supplementary materials


fy2095 scheme

Acta Cryst. (2013). E69, o1127    [ doi:10.1107/S1600536813016541 ]

Ethyl 4-(4-chlorophenyl)-2-methyl-5-oxo-5,6,7,8-tetrahydroquinoline-3-carboxylate

K. Wang, W. Wang, Y. Wang and D. Xu

Abstract top

In the title compound, C19H18ClNO3, the non-aromatic part of the fused ring system adopts an envelope conformation with the central methylene C atom as the flap. The dihedral angle between the pyridine and benzene rings is 56.98 (3)°. In the crystal, molecules are linked into double layers parallel to (100) by a network of weak C-H...O interactions.

Comment top

The pyridine nucleus is of substantial significance as it is the key component in a variety of bioactive compounds, both naturally occurring and synthetic. The oxidative aromatization of 1,4-dihydropyridines is a very convenient approach to the synthesis of highly substituted pyridines (Fang et al., 2007; Mirza-Aghayan et al., 2012). In this article, the title compound was synthesized from the oxidation of the corresponding 1,4-dihydropyridine, and the crystal structure of it is described (Fig. 1). The non-aromatic part of the fused ring is non-planar and adopts an envelope conformation. The α-carbon atom of the carbonyl lies on the same side of the fused ring with the ethyl group, whereas the β-carbon atom of the carbonyl was oriented in opposite direction. The dihedral angle between the pyridine ring and the benzene ring is 56.98 (3)°. In the crystal,molecules are linked by weak C—H···O interactions.

Related literature top

For the synthetic procedure, see: Fang et al. (2007); Mirza-Aghayan et al. (2012). For a related structure, see: Sicheri et al. (1992).

Experimental top

The mixture of 4-chlorobenzaldehyde (1 mmol), ethylacetoacetate (1 mmol) and 3-aminocyclohex-2-enone (1 mmol) was stirred at at 343 K for 3 h (monitored by TLC). Then the mixture was purified by flash column chromatography (silica gel, Hex/AcOEt, v/v, 3:1) giving the 1,4-dihydropyridine compound. The 1,4-dihydropyridine compound was further oxidized by H2O2 (2.0 equiv.) in the presence of the PEG1000-BMImI complex catalyst (50 mol%) to afford the title compound. The pure pruduct is obtained through recrystallation, and single crystals were obtained by slow evaporation of a dichloromethane/n-hexane (1:1 v/v) solution at room temperature.

