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Acta Cryst. (2008). E64, o2089-o2090    [ doi:10.1107/S1600536808031838 ]

(3RS,4SR)-Methyl 4-(2-chloro-5,8-dimethoxyquinolin-3-yl)-1-phenylpyrrolidine-3-carboxylate

S. Benzerka, A. Bouraiou, S. Bouacida, S. Rhouati and A. Belfaitah

Abstract top

The molecule of the title compound, C23H23ClN2O4, contains a quinolyl unit linked to a functionalized pyrrolidine system with a 3,4-trans arrangement of the substituents. The unit cell contains two stereoisomers that have the absolute stereochemistry 3S,4R and 3R,4S. The pyrrolidine ring adopts a twist conformation with pseudo-rotation parameters P = 258.2 (3)° and [tau](M) = 35.3 (1)°. The packing is stabilized by C-H...[pi] interactions and offset [pi]-[pi] stacking (centroid-to-centroid distance = 3.849 Å, interplanar distance = 3.293 Å and slippage = 1.994 Å) between phenyl rings, leading to a two-dimensional network.

Comment top

Quinolines derivatives have attracted considerable interest for many years due to their presence in the skeleton of a large number of bioactive compounds and natural products (Padwa et al., 1999; Sahu et al. 2002). For example, quinoline alkaloids, such as quinine, chloroquin, mefloquine and amodiaquine, are used as efficient drugs for the treatment of malaria (Robert & Meunier, 1998; Dow et al., 2006). On the other hand, pyrrolidine containing compounds are also of significant importance because of their biological activities and widespread employment in catalysis (Witherup et al., 1995; Kravchenko et al., 2005). As a part of our program related to the preparation and biological evaluation of quinolyl derivatives (Belfaitah et al., 2006; Bouraiou et al., 2008, 2007a,b; Rezig et al., 2000; Moussaoui et al., 2002), we have previously reported the preparation of some 3-pyrrolylquinoline derivatives via an 1,3-dipolar cycloaddition/oxydation key sequence from quinolinyl α,β-unsaturated esters as starting materials (Menasra et al., 2005). In a continuation of our efforts in this area, we report here the crystal structure of new N-phenylpyrrolidine derivative bearing a quinoline ring at C-3 and ester group at C-4 via an 1,3-dipolar cycloaddition reaction.

The asymmetric unit of title compound contains a quinolyl unit linked to a functionalized pyrrolidine system with a 3,4-trans arrangement of the substituents (Fig. 1). The two rings of quinolyl moiety are fused in an axial fashion and form a dihedral angle of 0.67 (6)° and this quasi plane system forms dihedral angles of 83.76 (7)° with the phenyl ring.The pyrrolidine was obtained with conservation of the stereochemistry of starting alkene, giving only one diastereoisomer with no evidence of any other isomers in the 1H NMR spectra or thin-layer chromatography of the crude product. X-ray crystallography of (I) showed an asymmetric unit which contains only one stereoisomer and the analysis of the unit cell demonstrate that the second stereoisomer is generated via a symmetry element. The two stereoisomers have for each one, the absolute stereochemistry 3S,4R and 3R,4S of the new stereocenters created in the cycloaddition reactions.

The pyrrolidine ring adopts twist conformation on C13—C14 with pseudorotation parameters P = 258.2 (3)° and τ(M) = 35.3 (1)° (Rao et al., 1981), the C13 atom deviates by 0.213 (2)Å from the mean plane through the remaining atoms.

The packing is stabilized by C—H···π interaction involving the C17—C22 phenyl ring (Table 1). Offset π···π stacking between this phenyl ring and the symmetry (-x, -y, -z) related ring might also be considered with a centroid-to-centroid distance of 3.849 Å, an interplanar distance of 3.293Å and a slippage of 1.994Å (Spek, 2003). These weak interactions build up a two dimensional network (Fig. 2).

Related literature top

For general background, see: Padwa et al. (1999); Sahu et al. (2002); Robert & Meunier (1998); Dow et al. (2006); Witherup et al. (1995); Kravchenko et al. (2005); Bouraiou et al. (2008); Rezig et al. (2000); Moussaoui et al. (2002); Menasra et al. (2005); Rao et al. (1981). For related structures, see: Belfaitah et al. (2006); Bouraiou et al. (2007a,b).

