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ISSN: 2056-9890

8,8-Di­methyl-8,9-di­hydro-7H-chromeno[2,3-b]quinoline-10,12-dione

aCentre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India, and bIndustrial Chemistry Laboratory, Central Leather Research Institute, Adyar, Chennai 600 020, India
*Correspondence e-mail: shirai2011@gmail.com

(Received 4 January 2013; accepted 11 January 2013; online 19 January 2013)

In the title compound, C18H15NO3, the fused benzopyran and pyridine rings are essentially coplanar [r.m.s. deviation = 0.0533 Å with a maximum deviation of 0.080 (1) Å for a benzene C atom]. The cyclo­hexa­none ring adopts an envelope conformation with the dimethyl-substituted C atom 0.660 (2) Å out of the plane formed by the remaining ring atoms (r.m.s. deviation = 0.0305 Å). The dihedral angle between the mean planes of the pyran and cyclo­hexa­none rings is 12.95 (6)°. In the crystal, mol­ecules are linked via C—H⋯O hydrogen bonds, leading to chains running along [011].

Related literature

For the uses and biological importance of diketones, see: Bennett et al. (1999[Bennett, I., Broom, N. J. P., Cassels, R., Elder, J. S., Masson, N. D. & O'Hanlon, P. J. (1999). Bioorg. Med. Chem. Lett. 9, 1847-1852.]); Sato et al. (2008[Sato, K., Yamazoe, S., Yamamoto, R., Ohata, S., Tarui, A., Omote, M., Kumadaki, I. & Ando, A. (2008). Org. Lett. 10, 2405-2408.]). For a related structure, see: Öztürk Yildirim et al. (2012)[Öztürk Yildirim, S., Butcher, R. J., El-Khouly, A., Safak, C. & Şimsek, R. (2012). Acta Cryst. E68, o3365-o3366.].

[Scheme 1]

Experimental

Crystal data
  • C18H15NO3

  • Mr = 293.31

  • Triclinic, [P \overline 1]

  • a = 7.4426 (6) Å

  • b = 10.5117 (9) Å

  • c = 10.6887 (9) Å

  • α = 60.939 (4)°

  • β = 88.107 (5)°

  • γ = 77.546 (5)°

  • V = 711.22 (10) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 293 K

  • 0.30 × 0.25 × 0.20 mm

Data collection
  • Bruker SMART APEXII area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.972, Tmax = 0.982

  • 10655 measured reflections

  • 2949 independent reflections

  • 2427 reflections with I > 2σ(I)

  • Rint = 0.031

Refinement
  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.118

  • S = 1.05

  • 2949 reflections

  • 201 parameters

  • H-atom parameters constrained

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C15—H15⋯O2i 0.93 2.43 3.250 (2) 147
Symmetry code: (i) x-1, y+1, z-1.

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: ORTEP-3 (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Diketones are key intermediates in the preparation of various heterocyclic compounds (Sato et al., 2008) and are popular in organic synthesis for their applications in biology and medicine. They are known to exhibit antioxidant, antitumour and antibacterial activities (Bennett et al., 1999).

The bond distances and angles in the title compound (Fig. 1) agree very well with the corresponding bond distances and angles reported in a closely related compound (Öztürk Yildirim et al., 2012). The dihedral angle between the pyran ring (O3/C1/C2/C10/C11/C12) and the pyridine ring (N1/C2/C3/C4/C9/C10) is 3.08 (6)°. The dihedral angle between the pyran ring and the benzene ring (C11-C16) is 2.70 (6)°. Moreover, pyridine ring makes a diheral angle of 5.78 (6)° with the benzene ring (C11-C16). The dihedral angle between the pyran ring and the cyclohexanone ring is 12.95 (6)°. In the crystal, molecules are linked via C15–H15···O2 hydrogen bonding interactions leading to chains running along the b-axis (Table 1 & Fig. 2).

Related literature top

For the uses and biological importance of diketones, see: Bennett et al. (1999); Sato et al. (2008). For a related structure, see: Öztürk Yildirim et al. (2012).

