organic compounds
Ethyl 4-(4-chlorophenyl)-2-methyl-5-oxo-5,6,7,8-tetrahydroquinoline-3-carboxylate
aCatalytic Hydrogenation Research Center, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China, and bZhejiang Huanke Environment Consultancy Co.,Ltd, No. 111 Tianmushan Road, Hangzhou 310007, People's Republic of China
*Correspondence e-mail: chrc@zjut.edu.cn
In the title compound, C19H18ClNO3, the non-aromatic part of the fused ring system adopts an 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.
Related literature
For the synthetic procedure, see: Fang et al. (2007); Mirza-Aghayan et al. (2012). For a related structure, see: Sicheri et al. (1992).
Experimental
Crystal data
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Data collection: PROCESS-AUTO (Rigaku, 2006); cell PROCESS-AUTO; 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).
Supporting information
https://doi.org/10.1107/S1600536813016541/fy2095sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536813016541/fy2095Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S1600536813016541/fy2095Isup3.cml
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
(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.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).
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 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.
of it is described (Fig. 1). The non-aromatic part of the fused ring is non-planar and adopts an TheFor the synthetic procedure, see: Fang et al. (2007); Mirza-Aghayan et al. (2012). For a related structure, see: Sicheri et al. (1992).
Data collection: PROCESS-AUTO (Rigaku, 2006); cell
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).C19H18ClNO3 | F(000) = 720 |
Mr = 343.79 | Dx = 1.337 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 10595 reflections |
a = 12.5736 (7) Å | θ = 3.1–27.4° |
b = 8.3815 (4) Å | µ = 0.24 mm−1 |
c = 17.4945 (8) Å | T = 296 K |
β = 112.151 (2)° | Chunk, yellow |
V = 1707.59 (15) Å3 | 0.49 × 0.42 × 0.30 mm |
Z = 4 |
Rigaku R-AXIS RAPID diffractometer | 3860 independent reflections |
Radiation source: rotating anode | 2725 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.053 |
Detector resolution: 10.00 pixels mm-1 | θmax = 27.5°, θmin = 3.0° |
ω scans | h = −16→16 |
Absorption correction: multi-scan (ABSCOR; Higashi, 1995) | k = −10→10 |
Tmin = 0.891, Tmax = 0.932 | l = −18→22 |
15658 measured reflections |
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)] = 0.050 | H-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 reflections | Δρmax = 0.28 e Å−3 |
220 parameters | Δρmin = −0.26 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.043 (3) |
C19H18ClNO3 | V = 1707.59 (15) Å3 |
Mr = 343.79 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 12.5736 (7) Å | µ = 0.24 mm−1 |
b = 8.3815 (4) Å | T = 296 K |
c = 17.4945 (8) Å | 0.49 × 0.42 × 0.30 mm |
β = 112.151 (2)° |
