organic compounds
1-Methyl-3-(2-methylphenyl)-3,3a,4,9b-tetrahydro-1H-chromeno[4,3-c][1,2]oxazole-3a-carbonitrile
aDepartment of Physics, RKM Vivekananda College (Autonomous), Chennai 600 004, India, and bDepartment of Organic Chemistry, University of Madras, Maraimalai Campus, Chennai 600 025, India
*Correspondence e-mail: ksethusankar@yahoo.co.in
In the title compound, C19H18N2O2, the five-membered isoxazole ring adopts an and the deviation of the N atom from the mean plane of the isoxazole ring is −0.3256 (11) Å. The pyran ring adopts a half-chair conformation. The isoxazole ring forms dihedral angles of 44.07 (7) and 84.23 (7)° with the pyran and methylbenzene rings, respectively. The molecular structure is stabilized by weak C—H⋯π interactions.
Related literature
For the synthesis of the title compound, see: Bakthadoss & Murugan (2010). For the biological and pharmacological activities of isoxazole derivatives, see: Hu et al. (2004); Lin et al. (1996); Rozman et al. (2002). For a related structure, see: Swaminathan et al. (2011). For puckering amplitudes, see: Cremer & Pople (1975).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: APEX2 (Bruker, 2004); cell SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009).
Supporting information
10.1107/S1600536811009378/pv2397sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536811009378/pv2397Isup2.hkl
A mixture of (E)-2-((2-formylphenoxy) methyl) -3-o-tolylacrylonitrile (1.0 mmol), N-methylhydroxylamine hydrochloride (1.1 mmol), pyridine (0.24 ml, 3 mmol) and ethanol (5 ml) were placed in a round bottom flask and refluxed for 6 h. After completion of the reaction as indicated by TLC, the reaction mixture was concentrated under reduced pressure. The crude product was diluted with water (10 ml) and dil HCl (5 ml) and extracted with ethylacetate (20 ml). The organic layer was washed with brine solution (10 ml) and concetrated. The crude product was purified by
to provide the pure title compound, as a colourless solid. Crystals of the title compound were grown from its solution in methanol by slow evaporation at room temperature.Hydrogen atoms were placed in calculated positions with C—H = 0.93, 0.96, 0.97 and 0.98 Å for aryl, methyl, methylene and methyne type H-atoms, respectively, and refined in riding model with fixed isotropic displacement parameters: Uiso(H) = 1.5 Ueq(methyl-C) and Uiso(H) = 1.2 Ueq(the rest of the C atoms).
Data collection: APEX2 (Bruker, 2004); cell
APEX2 (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).C19H18N2O2 | F(000) = 648 |
Mr = 306.35 | Dx = 1.278 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -p 2yn | Cell parameters from 5936 reflections |
a = 11.0120 (4) Å | θ = 1.0–25° |
b = 13.0368 (4) Å | µ = 0.08 mm−1 |
c = 11.1977 (3) Å | T = 293 K |
β = 97.836 (2)° | Block, colourless |
V = 1592.54 (9) Å3 | 0.30 × 0.25 × 0.20 mm |
Z = 4 |
Bruker Kappa APEXII CCD diffractometer | 3084 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.035 |
Graphite monochromator | θmax = 33.1°, θmin = 2.4° |
ω scans | h = −15→16 |
23069 measured reflections | k = −18→19 |
