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3-Ethyl-4-hy­dr­oxy-8-meth­­oxy­quinolin-2(1H)-one

aDepartment of Chemistry, Faculty of Technology, Tomas Bata University in Zlin, Zlin 76272, Czech Republic, and bFaculty of Chemistry and Chemical Technology, University of Ljubljana, SI-1000 Ljubljana, Slovenia
*Correspondence e-mail: andrej.pevec@fkkt.uni-lj.si

(Received 15 October 2012; accepted 17 October 2012; online 24 October 2012)

In the title compound, C12H13NO3, the quinoline ring system is approximately planar with a maximum deviation from the least-squares plane of 0.058 (2) Å. In the crystal, N—H⋯O and O—H⋯O hydrogen bonds link the mol­ecules into chains running along the b-axis direction. The chains also feature ππ inter­actions between pyridine and benzene rings of inversion-related mol­ecules [centroid–centroid distance = 3.609 (2) Å].

Related literature

For naturally occurring 3-alkyl-4-hy­droxy­quinolin-2-ones, see: Paul & Bose (1968[Paul, B. D. & Bose, P. K. (1968). J. Indian Chem. Soc. 45, 552-553.]); Faizutdinova et al. (1969[Faizutdinova, Z. Sh., Bessonova, I. A. & Yunusov, S. Yu. (1969). Khim. Prir. Soedin. 5, 455-456.]); Jurd et al. (1983[Jurd, L., Benson, M. & Wong, R. Y. (1983). Aust. J. Chem. 36, 759-768.]); Chen et al. (1994[Chen, I. S., Wu, S. J., Lin, Y. C., Tsai, I. L., Seki, H., Ko, F. N. & Teng, C. M. (1994). Phytochemistry, 36, 237-240.]); Yamamoto & Harimaya (2004[Yamamoto, Y. & Harimaya, K. (2004). Chem. Lett. 33, 238-239.]); Jain et al. (2006[Jain, S. C., Pandey, M. K., Upadhyay, R. K., Kumar, R., Hundal, G. & Hundal, M. S. (2006). Phytochemistry, 67, 1005-1010.]). For the first published synthesis of the title compound, see: Rapoport & Holden (1959[Rapoport, H. & Holden, K. G. (1959). J. Am. Chem. Soc. 81, 3738-3743.]). For recent synthetic utilization of 3-alkyl-4-hy­droxy­quinolin-2-ones, see, for example: Kimmel et al. (2010[Kimmel, R., Kafka, S. & Košmrlj, J. (2010). Carbohydr. Res. 345, 768-779.]).

[Scheme 1]

Experimental

Crystal data
  • C12H13NO3

  • Mr = 219.23

  • Monoclinic, P 21 /c

  • a = 11.4824 (4) Å

  • b = 6.9072 (2) Å

  • c = 14.4978 (5) Å

  • β = 113.1283 (15)°

  • V = 1057.42 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 293 K

  • 0.35 × 0.25 × 0.08 mm

Data collection
  • Nonius KappaCCD area-detector diffractometer

  • Absorption correction: multi-scan (SCALEPACK; Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]) Tmin = 0.966, Tmax = 0.992

  • 4558 measured reflections

  • 2403 independent reflections

  • 1734 reflections with I > 2σ(I)

  • Rint = 0.025

Refinement
  • R[F2 > 2σ(F2)] = 0.077

  • wR(F2) = 0.272

  • S = 1.14

  • 2403 reflections

  • 151 parameters

  • 1 restraint

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.37 e Å−3

  • Δρmin = −0.29 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N⋯O1i 0.85 (2) 2.27 (3) 2.976 (4) 140 (3)
O2—H2⋯O1ii 0.82 1.94 2.665 (4) 147
Symmetry codes: (i) -x, -y+2, -z; (ii) x, y-1, z.