Refinement top

Methyl H atoms were placed in calculated positions with C—H = 0.96 (1) Å and the torsion was refined to fit the electron density with Uiso(H) = 1.5Ueq(C). Other H atoms were placed in calculated positions and treated as riding atoms: C—H = 0.97 (1) Å (sp3) and C—H = 0.93 Å (aromatic) with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: PROCESS-AUTO (Rigaku, 2006); cell refinement: PROCESS-AUTO (Rigaku, 2006); data reduction: CrystalStructure (Rigaku, 2007); 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, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound. Displacement ellipsoids are drawn at the 40% probability level.
[Figure 2] Fig. 2. Crystal packing of the title compound. H atoms have been omitted for clarity.
Ethyl 4-(4-chlorophenyl)-2-methyl-5-oxo-5,6,7,8-tetrahydroquinoline-3-carboxylate top
Crystal data top
C19H18ClNO3F(000) = 720
Mr = 343.79Dx = 1.337 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 10595 reflections
a = 12.5736 (7) Åθ = 3.1–27.4°
b = 8.3815 (4) ŵ = 0.24 mm1
c = 17.4945 (8) ÅT = 296 K
β = 112.151 (2)°Chunk, yellow
V = 1707.59 (15) Å30.49 × 0.42 × 0.30 mm
Z = 4
Data collection top
Rigaku R-AXIS RAPID
diffractometer
3860 independent reflections
Radiation source: rotating anode2725 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.053
Detector resolution: 10.00 pixels mm-1θmax = 27.5°, θmin = 3.0°
ω scansh = 1616
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
k = 1010
Tmin = 0.891, Tmax = 0.932l = 1822
15658 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.050H-atom parameters constrained
wR(F2) = 0.128 w = 1/[σ2(Fo2) + (0.0515P)2 + 0.6492P]
where P = (Fo2 + 2Fc2)/3
S = 1.00(Δ/σ)max = 0.001
3860 reflectionsΔρmax = 0.28 e Å3
220 parametersΔρmin = 0.26 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.043 (3)
Crystal data top
C19H18ClNO3V = 1707.59 (15) Å3
Mr = 343.79Z = 4
Monoclinic, P21/cMo Kα radiation
a = 12.5736 (7) ŵ = 0.24 mm1
b = 8.3815 (4) ÅT = 296 K
c = 17.4945 (8) Å0.49 × 0.42 × 0.30 mm
β = 112.151 (2)°
Data collection top
Rigaku R-AXIS RAPID
diffractometer
3860 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
2725 reflections with I > 2σ(I)
Tmin = 0.891, Tmax = 0.932Rint = 0.053
15658 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.050H-atom parameters constrained
wR(F2) = 0.128Δρmax = 0.28 e Å3
S = 1.00Δρmin = 0.26 e Å3
3860 reflectionsAbsolute structure: ?
220 parametersAbsolute structure 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
C10.42545 (16)0.6493 (2)0.58924 (11)0.0375 (4)
C20.41107 (17)0.7151 (2)0.51265 (11)0.0413 (4)
C30.50712 (19)0.7626 (2)0.49622 (12)0.0473 (5)
C40.62896 (17)0.6962 (2)0.62798 (12)0.0436 (4)
C50.75005 (18)0.7044 (3)0.69010 (14)0.0580 (6)
H5A0.76730.81420.70800.070*
H5B0.80180.67340.66330.070*
C60.77367 (19)0.6007 (3)0.76517 (14)0.0581 (6)
H6A0.84550.63290.80810.070*
H6B0.78110.49050.75110.070*
C70.67692 (18)0.6145 (3)0.79737 (12)0.0539 (5)
H7A0.69350.54750.84570.065*
H7B0.67070.72400.81320.065*
C80.56577 (17)0.5633 (2)0.73116 (12)0.0426 (4)
C90.53856 (16)0.6381 (2)0.64827 (11)0.0388 (4)
C100.32257 (15)0.6031 (2)0.60723 (11)0.0368 (4)
C110.30200 (17)0.6742 (2)0.67217 (11)0.0426 (4)
H110.35450.74750.70560.051*
C120.20518 (18)0.6381 (2)0.68790 (12)0.0466 (5)
H120.19220.68620.73150.056*
C130.12768 (16)0.5288 (2)0.63758 (12)0.0434 (4)
C140.14541 (17)0.4562 (2)0.57310 (12)0.0461 (5)
H140.09250.38290.54000.055*
C150.24351 (16)0.4933 (2)0.55776 (11)0.0426 (4)
H150.25620.44450.51420.051*
C160.29397 (18)0.7489 (2)0.44907 (11)0.0454 (5)
C170.1340 (2)0.9227 (3)0.41726 (18)0.0778 (8)
H17A0.07570.84300.41170.093*
H17B0.13650.94180.36330.093*
C180.1069 (2)1.0718 (3)0.4508 (2)0.0846 (8)
H18A0.10201.05080.50330.127*
H18B0.03481.11290.41340.127*
H18C0.16631.14880.45760.127*
C190.4969 (2)0.8326 (3)0.41431 (14)0.0654 (6)
H19A0.56310.89710.42160.098*
H19B0.42900.89740.39300.098*
H19C0.49200.74800.37610.098*
Cl10.00542 (5)0.48132 (7)0.65772 (4)0.0647 (2)
N10.61354 (15)0.7536 (2)0.55298 (11)0.0497 (4)
O10.50420 (13)0.46307 (17)0.74340 (9)0.0545 (4)
O20.24504 (13)0.86760 (17)0.47419 (9)0.0560 (4)
O30.25193 (14)0.68423 (19)0.38335 (9)0.0642 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0394 (10)0.0356 (9)0.0393 (10)0.0022 (7)0.0169 (8)0.0045 (7)
C20.0432 (11)0.0426 (10)0.0390 (10)0.0019 (8)0.0166 (8)0.0033 (7)
C30.0537 (13)0.0487 (11)0.0459 (11)0.0031 (9)0.0262 (10)0.0020 (8)
