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ISSN: 2056-9890

Ethyl 2-(4-hydr­­oxy-1-methyl-2-oxo-1,2-di­hydro­quinolin-3-yl)acetate

aNational University of Pharmacy, 4 Blyukhera ave., Kharkiv 61002, Ukraine, and bSTC "Institute for Single Crystals", National Academy of Sciences of Ukraine, 60 Lenina ave., Kharkiv 61001, Ukraine
*Correspondence e-mail: uiv@kharkov.ua

(Received 20 March 2009; accepted 31 March 2009; online 8 April 2009)

In the title compound, C14H15NO4, the bicyclic fragment and the ester group form a dihedral angle of 86.7 (2)°. Inter­molecular O—H⋯O and C—H⋯O hydrogen bonding connects mol­ecules into a helix along the crystallographic b axis.

Related literature

For esters of 4-hydr­oxy-2-oxo-1,2-dihydro­quinolin-3-acetic acids as non-steroidal anti-inflammatory drugs, see: Ukrainets et al. (2001[Ukrainets, I. V., Kamenetskaya, O. L., Taran, S. G., Petukhova, I. Yu. & Voronina, L. N. (2001). Khim. Geterotsikl. Soedin. pp. 104-107.]). For their use in the synthesis of natural alkaloids, see: Ramesh & Shanmugam (1985[Ramesh, M. & Shanmugam, P. (1985). Indian J. Chem. Sect. B, 24, 602-604.]); Geismann & Cho (1959[Geismann, T. A. & Cho, A. K. (1959). J. Org. Chem. 24, 41-43.]) and in highly active anti­thyroid substances, see: Ukrainets et al. (1997[Ukrainets, I. V., Taran, S. G., Kodolova, O. L., Gorokhova, O. V. & Kravchenko, V. N. (1997). Khim. Geterotsikl. Soedin. pp. 1100-1104.]). For van der Waals radii, see: Zefirov (1997[Zefirov, Yu. V. (1997). Kristallografiya, 42, 936-958.]). For related structures, see: Jurd et al. (1983[Jurd, L., Benson, M. & Wong, R. Y. (1983). Aust. J. Chem. 36, 759-764.]); Ukrainets et al. (2000[Ukrainets, I. V., Taran, S. G., Kamenetskaya, O. L., Gorokhova, O. V., Sidorenko, L. V. & Turov, A. V. (2000). Khim. Geterotsikl. Soedin. pp. 1532-1535.]). For bond-length data, see: Bürgi & Dunitz (1994[Bürgi, H.-B. & Dunitz, J. D. (1994). Structure Correlation, Vol. 2, pp. 767-784. Weinheim: VCH.]).

[Scheme 1]

Experimental

Crystal data
  • C14H15NO4

  • Mr = 261.27

  • Monoclinic, C 2/c

  • a = 21.608 (2) Å

  • b = 9.2155 (9) Å

  • c = 14.6795 (12) Å

  • β = 119.632 (9)°

  • V = 2540.8 (4) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 293 K

  • 0.30 × 0.30 × 0.20 mm

Data collection
  • Oxford Diffraction Xcalibur3 diffractometer

  • Absorption correction: none

  • 13114 measured reflections

  • 2862 independent reflections

  • 2376 reflections with I > 2σ(I)