Experimental top

2-Amino-4-oxo-4H-chromene-3-carbaldehyde (100 mg, 1.0 mmol) was reacted with 5,5-dimethylcyclohexane-1,3-dione (88 mg, 1.2 mmol) in the presence of yeterbium triflate (Yb(oft)3) (98 mg, 0.3 mmol) after stirring. All these reactants were dissolved in xylene (5 ml). The reaction mixture was refluxed at 398 K for 12 hours. The reaction mixture was extracted with ethyl acetate/hexane (40:60 v/v). The completion of the reaction was monitored by TLC. The end product was the title compound which was purified by column chromatography (ethyl acetate/hexane, 40:60), the yield being 80%. Single crystals suitable for X-ray diffraction were obtained by slow evaporation of a solution of the title compound in ethyl acetate at room temperature.

Refinement top

The hydrogen atoms were placed in calculated positions with C—H = 0.93 - 0.97 Å and refined in the riding model with fixed isotropic displacement parameters:Uiso(H) = 1.5Ueq(C) for methyl H-atoms and Uiso(H) = 1.2Ueq(C) for other H-atoms.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing displacement ellipsoids drawn at the 30% probability level. H atoms are presented as small spheres of arbitrary radius.
[Figure 2] Fig. 2. The crystal packing of the title compound viewed down a axis. H-atoms not involved in H-bonds have been excluded for clarity.
8,8-Dimethyl-8,9-dihydro-7H-chromeno[2,3-b]quinoline-10,12-dione top
Crystal data top
C18H15NO3Z = 2
Mr = 293.31F(000) = 308
Triclinic, P1Dx = 1.370 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.4426 (6) ÅCell parameters from 2949 reflections
b = 10.5117 (9) Åθ = 2.2–26.5°
c = 10.6887 (9) ŵ = 0.09 mm1
α = 60.939 (4)°T = 293 K
β = 88.107 (5)°Block, colourless
γ = 77.546 (5)°0.30 × 0.25 × 0.20 mm
V = 711.22 (10) Å3
Data collection top
Bruker SMART APEXII area-detector
diffractometer
2949 independent reflections
Radiation source: fine-focus sealed tube2427 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.031
ω and ϕ scansθmax = 26.5°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 99
Tmin = 0.972, Tmax = 0.982k = 1313
10655 measured reflectionsl = 1313
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)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.118H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0598P)2 + 0.1006P]
where P = (Fo2 + 2Fc2)/3
2949 reflections(Δ/σ)max < 0.001
201 parametersΔρmax = 0.17 e Å3
0 restraintsΔρmin = 0.22 e Å3
Crystal data top
C18H15NO3γ = 77.546 (5)°
Mr = 293.31V = 711.22 (10) Å3
Triclinic, P1Z = 2
a = 7.4426 (6) ÅMo Kα radiation
b = 10.5117 (9) ŵ = 0.09 mm1
c = 10.6887 (9) ÅT = 293 K
α = 60.939 (4)°0.30 × 0.25 × 0.20 mm
