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Acta Cryst. (2008). E64, o2115-o2116    [ doi:10.1107/S1600536808032546 ]

Ethyl 4-(2-chloroquinolin-3-yl)-1-phenyl-1H-pyrrole-3-carboxylate

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

Abstract top

In the molecule of the title compound, C22H17ClN2O2, the dihedral angles formed by the pyrrole ring with the quinoline and phenyl rings are 67.93 (8) and 28.40 (11)°, respectively. In the crystal structure, molecules are linked into dimers by intermolecular C-H...O hydrogen bonds.

Comment top

Heterocyclic compounds and particularly five and six membered ring compounds occupy a prominent place among various classes of organic compounds for their diverse biological activities. Among a wide variety of heterocycles that have been explored for developing pharmaceutically important molecules (Raj Amal et al., 2003), quinolines have played an important role in medicine chemistry (Wright et al., 2001; Sahu et al., 2002). Some of them have received considerable attention due to their presence in numerous natural products along with their wide ranging application as drugs, pharmaceutical and agrochemicals (Michael, 1997). Pyrroles are an important class of heterocyclic compounds and are widely used in synthetic organic chemistry and material science (Corvo & Pereira, 2002; Harrison et al., 2006). Pyrroles are often seen as building blocks in naturally occurring and biologically active compounds such as heme, chlorophyll and vitamin B12 (Demir et al., 2005; Bigg & Bonnaud, 1994; Tsukamoto et al., 2001). Syntheses of pyrroloquinolines derivatives were not particularly numerous in the literature before the initial report of the unique alkaloids (Witherup et al., 1995). In a continuation of our program on the synthesis and biological evaluation of quinolines derivatives (Belfaitah et al., 2006; Bouraiou et al., 2008; Rezig et al., 2000; Moussaoui et al., 2002), we have elaborated an efficient route for the synthesis of 3-pyrrolylquinolines by dehydrogenation of 3-pyrrolidinyl quinolines using activated manganese dioxide in refluxing THF during 5 h (Menasra et al., 2005; Benzerka et al. 2008). We report here the crystal structure of a new N-phenylpyrrole derivative bearing a quinoline ring at C-3 and an ester group at C-4.

The molecular structure and the atom-numbering scheme of the title compound are shown in Fig. 1. The quinoline ring system is essentially planar, the dihedral angle formed by the six-membered rings being only 0.64 (8)°. The dihedral angles between the pyrrole ring and the quinoline and phenyl rings are 67.93 (8) and 28.40 (11)°, respectively. The geometric parameters are in agreement with those of other structures possessing a quinolyl substituent previously reported in the literature (Belfaitah et al., 2006; Bouraiou et al., 2008). In the crystal structure (Fig. 2), molecules are linked into dimers by intermolecular C—H···O hydrogen bonds (Table 1).

Related literature top

For general background, see: Corvo & Pereira (2002); Harrison et al. (2006); Wright et al. (2001); Sahu et al. (2002); Michael (1997); Rezig et al. (2000); Raj Amal et al. (2003); Witherup et al. (1995); Moussaoui et al., 2002). For related structures, see: Belfaitah et al. (2006); Bouraiou et al. (2008);. For details of the synthesis, see: Menasra et al. (2005); Benzerka et al. (2008). For pyrroles as building blocks in naturally occurring and biologically active compounds such as heme, chlorophyll and vitamin B12, see: Bigg & Bonnaud (1994); Demir et al. (2005); Tsukamoto et al. (2001);

Experimental top

To a 0.1 M solution of ethyl 4-(2-chloroquinolin-3-yl)-1-phenylpyrrole -3-carboxylate (1.5 mmol) in dry THF (15 ml) 2.5 equivalents of activated MnO2 were added. The mixture was refluxed for 2.5 h. The same amount of activated MnO2 was then added, and the reflux was continued for an additional 2.5 h. After cooling, the mixture was diluted with THF, filtered through Celite and washed with THF (5x5 ml). The filtrate was concentrated under reduced pressure, diluted with CH2Cl2 and washed with water (2x5 ml). The organic layers were separated and dried over anhydrous MgSO4. The filtrate was concentrated and the residue was purified by flash chromatography on silica gel using AcOEt/pentane (2:1 v/v) as eluent to afford the corresponding pure pyrrole derivative. Crystals suitable for X-ray analysis were obtained by slow evaporation of the solvent.