Experimental top

The title compound I was synthesized by refluxing 1.0 mmol of (E)-methyl 3-(2-chloro-5,8-dimethoxyquinolin-3-yl) acrylate, 2.0 mmol of N-phenylglycine, and 5.0 mmol of CH2O in dry toluene (5.10-3 M). The contents were then cooled and filtered off and the filtrate was concentrated under reduced pressure. The residue was subjected to column chromatography (silica gel, eluent: CH2Cl2) to afford pure product. Crystals suitable for X-ray analysis were obtained by slow evaporation of a dichloromethane solution of (I).

Refinement top

All H atoms were localized on Fourier maps but introduced in calculated positions and treated as riding on their parent C atom.

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR2002 (Burla et al., 2003); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and CAMERON (Pearce et al., 2000); software used to prepare material for publication: PLATON (Spek, 2003) and WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound with the atom-labeling scheme.Displacement ellipsoids are drawn at the 50% probability level. H atoms are represnted as small spheres of arbitrary radii.
[Figure 2] Fig. 2. Partial packing view showing the C—H···π and π-π interactions drawn as dashed lines. H atoms not involved in H bonding interactions have been omitted for clarity.
(3RS,4SR)-Methyl 4-(2-chloro-5,8-dimethoxyquinolin-3-yl)-1-phenylpyrrolidine-3-carboxylate top
Crystal data top
C23H23ClN2O4F(000) = 896
Mr = 426.88Dx = 1.381 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 4717 reflections
a = 9.579 (1) Åθ = 2.0–27.5°
b = 17.518 (1) ŵ = 0.22 mm−1
c = 12.944 (2) ÅT = 296 K
β = 109.01 (2)°Needle, white
V = 2053.6 (5) Å30.15 × 0.06 × 0.05 mm
Z = 4
Data collection top
Nonius KappaCCD
diffractometer		3062 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.026
graphiteθmax = 27.5°, θmin = 2.0°
φ scans, and ω scans with κ offsetsh = −12→12
9271 measured reflectionsk = −22→22
4717 independent reflectionsl = −16→16
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.055Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.178H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.102P)2 + 0.336P]
where P = (Fo2 + 2Fc2)/3
4717 reflections(Δ/σ)max < 0.001
274 parametersΔρmax = 0.38 e Å−3
0 restraintsΔρmin = −0.33 e Å−3
Crystal data top
C23H23ClN2O4V = 2053.6 (5) Å3
Mr = 426.88Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.579 (1) ŵ = 0.22 mm−1
b = 17.518 (1) ÅT = 296 K
c = 12.944 (2) Å0.15 × 0.06 × 0.05 mm
β = 109.01 (2)°
Data collection top
Nonius KappaCCD
diffractometer		3062 reflections with I > 2σ(I)
9271 measured reflectionsRint = 0.026