β = 88.107 (5)°
Data collection top
Bruker SMART APEXII area-detector
diffractometer
2949 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
2427 reflections with I > 2σ(I)
Tmin = 0.972, Tmax = 0.982Rint = 0.031
10655 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.118H-atom parameters constrained
S = 1.05Δρmax = 0.17 e Å3
2949 reflectionsΔρmin = 0.22 e Å3
201 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
C10.01482 (17)0.15363 (14)0.17863 (13)0.0415 (3)
C20.05259 (16)0.17700 (13)0.29891 (12)0.0375 (3)
C30.17358 (16)0.07117 (13)0.41692 (12)0.0388 (3)
H30.23320.01900.42240.047*
C40.20560 (16)0.09954 (13)0.52620 (12)0.0382 (3)
C50.33905 (17)0.01133 (14)0.65130 (13)0.0431 (3)
C60.37866 (19)0.03085 (15)0.76134 (13)0.0485 (3)
H6A0.50820.01060.79580.058*
H6B0.30720.01540.84230.058*
C70.33647 (18)0.19874 (14)0.70916 (13)0.0469 (3)
C80.13932 (19)0.26760 (16)0.63542 (14)0.0518 (3)
H8A0.05250.22900.70660.062*
H8B0.11360.37500.59660.062*
C90.10985 (16)0.23518 (13)0.51692 (12)0.0406 (3)
C100.03248 (16)0.30872 (13)0.29978 (13)0.0387 (3)
C110.18038 (16)0.41066 (14)0.06841 (12)0.0405 (3)
C120.10695 (16)0.28199 (14)0.05958 (13)0.0410 (3)
C130.15013 (18)0.28050 (16)0.06622 (13)0.0488 (3)
H130.10450.19510.07380.059*
C140.2593 (2)0.40430 (17)0.17835 (14)0.0542 (4)
H140.28650.40280.26180.065*
C150.32914 (18)0.53168 (16)0.16751 (14)0.0523 (3)
H150.40270.61520.24410.063*
C160.29078 (18)0.53585 (15)0.04437 (14)0.0481 (3)
H160.33820.62130.03720.058*
C170.3488 (2)0.22292 (19)0.83847 (16)0.0643 (4)
H17A0.47260.18180.88320.096*
H17B0.26530.17410.90630.096*
H17C0.31610.32800.80700.096*
C180.4756 (2)0.27038 (17)0.60480 (16)0.0608 (4)
H18A0.59750.22760.65320.091*
H18B0.44580.37610.57040.091*
H18C0.47110.25250.52510.091*
N10.00885 (14)0.33841 (12)0.40449 (11)0.0440 (3)
O10.08122 (15)0.03625 (11)0.17871 (10)0.0603 (3)
O20.40972 (15)0.13281 (11)0.66438 (11)0.0630 (3)
O30.14882 (12)0.42254 (9)0.18821 (9)0.0467 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0459 (7)0.0410 (7)0.0389 (6)0.0114 (5)0.0027 (5)0.0201 (5)
C20.0396 (6)0.0378 (6)0.0357 (6)0.0107 (5)0.0034 (5)0.0178 (5)
C30.0403 (6)0.0353 (6)0.0399 (6)0.0082 (5)0.0029 (5)0.0180 (5)
C40.0397 (6)0.0375 (6)0.0357 (6)0.0092 (5)0.0016 (5)0.0164 (5)
C50.0449 (7)0.0393 (7)0.0391 (6)0.0088 (5)0.0003 (5)0.0149 (5)
C60.0535 (7)0.0471 (7)0.0373 (6)0.0078 (6)0.0067 (5)0.0157 (6)
C70.0558 (8)0.0474 (7)0.0386 (6)0.0082 (6)0.0045 (5)0.0229 (6)
C80.0595 (8)0.0523 (8)0.0439 (7)0.0013 (6)0.0055 (6)0.0288 (6)
C90.0423 (6)0.0415 (6)0.0364 (6)0.0067 (5)0.0011 (5)0.0190 (5)
C100.0378 (6)0.0391 (6)0.0365 (6)0.0066 (5)0.0005 (5)0.0173 (5)
