organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

3-(2-Methyl­phen­yl)-3a,4-di­hydro-3H-chromeno[4,3-c]isoxazole-3a-carbo­nitrile

aDepartment of Physics, Presidency College (Autonomous), Chennai 600 005, India, and bDepartment of Organic Chemistry, University of Madras, Chennai 600 025, India
*Correspondence e-mail: aravindhanpresidency@gmail.com

(Received 16 December 2012; accepted 22 December 2012; online 4 January 2013)

In the title compound, C18H14N2O2, the pyran ring of the chromeno ring system has a half-chair conformation, and the dihedral angle between its mean plane and the benzene ring is 5.3 (2)°. The isoxazole ring forms a dihedral angle of 74.6 (2)° with the attached benzene ring and is inclined to the mean plane of the chromeno ring system by 15.06 (19)°. In the crystal, there are no significant inter­molecular inter­actions.

Related literature

For the biological importance of 4H-chromene derivatives, see: Cai (2007[Cai, S. X. (2007). Recent Patents Anticancer Drug Discov. 2, 79-101.], 2008[Cai, S. X. (2008). Bioorg. Med. Chem. Lett. 18, 603-607.]); Cai et al. (2006[Cai, S. X., Drewe, J. & Kasibhatla, S. (2006). Curr. Med. Chem. 13, 2627-2644.]); Gabor (1988[Gabor, M. (1988). The Pharmacology of Benzopyrone Derivatives and Related Compounds, pp. 91-126. Budapest: Akademiai Kiado.]); Brooks (1998[Brooks, G. T. (1998). Pestic. Sci. 22, 41-50.]); Valenti et al. (1993[Valenti, P., Da Re, P., Rampa, A., Montanari, P., Carrara, M. & Cima, L. (1993). Anticancer Drug. Des. 8, 349-360.]); Hyana & Saimoto (1987[Hyana, T. & Saimoto, H. (1987). Jpn Patent JP 621 812 768.]); Tang et al. (2007[Tang, Q.-G., Wu, W.-Y., He, W., Sun, H.-S. & Guo, C. (2007). Acta Cryst. E63, o1437-o1438.]). For related structures, see: Gangadharan et al. (2011[Gangadharan, R., SethuSankar, K., Murugan, G. & Bakthadoss, M. (2011). Acta Cryst. E67, o942.]); Swaminathan et al. (2011[Swaminathan, K., Sethusankar, K., Murugan, G. & Bakthadoss, M. (2011). Acta Cryst. E67, o905.]).

[Scheme 1]

Experimental

Crystal data
  • C18H14N2O2

  • Mr = 290.31

  • Orthorhombic, P c a 21

  • a = 19.326 (3) Å

  • b = 10.7866 (17) Å

  • c = 6.9072 (11) Å

  • V = 1439.9 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 298 K

  • 0.35 × 0.25 × 0.15 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.970, Tmax = 0.987

  • 4742 measured reflections

  • 1750 independent reflections

  • 1100 reflections with I > 2σ(I)

  • Rint = 0.047

Refinement
  • R[F2 > 2σ(F2)] = 0.059

  • wR(F2) = 0.146

  • S = 1.09

  • 1750 reflections

  • 200 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.17 e Å−3

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

4H-Chromenes are biologically important compounds used as synthetic ligands for drug designing and discovery process. They exhibit numerous biological and pharmacological properties such as anti-viral, anti-fungal, anti-inflammatory, anti- diabetic, cardionthonic, anti anaphylactic and anti-cancer activity (Cai, 2008; Cai, 2007; Cai et al., 2006; Gabor, 1988; Brooks, 1998; Valenti et al., 1993; Hyana & Saimoto, 1987; Tang et al., 2007). We report herein on the synthesis of a new chromeno compound and its crystal structure.