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 = 0.932 | Rint = 0.053 |
15658 measured reflections |
R[F2 > 2σ(F2)] = 0.050 | 0 restraints |
wR(F2) = 0.128 | H-atom parameters constrained |
S = 1.00 | Δρmax = 0.28 e Å−3 |
3860 reflections | Δρmin = −0.26 e Å−3 |
220 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.42545 (16) | 0.6493 (2) | 0.58924 (11) | 0.0375 (4) | |
C2 | 0.41107 (17) | 0.7151 (2) | 0.51265 (11) | 0.0413 (4) | |
C3 | 0.50712 (19) | 0.7626 (2) | 0.49622 (12) | 0.0473 (5) | |
C4 | 0.62896 (17) | 0.6962 (2) | 0.62798 (12) | 0.0436 (4) | |
C5 | 0.75005 (18) | 0.7044 (3) | 0.69010 (14) | 0.0580 (6) | |
H5A | 0.7673 | 0.8142 | 0.7080 | 0.070* | |
H5B | 0.8018 | 0.6734 | 0.6633 | 0.070* | |
C6 | 0.77367 (19) | 0.6007 (3) | 0.76517 (14) | 0.0581 (6) | |
H6A | 0.8455 | 0.6329 | 0.8081 | 0.070* | |
H6B | 0.7811 | 0.4905 | 0.7511 | 0.070* | |
C7 | 0.67692 (18) | 0.6145 (3) | 0.79737 (12) | 0.0539 (5) | |
H7A | 0.6935 | 0.5475 | 0.8457 | 0.065* | |
H7B | 0.6707 | 0.7240 | 0.8132 | 0.065* | |
C8 | 0.56577 (17) | 0.5633 (2) | 0.73116 (12) | 0.0426 (4) | |
C9 | 0.53856 (16) | 0.6381 (2) | 0.64827 (11) | 0.0388 (4) | |
C10 | 0.32257 (15) | 0.6031 (2) | 0.60723 (11) | 0.0368 (4) | |
C11 | 0.30200 (17) | 0.6742 (2) | 0.67217 (11) | 0.0426 (4) | |
H11 | 0.3545 | 0.7475 | 0.7056 | 0.051* | |
C12 | 0.20518 (18) | 0.6381 (2) | 0.68790 (12) | 0.0466 (5) | |
H12 | 0.1922 | 0.6862 | 0.7315 | 0.056* | |
C13 | 0.12768 (16) | 0.5288 (2) | 0.63758 (12) | 0.0434 (4) | |
C14 | 0.14541 (17) | 0.4562 (2) | 0.57310 (12) | 0.0461 (5) | |
H14 | 0.0925 | 0.3829 | 0.5400 | 0.055* | |
C15 | 0.24351 (16) | 0.4933 (2) | 0.55776 (11) | 0.0426 (4) | |
H15 | 0.2562 | 0.4445 | 0.5142 | 0.051* | |
C16 | 0.29397 (18) | 0.7489 (2) | 0.44907 (11) | 0.0454 (5) | |
C17 | 0.1340 (2) | 0.9227 (3) | 0.41726 (18) | 0.0778 (8) | |
H17A | 0.0757 | 0.8430 | 0.4117 | 0.093* | |
H17B | 0.1365 | 0.9418 | 0.3633 | 0.093* | |
C18 | 0.1069 (2) | 1.0718 (3) | 0.4508 (2) | 0.0846 (8) | |
H18A | 0.1020 | 1.0508 | 0.5033 | 0.127* | |
H18B | 0.0348 | 1.1129 | 0.4134 | 0.127* | |
H18C | 0.1663 | 1.1488 | 0.4576 | 0.127* | |
C19 | 0.4969 (2) | 0.8326 (3) | 0.41431 (14) | 0.0654 (6) | |
H19A | 0.5631 | 0.8971 | 0.4216 | 0.098* | |
H19B | 0.4290 | 0.8974 | 0.3930 | 0.098* | |
H19C | 0.4920 | 0.7480 | 0.3761 | 0.098* | |
Cl1 | 0.00542 (5) | 0.48132 (7) | 0.65772 (4) | 0.0647 (2) | |
N1 | 0.61354 (15) | 0.7536 (2) | 0.55298 (11) | 0.0497 (4) | |
O1 | 0.50420 (13) | 0.46307 (17) | 0.74340 (9) | 0.0545 (4) | |
O2 | 0.24504 (13) | 0.86760 (17) | 0.47419 (9) | 0.0560 (4) | |
O3 | 0.25193 (14) | 0.68423 (19) | 0.38335 (9) | 0.0642 (5) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0394 (10) | 0.0356 (9) | 0.0393 (10) | −0.0022 (7) | 0.0169 (8) | −0.0045 (7) |
C2 | 0.0432 (11) | 0.0426 (10) | 0.0390 (10) | −0.0019 (8) | 0.0166 (8) | −0.0033 (7) |
C3 | 0.0537 (13) | 0.0487 (11) | 0.0459 (11) | −0.0031 (9) | 0.0262 (10) | −0.0020 (8) |
C4 | 0.0394 (11) | 0.0446 (10) | 0.0500 (11) | −0.0014 (8) | 0.0205 (9) | −0.0058 (8) |