C110.0392 (6)0.0464 (7)0.0349 (6)0.0116 (5)0.0018 (5)0.0186 (5)
C120.0429 (6)0.0448 (7)0.0359 (6)0.0150 (5)0.0038 (5)0.0182 (5)
C130.0546 (8)0.0542 (8)0.0405 (7)0.0157 (6)0.0023 (6)0.0239 (6)
C140.0587 (8)0.0662 (9)0.0370 (7)0.0182 (7)0.0020 (6)0.0227 (6)
C150.0487 (7)0.0557 (8)0.0383 (7)0.0090 (6)0.0044 (5)0.0130 (6)
C160.0462 (7)0.0462 (7)0.0431 (7)0.0060 (6)0.0022 (5)0.0167 (6)
C170.0774 (10)0.0703 (10)0.0496 (8)0.0050 (8)0.0112 (7)0.0366 (8)
C180.0758 (10)0.0598 (9)0.0538 (8)0.0271 (8)0.0013 (7)0.0283 (7)
N10.0480 (6)0.0430 (6)0.0397 (5)0.0025 (5)0.0026 (4)0.0221 (5)
O10.0808 (7)0.0487 (6)0.0534 (6)0.0004 (5)0.0115 (5)0.0312 (5)
O20.0751 (7)0.0440 (6)0.0594 (6)0.0067 (5)0.0183 (5)0.0241 (5)
O30.0520 (5)0.0431 (5)0.0398 (5)0.0021 (4)0.0087 (4)0.0208 (4)
Geometric parameters (Å, º) top
C1—O11.2259 (15)C9—N11.3386 (15)
C1—C121.4635 (17)C10—N11.3256 (15)
C1—C21.4672 (16)C10—O31.3559 (14)
C2—C31.3854 (16)C11—O31.3778 (14)
C2—C101.3971 (17)C11—C161.3849 (17)
C3—C41.3775 (16)C11—C121.3924 (18)
C3—H30.9300C12—C131.4010 (17)
C4—C91.4070 (17)C13—C141.3723 (19)
C4—C51.4857 (16)C13—H130.9300
C5—O21.2118 (15)C14—C151.387 (2)
C5—C61.5009 (17)C14—H140.9300
C6—C71.5299 (19)C15—C161.3792 (18)
C6—H6A0.9700C15—H150.9300
C6—H6B0.9700C16—H160.9300
C7—C181.526 (2)C17—H17A0.9600
C7—C171.5308 (17)C17—H17B0.9600
C7—C81.5369 (18)C17—H17C0.9600
C8—C91.4963 (17)C18—H18A0.9600
C8—H8A0.9700C18—H18B0.9600
C8—H8B0.9700C18—H18C0.9600
O1—C1—C12123.35 (11)N1—C10—O3112.77 (10)
O1—C1—C2122.30 (11)N1—C10—C2125.36 (11)
C12—C1—C2114.34 (10)O3—C10—C2121.86 (10)
C3—C2—C10116.41 (11)O3—C11—C16115.67 (11)
C3—C2—C1122.35 (11)O3—C11—C12122.82 (11)
C10—C2—C1121.25 (11)C16—C11—C12121.51 (11)
C4—C3—C2119.96 (11)C11—C12—C13118.32 (12)
C4—C3—H3120.0C11—C12—C1120.13 (11)
C2—C3—H3120.0C13—C12—C1121.55 (12)
C3—C4—C9118.78 (10)C14—C13—C12120.39 (13)
C3—C4—C5120.42 (11)C14—C13—H13119.8
C9—C4—C5120.79 (10)C12—C13—H13119.8
O2—C5—C4120.40 (11)C13—C14—C15120.18 (12)
O2—C5—C6121.68 (11)C13—C14—H14119.9
C4—C5—C6117.90 (11)C15—C14—H14119.9
C5—C6—C7115.45 (10)C16—C15—C14120.73 (12)
C5—C6—H6A108.4C16—C15—H15119.6
C7—C6—H6A108.4C14—C15—H15119.6
C5—C6—H6B108.4C15—C16—C11118.85 (13)
C7—C6—H6B108.4C15—C16—H16120.6
H6A—C6—H6B107.5C11—C16—H16120.6
C18—C7—C6110.08 (12)C7—C17—H17A109.5
C18—C7—C17109.31 (11)C7—C17—H17B109.5
C6—C7—C17109.11 (11)H17A—C17—H17B109.5
C18—C7—C8110.61 (11)C7—C17—H17C109.5
C6—C7—C8108.18 (11)H17A—C17—H17C109.5
C17—C7—C8109.53 (11)H17B—C17—H17C109.5
C9—C8—C7113.02 (11)C7—C18—H18A109.5
C9—C8—H8A109.0C7—C18—H18B109.5
C7—C8—H8A109.0H18A—C18—H18B109.5
C9—C8—H8B109.0C7—C18—H18C109.5
C7—C8—H8B109.0H18A—C18—H18C109.5