C40.0394 (11)0.0446 (10)0.0500 (11)0.0014 (8)0.0205 (9)0.0058 (8)
C50.0382 (12)0.0722 (14)0.0639 (14)0.0048 (10)0.0196 (10)0.0048 (11)
C60.0400 (12)0.0701 (14)0.0582 (13)0.0018 (10)0.0117 (10)0.0068 (10)
C70.0464 (12)0.0677 (13)0.0432 (11)0.0007 (10)0.0117 (9)0.0050 (9)
C80.0390 (10)0.0466 (10)0.0423 (10)0.0047 (8)0.0155 (8)0.0018 (8)
C90.0383 (10)0.0395 (9)0.0397 (10)0.0003 (7)0.0161 (8)0.0045 (7)
C100.0337 (9)0.0383 (9)0.0365 (9)0.0006 (7)0.0111 (7)0.0014 (7)
C110.0406 (11)0.0461 (10)0.0408 (10)0.0086 (8)0.0149 (8)0.0091 (8)
C120.0471 (12)0.0515 (11)0.0461 (11)0.0019 (8)0.0231 (9)0.0066 (8)
C130.0330 (10)0.0481 (10)0.0501 (11)0.0007 (8)0.0168 (8)0.0036 (8)
C140.0376 (11)0.0476 (10)0.0492 (11)0.0089 (8)0.0117 (9)0.0075 (8)
C150.0410 (11)0.0470 (10)0.0394 (10)0.0026 (8)0.0148 (8)0.0067 (7)
C160.0505 (12)0.0481 (10)0.0382 (10)0.0041 (9)0.0173 (9)0.0018 (8)
C170.0601 (16)0.0666 (15)0.0816 (18)0.0133 (12)0.0019 (13)0.0026 (13)
C180.0680 (18)0.0735 (17)0.112 (2)0.0162 (13)0.0335 (17)0.0057 (16)
C190.0703 (16)0.0826 (16)0.0528 (13)0.0089 (12)0.0341 (12)0.0065 (11)
Cl10.0444 (3)0.0791 (4)0.0791 (4)0.0094 (3)0.0330 (3)0.0020 (3)
N10.0463 (10)0.0581 (10)0.0523 (10)0.0038 (8)0.0271 (8)0.0016 (8)
O10.0472 (9)0.0600 (9)0.0539 (9)0.0002 (7)0.0163 (7)0.0149 (7)
O20.0498 (9)0.0548 (8)0.0536 (9)0.0088 (6)0.0084 (7)0.0054 (6)
O30.0649 (11)0.0769 (10)0.0418 (8)0.0010 (8)0.0100 (7)0.0117 (7)
Geometric parameters (Å, º) top
C1—C21.396 (3)C10—C111.391 (3)
C1—C91.411 (3)C11—C121.379 (3)
C1—C101.493 (3)C11—H110.9300
C2—C31.400 (3)C12—C131.385 (3)
C2—C161.500 (3)C12—H120.9300
C3—N11.334 (3)C13—C141.372 (3)
C3—C191.509 (3)C13—Cl11.748 (2)
C4—N11.341 (3)C14—C151.393 (3)
C4—C91.400 (3)C14—H140.9300
C4—C51.502 (3)C15—H150.9300
C5—C61.508 (3)C16—O31.199 (2)
C5—H5A0.9700C16—O21.329 (2)
C5—H5B0.9700C17—O21.451 (3)
C6—C71.525 (3)C17—C181.474 (4)
C6—H6A0.9700C17—H17A0.9700
C6—H6B0.9700C17—H17B0.9700
C7—C81.503 (3)C18—H18A0.9600
C7—H7A0.9700C18—H18B0.9600
C7—H7B0.9700C18—H18C0.9600
C8—O11.215 (2)C19—H19A0.9600
C8—C91.496 (3)C19—H19B0.9600
C10—C151.391 (2)C19—H19C0.9600
C2—C1—C9117.32 (17)C12—C11—C10121.26 (17)
C2—C1—C10119.73 (16)C12—C11—H11119.4
C9—C1—C10122.86 (16)C10—C11—H11119.4
C1—C2—C3119.96 (18)C11—C12—C13118.74 (18)
C1—C2—C16121.46 (17)C11—C12—H12120.6
C3—C2—C16118.39 (17)C13—C12—H12120.6
N1—C3—C2122.12 (18)C14—C13—C12121.52 (18)
N1—C3—C19115.56 (19)C14—C13—Cl1119.53 (15)
C2—C3—C19122.3 (2)C12—C13—Cl1118.95 (15)
N1—C4—C9122.76 (18)C13—C14—C15119.31 (17)
N1—C4—C5115.12 (18)C13—C14—H14120.3
C9—C4—C5122.07 (18)C15—C14—H14120.3
C4—C5—C6114.62 (18)C10—C15—C14120.33 (17)
C4—C5—H5A108.6C10—C15—H15119.8
C6—C5—H5A108.6C14—C15—H15119.8
C4—C5—H5B108.6O3—C16—O2124.34 (19)
C6—C5—H5B108.6O3—C16—C2125.48 (19)
H5A—C5—H5B107.6O2—C16—C2110.09 (16)
C5—C6—C7110.81 (18)O2—C17—C18107.7 (2)
C5—C6—H6A109.5O2—C17—H17A110.2
C7—C6—H6A109.5C18—C17—H17A110.2
C5—C6—H6B109.5O2—C17—H17B110.2
C7—C6—H6B109.5C18—C17—H17B110.2
H6A—C6—H6B108.1H17A—C17—H17B108.5
C8—C7—C6109.46 (17)C17—C18—H18A109.5
C8—C7—H7A109.8C17—C18—H18B109.5
C6—C7—H7A109.8H18A—C18—H18B109.5
C8—C7—H7B109.8C17—C18—H18C109.5
C6—C7—H7B109.8H18A—C18—H18C109.5
H7A—C7—H7B108.2H18B—C18—H18C109.5
O1—C8—C9122.17 (17)C3—C19—H19A109.5
O1—C8—C7122.06 (18)C3—C19—H19B109.5
C9—C8—C7115.71 (17)H19A—C19—H19B109.5
C4—C9—C1118.81 (17)C3—C19—H19C109.5
C4—C9—C8118.73 (17)H19A—C19—H19C109.5
C1—C9—C8122.44 (17)H19B—C19—H19C109.5
C15—C10—C11118.84 (17)C3—N1—C4118.87 (17)
C15—C10—C1120.88 (16)C16—O2—C17117.20 (17)
C11—C10—C1120.24 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6B···O3i0.972.673.454 (3)139
C11—H11···O1ii0.932.453.357 (2)164
C12—H12···O3iii0.932.703.569 (2)156
Symmetry codes: (i) x+1, y+1, z+1; (ii) x+1, y+1/2, z+3/2; (iii) x, y+3/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC19H18ClNO3
Mr343.79
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)12.5736 (7), 8.3815 (4), 17.4945 (8)
β (°) 112.151 (2)
V3)1707.59 (15)
Z4
Radiation typeMo Kα
µ (mm1)0.24
Crystal size (mm)0.49 × 0.42 × 0.30
Data collection
DiffractometerRigaku R-AXIS RAPID
diffractometer
Absorption correctionMulti-scan
(ABSCOR; Higashi, 1995)
Tmin, Tmax0.891, 0.932
No. of measured, independent and
observed [I > 2σ(I)] reflections
15658, 3860, 2725
Rint0.053
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.050, 0.128, 1.00
No. of reflections3860
No. of parameters220
No. of restraints0
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.28, 0.26

