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ISSN: 2056-9890

Ethyl 2-methyl-4-phenyl­quinoline-3-carboxyl­ate

aDepartment of Chemistry, Islamic Azad University, Dorood Branch, Dorood 688173551, Iran
*Correspondence e-mail: a_bazgir@yahoo.com

(Received 3 May 2009; accepted 17 May 2009; online 23 May 2009)

In the mol­ecule of the title compound, C19H17NO2, the quinoline ring system is planar [maximum deviation 0.021 (3) Å] and oriented with respect to the phenyl ring at a dihedral angle of 80.44 (4)°. Intra­molecular C—H⋯O inter­actions result in the formation of five- and six-membered rings having planar and envelope conformations, respectively. In the crystal structure, inter­molecular C—H⋯O inter­actions link the mol­ecules into centrosymmetric dimers forming R22(12) ring motifs. ππ contacts between the rings of the quinoline system [centroid-to-centroid distance = 3.812 (1) Å] may further stabilize the structure. Two weak C—H⋯π inter­actions are also found.

Related literature

For general background, see: Doube et al. (1998[Doube, D., Blouin, M., Brideau, C., Chan, C., Desmarais, S., Eithier, D., Falgueyert, J. P., Freisen, R. W., Girrard, M., Girrard, J., Tagari, P. & Yang, R. N. (1998). Bioorg. Med. Chem. Lett. 8, 1255-1260.]). For ring-motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C19H17NO2

  • Mr = 291.34

  • Triclinic, [P \overline 1]

  • a = 9.0282 (10) Å

  • b = 9.362 (1) Å

  • c = 10.7258 (10) Å

  • α = 69.765 (8)°

  • β = 66.733 (8)°

  • γ = 70.605 (8)°

  • V = 761.08 (15) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 120 K

  • 0.35 × 0.32 × 0.25 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: none

  • 8164 measured reflections

  • 3995 independent reflections

  • 3410 reflections with I > 2σ(I)

  • Rint = 0.044

Refinement
  • R[F2 > 2σ(F2)] = 0.065

  • wR(F2) = 0.194

  • S = 1.09

  • 3995 reflections

  • 199 parameters

  • H-atom parameters constrained

  • Δρmax = 0.33 e Å−3

  • Δρmin = −0.35 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C16—H16A⋯O1 0.97 2.32 2.711 (3) 103
C19—H19B⋯O2i 0.96 2.52 3.374 (3) 147
C19—H19C⋯O2 0.96 2.59 3.212 (3) 122
C12—H12⋯Cg2ii 0.93 2.95 3.750 (3) 145
C17—H17CCg3iii 0.96 2.97 3.883 (3) 160
Symmetry codes: (i) -x+1, -y-2, -z+1; (ii) -x+2, -y, -z+1; (iii) -x+2, -y, -z. Cg2 and Cg3 are the centroids of rings C1–C6 and C8–C13, respectively.

Data collection: SMART (Bruker, 1998[Bruker (1998). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 1998[Bruker (1998). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information


Comment top

The quinoline moiety is probably the most well known heterocycle, a common and important feature of a variety of natural products and medicinal agents. They have emerged as antimalarial, antiasthmatic, anti-inflamatory, antibacterial, antihypertensive and tyrosine kinase PDGF-RTK inhibiting agents (Doube et al., 1998). Moreover, polyquinolines are found to undergo hierarchical self-assembly into a variety of nano and meso structures with enhanced electronic and photonic functions. We report herein the synthesis and crystal structure of the title compound.

In the molecule of the title compound (Fig. 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. The quinoline ring system A (N1/C1–C7/C14/C18) is planar with a maximum deviaton of -0.021 (3) Å for atom C18, and oriented with respect to the phenyl ring B (C8–C13) at a dihedral angle of A/B = 80.44 (4)°. Intramolecular C—H···O interactions result in the formations of five- and six-membered rings C (O1/O2/C15/C16/H16A) and D (O2/C14/C15/C18/C19/H19C). Ring C is planar, while ring D adopts envelope conformation, with atom O2 displaced by -1.166 (4) Å from the plane of the other ring atoms.