4717 independent reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.055H-atom parameters constrained
wR(F2) = 0.178Δρmax = 0.38 e Å−3
S = 1.03Δρmin = −0.33 e Å−3
4717 reflectionsAbsolute structure: ?
274 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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 > 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 (Å2) top
xyzUiso*/Ueq
C20.4396 (2)0.31838 (12)−0.07671 (19)0.0457 (5)
C30.3691 (3)0.26052 (12)−0.03567 (19)0.0482 (5)
C40.3895 (3)0.18796 (12)−0.0673 (2)0.0494 (5)
H40.34460.1473−0.04430.059*
C50.4777 (2)0.17338 (11)−0.13446 (18)0.0417 (5)
C60.5028 (3)0.09863 (12)−0.16864 (19)0.0463 (5)
C70.5869 (3)0.08969 (13)−0.2347 (2)0.0514 (5)
H70.60210.0411−0.25800.062*
C80.6515 (3)0.15355 (14)−0.2683 (2)0.0526 (6)
H80.70890.1461−0.31310.063*
C90.6317 (2)0.22567 (13)−0.23653 (18)0.0465 (5)
C100.5433 (2)0.23684 (12)−0.16778 (17)0.0417 (5)
C110.4590 (4)−0.03500 (14)−0.1605 (3)0.0733 (8)
H11A0.4239−0.0394−0.23870.110*
H11B0.4054−0.0697−0.13000.110*
H11C0.5623−0.0473−0.13340.110*
C120.7822 (3)0.28219 (17)−0.3307 (3)0.0708 (8)
H12A0.85970.2464−0.29730.106*
H12B0.82470.3308−0.33770.106*
H12C0.72440.2640−0.40170.106*
C130.2718 (3)0.27974 (13)0.0337 (2)0.0520 (6)
H130.31020.32510.07810.062*
C140.1144 (3)0.29516 (14)−0.0433 (2)0.0559 (6)
H140.11700.3162−0.11290.067*
C150.0444 (3)0.21579 (13)−0.0605 (2)0.0548 (6)
H15A−0.05960.2188−0.06820.066*
H15B0.05440.1921−0.12550.066*
C160.2513 (3)0.21506 (13)0.10654 (19)0.0487 (5)
H16A0.33850.18300.13050.058*
H16B0.23140.23510.17020.058*
C170.0583 (2)0.11625 (12)0.08000 (18)0.0441 (5)
C18−0.0791 (3)0.08503 (13)0.0195 (2)0.0500 (5)
H18−0.12770.1023−0.05110.060*
C19−0.1420 (3)0.02882 (15)0.0646 (2)0.0619 (7)
H19−0.23330.00890.02370.074*
C20−0.0738 (3)0.00156 (15)0.1677 (3)0.0694 (8)
H20−0.1182−0.03610.19710.083*
C210.0624 (3)0.03104 (15)0.2276 (2)0.0651 (7)
H210.11040.01270.29760.078*
C220.1281 (3)0.08755 (13)0.1845 (2)0.0519 (6)
H220.21990.10660.22590.062*
C230.0291 (3)0.34891 (17)0.0089 (3)0.0662 (7)
C24−0.1671 (4)0.4343 (2)−0.0293 (4)0.1079 (13)
H24A−0.25170.4048−0.02970.162*
H24B−0.19850.4769−0.07810.162*
H24C−0.11760.45270.04330.162*
Cl10.41733 (7)0.41375 (3)−0.04310 (5)0.0582 (2)
N10.5228 (2)0.30920 (10)−0.13716 (15)0.0447 (4)
N20.1249 (2)0.17236 (11)0.03698 (15)0.0487 (5)
O10.4375 (2)0.04110 (9)−0.13011 (16)0.0635 (5)
O20.6896 (2)0.29035 (10)−0.26382 (16)0.0650 (5)
O30.0479 (4)0.3523 (2)0.1042 (3)0.1496 (14)
O4−0.0678 (3)0.38737 (15)−0.0644 (2)0.0947 (8)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C20.0513 (12)0.0368 (10)0.0521 (12)−0.0025 (9)0.0211 (10)0.0011 (9)
C30.0518 (13)0.0418 (11)0.0572 (14)−0.0015 (9)0.0262 (11)−0.0001 (9)