C5 | 0.0382 (12) | 0.0722 (14) | 0.0639 (14) | −0.0048 (10) | 0.0196 (10) | −0.0048 (11) |
C6 | 0.0400 (12) | 0.0701 (14) | 0.0582 (13) | 0.0018 (10) | 0.0117 (10) | −0.0068 (10) |
C7 | 0.0464 (12) | 0.0677 (13) | 0.0432 (11) | −0.0007 (10) | 0.0117 (9) | −0.0050 (9) |
C8 | 0.0390 (10) | 0.0466 (10) | 0.0423 (10) | 0.0047 (8) | 0.0155 (8) | −0.0018 (8) |
C9 | 0.0383 (10) | 0.0395 (9) | 0.0397 (10) | −0.0003 (7) | 0.0161 (8) | −0.0045 (7) |
C10 | 0.0337 (9) | 0.0383 (9) | 0.0365 (9) | −0.0006 (7) | 0.0111 (7) | 0.0014 (7) |
C11 | 0.0406 (11) | 0.0461 (10) | 0.0408 (10) | −0.0086 (8) | 0.0149 (8) | −0.0091 (8) |
C12 | 0.0471 (12) | 0.0515 (11) | 0.0461 (11) | −0.0019 (8) | 0.0231 (9) | −0.0066 (8) |
C13 | 0.0330 (10) | 0.0481 (10) | 0.0501 (11) | −0.0007 (8) | 0.0168 (8) | 0.0036 (8) |
C14 | 0.0376 (11) | 0.0476 (10) | 0.0492 (11) | −0.0089 (8) | 0.0117 (9) | −0.0075 (8) |
C15 | 0.0410 (11) | 0.0470 (10) | 0.0394 (10) | −0.0026 (8) | 0.0148 (8) | −0.0067 (7) |
C16 | 0.0505 (12) | 0.0481 (10) | 0.0382 (10) | −0.0041 (9) | 0.0173 (9) | 0.0018 (8) |
C17 | 0.0601 (16) | 0.0666 (15) | 0.0816 (18) | 0.0133 (12) | −0.0019 (13) | −0.0026 (13) |
C18 | 0.0680 (18) | 0.0735 (17) | 0.112 (2) | 0.0162 (13) | 0.0335 (17) | 0.0057 (16) |
C19 | 0.0703 (16) | 0.0826 (16) | 0.0528 (13) | −0.0089 (12) | 0.0341 (12) | 0.0065 (11) |
Cl1 | 0.0444 (3) | 0.0791 (4) | 0.0791 (4) | −0.0094 (3) | 0.0330 (3) | −0.0020 (3) |
N1 | 0.0463 (10) | 0.0581 (10) | 0.0523 (10) | −0.0038 (8) | 0.0271 (8) | −0.0016 (8) |
O1 | 0.0472 (9) | 0.0600 (9) | 0.0539 (9) | −0.0002 (7) | 0.0163 (7) | 0.0149 (7) |
O2 | 0.0498 (9) | 0.0548 (8) | 0.0536 (9) | 0.0088 (6) | 0.0084 (7) | −0.0054 (6) |
O3 | 0.0649 (11) | 0.0769 (10) | 0.0418 (8) | 0.0010 (8) | 0.0100 (7) | −0.0117 (7) |
C1—C2 | 1.396 (3) | C10—C11 | 1.391 (3) |
C1—C9 | 1.411 (3) | C11—C12 | 1.379 (3) |
C1—C10 | 1.493 (3) | C11—H11 | 0.9300 |
C2—C3 | 1.400 (3) | C12—C13 | 1.385 (3) |
C2—C16 | 1.500 (3) | C12—H12 | 0.9300 |
C3—N1 | 1.334 (3) | C13—C14 | 1.372 (3) |
C3—C19 | 1.509 (3) | C13—Cl1 | 1.748 (2) |
C4—N1 | 1.341 (3) | C14—C15 | 1.393 (3) |
C4—C9 | 1.400 (3) | C14—H14 | 0.9300 |
C4—C5 | 1.502 (3) | C15—H15 | 0.9300 |
C5—C6 | 1.508 (3) | C16—O3 | 1.199 (2) |
C5—H5A | 0.9700 | C16—O2 | 1.329 (2) |
C5—H5B | 0.9700 | C17—O2 | 1.451 (3) |
C6—C7 | 1.525 (3) | C17—C18 | 1.474 (4) |
C6—H6A | 0.9700 | C17—H17A | 0.9700 |
C6—H6B | 0.9700 | C17—H17B | 0.9700 |
C7—C8 | 1.503 (3) | C18—H18A | 0.9600 |
C7—H7A | 0.9700 | C18—H18B | 0.9600 |
C7—H7B | 0.9700 | C18—H18C | 0.9600 |
C8—O1 | 1.215 (2) | C19—H19A | 0.9600 |
C8—C9 | 1.496 (3) | C19—H19B | 0.9600 |
C10—C15 | 1.391 (2) | C19—H19C | 0.9600 |
C2—C1—C9 | 117.32 (17) | C12—C11—C10 | 121.26 (17) |
C2—C1—C10 | 119.73 (16) | C12—C11—H11 | 119.4 |
C9—C1—C10 | 122.86 (16) | C10—C11—H11 | 119.4 |
C1—C2—C3 | 119.96 (18) | C11—C12—C13 | 118.74 (18) |
C1—C2—C16 | 121.46 (17) | C11—C12—H12 | 120.6 |