  • Rint = 0.030

Refinement
  • R[F2 > 2σ(F2)] = 0.060

  • wR(F2) = 0.171

  • S = 1.19

  • 2862 reflections

  • 232 parameters

  • All H-atom parameters refined

  • Δρmax = 0.28 e Å−3

  • Δρmin = −0.19 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2O⋯O1i 0.95 (3) 1.71 (3) 2.649 (2) 169 (2)
C10—H10a⋯O1i 0.94 (2) 2.34 (3) 3.235 (2) 159 (2)
Symmetry code: (i) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: CrysAlis CCD (Oxford Diffraction, 2005[Oxford Diffraction (2005). CrysAlis CCD and CrysAlis RED. Oxford Diffraction, Abingdon, England.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2005[Oxford Diffraction (2005). CrysAlis CCD and CrysAlis RED. Oxford Diffraction, Abingdon, England.]); data reduction: CrysAlis RED; 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: XP (Siemens, 1998[Siemens (1998). XP. Siemens Analytical X-ray Division, Inc., Karlsruhe, Germany.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Esters of 4-hydroxy-2-oxo-1,2-dihydroquinolin-3-acetic acids can be considered as non-steroid anti-inflammatory drugs (Ukrainets et al., 2001). However they are of great interest for synthesis of natural alkaloids (Ramesh & Shanmugam, 1985; Geismann & Cho, 1959) and highly active antithyroid substances (Ukrainets et al., 1997). In the present paper, we report the crystal structure of the (4-hydroxy-1-methyl-2-oxo-1,2-dihydro- quinolin-3-yl)-acetic acid ethyl ester (I) (Fig. 1). The bicyclic fragment and the C14, O1, C10 and O2 atoms are coplanar within 0.02 Å. The planar ester group at the C10 atom has orthogonal orientation with respect to the plane of quinolone bicycle (the C7—C8—C10—C11 torsion angle is 90.8 (2) %A) whereas the C8—C10—C11—O3 torsion angle is 7.3 (3) %A). The C9—O1 bond (1.250 (2) Å) is elongated as compared with its mean value (1.210 Å; Bürgi & Dunitz, 1994) owing to the formation of the intermolecular hydrogen bond O2—H2O···O1' (Table 1). The presence of hydrogen bond affects the orientation of the hydrogen atom of hydroxy group despite of strong repulsion with hydrogen atom of neighbouring methylene group: distance H10a···H2O is 2.09 Å [the van der Waals radii sum is 2.34 Å (Zefirov, 1997)]. It should be noted that the C7—O2 bond length (1.341 (2) Å) is close to its mean value 1.333 Å observed in earlier investigated compounds (Jurd et al., 1983; Ukrainets et al., 2000). In the crystal the molecules form the infinite helix along the [0 1 0] direction (Fig. 2) via the O2—H2O···O1 intermolecular hydrogen bond between hydroxyl group of one molecule and carbonyl group of quinolone fragment of neighbouring molecule. The C10—H10a···O1' intermolecular hydrogen bond (Table 1) occurs as well.

Related literature top

For ssters of 4-hydroxy-2-oxo-1,2-dihydroquinolin-3-acetic acids as non-steroidal anti-inflammatory drugs, see: Ukrainets et al. (2001). For their use in the synthesis of natural alkaloids, see: Ramesh & Shanmugam (1985); Geismann & Cho (1959) and in highly active antithyroid substances, see: Ukrainets et al. (1997). For van der Waals radii, see: Zefirov (1997). For related structures, see: Jurd et al. (1983); Ukrainets et al. (2000). For bond-length data, see: Bürgi & Dunitz (1994).

Experimental top

(4-Hydroxy-1-methyl-2-oxo-1,2-dihydroquinolin-3-yl)-acetic acid is synthesized from the methyl N-methyl anthranilate using the known method (Geismann & Cho, 1959) and then is esterified by ethanol (Ukrainets et al., 2001). Yield 96%. M.p. 454–457 K.

Refinement top

All hydrogen atoms were located from electron density difference maps and were refined isotropically.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2005); cell refinement: CrysAlis RED (Oxford Diffraction, 2005); data reduction: CrysAlis RED (Oxford Diffraction, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: XP (Siemens, 1998); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. View of the title compound with atomic numbering. All atoms are shown with displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. The packing of the molecules in a crystal. The hydrogen bonds are shown by dashed lines.
Ethyl 2-(4-hydroxy-1-methyl-2-oxo-1,2-dihydroquinolin-3-yl)acetate top
Crystal data top
C14H15NO4Dx = 1.366 Mg m3
Mr = 261.27Melting point: 455 K
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
a = 21.608 (2) ÅCell parameters from 8736 reflections
b = 9.2155 (9) Åθ = 4–32°
c = 14.6795 (12) ŵ = 0.10 mm1
β = 119.632 (9)°T = 293 K
V = 2540.8 (4) Å3Block, colourless
Z = 80.30 × 0.30 × 0.20 mm
F(000) = 1104
Data collection top
Oxford Diffraction Xcalibur3
diffractometer
2376 reflections with I > 2σ(I)
Radiation source: Enhance (Mo) X-ray SourceRint = 0.030
Graphite monochromatorθmax = 27.5°, θmin = 3.2°
Detector resolution: 16.1827 pixels mm-1h = 2828
ω scansk = 1111
13114 measured reflectionsl = 1919
2862 independent reflections
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)] = 0.060Hydrogen site location: difference Fourier map
wR(F2) = 0.171All H-atom parameters refined
S = 1.19 w = 1/[σ2(Fo2) + (0.0943P)2]
where P = (Fo2 + 2Fc2)/3
2862 reflections(Δ/σ)max < 0.001
232 parametersΔρmax = 0.28 e Å3
0 restraintsΔρmin = 0.19 e Å3
Crystal data top
C14H15NO4V = 2540.8 (4) Å3
Mr = 261.27Z = 8
Monoclinic, C2/cMo Kα radiation
a = 21.608 (2) ŵ = 0.10 mm1
b = 9.2155 (9) ÅT = 293 K
c = 14.6795 (12) Å0.30 × 0.30 × 0.20 mm
β = 119.632 (9)°
Data collection top
Oxford Diffraction Xcalibur3
diffractometer
2376 reflections with I > 2σ(I)
13114 measured reflectionsRint = 0.030
2862 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0600 restraints
wR(F2) = 0.171All H-atom parameters refined
S = 1.19Δρmax = 0.28 e Å3
2862 reflectionsΔρmin = 0.19 e Å3
232 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.