Refinement top

All H atoms were introduced in calculated positions and treated as riding, with C—H = 0.93-0.97 Å, and with Uiso(H) = 1.2 Ueq(C) or 1.5 Ueq(C) for methyl hydrogen atoms.

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/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: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg & Berndt, 2001); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with the atomic labelling scheme. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. Packing diagram of the title compound viewed along the b axis.
Ethyl 4-(2-chloroquinolin-3-yl)-1-phenyl-1H-pyrrole-3-carboxylate top
Crystal data top
C22H17ClN2O2F(000) = 1568
Mr = 376.83Dx = 1.328 Mg m−3
Monoclinic, I2/aMo Kα radiation, λ = 0.71073 Å
Hall symbol: -I 2yaCell parameters from 9812 reflections
a = 20.2021 (6) Åθ = 5.1–25.1°
b = 8.0500 (1) ŵ = 0.22 mm−1
c = 24.0238 (7) ÅT = 296 K
β = 105.29 (2)°Needle, white
V = 3768.6 (4) Å30.15 × 0.06 × 0.05 mm
Z = 8
Data collection top
Nonius KappaCCD
diffractometer		2343 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.043
graphiteθmax = 25.1°, θmin = 5.1°
φ scans, and ω scans with κ offsetsh = −23→24
9812 measured reflectionsk = −9→9
3315 independent reflectionsl = −28→28
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)] = 0.051Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.142H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.103P)2 + 0.3358P]
where P = (Fo2 + 2Fc2)/3
3315 reflections(Δ/σ)max < 0.001
244 parametersΔρmax = 0.29 e Å−3
0 restraintsΔρmin = −0.27 e Å−3
Crystal data top
C22H17ClN2O2V = 3768.6 (4) Å3
Mr = 376.83Z = 8
Monoclinic, I2/aMo Kα radiation
a = 20.2021 (6) ŵ = 0.22 mm−1
b = 8.0500 (1) ÅT = 296 K
c = 24.0238 (7) Å0.15 × 0.06 × 0.05 mm
β = 105.29 (2)°
Data collection top
Nonius KappaCCD
diffractometer		2343 reflections with I > 2σ(I)
9812 measured reflectionsRint = 0.043
3315 independent reflectionsθmax = 25.1°
Refinement top
R[F2 > 2σ(F2)] = 0.051H-atom parameters constrained
wR(F2) = 0.142Δρmax = 0.29 e Å−3
S = 1.02Δρmin = −0.27 e Å−3
3315 reflectionsAbsolute structure: ?
244 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
Cl10.12476 (3)0.20796 (10)0.35827 (3)0.0669 (3)
O10.19940 (10)−0.3023 (3)0.31308 (8)0.0722 (6)
C130.12321 (12)−0.1022 (3)0.25970 (10)0.0454 (6)
N20.10945 (10)0.0124 (3)0.17336 (8)0.0480 (5)
N10.00661 (12)0.1516 (3)0.37746 (9)0.0607 (6)
C3−0.04742 (13)−0.0147 (3)0.27328 (11)0.0515 (6)
H3−0.0658−0.06710.23810.062*
O20.11506 (10)−0.2065 (3)0.34790 (8)0.0696 (6)