In the crystal structure, intermolecular C—H···O interactions (Table 1) link the molecules into centrosymmetric dimers forming R22(12) ring motifs (Fig. 2) (Bernstein et al., 1995), in which they may be effective in the stabilization of the structure. The ππ contact between the rings of the quinoline ring system, Cg1···Cg2i [symmetry code: (i) 1 - x, -1 - y, 1 - z, where Cg1 and Cg2 are centroids of the rings (N1/C1/C6/C7/C14/C18) and (C1–C6), respectively] may further stabilize the structure, with centroid-centroid distance of 3.812 (1) Å. There also exist two weak C—H···π interactions (Table 1).

Related literature top

For general background, see: Doube et al. (1998). For ring-motifs, see: Bernstein et al. (1995). For bond-length data, see: Allen et al. (1987).

Experimental top

For the preparation of the title compound, a mixture of ethyl acetoacetate (0.13 g, 1 mmol), (2-aminophenyl)(phenyl)methanone (0.20 g, 1 mmol) and p-toluene sulfonic acid (0.1 g, 5.8 mmol) in water (5 ml) was stirred at reflux for 4 h. After completion of reaction (monitored by TLC) the reaction mixture was filtered and the precipitate washed with water (15 ml) and then recrystallized from EtOH/water (1:2) to afford the pure product (yield; 75%, 0.218 g).