Data collection: COLLECT (Nonius, 1998[Nonius (1998). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO and SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO and SCALEPACK; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) and DIAMOND (Brandenburg, 1999[Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

The title compound, (I) (Fig. 1), was recently prepared as an intermediate within the framework of a study focusing on glucosylation of N-unsubstituted 4-hydroxyquinolin-2(1H)-ones by thermal condensation of diethyl ethylmalonate with o-anisidine (Kimmel et al., 2010). Some 3-alkyl-4-hydroxyquinolin-2-ones were isolated from plants Ravenia spectabilis (Paul & Bose, 1968), Haplophylum bucharicum (Faizutdinova et al., 1969), Euxylophora pareansis (Jurd et al., 1983), Zanthoxylum simulans (Chen et al., 1994), Toddalia aculeata (Jain et al., 2006) as well as from the fermentation broth of Dactylosporangium sp. (Yamamoto & Harimaya, 2004).

In the crystal structure of the title compound (I) (Fig. 2) two 3-ethyl-4-hydroxy-8-methoxyquinolin-2(1H)-one molecules are connected by two intermolecular N—H···O hydrogen bonds between protonated nitrogen atom and carbonyl group. These connections altogether with additional O—H···O hydrogen bonds between hydroxyl and carbonyl groups (Table 1) form linear chain along b axis. The chains are further stabilized by ππ interactions between pyridine and benzene rings of inversion-related pairs of quinoline molecules [centroid–centroid distance = 3.609 (2) Å].

Related literature top

For naturally occurring 3-alkyl-4-hydroxyquinolin-2-ones, see: Paul & Bose (1968); Faizutdinova et al. (1969); Jurd et al. (1983); Chen et al. (1994); Yamamoto & Harimaya (2004); Jain et al. (2006). For the first published synthesis of the title compound, see: Rapoport & Holden (1959). For recent synthetic utilization of 3-alkyl-4-hydroxyquinolin-2-ones, see, for example: Kimmel et al. (2010).

Experimental top

A mixture of o-anisidine (12.3 g, 100 mmol) and diethyl ethylmalonate (197.6 g, 105 mmol) was heated on a metal bath at 220–230 °C for 1 h and then at 260–270 °C for 6 h (until the distillation of ethanol stopped). The hot reaction mixture was cautiously poured into toluene (50 ml). After cooling, the precipitate was filtered. The residue was dissolved in aqueous sodium hydroxide solution (0.5 M, 300 ml) and the solution was filtered. The filtrate was washed with toluene (3 x 15 ml). The aqueous phase was filtered and acidified by addition of 10% hydrochloric acid to Congo red. The precipitated paste was triturated with a glass bar under an aqueous phase for several minutes and then the mixture was cooled in refrigerator for several hours, until the pasty substance hardened. The solid was filtered off, washed with water (100 ml), air dried and crystallized from ethanol affording 13.6 g (62% of theoretical yield) of the title compound (I), m. pt 496–498 K (benzene – ethanol). In the literature (Rapoport & Holden, 1959), a m. pt range of 498–499 K is reported.

Refinement top

The N–bonded hydrogen atom was located in a difference map and refined with the using a distance restraint, N—H = 0.86±0.02 Å, and with Uiso(H) = 1.2Ueq(N). All other H atoms were included in the model at geometrically calculated positions and refined using a riding model, with C—H bond lengths constrained to 0.93 Å (aromatic H), 0.96 Å (methyl H), 0.97 Å (methylene H) and O—H = 0.82 Å, and with Uiso(H) values of 1.2Ueq(C) [for aromatic and methylene H] or 1.5Ueq(C) [for oxygen and methyl H]. The exceptionally large value for the first parameter on the SHELXL weighting line altogether with large value for weighted R factor indicate possible twinning. The function TwinRotMat in PLATON (Spek, 2009) suggests that the structure could be twinned. However, applying the proposed twin law does not affect the refinement in the sense of better R values. Additionally, the BASF parameter has a value close to zero after refinement. Hence, a twin model was not employed.