C200.15071 (12)−0.2127 (3)0.30819 (10)0.0489 (6)
C120.14907 (12)−0.0931 (3)0.21243 (10)0.0483 (6)
H120.1874−0.14980.20790.058*
C10.04143 (13)0.1247 (3)0.34028 (10)0.0509 (6)
C140.12066 (13)0.0599 (3)0.11921 (10)0.0507 (6)
C100.06434 (12)0.0057 (3)0.24895 (10)0.0445 (5)
C110.05718 (12)0.0714 (3)0.19565 (10)0.0490 (6)
H110.02270.14440.17700.059*
C20.01905 (12)0.0392 (3)0.28691 (10)0.0455 (6)
C4−0.08852 (13)0.0083 (3)0.31192 (12)0.0555 (7)
C9−0.05921 (14)0.0900 (4)0.36430 (12)0.0601 (7)
C5−0.15703 (14)−0.0503 (4)0.30059 (15)0.0705 (8)
H5−0.1772−0.10420.26600.085*
C160.19620 (18)0.1089 (5)0.05969 (13)0.0772 (9)
H160.24020.10750.05460.093*
C150.18577 (15)0.0595 (4)0.11161 (12)0.0635 (7)
H150.22280.02580.14150.076*
C7−0.1635 (2)0.0529 (5)0.39232 (18)0.0898 (11)
H7−0.18890.06750.41900.108*
C6−0.19327 (17)−0.0274 (4)0.34045 (18)0.0827 (10)
H6−0.2382−0.06580.33300.099*
C8−0.09838 (17)0.1100 (5)0.40466 (15)0.0802 (10)
H8−0.07930.16260.43970.096*
C190.06632 (17)0.1077 (5)0.07449 (12)0.0823 (10)
H190.02190.10530.07880.099*
C170.14196 (19)0.1601 (5)0.01550 (13)0.0817 (10)
H170.14920.1950−0.01930.098*
C210.1396 (2)−0.3041 (5)0.39981 (13)0.0838 (10)
H21A0.1874−0.33360.40460.101*
H21B0.1132−0.40570.39700.101*
C180.07782 (19)0.1593 (6)0.02294 (13)0.0936 (12)
H180.04100.1940−0.00700.112*
C220.1328 (3)−0.2075 (6)0.44902 (17)0.141 (2)
H22A0.1489−0.27190.48360.211*
H22B0.0855−0.17910.44410.211*
H22C0.1596−0.10780.45190.211*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0655 (4)0.0788 (5)0.0550 (4)−0.0096 (4)0.0136 (3)−0.0156 (3)
O10.0693 (12)0.0869 (15)0.0660 (12)0.0322 (12)0.0276 (10)0.0229 (11)
C130.0496 (12)0.0459 (14)0.0408 (12)0.0020 (11)0.0120 (10)−0.0005 (10)
N20.0535 (11)0.0519 (12)0.0399 (10)0.0034 (10)0.0144 (9)0.0006 (9)
N10.0674 (14)0.0676 (15)0.0516 (12)0.0092 (12)0.0239 (11)−0.0019 (11)
C30.0547 (14)0.0473 (15)0.0517 (14)0.0051 (11)0.0127 (11)0.0025 (11)
O20.0821 (13)0.0810 (14)0.0542 (11)0.0318 (11)0.0330 (10)0.0230 (10)
C200.0540 (14)0.0486 (14)0.0461 (13)0.0043 (12)0.0170 (11)0.0016 (11)
C120.0521 (13)0.0487 (15)0.0456 (13)0.0050 (11)0.0154 (11)0.0002 (11)
C10.0578 (14)0.0514 (15)0.0443 (13)0.0036 (12)0.0153 (11)−0.0017 (11)
C140.0635 (15)0.0514 (15)0.0379 (12)0.0035 (12)0.0143 (11)0.0013 (11)
C100.0483 (12)0.0434 (13)0.0413 (12)0.0015 (11)0.0112 (10)−0.0039 (10)
C110.0502 (13)0.0497 (14)0.0466 (13)0.0060 (11)0.0116 (10)−0.0004 (11)
C20.0512 (13)0.0424 (14)0.0428 (13)0.0056 (10)0.0124 (10)0.0010 (10)
C40.0578 (15)0.0498 (15)0.0622 (16)0.0104 (12)0.0219 (12)0.0127 (13)