The molecular structure of the title molecule is illustrated in Fig. 1. In the chromeno ring system, the dihedral angle between the mean plane of the pyran ring, which has a half-chair conformation, and the benzene ring is 5.3 (2)°. The dihedral angle between the mean plane of the chromeno ring system and isoxazole ring is 15.06 (19)°. The isoxazole ring also forms a dihedral angle of 74.6 (2)° with the the benzene ring (C11—C16). The geometric parameters of the title molecule agree well with those reported for closely related structures (Gangadharan et al., 2011; Swaminathan et al., 2011).

In the crystal, there are no significant intermolecular interactions.

Related literature top

For the biological importance of 4H-chromene derivatives, see: Cai (2007, 2008); Cai et al. (2006); Gabor (1988); Brooks (1998); Valenti et al. (1993); Hyana & Saimoto (1987); Tang et al. (2007). For related structures, see: Gangadharan et al. (2011); Swaminathan et al. (2011).

Experimental top

NCS (4 mmol) was added pinch wise over 3h to a solution of (E)-2-((2-((E)-(hydroxyimino)methyl)phenoxy)methyl)-3-o-tolylacrylonitrile(2 mmol) in CCl4 at 273 - 283 K. After Et3N (4 mmol) was added to the reaction mixture which was stirred at room temperature for 2 h. After completion of the reaction, the mixture was evaporated under reduced pressure and the resulting crude mass was diluted with water (15 ml) and extracted with ethyl acetate (3 × 15 ml). The combined organic layers washed with brine (2 × 10 ml) and dried over anhydrous Na2SO4. The organic layer was evaporated and purified by column chromatography (silica gel 60–120 mesh; 7% EtOAc in hexanes) to provide the desired title product as a colourless solid. 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

All the hydrogen atoms were placed in calculated positions and refined as riding atoms: C—H = 0.93–0.98 Å with Uiso(H) = 1.5Ueq(C) for methyl group and = 1.2Ueq(C) for other groups. In the final cycles of refinement, in the absence of significant anomalous scattering effects, Friedel pairs were merged and Δf " set to zero.