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: DENZO and SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009) and DIAMOND (Brandenburg, 1999); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. A view of the title compound showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. The supramolecular chain in the crystal structure of (I), with the O—H···O and N—H···O hydrogen bonds, and ππ interactions denoted by dashed lines. Hydrogen atoms not involved in hydrogen bonding have been omitted for clarity. [Symmetry codes: (i) -x, -y + 2, -z; (ii) x, y - 1, z]
3-Ethyl-4-hydroxy-8-methoxyquinolin-2(1H)-one top
Crystal data top
C12H13NO3F(000) = 464
Mr = 219.23Dx = 1.377 Mg m3
Monoclinic, P21/cMelting point = 496–498 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 11.4824 (4) ÅCell parameters from 2554 reflections
b = 6.9072 (2) Åθ = 0.4–27.5°
c = 14.4978 (5) ŵ = 0.10 mm1
β = 113.1283 (15)°T = 293 K
V = 1057.42 (6) Å3Prism, colourless
Z = 40.35 × 0.25 × 0.08 mm
Data collection top
Nonius KappaCCD area-detector
diffractometer
2403 independent reflections
Radiation source: fine-focus sealed tube1734 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.025
ϕ scans + ω scansθmax = 27.5°, θmin = 3.1°
Absorption correction: multi-scan
(SCALEPACK; Otwinowski & Minor, 1997)
h = 1414
Tmin = 0.966, Tmax = 0.992k = 88
4558 measured reflectionsl = 1818
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)] = 0.077Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.272H atoms treated by a mixture of independent and constrained refinement
S = 1.14 w = 1/[σ2(Fo2) + (0.1076P)2 + 1.7454P]
where P = (Fo2 + 2Fc2)/3
2403 reflections(Δ/σ)max = 0.0001
151 parametersΔρmax = 0.37 e Å3
1 restraintΔρmin = 0.29 e Å3
Crystal data top
C12H13NO3V = 1057.42 (6) Å3
Mr = 219.23Z = 4
Monoclinic, P21/cMo Kα radiation
a = 11.4824 (4) ŵ = 0.10 mm1
b = 6.9072 (2) ÅT = 293 K
c = 14.4978 (5) Å0.35 × 0.25 × 0.08 mm
β = 113.1283 (15)°
Data collection top
Nonius KappaCCD area-detector
diffractometer
2403 independent reflections
Absorption correction: multi-scan
(SCALEPACK; Otwinowski & Minor, 1997)
1734 reflections with I > 2σ(I)
Tmin = 0.966, Tmax = 0.992Rint = 0.025
4558 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0771 restraint
wR(F2) = 0.272H atoms treated by a mixture of independent and constrained refinement
S = 1.14Δρmax = 0.37 e Å3
2403 reflectionsΔρmin = 0.29 e Å3
151 parameters
Special details top

Experimental. 279 frames in 4 sets of ϕ scans + ω scans. Rotation/frame = 1.6 °. Crystal-detector distance = 32 mm. Measuring time = 150 s/°.