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
N10.12615 (8)0.48562 (16)0.00279 (10)0.0447 (4)
O10.23317 (6)0.38519 (13)0.11389 (9)0.0511 (4)
O20.14804 (7)0.78108 (14)0.22763 (10)0.0528 (4)
H2O0.1932 (14)0.807 (3)0.284 (2)0.086 (8)*
O30.21567 (7)0.39416 (16)0.34316 (11)0.0651 (4)
O40.32312 (6)0.48690 (14)0.45168 (9)0.0525 (4)
C10.07158 (8)0.58298 (18)0.01697 (12)0.0434 (4)
C20.00694 (10)0.5816 (2)0.11336 (15)0.0566 (5)
H20.0020 (13)0.511 (3)0.161 (2)0.077 (7)*
C30.04624 (10)0.6786 (3)0.13061 (17)0.0652 (6)
H30.0931 (15)0.677 (3)0.195 (2)0.102 (9)*
C40.03752 (10)0.7799 (3)0.05606 (18)0.0638 (6)
H40.0737 (14)0.850 (3)0.064 (2)0.087 (7)*
C50.02492 (9)0.7826 (2)0.03876 (16)0.0541 (5)
H50.0334 (10)0.852 (2)0.0948 (15)0.054 (5)*
C60.07974 (8)0.68292 (17)0.05940 (13)0.0419 (4)
C70.14509 (8)0.68166 (17)0.15888 (12)0.0393 (4)
C80.19716 (8)0.58370 (17)0.17776 (12)0.0390 (4)
C90.18749 (9)0.47940 (18)0.09900 (12)0.0407 (4)
C100.26583 (8)0.57643 (19)0.28059 (12)0.0413 (4)
H10B0.3055 (9)0.5445 (19)0.2663 (13)0.042 (4)*
H10A0.2774 (9)0.668 (2)0.3117 (14)0.044 (5)*
C110.26352 (8)0.47532 (18)0.35929 (13)0.0416 (4)
C120.32854 (11)0.3976 (2)0.53692 (15)0.0564 (5)
H12B0.2882 (13)0.416 (3)0.5450 (19)0.082 (7)*
H12A0.3291 (12)0.291 (3)0.5182 (18)0.084 (7)*
C130.39738 (15)0.4393 (3)0.63283 (17)0.0757 (7)
H13C0.3974 (17)0.546 (4)0.658 (2)0.132 (12)*
H13B0.4378 (17)0.416 (4)0.623 (3)0.119 (11)*
H13A0.4017 (15)0.380 (3)0.688 (2)0.105 (9)*
C140.11943 (14)0.3847 (3)0.07860 (17)0.0627 (5)
H14C0.1113 (13)0.444 (3)0.1404 (19)0.084 (7)*
H14B0.1627 (16)0.332 (3)0.050 (2)0.105 (10)*
H14A0.0770 (14)0.324 (3)0.0999 (19)0.080 (7)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0472 (8)0.0479 (8)0.0323 (7)0.0083 (6)0.0145 (6)0.0011 (6)
O10.0542 (7)0.0477 (7)0.0450 (7)0.0045 (5)0.0196 (6)0.0028 (5)
O20.0436 (7)0.0519 (7)0.0528 (7)0.0003 (5)0.0160 (6)0.0072 (6)
O30.0505 (8)0.0751 (10)0.0550 (8)0.0127 (6)0.0149 (6)0.0126 (7)
O40.0458 (7)0.0627 (8)0.0352 (6)0.0027 (5)0.0095 (5)0.0072 (5)
C10.0368 (8)0.0472 (9)0.0359 (8)0.0093 (7)0.0101 (7)0.0112 (7)
C20.0476 (10)0.0667 (13)0.0378 (9)0.0157 (9)0.0075 (8)0.0124 (9)
C30.0387 (10)0.0794 (15)0.0531 (11)0.0089 (9)0.0040 (8)0.0275 (11)
C40.0373 (10)0.0654 (13)0.0707 (13)0.0015 (9)0.0129 (9)0.0215 (11)
C50.0400 (9)0.0511 (11)0.0597 (11)0.0004 (8)0.0159 (8)0.0127 (9)