Refinement top

H atoms were positioned geometrically, with C—H = 0.93, 0.97 and 0.96 Å for aromatic, methylene and methyl H, respectively, and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Hydrogen bonds are shown as dotted lines.
[Figure 2] Fig. 2. A partial packing diagram of the title compound. Hydrogen bonds are shown as dashed lines.
Ethyl 2-methyl-4-phenylquinoline-3-carboxylate top
Crystal data top
C19H17NO2Z = 2
Mr = 291.34F(000) = 308
Triclinic, P1Dx = 1.271 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 9.0282 (10) ÅCell parameters from 1548 reflections
b = 9.362 (1) Åθ = 2.4–29.2°
c = 10.7258 (10) ŵ = 0.08 mm1
α = 69.765 (8)°T = 120 K
β = 66.733 (8)°Block, colourless
γ = 70.605 (8)°0.35 × 0.32 × 0.25 mm
V = 761.08 (15) Å3
Data collection top
Bruker SMART CCD area-detector
diffractometer
Rint = 0.044
ϕ and ω scansθmax = 29.2°, θmin = 2.4°
8164 measured reflectionsh = 1212
3995 independent reflectionsk = 1212
3410 reflections with I > 2σ(I)l = 1314
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.065 w = 1/[σ2(Fo2) + (0.0955P)2 + 0.1587P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.194(Δ/σ)max = 0.01
S = 1.09Δρmax = 0.33 e Å3
3995 reflectionsΔρmin = 0.35 e Å3
199 parameters
Crystal data top
C19H17NO2γ = 70.605 (8)°
Mr = 291.34V = 761.08 (15) Å3
Triclinic, P1Z = 2
a = 9.0282 (10) ÅMo Kα radiation
b = 9.362 (1) ŵ = 0.08 mm1
c = 10.7258 (10) ÅT = 120 K
α = 69.765 (8)°0.35 × 0.32 × 0.25 mm
β = 66.733 (8)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
3410 reflections with I > 2σ(I)
8164 measured reflectionsRint = 0.044
3995 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0650 restraints
wR(F2) = 0.194H-atom parameters constrained
S = 1.09Δρmax = 0.33 e Å3
3995 reflectionsΔρmin = 0.35 e Å3
199 parameters
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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.6903 (3)0.70878 (17)0.11893 (14)0.0879 (5)
O20.6965 (2)0.95151 (14)0.24871 (13)0.0696 (4)
N10.44256 (15)0.71135 (15)0.57975 (13)0.0470 (3)
C10.56342 (18)0.68228 (16)0.60840 (15)0.0438 (3)
C20.5192 (2)0.6418 (2)0.73600 (17)0.0551 (4)
H20.41040.63280.79530.066*
C30.6347 (3)0.6159 (2)0.77284 (19)0.0622 (5)
H30.60460.59070.85750.075*
C40.7988 (2)0.6273 (2)0.6834 (2)0.0615 (4)
H40.87670.60960.70940.074*
C50.8456 (2)0.66413 (19)0.55808 (18)0.0523 (4)
H50.95450.67020.49940.063*
C60.72854 (17)0.69295 (15)0.51769 (15)0.0420 (3)
C70.76870 (17)0.73393 (15)0.38991 (14)0.0402 (3)
C80.94211 (17)0.75008 (16)0.29187 (15)0.0423 (3)
C91.0023 (2)0.61966 (19)0.20110 (18)0.0546 (4)
H90.93260.52060.19850.066*
C101.1658 (2)0.6361 (2)0.11427 (19)0.0619 (4)
H101.20490.54830.05350.074*
C111.2697 (2)0.7819 (2)0.11829 (18)0.0612 (5)
H111.37960.79250.06140.073*
C121.2116 (2)0.9125 (2)0.20633 (19)0.0622 (4)
H121.28181.01120.20810.075*
C131.0480 (2)0.89658 (18)0.29248 (17)0.0526 (4)
H131.0090.98510.35120.063*
C140.64476 (17)0.76184 (16)0.36344 (14)0.0410 (3)
C150.67936 (18)0.80112 (17)0.22859 (15)0.0451 (3)
C160.7336 (3)1.0130 (2)0.12943 (19)0.0640 (5)
H16A0.75940.93310.04280.077*