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
N10.0025 (3)0.7822 (4)0.0870 (2)0.0373 (7)
H1N0.045 (3)0.880 (4)0.064 (3)0.045*
O10.1611 (2)0.9727 (3)0.0836 (2)0.0482 (7)
O20.2406 (2)0.3155 (4)0.1696 (2)0.0506 (7)
H20.19910.21510.15700.076*
O30.2344 (2)0.7758 (4)0.0700 (2)0.0584 (8)
C10.1260 (3)0.8088 (5)0.1009 (3)0.0362 (7)
C20.2089 (3)0.6432 (5)0.1318 (3)0.0370 (8)
C30.3448 (3)0.6709 (6)0.1462 (3)0.0437 (9)
H3A0.34970.77330.10200.052*
H3B0.37570.55280.12750.052*
C40.4286 (4)0.7222 (9)0.2532 (4)0.0740 (15)
H4A0.40280.84470.27020.111*
H4B0.51500.73030.25990.111*
H4C0.42120.62410.29750.111*
C50.1612 (3)0.4696 (5)0.1440 (2)0.0359 (7)
C60.0321 (3)0.4481 (5)0.1348 (2)0.0356 (7)
C70.0181 (3)0.2749 (5)0.1554 (3)0.0407 (8)
H70.03250.16510.17580.049*
C80.1418 (4)0.2694 (6)0.1450 (3)0.0473 (9)
H80.17490.15470.15800.057*
C90.2195 (3)0.4337 (6)0.1151 (3)0.0469 (9)
H90.30350.42690.10800.056*
C100.1721 (3)0.6033 (6)0.0964 (3)0.0412 (8)
C110.0451 (3)0.6117 (5)0.1052 (2)0.0353 (7)
C120.3645 (4)0.7815 (8)0.0518 (4)0.0780 (16)
H12A0.40910.68640.00220.117*
H12B0.39770.90780.02810.117*
H12C0.37530.75400.11290.117*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0334 (14)0.0319 (14)0.0455 (16)0.0049 (11)0.0145 (12)0.0054 (12)
O10.0463 (14)0.0305 (13)0.0695 (18)0.0029 (10)0.0246 (13)0.0036 (12)
O20.0354 (13)0.0334 (13)0.0717 (18)0.0040 (10)0.0091 (12)0.0001 (13)
O30.0389 (14)0.0581 (18)0.081 (2)0.0121 (12)0.0263 (14)0.0145 (15)
C10.0368 (16)0.0330 (17)0.0390 (17)0.0012 (13)0.0150 (14)0.0018 (13)
C20.0339 (16)0.0361 (17)0.0394 (17)0.0012 (13)0.0127 (13)0.0042 (14)
C30.0351 (17)0.0407 (19)0.055 (2)0.0013 (14)0.0170 (15)0.0026 (16)
C40.040 (2)0.103 (4)0.073 (3)0.020 (2)0.016 (2)0.031 (3)
C50.0339 (16)0.0325 (16)0.0357 (16)0.0027 (13)0.0078 (13)0.0011 (13)
C60.0377 (16)0.0358 (17)0.0291 (15)0.0024 (13)0.0084 (13)0.0026 (13)
C70.0445 (19)0.0371 (18)0.0388 (18)0.0023 (14)0.0144 (14)0.0037 (15)
C80.050 (2)0.046 (2)0.048 (2)0.0106 (17)0.0208 (17)0.0061 (17)
C90.0376 (18)0.059 (2)0.047 (2)0.0065 (16)0.0197 (15)0.0021 (18)
C100.0362 (17)0.048 (2)0.0388 (17)0.0028 (15)0.0143 (14)0.0013 (15)
C110.0349 (16)0.0359 (17)0.0330 (16)0.0012 (13)0.0110 (13)0.0006 (13)
C120.039 (2)0.083 (4)0.108 (4)0.017 (2)0.025 (2)0.000 (3)
Geometric parameters (Å, º) top
N1—C11.364 (4)C4—H4B0.9600
N1—C111.367 (4)C4—H4C0.9600
N1—H1N0.852 (19)C5—C61.443 (4)
O1—C11.260 (4)C6—C111.396 (5)
O2—C51.355 (4)C6—C71.409 (5)
O2—H20.8200C7—C81.369 (5)
O3—C101.365 (5)C7—H70.9300
O3—C121.412 (5)C8—C91.403 (6)
C1—C21.442 (5)C8—H80.9300
C2—C51.359 (5)C9—C101.363 (5)
C2—C31.503 (4)C9—H90.9300
C3—C41.512 (6)C10—C111.415 (5)
C3—H3A0.9700C12—H12A0.9600
C3—H3B0.9700C12—H12B0.9600
C4—H4A0.9600C12—H12C0.9600
C1—N1—C11123.9 (3)C2—C5—C6122.1 (3)
C1—N1—H1N115 (3)C11—C6—C7119.3 (3)
C11—N1—H1N121 (3)C11—C6—C5116.7 (3)
C5—O2—H2109.5C7—C6—C5123.9 (3)
C10—O3—C12118.4 (3)C8—C7—C6119.5 (3)
O1—C1—N1119.1 (3)C8—C7—H7120.2
O1—C1—C2123.4 (3)C6—C7—H7120.2
N1—C1—C2117.4 (3)C7—C8—C9121.2 (3)
C5—C2—C1119.3 (3)C7—C8—H8119.4
C5—C2—C3123.0 (3)C9—C8—H8119.4
C1—C2—C3117.7 (3)C10—C9—C8120.1 (3)
C2—C3—C4112.3 (3)C10—C9—H9120.0
C2—C3—H3A109.1C8—C9—H9120.0
C4—C3—H3A109.1C9—C10—O3126.9 (3)
C2—C3—H3B109.1C9—C10—C11119.7 (3)
C4—C3—H3B109.1O3—C10—C11113.4 (3)
H3A—C3—H3B107.9N1—C11—C6120.2 (3)
C3—C4—H4A109.5N1—C11—C10119.6 (3)
C3—C4—H4B109.5C6—C11—C10120.1 (3)
H4A—C4—H4B109.5O3—C12—H12A109.5
C3—C4—H4C109.5O3—C12—H12B109.5
H4A—C4—H4C109.5H12A—C12—H12B109.5
H4B—C4—H4C109.5O3—C12—H12C109.5
O2—C5—C2117.8 (3)H12A—C12—H12C109.5
O2—C5—C6120.0 (3)H12B—C12—H12C109.5
C11—N1—C1—O1178.8 (3)C5—C6—C7—C8179.6 (3)
C11—N1—C1—C23.3 (5)C6—C7—C8—C90.6 (5)
O1—C1—C2—C5176.7 (3)C7—C8—C9—C100.4 (6)
N1—C1—C2—C51.0 (5)C8—C9—C10—O3177.8 (4)
O1—C1—C2—C31.6 (5)C8—C9—C10—C111.4 (5)
N1—C1—C2—C3179.4 (3)C12—O3—C10—C95.3 (6)
C5—C2—C3—C489.5 (5)C12—O3—C10—C11175.5 (4)
C1—C2—C3—C492.3 (4)C1—N1—C11—C63.5 (5)
C1—C2—C5—O2177.8 (3)C1—N1—C11—C10174.7 (3)
C3—C2—C5—O20.5 (5)C7—C6—C11—N1178.6 (3)
C1—C2—C5—C65.1 (5)C5—C6—C11—N10.5 (5)
C3—C2—C5—C6176.7 (3)C7—C6—C11—C100.3 (5)
O2—C5—C6—C11178.1 (3)C5—C6—C11—C10178.8 (3)
C2—C5—C6—C114.8 (5)C9—C10—C11—N1179.6 (3)
O2—C5—C6—C72.8 (5)O3—C10—C11—N10.3 (5)
C2—C5—C6—C7174.3 (3)C9—C10—C11—C61.3 (5)
C11—C6—C7—C80.6 (5)O3—C10—C11—C6178.0 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O1i0.85 (2)2.27 (3)2.976 (4)140 (3)
O2—H2···O1ii0.821.942.665 (4)147
Symmetry codes: (i) x, y+2, z; (ii) x, y1, z.