5936 independent reflections | l = −14→17 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.051 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.148 | H-atom parameters constrained |
S = 1.01 | w = 1/[σ2(Fo2) + (0.0684P)2 + 0.0556P] where P = (Fo2 + 2Fc2)/3 |
5936 reflections | (Δ/σ)max < 0.001 |
210 parameters | Δρmax = 0.18 e Å−3 |
0 restraints | Δρmin = −0.21 e Å−3 |
C19H18N2O2 | V = 1592.54 (9) Å3 |
Mr = 306.35 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 11.0120 (4) Å | µ = 0.08 mm−1 |
b = 13.0368 (4) Å | T = 293 K |
c = 11.1977 (3) Å | 0.30 × 0.25 × 0.20 mm |
β = 97.836 (2)° |
Bruker Kappa APEXII CCD diffractometer | 3084 reflections with I > 2σ(I) |
23069 measured reflections | Rint = 0.035 |
5936 independent reflections |
R[F2 > 2σ(F2)] = 0.051 | 0 restraints |
wR(F2) = 0.148 | H-atom parameters constrained |
S = 1.01 | Δρmax = 0.18 e Å−3 |
5936 reflections | Δρmin = −0.21 e Å−3 |
210 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.38107 (11) | 0.12807 (10) | 0.10789 (11) | 0.0446 (3) | |
C2 | 0.43271 (13) | 0.21739 (11) | 0.15852 (13) | 0.0582 (4) | |
H2 | 0.4706 | 0.2178 | 0.2380 | 0.070* | |
C3 | 0.42782 (15) | 0.30530 (12) | 0.09094 (15) | 0.0654 (4) | |
H3 | 0.4635 | 0.3652 | 0.1245 | 0.078* | |
C4 | 0.37052 (14) | 0.30563 (12) | −0.02619 (15) | 0.0640 (4) | |
H4 | 0.3685 | 0.3653 | −0.0720 | 0.077* | |
C5 | 0.31626 (13) | 0.21749 (10) | −0.07520 (13) | 0.0536 (3) | |
H5 | 0.2754 | 0.2187 | −0.1535 | 0.064* | |
C6 | 0.32143 (11) | 0.12627 (9) | −0.00950 (10) | 0.0425 (3) | |
C7 | 0.25834 (11) | 0.03122 (9) | −0.06218 (10) | 0.0407 (3) | |
H7 | 0.1745 | 0.0473 | −0.0987 | 0.049* | |
C8 | 0.25759 (10) | −0.05625 (9) | 0.02964 (10) | 0.0396 (3) | |
C9 | 0.37624 (12) | −0.05094 (10) | 0.11822 (11) | 0.0458 (3) | |
H9A | 0.3776 | −0.1068 | 0.1756 | 0.055* | |
H9B | 0.4458 | −0.0593 | 0.0744 | 0.055* | |
C10 | 0.25780 (11) | −0.15460 (10) | −0.05147 (10) | 0.0448 (3) | |
H10 | 0.3344 | −0.1923 | −0.0288 | 0.054* | |
C11 | 0.15148 (11) | −0.22621 (9) | −0.04883 (10) | 0.0430 (3) | |
C12 | 0.03836 (12) | −0.19982 (11) | −0.11130 (12) | 0.0528 (3) | |
H12 | 0.0313 | −0.1411 | −0.1589 | 0.063* | |
C13 | −0.06361 (13) | −0.25916 (12) | −0.10388 (13) | 0.0577 (4) | |
H13 | −0.1390 | −0.2407 | −0.1462 | 0.069* | |
C14 | −0.05336 (13) | −0.34544 (11) | −0.03398 (13) | 0.0571 (4) | |
H14 | −0.1221 | −0.3854 | −0.0278 | 0.069* | |
C15 | 0.05804 (14) | −0.37299 (10) | 0.02683 (12) | 0.0544 (3) | |
H15 | 0.0638 | −0.4322 | 0.0735 | 0.065* | |
C16 | 0.16284 (12) | −0.31509 (10) | 0.02085 (10) | 0.0458 (3) | |
C17 | 0.28229 (15) | −0.35091 (13) | 0.08907 (14) | 0.0714 (4) | |
H17A | 0.3372 | −0.3698 | 0.0331 | 0.107* | |
H17B | 0.2679 | −0.4092 | 0.1376 | 0.107* | |
H17C | 0.3181 | −0.2966 | 0.1400 | 0.107* | |
C18 | 0.31258 (15) | 0.02789 (12) | −0.26883 (11) | 0.0624 (4) | |
H18A | 0.3441 | −0.0171 | −0.3251 | 0.094* | |
H18B | 0.3574 | 0.0912 | −0.2641 | 0.094* | |
H18C | 0.2275 | 0.0413 | −0.2953 | 0.094* | |
C19 | 0.15272 (11) | −0.05003 (9) | 0.09694 (11) | 0.0439 (3) | |
N1 | 0.32585 (9) | −0.02011 (8) | −0.15097 (8) | 0.0464 (3) | |
N2 | 0.07493 (11) | −0.04521 (10) | 0.15340 (10) | 0.0598 (3) | |
O1 | 0.38708 (8) | 0.04332 (7) | 0.18095 (7) | 0.0501 (2) | |
