα radiation

• μ = 0.31 mm⁻¹

• T = 130 K

• 0.46 × 0.33 × 0.07 mm

Data collection  

• Oxford Xcalibur Atlas Gemini diffractometer

• Absorption correction: analytical (CrysAlis PRO; Oxford Diffraction, 2009 ▶) T _min = 0.895, T _max = 0.976

• 6356 measured reflections

• 1873 independent reflections

• 1736 reflections with I > 2σ(I)

• R _int = 0.037

Refinement  

• R[F ² > 2σ(F ²)] = 0.027

• wR(F ²) = 0.065

• S = 1.04

• 1873 reflections

• 120 parameters

• H-atom parameters constrained

• Δρ_max = 0.20 e Å⁻³

• Δρ_min = −0.26 e Å⁻³

• Absolute structure: Flack (1983 ▶), with 758 Friedel pairs

• Flack parameter: −0.07 (7)

Data collection: CrysAlis PRO (Oxford Diffraction, 2009 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis RED (Oxford Diffraction, 2002 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Supplementary Material

Supplementary material file. DOI: 10.1107/S1600536812003601/bt5793Isup3.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
C4—H4⋯O2i	1.00	2.55	3.4145 (19)	145
C7—H7B⋯O1ii	0.99	2.59	3.570 (2)	173

Symmetry codes: (i) ; (ii) .

supplementary crystallographic information

Comment

The synthesis of chiral non racemic zwitterionic compounds is an original area of interest in organic chemistry (Zang et al., 2008; Kappe et al., 1983) because they are useful intermediates for the synthesis of diverse interesting nitrogen heterocyclic compounds (Palillero et al., 2009) with interesting biological properties (Basco et al., 1994; Koruznjak et al., 2003).

In the title zwitterionic compound, C₁₉H₁₃NO₂S, the chiral centre shows an S configuration, and the five membered pyrrolidine heterocycle shows an envelope conformations on C5 with puckering parameters (Cremer & Pople, 1975) φ₂ = 258.4 (3)° and q₂ = 0.4038 (19) Å. The five membered ring N1/C1/C2/C3/C4 shows a twist conformation on N1—C1 with puckering parameters φ₂ = 0.0903 (18)° and q₂ = 22.4 (12) Å. The bond distances of C1—O2 [1.235 (2) Å] and C3—O1 [1.238 (2) Å] are similar as in related systems which were previously reported. The C2—C3 bond distance [1.406 (2) Å] has the same length as an aromatic bond and C2—C1 [1.435 (2) Å] is shorter than a typical sp³—sp³ bond distance. This suggests, that the negative charge is delocalized on the O1/C3/C2/C2/O2 system. Two intermolecular weak interactions C4—H4···O2 (3.412 (2) Å) and C7—H7B···O1 (3.570 (2) Å) are observed.

Experimental

The title compound, was obtained by an intramolecular cyclization reaction of (S)-(-)-[2-(2-Methoxycarbonyl-pyrrolidin-1-yl)-2-oxo-ethyl]-dimethyl-sulfonium; bromide (1 mmol), which was dissolved in CH₃CN (10 ml), treated with KOH (1.2 mmol) and stirred for 2 h at room temperature. The resulting mixture was concentrated in vacuum and dissolved in ethyl acetate, filtered and concentrated giving the desired compound in 98%. Crystals were obtained from an ethyl acetate/diethyl ether solution; m.p. 110–112 °C, [α]_D= -13.4 (c 1.0, CH₂Cl₂). IR (KBr) 3447, 1655, 1591, 1372 cm^{-1. 1}H NMR (400 MHz, CDCl₃) d(p.p.m., JHz): 1.51 (m, 1H), 2.05 (m, 3H), 2.99 (s, 3H), 3.01 (s, 3H), 3.12 (m, 1H), 3.57 (td, J = 7.8, 11.0 Hz, 1H), 3.85 (dd, J = 7.24, 9.28 Hz, 1H). HRMS (FAB+): Calcd for C₉H₁₃NO₂S: 199.0667. Found: 199.0665.

Refinement

H atoms were placed in geometrically idealized positions and refined as riding on their parent atoms, with C—H distances fixed to 0.960 (methyl CH₃) and 0.980 Å (methine CH) and with U_iso(H) = 1.5U_eq(methyl C) or 1.2U_eq(C).

Figures

Fig. 1.

The molecular structure of title compound, with atom labels and 50% probability displacement ellipsoids for non-H atoms.