C90.0659 (16)0.0611 (18)0.0589 (16)0.0149 (14)0.0262 (13)0.0082 (13)
C50.0592 (16)0.0652 (19)0.091 (2)0.0067 (14)0.0263 (16)0.0113 (16)
C160.088 (2)0.093 (2)0.0613 (18)0.0162 (19)0.0381 (16)0.0154 (17)
C150.0694 (17)0.0738 (19)0.0515 (15)0.0134 (15)0.0235 (13)0.0112 (14)
C70.089 (2)0.103 (3)0.095 (3)0.020 (2)0.054 (2)0.016 (2)
C60.0617 (17)0.078 (2)0.117 (3)0.0093 (17)0.0390 (19)0.025 (2)
C80.083 (2)0.094 (3)0.078 (2)0.0131 (19)0.0467 (18)0.0042 (18)
C190.0695 (18)0.125 (3)0.0500 (16)0.014 (2)0.0121 (14)0.0124 (18)
C170.110 (3)0.094 (3)0.0478 (16)0.016 (2)0.0330 (17)0.0147 (16)
C210.113 (3)0.089 (2)0.0569 (18)0.034 (2)0.0361 (17)0.0305 (17)
C180.092 (2)0.138 (4)0.0473 (17)0.025 (2)0.0121 (16)0.0218 (19)
C220.245 (6)0.113 (4)0.061 (2)0.023 (4)0.035 (3)0.017 (2)
Geometric parameters (Å, °) top
Cl1—C11.757 (3)C9—C81.413 (4)
O1—C201.200 (3)C5—C61.362 (4)
C13—C121.371 (3)C5—H50.9300
C13—C101.440 (3)C16—C171.373 (5)
C13—C201.454 (3)C16—C151.377 (4)
N2—C121.359 (3)C16—H160.9300
N2—C111.388 (3)C15—H150.9300
N2—C141.430 (3)C7—C81.350 (5)
N1—C11.293 (3)C7—C61.392 (5)
N1—C91.376 (4)C7—H70.9300
C3—C21.366 (3)C6—H60.9300
C3—C41.411 (3)C8—H80.9300
C3—H30.9300C19—C181.383 (4)
O2—C201.339 (3)C19—H190.9300
O2—C211.446 (3)C17—C181.354 (5)
C12—H120.9300C17—H170.9300
C1—C21.420 (3)C21—C221.451 (5)
C14—C191.373 (4)C21—H21A0.9700
C14—C151.375 (4)C21—H21B0.9700
C10—C111.357 (3)C18—H180.9300
C10—C21.477 (3)C22—H22A0.9600
C11—H110.9300C22—H22B0.9600
C4—C91.405 (4)C22—H22C0.9600
C4—C51.419 (4)
C12—C13—C10107.2 (2)C6—C5—H5120.1
C12—C13—C20123.2 (2)C4—C5—H5120.1
C10—C13—C20129.5 (2)C17—C16—C15120.4 (3)
C12—N2—C11108.49 (19)C17—C16—H16119.8
C12—N2—C14126.1 (2)C15—C16—H16119.8
C11—N2—C14125.3 (2)C14—C15—C16120.0 (3)
C1—N1—C9116.8 (2)C14—C15—H15120.0
C2—C3—C4120.8 (2)C16—C15—H15120.0
C2—C3—H3119.6C8—C7—C6121.4 (3)
C4—C3—H3119.6C8—C7—H7119.3
C20—O2—C21117.9 (2)C6—C7—H7119.3
O1—C20—O2122.2 (2)C5—C6—C7120.4 (3)
O1—C20—C13125.2 (2)C5—C6—H6119.8
O2—C20—C13112.6 (2)C7—C6—H6119.8
N2—C12—C13108.8 (2)C7—C8—C9120.0 (4)
N2—C12—H12125.6C7—C8—H8120.0
C13—C12—H12125.6C9—C8—H8120.0
N1—C1—C2127.1 (2)C14—C19—C18119.8 (3)
N1—C1—Cl1115.3 (2)C14—C19—H19120.1
C2—C1—Cl1117.60 (18)C18—C19—H19120.1
C19—C14—C15119.5 (2)C18—C17—C16119.5 (3)
C19—C14—N2120.1 (2)C18—C17—H17120.2
C15—C14—N2120.4 (2)C16—C17—H17120.2
C11—C10—C13106.4 (2)O2—C21—C22109.1 (3)
C11—C10—C2125.6 (2)O2—C21—H21A109.9
C13—C10—C2128.0 (2)C22—C21—H21A109.9
C10—C11—N2109.1 (2)O2—C21—H21B109.9
C10—C11—H11125.4C22—C21—H21B109.9
N2—C11—H11125.4H21A—C21—H21B108.3
C3—C2—C1115.4 (2)C17—C18—C19120.8 (3)