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, with the atom labeling. Displacement ellipsoids are drawn at the 30% probability level.
3-(2-Methylphenyl)-3a,4-dihydro-3H-chromeno[4,3-c]isoxazole-3a- carbonitrile top
Crystal data top
C18H14N2O2F(000) = 608
Mr = 290.31Dx = 1.339 Mg m3
Orthorhombic, Pca21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2acCell parameters from 1750 reflections
a = 19.326 (3) Åθ = 1.9–27.7°
b = 10.7866 (17) ŵ = 0.09 mm1
c = 6.9072 (11) ÅT = 298 K
V = 1439.9 (4) Å3Orthorhombic, colourless
Z = 40.35 × 0.25 × 0.15 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
1750 independent reflections
Radiation source: fine-focus sealed tube1100 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.047
ω and ϕ scansθmax = 27.7°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 2425
Tmin = 0.970, Tmax = 0.987k = 1013
4742 measured reflectionsl = 86
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)] = 0.059Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.146H-atom parameters constrained
S = 1.09 w = 1/[σ2(Fo2) + (0.0456P)2 + 0.5663P]
where P = (Fo2 + 2Fc2)/3
1750 reflections(Δ/σ)max < 0.001
200 parametersΔρmax = 0.21 e Å3
1 restraintΔρmin = 0.17 e Å3
Crystal data top
C18H14N2O2V = 1439.9 (4) Å3
Mr = 290.31Z = 4
Orthorhombic, Pca21Mo Kα radiation
a = 19.326 (3) ŵ = 0.09 mm1
b = 10.7866 (17) ÅT = 298 K
c = 6.9072 (11) Å0.35 × 0.25 × 0.15 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
1750 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
1100 reflections with I > 2σ(I)
Tmin = 0.970, Tmax = 0.987Rint = 0.047
4742 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0591 restraint
wR(F2) = 0.146H-atom parameters constrained
S = 1.09Δρmax = 0.21 e Å3
1750 reflectionsΔρmin = 0.17 e Å3
200 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
C10.8559 (2)0.2941 (4)0.6812 (9)0.0493 (12)
C20.8529 (2)0.4218 (5)0.6834 (12)0.0659 (16)
H20.86390.46670.57270.079*
C30.8336 (3)0.4824 (5)0.8491 (13)0.0725 (18)
H30.83110.56850.85020.087*
C40.8177 (2)0.4155 (6)1.0168 (11)0.0717 (18)
H40.80530.45721.12940.086*
C50.8204 (2)0.2907 (5)1.0155 (9)0.0597 (14)
H50.80930.24701.12740.072*
C60.8397 (2)0.2254 (5)0.8478 (8)0.0494 (13)
C70.84595 (19)0.0931 (5)0.8391 (7)0.0421 (12)
C80.8522 (2)0.0964 (4)0.6809 (8)0.0457 (11)
H80.80930.10130.60580.055*
C90.88122 (19)0.0358 (4)0.6634 (7)0.0384 (10)
C100.8602 (2)0.1104 (5)0.4876 (8)0.0482 (12)
H10A0.81090.10070.46590.058*
H10B0.88420.07890.37460.058*
C110.8981 (2)0.2017 (4)0.6220 (7)0.0434 (12)
C120.9523 (2)0.2369 (4)0.7453 (9)0.0558 (14)
H120.95720.19880.86530.067*
C130.9984 (2)0.3274 (5)0.6900 (11)0.0674 (17)
H131.03370.35200.77330.081*
C140.9919 (3)0.3817 (5)0.5095 (13)0.0744 (19)
H141.02390.44060.46860.089*
C150.9383 (3)0.3483 (5)0.3917 (9)0.0618 (14)