H16B0.63891.04610.13650.077*
C170.8780 (3)1.1482 (3)0.1307 (2)0.0694 (5)
H17A0.85111.22650.21680.083*
H17B0.97111.1140.12310.083*
H17C0.9051.19130.05320.083*
C180.48148 (18)0.75086 (17)0.46289 (15)0.0441 (3)
C190.3470 (2)0.7867 (2)0.43737 (19)0.0577 (4)
H19A0.25670.69650.43560.069*
H19B0.30860.87270.5110.069*
H19C0.38970.81380.34910.069*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.1583 (17)0.0598 (8)0.0463 (7)0.0329 (9)0.0344 (9)0.0036 (6)
O20.1184 (12)0.0481 (6)0.0487 (6)0.0242 (7)0.0284 (7)0.0121 (5)
N10.0443 (6)0.0499 (7)0.0454 (6)0.0124 (5)0.0135 (5)0.0091 (5)
C10.0471 (7)0.0398 (6)0.0437 (7)0.0072 (5)0.0161 (6)0.0096 (5)
C20.0607 (9)0.0556 (9)0.0460 (8)0.0086 (7)0.0143 (7)0.0166 (6)
C30.0786 (12)0.0623 (10)0.0558 (9)0.0085 (8)0.0288 (9)0.0248 (8)
C40.0684 (11)0.0631 (10)0.0709 (11)0.0092 (8)0.0375 (9)0.0251 (8)
C50.0494 (8)0.0540 (8)0.0629 (9)0.0071 (6)0.0261 (7)0.0203 (7)
C60.0437 (7)0.0376 (6)0.0472 (7)0.0052 (5)0.0191 (6)0.0117 (5)
C70.0408 (6)0.0364 (6)0.0433 (7)0.0082 (5)0.0146 (5)0.0087 (5)
C80.0411 (6)0.0440 (7)0.0442 (7)0.0097 (5)0.0151 (5)0.0119 (5)
C90.0563 (9)0.0464 (8)0.0594 (9)0.0154 (6)0.0170 (7)0.0090 (6)
C100.0627 (10)0.0744 (11)0.0509 (9)0.0347 (9)0.0119 (7)0.0071 (8)
C110.0454 (8)0.0894 (13)0.0472 (8)0.0166 (8)0.0103 (6)0.0190 (8)
C120.0497 (9)0.0676 (10)0.0589 (9)0.0023 (7)0.0163 (7)0.0192 (8)
C130.0499 (8)0.0455 (7)0.0544 (8)0.0070 (6)0.0147 (6)0.0086 (6)
C140.0442 (7)0.0394 (6)0.0405 (6)0.0110 (5)0.0151 (5)0.0075 (5)
C150.0476 (7)0.0471 (7)0.0435 (7)0.0142 (6)0.0163 (6)0.0089 (5)
C160.0854 (13)0.0621 (10)0.0558 (9)0.0166 (9)0.0259 (9)0.0238 (8)
C170.0650 (11)0.0801 (13)0.0642 (11)0.0162 (9)0.0143 (9)0.0266 (9)
C180.0433 (7)0.0452 (7)0.0439 (7)0.0124 (5)0.0162 (5)0.0060 (5)
C190.0497 (8)0.0728 (11)0.0576 (9)0.0221 (8)0.0213 (7)0.0115 (8)
Geometric parameters (Å, º) top
C1—N11.3708 (19)C11—H110.93
C1—C61.415 (2)C12—C131.388 (2)
C1—C21.415 (2)C12—H120.93
C2—C31.365 (3)C13—H130.93
C2—H20.93C14—C181.433 (2)
C3—C41.403 (3)C14—C151.5031 (19)
C3—H30.93C15—O11.1841 (19)
C4—C51.371 (2)C15—O21.3132 (19)
C4—H40.93C16—O21.457 (2)
C5—C61.417 (2)C16—C171.485 (3)
C5—H50.93C16—H16A0.97
C6—C71.4268 (19)C16—H16B0.97
C7—C141.3775 (19)C17—H17A0.96
C7—C81.4939 (19)C17—H17B0.96
C8—C131.387 (2)C17—H17C0.96
C8—C91.391 (2)C18—N11.311 (2)
C9—C101.390 (2)C18—C191.503 (2)
C9—H90.93C19—H19A0.96
C10—C111.373 (3)C19—H19B0.96
C10—H100.93C19—H19C0.96
C11—C121.378 (3)
N1—C1—C6123.08 (13)C11—C12—H12120
N1—C1—C2117.62 (14)C13—C12—H12120
C6—C1—C2119.30 (14)C8—C13—C12120.70 (15)
C3—C2—C1120.59 (16)C8—C13—H13119.7
C3—C2—H2119.7C12—C13—H13119.7
C1—C2—H2119.7C7—C14—C18120.33 (13)
C2—C3—C4120.20 (16)C7—C14—C15120.08 (12)
C2—C3—H3119.9C18—C14—C15119.58 (12)
C4—C3—H3119.9O1—C15—O2124.63 (15)
C5—C4—C3120.81 (15)O1—C15—C14124.46 (14)
C5—C4—H4119.6O2—C15—C14110.91 (12)
C3—C4—H4119.6O2—C16—C17107.69 (15)
C4—C5—C6120.21 (16)O2—C16—H16A110.2
C4—C5—H5119.9C17—C16—H16A110.2
C6—C5—H5119.9O2—C16—H16B110.2
C1—C6—C5118.89 (13)C17—C16—H16B110.2
C1—C6—C7117.77 (12)H16A—C16—H16B108.5
C5—C6—C7123.35 (13)C16—C17—H17A109.5