Crystal data

C9H13NO2S	Dx = 1.406 Mg m−3
Mr = 199.26	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, P212121	Cell parameters from 4129 reflections
a = 5.8761 (3) Å	θ = 3.5–26.0°
b = 9.0858 (5) Å	µ = 0.31 mm−1
c = 17.7107 (9) Å	T = 130 K
V = 945.56 (9) Å3	Plate, colourless
Z = 4	0.46 × 0.33 × 0.07 mm
F(000) = 424

Data collection

Oxford Xcalibur Atlas Gemini diffractometer	1873 independent reflections
Graphite monochromator	1736 reflections with I > 2σ(I)
Detector resolution: 10.4685 pixels mm-1	Rint = 0.037
ω scans	θmax = 26.1°, θmin = 3.7°
Absorption correction: analytical (CrysAlis PRO; Oxford Diffraction, 2002)	h = −7→7
Tmin = 0.895, Tmax = 0.976	k = −10→11
6356 measured reflections	l = −18→21

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)] = 0.027	H-atom parameters constrained
wR(F2) = 0.065	w = 1/[σ2(Fo2) + (0.0385P)2] where P = (Fo2 + 2Fc2)/3
S = 1.04	(Δ/σ)max < 0.001
1873 reflections	Δρmax = 0.20 e Å−3
120 parameters	Δρmin = −0.26 e Å−3
0 restraints	Absolute structure: Flack (1983), with 758 Friedel pairs
Primary atom site location: structure-invariant direct methods	Flack parameter: −0.07 (7)

Special details

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

	x	y	z	Uiso*/Ueq
S1	0.72287 (7)	0.59085 (4)	0.01093 (2)	0.01852 (12)
O1	0.6977 (3)	0.26576 (13)	0.09183 (7)	0.0293 (3)
O2	0.4048 (2)	0.74463 (12)	0.13031 (6)	0.0229 (3)
N1	0.4198 (2)	0.53624 (15)	0.20467 (8)	0.0172 (3)
C1	0.4721 (3)	0.61719 (18)	0.14100 (9)	0.0172 (4)
C2	0.6056 (3)	0.52340 (19)	0.09255 (9)	0.0188 (4)
C3	0.6092 (3)	0.37738 (18)	0.11921 (10)	0.0193 (4)
C4	0.4806 (3)	0.38002 (17)	0.19391 (9)	0.0173 (4)
H4	0.5823	0.3464	0.2358	0.021*
C5	0.2519 (3)	0.30179 (17)	0.19885 (10)	0.0216 (4)
H5A	0.2702	0.1975	0.2138	0.026*
H5B	0.1682	0.3069	0.1504	0.026*
C6	0.1329 (3)	0.3908 (2)	0.26032 (10)	0.0228 (4)
H6A	0.1871	0.3614	0.3111	0.027*
H6B	−0.0341	0.3772	0.2579	0.027*
C7	0.1984 (3)	0.55113 (19)	0.24287 (10)	0.0222 (4)
H7A	0.0847	0.5982	0.2094	0.027*
H7B	0.2125	0.6096	0.2898	0.027*
C8	1.0123 (3)	0.5311 (2)	0.01195 (12)	0.0296 (4)
H8A	1.0832	0.5535	−0.0368	0.044*
H8B	1.0179	0.4248	0.0209	0.044*
H8C	1.0946	0.5823	0.0523	0.044*
C9	0.6187 (4)	0.4744 (3)	−0.06291 (11)	0.0370 (5)
H9A	0.6929	0.5007	−0.1106	0.056*
H9B	0.4538	0.4873	−0.0679	0.056*
H9C	0.6523	0.3715	−0.0507	0.056*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
S1	0.0209 (2)	0.0186 (2)	0.0160 (2)	0.00209 (17)	0.00126 (16)	0.00138 (16)
O1	0.0388 (8)	0.0202 (6)	0.0290 (7)	0.0101 (6)	0.0091 (6)	0.0018 (5)
O2	0.0311 (7)	0.0156 (6)	0.0220 (6)	0.0036 (5)	0.0008 (6)	−0.0003 (5)
N1	0.0200 (8)	0.0147 (7)	0.0170 (7)	−0.0002 (6)	0.0002 (6)	−0.0023 (6)
C1	0.0173 (9)	0.0194 (9)	0.0150 (8)	−0.0035 (7)	−0.0038 (7)	−0.0014 (7)
C2	0.0205 (9)	0.0190 (8)	0.0169 (9)	0.0022 (8)	0.0023 (8)	0.0016 (7)
C3	0.0178 (9)	0.0193 (9)	0.0209 (9)	−0.0004 (7)	−0.0012 (7)	0.0003 (7)
C4	0.0176 (8)	0.0165 (8)	0.0179 (9)	0.0031 (7)	−0.0021 (7)	0.0013 (7)
C5	0.0213 (10)	0.0186 (8)	0.0250 (9)	−0.0018 (8)	−0.0005 (8)	−0.0005 (7)
C6	0.0166 (9)	0.0247 (10)	0.0272 (9)	−0.0060 (8)	0.0030 (7)	−0.0001 (8)
C7	0.0236 (10)	0.0210 (8)	0.0221 (9)	−0.0006 (8)	0.0067 (8)	−0.0029 (7)
C8	0.0191 (9)	0.0384 (10)	0.0314 (10)	0.0013 (8)	0.0018 (8)	0.0086 (9)
C9	0.0366 (13)	0.0563 (13)	0.0181 (10)	−0.0149 (11)	−0.0006 (9)	−0.0074 (10)