C60.0345 (8)0.0410 (9)0.0417 (8)0.0051 (6)0.0123 (7)0.0121 (7)
C70.0356 (8)0.0383 (8)0.0380 (8)0.0068 (6)0.0137 (6)0.0032 (6)
C80.0356 (8)0.0384 (8)0.0337 (8)0.0037 (6)0.0100 (6)0.0046 (6)
C90.0420 (9)0.0398 (8)0.0356 (8)0.0045 (6)0.0156 (7)0.0050 (6)
C100.0340 (8)0.0394 (9)0.0380 (9)0.0014 (6)0.0084 (7)0.0008 (6)
C110.0365 (8)0.0442 (9)0.0372 (8)0.0059 (6)0.0128 (7)0.0017 (6)
C120.0600 (12)0.0693 (14)0.0412 (10)0.0198 (9)0.0259 (9)0.0129 (9)
C130.0800 (17)0.0909 (19)0.0360 (10)0.0189 (14)0.0134 (10)0.0088 (11)
C140.0691 (14)0.0706 (14)0.0398 (10)0.0091 (11)0.0204 (10)0.0092 (10)
Geometric parameters (Å, º) top
N1—C91.380 (2)C5—H50.98 (2)
N1—C11.393 (2)C6—C71.445 (2)
N1—C141.463 (3)C7—C81.360 (2)
O1—C91.250 (2)C8—C91.437 (2)
O2—C71.341 (2)C8—C101.507 (2)
O2—H2O0.95 (3)C10—C111.504 (2)
O3—C111.201 (2)C10—H10B1.021 (18)
O4—C111.335 (2)C10—H10A0.935 (19)
O4—C121.453 (2)C12—C131.507 (3)
C1—C61.393 (2)C12—H12B0.95 (2)
C1—C21.414 (2)C12—H12A1.02 (3)
C2—C31.377 (3)C13—H13C1.05 (4)
C2—H20.92 (3)C13—H13B0.98 (3)
C3—C41.378 (3)C13—H13A0.94 (3)
C3—H30.99 (3)C14—H14C1.00 (3)
C4—C51.379 (3)C14—H14B0.95 (3)
C4—H40.97 (3)C14—H14A0.98 (3)
C5—C61.409 (2)
C9—N1—C1121.71 (14)O1—C9—C8122.39 (14)
C9—N1—C14117.82 (16)N1—C9—C8118.67 (14)
C1—N1—C14120.46 (16)C11—C10—C8114.00 (13)
C7—O2—H2O118.5 (15)C11—C10—H10B109.2 (10)
C11—O4—C12117.13 (15)C8—C10—H10B108.6 (10)
C6—C1—N1120.06 (14)C11—C10—H10A106.7 (11)
C6—C1—C2118.72 (17)C8—C10—H10A110.0 (10)
N1—C1—C2121.21 (17)H10B—C10—H10A108.2 (14)
C3—C2—C1120.0 (2)O3—C11—O4123.65 (16)
C3—C2—H2123.1 (16)O3—C11—C10125.92 (15)
C1—C2—H2116.8 (16)O4—C11—C10110.43 (14)
C2—C3—C4121.30 (18)O4—C12—C13106.40 (19)
C2—C3—H3122.3 (17)O4—C12—H12B108.5 (15)
C4—C3—H3116.4 (16)C13—C12—H12B112.4 (14)
C3—C4—C5119.7 (2)O4—C12—H12A108.7 (14)
C3—C4—H4124.4 (15)C13—C12—H12A111.0 (13)
C5—C4—H4115.9 (16)H12B—C12—H12A110 (2)
C4—C5—C6120.3 (2)C12—C13—H13C113.3 (18)
C4—C5—H5122.7 (11)C12—C13—H13B110 (2)
C6—C5—H5117.1 (11)H13C—C13—H13B114 (3)
C1—C6—C5119.99 (15)C12—C13—H13A106.8 (18)
C1—C6—C7118.66 (14)H13C—C13—H13A105 (3)
C5—C6—C7121.36 (17)H13B—C13—H13A107 (3)
O2—C7—C8124.99 (14)N1—C14—H14C107.4 (15)
O2—C7—C6114.46 (14)N1—C14—H14B106.9 (18)
C8—C7—C6120.53 (15)H14C—C14—H14B112 (2)
C7—C8—C9120.23 (14)N1—C14—H14A108.7 (15)