Experimental details

Crystal data
Chemical formulaC12H13NO3
Mr219.23
Crystal system, space groupMonoclinic, P21/c
Temperature (K)293
a, b, c (Å)11.4824 (4), 6.9072 (2), 14.4978 (5)
β (°) 113.1283 (15)
V3)1057.42 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.35 × 0.25 × 0.08
Data collection
DiffractometerNonius KappaCCD area-detector
diffractometer
Absorption correctionMulti-scan
(SCALEPACK; Otwinowski & Minor, 1997)
Tmin, Tmax0.966, 0.992
No. of measured, independent and
observed [I > 2σ(I)] reflections
4558, 2403, 1734
Rint0.025
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.077, 0.272, 1.14
No. of reflections2403
No. of parameters151
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.37, 0.29

Computer programs: COLLECT (Nonius, 1998), DENZO and SCALEPACK (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and DIAMOND (Brandenburg, 1999), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O1i0.852 (19)2.27 (3)2.976 (4)140 (3)
O2—H2···O1ii0.821.942.665 (4)147
Symmetry codes: (i) x, y+2, z; (ii) x, y1, z.
 

Acknowledgements

This study was supported by the inter­nal grant of TBU in Zlin (No. IGA/FT/2012/043), funded from the resources of specific university research, and the Slovenian Research Agency (Project P1–0230–0103 and Joint Project BI—CZ/07–08–018). This work was also partly supported through the infrastructure of the EN–FIST Centre of Excellence, Ljubljana.

References

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