C3—C2—C16 | 118.39 (17) | C13—C12—H12 | 120.6 |
N1—C3—C2 | 122.12 (18) | C14—C13—C12 | 121.52 (18) |
N1—C3—C19 | 115.56 (19) | C14—C13—Cl1 | 119.53 (15) |
C2—C3—C19 | 122.3 (2) | C12—C13—Cl1 | 118.95 (15) |
N1—C4—C9 | 122.76 (18) | C13—C14—C15 | 119.31 (17) |
N1—C4—C5 | 115.12 (18) | C13—C14—H14 | 120.3 |
C9—C4—C5 | 122.07 (18) | C15—C14—H14 | 120.3 |
C4—C5—C6 | 114.62 (18) | C10—C15—C14 | 120.33 (17) |
C4—C5—H5A | 108.6 | C10—C15—H15 | 119.8 |
C6—C5—H5A | 108.6 | C14—C15—H15 | 119.8 |
C4—C5—H5B | 108.6 | O3—C16—O2 | 124.34 (19) |
C6—C5—H5B | 108.6 | O3—C16—C2 | 125.48 (19) |
H5A—C5—H5B | 107.6 | O2—C16—C2 | 110.09 (16) |
C5—C6—C7 | 110.81 (18) | O2—C17—C18 | 107.7 (2) |
C5—C6—H6A | 109.5 | O2—C17—H17A | 110.2 |
C7—C6—H6A | 109.5 | C18—C17—H17A | 110.2 |
C5—C6—H6B | 109.5 | O2—C17—H17B | 110.2 |
C7—C6—H6B | 109.5 | C18—C17—H17B | 110.2 |
H6A—C6—H6B | 108.1 | H17A—C17—H17B | 108.5 |
C8—C7—C6 | 109.46 (17) | C17—C18—H18A | 109.5 |
C8—C7—H7A | 109.8 | C17—C18—H18B | 109.5 |
C6—C7—H7A | 109.8 | H18A—C18—H18B | 109.5 |
C8—C7—H7B | 109.8 | C17—C18—H18C | 109.5 |
C6—C7—H7B | 109.8 | H18A—C18—H18C | 109.5 |
H7A—C7—H7B | 108.2 | H18B—C18—H18C | 109.5 |
O1—C8—C9 | 122.17 (17) | C3—C19—H19A | 109.5 |
O1—C8—C7 | 122.06 (18) | C3—C19—H19B | 109.5 |
C9—C8—C7 | 115.71 (17) | H19A—C19—H19B | 109.5 |
C4—C9—C1 | 118.81 (17) | C3—C19—H19C | 109.5 |
C4—C9—C8 | 118.73 (17) | H19A—C19—H19C | 109.5 |
C1—C9—C8 | 122.44 (17) | H19B—C19—H19C | 109.5 |
C15—C10—C11 | 118.84 (17) | C3—N1—C4 | 118.87 (17) |
C15—C10—C1 | 120.88 (16) | C16—O2—C17 | 117.20 (17) |
C11—C10—C1 | 120.24 (16) |
D—H···A | D—H | H···A | D···A | D—H···A |
C6—H6B···O3i | 0.97 | 2.67 | 3.454 (3) | 139 |
C11—H11···O1ii | 0.93 | 2.45 | 3.357 (2) | 164 |
C12—H12···O3iii | 0.93 | 2.70 | 3.569 (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 formula | C19H18ClNO3 |
Mr | 343.79 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 296 |
a, b, c (Å) | 12.5736 (7), 8.3815 (4), 17.4945 (8) |
β (°) | 112.151 (2) |
V (Å3) | 1707.59 (15) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.24 |
Crystal size (mm) | 0.49 × 0.42 × 0.30 |
Data collection | |
Diffractometer | Rigaku R-AXIS RAPID |
Absorption correction | Multi-scan (ABSCOR; Higashi, 1995) |
Tmin, Tmax | 0.891, 0.932 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 15658, 3860, 2725 |
Rint | 0.053 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.050, 0.128, 1.00 |
No. of reflections | 3860 |
No. of parameters | 220 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 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).
D—H···A | D—H | H···A | D···A | D—H···A |
C6—H6B···O3i | 0.97 | 2.667 | 3.454 (3) | 139 |
C11—H11···O1ii | 0.93 | 2.454 | 3.357 (2) | 164 |
C12—H12···O3iii | 0.93 | 2.701 | 3.569 (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
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
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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.