Geometric parameters (Å, º)

S1—C2	1.7146 (17)	C5—H5A	0.99
S1—C8	1.7851 (18)	C5—H5B	0.99
S1—C9	1.7900 (19)	C6—C7	1.538 (3)
O1—C3	1.238 (2)	C6—H6A	0.99
O2—C1	1.238 (2)	C6—H6B	0.99
N1—C1	1.381 (2)	C7—H7A	0.99
N1—C7	1.473 (2)	C7—H7B	0.99
N1—C4	1.476 (2)	C8—H8A	0.98
C1—C2	1.442 (2)	C8—H8B	0.98
C2—C3	1.408 (2)	C8—H8C	0.98
C3—C4	1.524 (2)	C9—H9A	0.98
C4—C5	1.523 (2)	C9—H9B	0.98
C4—H4	1	C9—H9C	0.98
C5—C6	1.526 (2)
C2—S1—C8	105.40 (9)	H5A—C5—H5B	109.3
C2—S1—C9	105.50 (9)	C5—C6—C7	104.11 (14)
C8—S1—C9	98.84 (11)	C5—C6—H6A	110.9
C1—N1—C7	121.50 (14)	C7—C6—H6A	110.9
C1—N1—C4	110.68 (13)	C5—C6—H6B	110.9
C7—N1—C4	111.17 (13)	C7—C6—H6B	110.9
O2—C1—N1	123.51 (15)	H6A—C6—H6B	109
O2—C1—C2	129.47 (15)	N1—C7—C6	103.08 (13)
N1—C1—C2	106.99 (14)	N1—C7—H7A	111.1
C3—C2—C1	111.43 (15)	C6—C7—H7A	111.1
C3—C2—S1	127.84 (13)	N1—C7—H7B	111.1
C1—C2—S1	120.61 (13)	C6—C7—H7B	111.1
O1—C3—C2	130.27 (16)	H7A—C7—H7B	109.1
O1—C3—C4	124.12 (15)	S1—C8—H8A	109.5
C2—C3—C4	105.60 (14)	S1—C8—H8B	109.5
N1—C4—C5	103.19 (13)	H8A—C8—H8B	109.5
N1—C4—C3	104.31 (13)	S1—C8—H8C	109.5
C5—C4—C3	118.71 (14)	H8A—C8—H8C	109.5
N1—C4—H4	110	H8B—C8—H8C	109.5
C5—C4—H4	110	S1—C9—H9A	109.5
C3—C4—H4	110	S1—C9—H9B	109.5
C4—C5—C6	101.43 (13)	H9A—C9—H9B	109.5
C4—C5—H5A	111.5	S1—C9—H9C	109.5
C6—C5—H5A	111.5	H9A—C9—H9C	109.5
C4—C5—H5B	111.5	H9B—C9—H9C	109.5
C6—C5—H5B	111.5
C7—N1—C1—O2	34.5 (2)	S1—C2—C3—C4	179.92 (13)
C4—N1—C1—O2	167.62 (15)	C1—N1—C4—C5	−116.83 (15)
C7—N1—C1—C2	−143.55 (15)	C7—N1—C4—C5	21.34 (17)
C4—N1—C1—C2	−10.39 (18)	C1—N1—C4—C3	7.84 (18)
O2—C1—C2—C3	−168.74 (17)	C7—N1—C4—C3	146.01 (13)
N1—C1—C2—C3	9.1 (2)	O1—C3—C4—N1	176.79 (16)
O2—C1—C2—S1	7.6 (3)	C2—C3—C4—N1	−2.07 (18)
N1—C1—C2—S1	−174.58 (12)	O1—C3—C4—C5	−69.1 (2)
C8—S1—C2—C3	−52.18 (19)	C2—C3—C4—C5	112.01 (16)
C9—S1—C2—C3	51.81 (19)	N1—C4—C5—C6	−37.44 (16)
C8—S1—C2—C1	132.16 (15)	C3—C4—C5—C6	−152.13 (15)
C9—S1—C2—C1	−123.85 (16)	C4—C5—C6—C7	40.51 (17)
C1—C2—C3—O1	177.13 (18)	C1—N1—C7—C6	136.85 (15)
S1—C2—C3—O1	1.1 (3)	C4—N1—C7—C6	3.89 (18)
C1—C2—C3—C4	−4.1 (2)	C5—C6—C7—N1	−27.69 (17)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4···O2i	1.00	2.55	3.4145 (19)	145
C7—H7B···O1ii	0.99	2.59	3.570 (2)	173

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