H150.93410.38650.27160.074*
C160.8901 (2)0.2600 (4)0.4442 (8)0.0474 (12)
C170.8323 (3)0.2283 (5)0.3092 (9)0.0668 (15)
H17A0.78880.24250.37260.100*
H17B0.83570.14260.27260.100*
H17C0.83530.27930.19570.100*
C180.9575 (2)0.0430 (4)0.6899 (7)0.0412 (10)
N10.82063 (19)0.0141 (4)0.9557 (7)0.0556 (11)
N21.01564 (18)0.0484 (4)0.7066 (7)0.0570 (11)
O10.87563 (16)0.2367 (3)0.5112 (6)0.0556 (9)
O20.83494 (17)0.1062 (3)0.8863 (5)0.0582 (9)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.038 (2)0.057 (3)0.054 (3)0.001 (2)0.006 (2)0.002 (3)
C20.054 (3)0.056 (4)0.088 (5)0.003 (2)0.001 (3)0.021 (4)
C30.059 (3)0.048 (3)0.110 (6)0.003 (2)0.006 (3)0.005 (4)
C40.051 (3)0.083 (4)0.081 (5)0.001 (3)0.006 (3)0.025 (5)
C50.050 (3)0.075 (4)0.055 (4)0.008 (3)0.008 (3)0.005 (3)
C60.034 (2)0.069 (3)0.046 (3)0.002 (2)0.003 (2)0.002 (3)
C70.035 (2)0.058 (3)0.033 (3)0.004 (2)0.0013 (19)0.009 (3)
C80.043 (2)0.056 (3)0.038 (3)0.003 (2)0.004 (2)0.005 (3)
C90.042 (2)0.045 (2)0.029 (2)0.0030 (18)0.0034 (19)0.007 (2)
C100.047 (2)0.062 (3)0.036 (3)0.001 (2)0.004 (2)0.009 (3)
C110.041 (2)0.042 (3)0.047 (3)0.0072 (19)0.001 (2)0.015 (2)
C120.054 (3)0.055 (3)0.057 (4)0.010 (2)0.014 (2)0.004 (3)
C130.050 (3)0.056 (3)0.097 (5)0.001 (2)0.019 (3)0.012 (4)
C140.055 (3)0.062 (4)0.106 (6)0.001 (2)0.003 (3)0.001 (4)
C150.065 (3)0.064 (3)0.057 (4)0.008 (3)0.005 (3)0.003 (3)
C160.051 (2)0.044 (3)0.047 (3)0.009 (2)0.001 (2)0.010 (3)
C170.087 (4)0.068 (4)0.045 (4)0.005 (3)0.015 (3)0.005 (3)
C180.044 (2)0.049 (3)0.030 (2)0.0022 (19)0.007 (2)0.004 (2)
N10.052 (2)0.071 (3)0.043 (3)0.003 (2)0.0102 (18)0.008 (2)
N20.041 (2)0.072 (3)0.057 (3)0.0055 (18)0.001 (2)0.007 (3)
O10.068 (2)0.053 (2)0.045 (2)0.0031 (17)0.0091 (18)0.0161 (19)
O20.070 (2)0.062 (2)0.042 (2)0.0082 (16)0.0097 (17)0.012 (2)
Geometric parameters (Å, º) top
C1—C21.379 (7)C10—O11.405 (6)
C1—O11.381 (7)C10—H10A0.9700
C1—C61.404 (7)C10—H10B0.9700
C2—C31.370 (10)C11—C161.388 (7)
C2—H20.9300C11—C121.403 (6)
C3—C41.399 (9)C12—C131.376 (7)
C3—H30.9300C12—H120.9300
C4—C51.347 (8)C13—C141.383 (10)
C4—H40.9300C13—H130.9300
C5—C61.406 (7)C14—C151.365 (8)
C5—H50.9300C14—H140.9300
C6—C71.433 (7)C15—C161.381 (7)
C7—N11.271 (6)C15—H150.9300
C7—C91.523 (6)C16—C171.495 (7)
C8—O21.461 (6)C17—H17A0.9600
C8—C111.497 (6)C17—H17B0.9600
C8—C91.537 (6)C17—H17C0.9600
C8—H80.9800C18—N21.131 (5)
C9—C181.487 (5)N1—O21.410 (5)
C9—C101.512 (7)
C2—C1—O1118.0 (5)O1—C10—H10A109.3
C2—C1—C6120.6 (6)C9—C10—H10A109.3
O1—C1—C6121.5 (4)O1—C10—H10B109.3
C3—C2—C1119.8 (6)C9—C10—H10B109.3
C3—C2—H2120.1H10A—C10—H10B108.0
C1—C2—H2120.1C16—C11—C12119.8 (4)
C2—C3—C4120.4 (5)C16—C11—C8121.2 (4)
C2—C3—H3119.8C12—C11—C8118.9 (5)
C4—C3—H3119.8C13—C12—C11120.5 (6)
C5—C4—C3120.1 (6)C13—C12—H12119.8
C5—C4—H4119.9C11—C12—H12119.8
C3—C4—H4119.9C12—C13—C14119.5 (5)