C40.0542 (13)0.0390 (10)0.0623 (14)−0.0046 (9)0.0292 (11)0.0025 (10)
C50.0422 (11)0.0385 (10)0.0478 (12)−0.0029 (8)0.0192 (9)0.0003 (8)
C60.0469 (12)0.0387 (11)0.0562 (13)−0.0012 (9)0.0210 (10)−0.0010 (9)
C70.0578 (14)0.0439 (11)0.0571 (14)0.0027 (10)0.0249 (11)−0.0048 (10)
C80.0566 (14)0.0570 (13)0.0535 (13)0.0023 (11)0.0306 (11)0.0002 (10)
C90.0472 (12)0.0485 (12)0.0480 (12)−0.0020 (9)0.0215 (10)0.0055 (9)
C100.0404 (11)0.0412 (11)0.0447 (12)−0.0007 (8)0.0155 (9)0.0037 (8)
C110.088 (2)0.0378 (12)0.106 (2)−0.0050 (13)0.0492 (18)−0.0099 (13)
C120.0718 (18)0.0793 (18)0.0783 (19)0.0021 (14)0.0476 (16)0.0170 (15)
C130.0581 (14)0.0469 (12)0.0550 (14)−0.0054 (10)0.0239 (11)−0.0039 (10)
C140.0670 (15)0.0525 (13)0.0547 (14)0.0026 (11)0.0288 (12)0.0043 (11)
C150.0602 (14)0.0527 (13)0.0488 (13)−0.0032 (11)0.0142 (11)0.0016 (10)
C160.0485 (12)0.0512 (12)0.0483 (12)−0.0079 (10)0.0183 (10)−0.0035 (9)
C170.0476 (12)0.0414 (10)0.0514 (12)−0.0012 (9)0.0270 (10)−0.0052 (9)
C180.0488 (13)0.0509 (12)0.0552 (13)−0.0036 (10)0.0238 (11)−0.0106 (10)
C190.0585 (15)0.0552 (13)0.0839 (19)−0.0132 (12)0.0394 (14)−0.0167 (13)
C200.081 (2)0.0564 (15)0.089 (2)−0.0128 (14)0.0530 (18)0.0000 (14)
C210.0787 (18)0.0627 (15)0.0649 (16)0.0021 (14)0.0386 (14)0.0115 (12)
C220.0537 (13)0.0528 (13)0.0548 (14)−0.0039 (10)0.0252 (11)0.0017 (10)
C230.0716 (17)0.0722 (17)0.0677 (18)0.0082 (14)0.0403 (15)0.0035 (14)
C240.075 (2)0.119 (3)0.134 (3)0.026 (2)0.040 (2)−0.042 (3)
Cl10.0772 (4)0.0366 (3)0.0688 (4)−0.0023 (3)0.0349 (3)−0.0035 (2)
N10.0473 (10)0.0404 (9)0.0491 (10)−0.0048 (8)0.0194 (8)0.0008 (7)
N20.0488 (10)0.0526 (11)0.0449 (10)−0.0100 (8)0.0153 (8)0.0012 (8)
O10.0766 (12)0.0357 (8)0.0950 (14)−0.0065 (8)0.0510 (11)−0.0048 (8)
O20.0799 (12)0.0537 (10)0.0820 (13)−0.0051 (9)0.0546 (11)0.0084 (8)
O30.196 (3)0.168 (3)0.098 (2)0.098 (3)0.065 (2)0.008 (2)
O40.0841 (15)0.1037 (17)0.0949 (17)0.0388 (13)0.0272 (13)−0.0179 (13)
Geometric parameters (Å, °) top
C2—N11.296 (3)C13—H130.9800
C2—C31.414 (3)C14—C151.528 (3)
C2—Cl11.757 (2)C14—C231.540 (4)
C3—C41.369 (3)C14—H140.9800
C3—C131.528 (3)C15—N21.460 (3)
C4—C51.419 (3)C15—H15A0.9700
C4—H40.9300C15—H15B0.9700
C5—C101.412 (3)C16—N21.458 (3)
C5—C61.427 (3)C16—H16A0.9700
C6—C71.362 (3)C16—H16B0.9700
C6—O11.363 (3)C17—N21.384 (3)
C7—C81.413 (3)C17—C221.393 (3)
C7—H70.9300C17—C181.405 (3)
C8—C91.361 (3)C18—C191.379 (3)
C8—H80.9300C18—H180.9300
C9—O21.358 (3)C19—C201.368 (4)
C9—C101.427 (3)C19—H190.9300
C10—N11.361 (3)C20—C211.382 (4)
C11—O11.424 (3)C20—H200.9300
C11—H11A0.9600C21—C221.384 (3)
C11—H11B0.9600C21—H210.9300
C11—H11C0.9600C22—H220.9300
C12—O21.434 (3)C23—O31.190 (4)