C7—C8—C10122.64 (15)H14C—C14—H14A107.6 (19)
C9—C8—C10117.11 (14)H14B—C14—H14A114 (2)
O1—C9—N1118.92 (15)
C9—N1—C1—C63.6 (2)O2—C7—C8—C9178.40 (14)
C14—N1—C1—C6177.17 (16)C6—C7—C8—C90.4 (2)
C9—N1—C1—C2175.56 (14)O2—C7—C8—C100.3 (2)
C14—N1—C1—C23.7 (2)C6—C7—C8—C10179.14 (14)
C6—C1—C2—C30.5 (2)C1—N1—C9—O1176.58 (14)
N1—C1—C2—C3179.68 (15)C14—N1—C9—O12.7 (2)
C1—C2—C3—C41.1 (3)C1—N1—C9—C84.7 (2)
C2—C3—C4—C51.5 (3)C14—N1—C9—C8176.02 (16)
C3—C4—C5—C60.2 (3)C7—C8—C9—O1178.23 (15)
N1—C1—C6—C5179.10 (14)C10—C8—C9—O10.5 (2)
C2—C1—C6—C51.7 (2)C7—C8—C9—N13.1 (2)
N1—C1—C6—C70.8 (2)C10—C8—C9—N1178.10 (13)
C2—C1—C6—C7178.41 (14)C7—C8—C10—C1190.75 (19)
C4—C5—C6—C11.4 (3)C9—C8—C10—C1187.98 (19)
C4—C5—C6—C7178.75 (16)C12—O4—C11—O31.4 (2)
C1—C6—C7—O2179.69 (13)C12—O4—C11—C10178.93 (15)
C5—C6—C7—O20.4 (2)C8—C10—C11—O37.3 (3)
C1—C6—C7—C80.7 (2)C8—C10—C11—O4173.09 (13)
C5—C6—C7—C8179.38 (15)C11—O4—C12—C13175.83 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2O···O1i0.95 (3)1.71 (3)2.649 (2)169 (2)
C10—H10a···O1i0.94 (2)2.34 (3)3.235 (2)159 (2)
Symmetry code: (i) x+1/2, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC14H15NO4
Mr261.27
Crystal system, space groupMonoclinic, C2/c
Temperature (K)293
a, b, c (Å)21.608 (2), 9.2155 (9), 14.6795 (12)
β (°) 119.632 (9)
V3)2540.8 (4)
Z8
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.30 × 0.30 × 0.20
Data collection
DiffractometerOxford Diffraction Xcalibur3
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
13114, 2862, 2376
Rint0.030
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.060, 0.171, 1.19
No. of reflections2862
No. of parameters232
H-atom treatmentAll H-atom parameters refined
Δρmax, Δρmin (e Å3)0.28, 0.19

Computer programs: CrysAlis CCD (Oxford Diffraction, 2005), CrysAlis RED (Oxford Diffraction, 2005), SHELXTL (Sheldrick, 2008), XP (Siemens, 1998).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2O···O1i0.95 (3)1.71 (3)2.649 (2)169 (2)
C10—H10a···O1i0.94 (2)2.34 (3)3.235 (2)159 (2)
Symmetry code: (i) x+1/2, y+1/2, z+1/2.
 

References

First citationBürgi, H.-B. & Dunitz, J. D. (1994). Structure Correlation, Vol. 2, pp. 767-784. Weinheim: VCH.  Google Scholar
First citationGeismann, T. A. & Cho, A. K. (1959). J. Org. Chem. 24, 41–43.  Google Scholar
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