Computer programs: PROCESS-AUTO (Rigaku, 2006), CrystalStructure (Rigaku, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), WinGX (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6B···O3i0.972.6673.454 (3)139
C11—H11···O1ii0.932.4543.357 (2)164
C12—H12···O3iii0.932.7013.569 (2)156
Symmetry codes: (i) x+1, y+1, z+1; (ii) x+1, y+1/2, z+3/2; (iii) x, y+3/2, z+1/2.
Acknowledgements top

This work was supported by the Zhejiang Provincial Natural Science Foundation of China (No. Y4110373). We are also grateful for the help of Professor Jian-Ming Gu of Zhejiang University.

references
References top

Fang, X., Liu, Y.-C. & Li, C. (2007). J. Org. Chem. 72, 8608–8610.

Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854.

Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.

Mirza-Aghayan, M., Boukherroub, R., Nemati, M. & Rahimifard, M. (2012). Tetrahedron Lett. 53, 2473–2475.

Rigaku (2006). PROCESS-AUTO. Rigaku Corporation, Tokyo, Japan.

Rigaku (2007). CrystalStructure. Rigaku Americas, The Woodlands, Texas, USA.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.

Sicheri, F. V., Derry, W. B., Gupta, R. S. & Yang, D. S.-C. (1992). Acta Cryst. C48, 1687–1689.