C4—C5—C6121.0 (6)C12—C13—H13120.3
C4—C5—H5119.5C14—C13—H13120.3
C6—C5—H5119.5C15—C14—C13119.6 (6)
C1—C6—C5118.0 (5)C15—C14—H14120.2
C1—C6—C7118.2 (5)C13—C14—H14120.2
C5—C6—C7123.7 (5)C14—C15—C16122.5 (6)
N1—C7—C6127.5 (4)C14—C15—H15118.7
N1—C7—C9113.8 (4)C16—C15—H15118.7
C6—C7—C9118.4 (4)C15—C16—C11118.0 (5)
O2—C8—C11110.1 (4)C15—C16—C17119.9 (5)
O2—C8—C9103.1 (4)C11—C16—C17122.1 (4)
C11—C8—C9117.8 (4)C16—C17—H17A109.5
O2—C8—H8108.5C16—C17—H17B109.5
C11—C8—H8108.5H17A—C17—H17B109.5
C9—C8—H8108.5C16—C17—H17C109.5
C18—C9—C10109.7 (3)H17A—C17—H17C109.5
C18—C9—C7108.9 (4)H17B—C17—H17C109.5
C10—C9—C7107.6 (3)N2—C18—C9178.8 (5)
C18—C9—C8113.6 (3)C7—N1—O2109.1 (4)
C10—C9—C8117.3 (4)C1—O1—C10118.3 (4)
C7—C9—C898.7 (4)N1—O2—C8107.9 (3)
O1—C10—C9111.5 (4)
O1—C1—C2—C3179.9 (4)C18—C9—C10—O162.9 (5)
C6—C1—C2—C30.4 (7)C7—C9—C10—O155.5 (4)
C1—C2—C3—C40.8 (8)C8—C9—C10—O1165.5 (4)
C2—C3—C4—C50.9 (8)O2—C8—C11—C16140.8 (4)
C3—C4—C5—C60.7 (7)C9—C8—C11—C16101.4 (5)
C2—C1—C6—C50.2 (6)O2—C8—C11—C1242.6 (5)
O1—C1—C6—C5179.7 (4)C9—C8—C11—C1275.2 (6)
C2—C1—C6—C7177.9 (4)C16—C11—C12—C131.1 (7)
O1—C1—C6—C71.5 (6)C8—C11—C12—C13175.5 (5)
C4—C5—C6—C10.3 (7)C11—C12—C13—C141.5 (8)
C4—C5—C6—C7177.7 (4)C12—C13—C14—C152.6 (8)
C1—C6—C7—N1163.8 (4)C13—C14—C15—C161.0 (9)
C5—C6—C7—N118.2 (7)C14—C15—C16—C111.5 (7)
C1—C6—C7—C910.4 (5)C14—C15—C16—C17179.5 (5)
C5—C6—C7—C9167.6 (4)C12—C11—C16—C152.6 (6)
N1—C7—C9—C18103.9 (4)C8—C11—C16—C15174.0 (4)
C6—C7—C9—C1881.1 (4)C12—C11—C16—C17178.5 (5)
N1—C7—C9—C10137.2 (4)C8—C11—C16—C175.0 (6)
C6—C7—C9—C1037.8 (5)C6—C7—N1—O2175.9 (4)
N1—C7—C9—C814.8 (5)C9—C7—N1—O21.4 (5)
C6—C7—C9—C8160.2 (4)C2—C1—O1—C10162.0 (4)
O2—C8—C9—C1891.3 (4)C6—C1—O1—C1018.6 (6)
C11—C8—C9—C1830.2 (7)C9—C10—O1—C148.4 (5)
O2—C8—C9—C10138.9 (4)C7—N1—O2—C818.6 (4)
C11—C8—C9—C1099.6 (5)C11—C8—O2—N1153.6 (3)
O2—C8—C9—C723.9 (4)C9—C8—O2—N127.1 (4)
C11—C8—C9—C7145.4 (4)

Experimental details

Crystal data
Chemical formulaC18H14N2O2
Mr290.31
Crystal system, space groupOrthorhombic, Pca21
Temperature (K)298
a, b, c (Å)19.326 (3), 10.7866 (17), 6.9072 (11)
V3)1439.9 (4)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.35 × 0.25 × 0.15
Data collection
DiffractometerBruker APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.970, 0.987
No. of measured, independent and
observed [I > 2σ(I)] reflections
4742, 1750, 1100
Rint0.047
(sin θ/λ)max1)0.653
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.059, 0.146, 1.09
No. of reflections1750
No. of parameters200
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.21, 0.17

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

 

Acknowledgements

GS and SA thank the UGC, India, for financial support. GS thanks the SAIF, IIT-Madras, for the instrumentation facility.

References

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