H8A—C8—H8B107.8H18B—C18—H18C109.5
N1—C9—C4122.22 (11)C10—N1—C9117.23 (10)
N1—C9—C8117.88 (11)C10—O3—C11119.42 (10)
C4—C9—C8119.90 (11)
O1—C1—C2—C33.61 (19)C1—C2—C10—N1178.92 (10)
C12—C1—C2—C3176.04 (10)C3—C2—C10—O3177.77 (10)
O1—C1—C2—C10176.52 (12)C1—C2—C10—O32.11 (18)
C12—C1—C2—C103.83 (16)O3—C11—C12—C13178.89 (10)
C10—C2—C3—C40.61 (16)C16—C11—C12—C131.16 (18)
C1—C2—C3—C4179.27 (10)O3—C11—C12—C12.24 (18)
C2—C3—C4—C91.67 (17)C16—C11—C12—C1177.71 (11)
C2—C3—C4—C5178.27 (10)O1—C1—C12—C11178.63 (12)
C3—C4—C5—O26.06 (18)C2—C1—C12—C111.73 (16)
C9—C4—C5—O2174.00 (12)O1—C1—C12—C132.54 (19)
C3—C4—C5—C6175.48 (10)C2—C1—C12—C13177.10 (10)
C9—C4—C5—C64.47 (17)C11—C12—C13—C141.21 (19)
O2—C5—C6—C7159.80 (13)C1—C12—C13—C14177.64 (11)
C4—C5—C6—C721.76 (17)C12—C13—C14—C150.5 (2)
C5—C6—C7—C1870.62 (14)C13—C14—C15—C160.2 (2)
C5—C6—C7—C17169.43 (11)C14—C15—C16—C110.3 (2)
C5—C6—C7—C850.34 (15)O3—C11—C16—C15179.63 (10)
C18—C7—C8—C965.43 (15)C12—C11—C16—C150.42 (19)
C6—C7—C8—C955.20 (15)O3—C10—N1—C9177.28 (10)
C17—C7—C8—C9174.03 (12)C2—C10—N1—C91.78 (18)
C3—C4—C9—N11.11 (18)C4—C9—N1—C100.57 (18)
C5—C4—C9—N1178.84 (10)C8—C9—N1—C10179.47 (11)
C3—C4—C9—C8178.85 (11)N1—C10—O3—C11177.09 (9)
C5—C4—C9—C81.21 (17)C2—C10—O3—C112.00 (17)
C7—C8—C9—N1147.69 (12)C16—C11—O3—C10175.71 (10)
C7—C8—C9—C432.35 (17)C12—C11—O3—C104.23 (17)
C3—C2—C10—N11.20 (18)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C15—H15···O2i0.932.433.250 (2)147
Symmetry code: (i) x1, y+1, z1.

Experimental details

Crystal data
Chemical formulaC18H15NO3
Mr293.31
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)7.4426 (6), 10.5117 (9), 10.6887 (9)
α, β, γ (°)60.939 (4), 88.107 (5), 77.546 (5)
V3)711.22 (10)
Z2
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.30 × 0.25 × 0.20
Data collection
DiffractometerBruker SMART APEXII area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.972, 0.982
No. of measured, independent and
observed [I > 2σ(I)] reflections
10655, 2949, 2427
Rint0.031
(sin θ/λ)max1)0.628
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.118, 1.05
No. of reflections2949
No. of parameters201
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.17, 0.22

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 2012), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C15—H15···O2i0.932.433.250 (2)147
Symmetry code: (i) x1, y+1, z1.
 

Acknowledgements

The authors thank the TBI X-ray facility, CAS in Crystallography and Biophysics, University of Madras, India, for the data collection. TS also thanks the DST for an Inspire fellowship.

References

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