C12—H12A0.9600C23—O41.281 (4)
C12—H12B0.9600C24—O41.439 (3)
C12—H12C0.9600C24—H24A0.9600
C13—C161.527 (3)C24—H24B0.9600
C13—C141.536 (4)C24—H24C0.9600
N1—C2—C3126.9 (2)C13—C14—H14110.4
N1—C2—Cl1114.55 (15)C23—C14—H14110.4
C3—C2—Cl1118.52 (17)N2—C15—C14105.40 (19)
C4—C3—C2114.9 (2)N2—C15—H15A110.7
C4—C3—C13123.70 (19)C14—C15—H15A110.7
C2—C3—C13121.36 (19)N2—C15—H15B110.7
C3—C4—C5121.5 (2)C14—C15—H15B110.7
C3—C4—H4119.3H15A—C15—H15B108.8
C5—C4—H4119.3N2—C16—C13104.32 (19)
C10—C5—C4117.30 (19)N2—C16—H16A110.9
C10—C5—C6119.41 (18)C13—C16—H16A110.9
C4—C5—C6123.29 (18)N2—C16—H16B110.9
C7—C6—O1125.5 (2)C13—C16—H16B110.9
C7—C6—C5119.60 (19)H16A—C16—H16B108.9
O1—C6—C5114.91 (18)N2—C17—C22120.6 (2)
C6—C7—C8120.6 (2)N2—C17—C18121.5 (2)
C6—C7—H7119.7C22—C17—C18117.8 (2)
C8—C7—H7119.7C19—C18—C17120.1 (2)
C9—C8—C7121.6 (2)C19—C18—H18120.0
C9—C8—H8119.2C17—C18—H18120.0
C7—C8—H8119.2C20—C19—C18121.8 (3)
O2—C9—C8126.0 (2)C20—C19—H19119.1
O2—C9—C10115.04 (19)C18—C19—H19119.1
C8—C9—C10118.99 (19)C19—C20—C21118.7 (2)
N1—C10—C5121.56 (18)C19—C20—H20120.6
N1—C10—C9118.70 (18)C21—C20—H20120.6
C5—C10—C9119.73 (19)C20—C21—C22120.8 (3)
O1—C11—H11A109.5C20—C21—H21119.6
O1—C11—H11B109.5C22—C21—H21119.6
H11A—C11—H11B109.5C21—C22—C17120.8 (2)
O1—C11—H11C109.5C21—C22—H22119.6
H11A—C11—H11C109.5C17—C22—H22119.6
H11B—C11—H11C109.5O3—C23—O4124.8 (3)
O2—C12—H12A109.5O3—C23—C14124.3 (3)
O2—C12—H12B109.5O4—C23—C14110.9 (2)
H12A—C12—H12B109.5O4—C24—H24A109.5
O2—C12—H12C109.5O4—C24—H24B109.5
H12A—C12—H12C109.5H24A—C24—H24B109.5
H12B—C12—H12C109.5O4—C24—H24C109.5
C16—C13—C3115.15 (19)H24A—C24—H24C109.5
C16—C13—C14103.61 (19)H24B—C24—H24C109.5
C3—C13—C14108.3 (2)C2—N1—C10117.82 (18)
C16—C13—H13109.8C17—N2—C16120.98 (18)
C3—C13—H13109.8C17—N2—C15122.38 (19)
C14—C13—H13109.8C16—N2—C15111.38 (18)
C15—C14—C13103.03 (19)C6—O1—C11117.75 (19)
C15—C14—C23110.5 (2)C9—O2—C12117.3 (2)
C13—C14—C23111.8 (2)C23—O4—C24117.5 (3)
C15—C14—H14110.4
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C12—H12B···Cg1i0.962.673.601 (3)164
Symmetry codes: (i) x+1, −y+1/2, z−1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C12—H12B···Cg1i0.962.673.601 (3)164
Symmetry codes: (i) x+1, −y+1/2, z−1/2.
Acknowledgements top

We are grateful to Professor Lahcéne Ouahab (Organométalliques et Materiaux Moléculaire, Université de Rennes I, France) for data collection facilities and Professor Abdelmadjid Debache (PHYSYNOR, Université Mentouri Constantine, Algeria) for his assistance. Thanks are due to MESRS (Ministére de l'Enseignement Supérieur et de la Recherche Scientifique) for financial support.

references
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