C14—C7—C6117.96 (12)C16—C17—H17B109.5
C14—C7—C8122.12 (12)H17A—C17—H17B109.5
C6—C7—C8119.89 (12)C16—C17—H17C109.5
C13—C8—C9118.59 (14)H17A—C17—H17C109.5
C13—C8—C7120.19 (13)H17B—C17—H17C109.5
C9—C8—C7121.21 (13)N1—C18—C14122.27 (13)
C10—C9—C8120.56 (16)N1—C18—C19117.00 (14)
C10—C9—H9119.7C14—C18—C19120.73 (13)
C8—C9—H9119.7C18—C19—H19A109.5
C11—C10—C9120.00 (16)C18—C19—H19B109.5
C11—C10—H10120H19A—C19—H19B109.5
C9—C10—H10120C18—C19—H19C109.5
C10—C11—C12120.20 (16)H19A—C19—H19C109.5
C10—C11—H11119.9H19B—C19—H19C109.5
C12—C11—H11119.9C18—N1—C1118.58 (13)
C11—C12—C13119.94 (16)C15—O2—C16119.11 (13)
N1—C1—C2—C3178.06 (15)C10—C11—C12—C130.8 (3)
C6—C1—C2—C31.1 (2)C9—C8—C13—C121.3 (2)
C1—C2—C3—C40.8 (3)C7—C8—C13—C12177.08 (15)
C2—C3—C4—C50.1 (3)C11—C12—C13—C80.5 (3)
C3—C4—C5—C60.6 (3)C6—C7—C14—C180.5 (2)
N1—C1—C6—C5178.56 (13)C8—C7—C14—C18177.58 (12)
C2—C1—C6—C50.6 (2)C6—C7—C14—C15178.33 (11)
N1—C1—C6—C70.9 (2)C8—C7—C14—C153.6 (2)
C2—C1—C6—C7179.97 (12)C7—C14—C15—O176.8 (2)
C4—C5—C6—C10.3 (2)C18—C14—C15—O1102.0 (2)
C4—C5—C6—C7179.12 (14)C7—C14—C15—O2102.89 (16)
C1—C6—C7—C140.56 (19)C18—C14—C15—O278.24 (17)
C5—C6—C7—C14178.85 (13)C7—C14—C18—N11.5 (2)
C1—C6—C7—C8178.70 (12)C15—C14—C18—N1177.41 (13)
C5—C6—C7—C80.7 (2)C7—C14—C18—C19177.80 (14)
C14—C7—C8—C1379.78 (18)C15—C14—C18—C193.3 (2)
C6—C7—C8—C1398.29 (17)C14—C18—N1—C11.1 (2)
C14—C7—C8—C9101.92 (17)C19—C18—N1—C1178.13 (13)
C6—C7—C8—C980.01 (18)C6—C1—N1—C180.0 (2)
C13—C8—C9—C100.8 (2)C2—C1—N1—C18179.18 (13)
C7—C8—C9—C10177.53 (15)O1—C15—O2—C160.8 (3)
C8—C9—C10—C110.4 (3)C14—C15—O2—C16178.93 (15)
C9—C10—C11—C121.2 (3)C17—C16—O2—C15129.54 (19)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C16—H16A···O10.972.322.711 (3)103
C19—H19B···O2i0.962.523.374 (3)147
C19—H19C···O20.962.593.212 (3)122
C12—H12···Cg2ii0.932.953.750 (3)145
C17—H17C···Cg3iii0.962.973.883 (3)160
Symmetry codes: (i) x+1, y2, z+1; (ii) x+2, y, z+1; (iii) x+2, y, z.

Experimental details

Crystal data
Chemical formulaC19H17NO2
Mr291.34
Crystal system, space groupTriclinic, P1
Temperature (K)120
a, b, c (Å)9.0282 (10), 9.362 (1), 10.7258 (10)
α, β, γ (°)69.765 (8), 66.733 (8), 70.605 (8)
V3)761.08 (15)
Z2
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.35 × 0.32 × 0.25
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
8164, 3995, 3410
Rint0.044
(sin θ/λ)max1)0.687
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.065, 0.194, 1.09
No. of reflections3995
No. of parameters199
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.33, 0.35

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SHELXTL (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C16—H16A···O10.972.322.711 (3)103
C19—H19B···O2i0.962.523.374 (3)147
C19—H19C···O20.962.593.212 (3)122
C12—H12···Cg2ii0.932.953.750 (3)145
C17—H17C···Cg3iii0.962.973.883 (3)160
Symmetry codes: (i) x+1, y2, z+1; (ii) x+2, y, z+1; (iii) x+2, y, z.
 

Acknowledgements

The author is grateful to the Islamic Azad University, Dorood Branch, for financial support.

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