C3—C2—C10121.6 (2)C17—C18—H18119.6
C1—C2—C10123.0 (2)C19—C18—H18119.6
C9—C4—C3117.9 (2)C21—C22—H22A109.5
C9—C4—C5119.1 (3)C21—C22—H22B109.5
C3—C4—C5122.9 (3)H22A—C22—H22B109.5
N1—C9—C4121.9 (2)C21—C22—H22C109.5
N1—C9—C8118.9 (3)H22A—C22—H22C109.5
C4—C9—C8119.2 (3)H22B—C22—H22C109.5
C6—C5—C4119.9 (3)
C21—O2—C20—O14.1 (4)Cl1—C1—C2—C105.3 (3)
C21—O2—C20—C13−176.6 (3)C11—C10—C2—C367.9 (4)
C12—C13—C20—O12.5 (4)C13—C10—C2—C3−111.1 (3)
C10—C13—C20—O1178.0 (3)C11—C10—C2—C1−113.8 (3)
C12—C13—C20—O2−176.7 (2)C13—C10—C2—C167.2 (4)
C10—C13—C20—O2−1.3 (4)C2—C3—C4—C90.8 (4)
C11—N2—C12—C13−0.3 (3)C2—C3—C4—C5−177.9 (3)
C14—N2—C12—C13177.7 (2)C1—N1—C9—C4−2.8 (4)
C10—C13—C12—N2−0.5 (3)C1—N1—C9—C8177.4 (3)
C20—C13—C12—N2175.8 (2)C3—C4—C9—N12.2 (4)
C9—N1—C1—C20.4 (4)C5—C4—C9—N1−179.1 (3)
C9—N1—C1—Cl1179.1 (2)C3—C4—C9—C8−178.0 (3)
C12—N2—C14—C19153.2 (3)C5—C4—C9—C80.7 (4)
C11—N2—C14—C19−29.2 (4)C9—C4—C5—C6−0.3 (4)
C12—N2—C14—C15−27.3 (4)C3—C4—C5—C6178.4 (3)
C11—N2—C14—C15150.3 (3)C19—C14—C15—C160.9 (5)
C12—C13—C10—C111.1 (3)N2—C14—C15—C16−178.6 (3)
C20—C13—C10—C11−174.9 (2)C17—C16—C15—C140.5 (5)
C12—C13—C10—C2−179.8 (2)C4—C5—C6—C7−0.1 (5)
C20—C13—C10—C24.2 (4)C8—C7—C6—C50.0 (6)
C13—C10—C11—N2−1.2 (3)C6—C7—C8—C90.5 (6)
C2—C10—C11—N2179.6 (2)N1—C9—C8—C7179.0 (3)
C12—N2—C11—C101.0 (3)C4—C9—C8—C7−0.9 (5)
C14—N2—C11—C10−177.0 (2)C15—C14—C19—C18−1.9 (5)
C4—C3—C2—C1−2.9 (4)N2—C14—C19—C18177.6 (3)
C4—C3—C2—C10175.5 (2)C15—C16—C17—C18−1.0 (6)
N1—C1—C2—C32.4 (4)C20—O2—C21—C22139.1 (4)
Cl1—C1—C2—C3−176.30 (19)C16—C17—C18—C190.0 (6)
N1—C1—C2—C10−176.0 (3)C14—C19—C18—C171.5 (6)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C12—H12···O1i0.932.503.383 (3)159
C15—H15···O1i0.932.453.275 (4)148
Symmetry codes: (i) −x+1/2, −y−1/2, −z+1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C12—H12···O1i0.932.503.383 (3)159
C15—H15···O1i0.932.453.275 (4)148
Symmetry codes: (i) −x+1/2, −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 to Professor Salah Rhouati (PHYSYNOR, Université Mentouri Constantine, Algérie) for his assistance. Thanks are due to MESRS (Ministére de l'enseignement supérieur et de la recherche scientifique) for financial support.

references
References top

Belfaitah, A., Ladraa, S., Bouraiou, A., Benali-Cherif, N., Debache, A. & Rhouati, S. (2006). Acta Cryst. E62, o1355–o1357.

Benzerka, S., Bouraiou, A., Debache, A., Rhouati, S. & Belfaitah, A. (2008). J. Soc. Alger. Chim. 18, 71–90.

Bigg, C. H. & Bonnaud, B. (1994). Synthesis, pp. 465–467.

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