O2 | 0.25538 (9) | −0.11520 (7) | −0.17000 (7) | 0.0540 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0477 (6) | 0.0468 (7) | 0.0411 (6) | −0.0039 (5) | 0.0120 (5) | −0.0003 (5) |
C2 | 0.0646 (8) | 0.0602 (9) | 0.0508 (7) | −0.0107 (7) | 0.0116 (6) | −0.0100 (7) |
C3 | 0.0768 (10) | 0.0492 (9) | 0.0737 (10) | −0.0142 (7) | 0.0224 (8) | −0.0106 (8) |
C4 | 0.0764 (10) | 0.0434 (8) | 0.0756 (10) | −0.0011 (7) | 0.0229 (8) | 0.0065 (7) |
C5 | 0.0592 (8) | 0.0497 (8) | 0.0530 (7) | 0.0026 (6) | 0.0116 (6) | 0.0084 (6) |
C6 | 0.0446 (6) | 0.0427 (7) | 0.0416 (6) | 0.0008 (5) | 0.0116 (5) | 0.0013 (5) |
C7 | 0.0426 (6) | 0.0460 (7) | 0.0341 (5) | −0.0010 (5) | 0.0071 (4) | 0.0045 (5) |
C8 | 0.0436 (6) | 0.0430 (7) | 0.0332 (5) | −0.0024 (5) | 0.0089 (4) | 0.0016 (5) |
C9 | 0.0518 (7) | 0.0487 (7) | 0.0370 (6) | −0.0009 (6) | 0.0060 (5) | 0.0052 (5) |
C10 | 0.0519 (7) | 0.0451 (7) | 0.0392 (6) | 0.0005 (5) | 0.0128 (5) | −0.0001 (5) |
C11 | 0.0529 (7) | 0.0397 (7) | 0.0379 (5) | −0.0008 (5) | 0.0121 (5) | −0.0041 (5) |
C12 | 0.0604 (8) | 0.0440 (7) | 0.0544 (7) | 0.0017 (6) | 0.0087 (6) | 0.0031 (6) |
C13 | 0.0516 (7) | 0.0597 (9) | 0.0617 (8) | −0.0006 (6) | 0.0072 (6) | −0.0070 (7) |
C14 | 0.0609 (8) | 0.0535 (8) | 0.0600 (8) | −0.0130 (7) | 0.0192 (7) | −0.0093 (7) |
C15 | 0.0768 (9) | 0.0427 (7) | 0.0461 (7) | −0.0094 (6) | 0.0168 (6) | −0.0025 (6) |
C16 | 0.0623 (8) | 0.0398 (7) | 0.0360 (6) | −0.0005 (6) | 0.0098 (5) | −0.0036 (5) |
C17 | 0.0772 (10) | 0.0690 (11) | 0.0641 (9) | −0.0002 (8) | −0.0049 (8) | 0.0154 (8) |
C18 | 0.0810 (10) | 0.0714 (10) | 0.0372 (6) | −0.0130 (8) | 0.0161 (6) | 0.0050 (6) |
C19 | 0.0513 (7) | 0.0423 (7) | 0.0394 (6) | −0.0030 (5) | 0.0102 (5) | 0.0016 (5) |
N1 | 0.0557 (6) | 0.0498 (6) | 0.0361 (5) | −0.0091 (5) | 0.0146 (4) | 0.0002 (4) |
N2 | 0.0639 (7) | 0.0652 (8) | 0.0551 (7) | 0.0023 (6) | 0.0249 (6) | 0.0060 (6) |
O1 | 0.0622 (5) | 0.0532 (6) | 0.0340 (4) | −0.0076 (4) | 0.0040 (4) | 0.0004 (4) |
O2 | 0.0737 (6) | 0.0535 (6) | 0.0374 (4) | −0.0161 (4) | 0.0166 (4) | −0.0045 (4) |
C1—O1 | 1.3710 (14) | C10—C11 | 1.5008 (17) |
C1—C2 | 1.3830 (18) | C10—H10 | 0.9800 |
C1—C6 | 1.3872 (17) | C11—C12 | 1.3864 (18) |
C2—C3 | 1.370 (2) | C11—C16 | 1.3928 (17) |
C2—H2 | 0.9300 | C12—C13 | 1.3754 (19) |
C3—C4 | 1.376 (2) | C12—H12 | 0.9300 |
C3—H3 | 0.9300 | C13—C14 | 1.366 (2) |
C4—C5 | 1.374 (2) | C13—H13 | 0.9300 |
C4—H4 | 0.9300 | C14—C15 | 1.367 (2) |
C5—C6 | 1.3954 (17) | C14—H14 | 0.9300 |
C5—H5 | 0.9300 | C15—C16 | 1.3882 (18) |
C6—C7 | 1.5015 (17) | C15—H15 | 0.9300 |
C7—N1 | 1.4800 (15) | C16—C17 | 1.5027 (19) |
C7—C8 | 1.5363 (16) | C17—H17A | 0.9600 |
C7—H7 | 0.9800 | C17—H17B | 0.9600 |
C8—C19 | 1.4647 (16) | C17—H17C | 0.9600 |
C8—C9 | 1.5305 (16) | C18—N1 | 1.4498 (16) |
C8—C10 | 1.5715 (17) | C18—H18A | 0.9600 |
C9—O1 | 1.4124 (15) | C18—H18B | 0.9600 |
C9—H9A | 0.9700 | C18—H18C | 0.9600 |
C9—H9B | 0.9700 | C19—N2 | 1.1336 (16) |
C10—O2 | 1.4201 (14) | N1—O2 | 1.4626 (13) |
O1—C1—C2 | 116.76 (11) | O2—C10—H10 | 109.2 |
O1—C1—C6 | 122.00 (11) | C11—C10—H10 | 109.2 |
C2—C1—C6 | 121.18 (12) | C8—C10—H10 | 109.2 |
C3—C2—C1 | 119.65 (14) | C12—C11—C16 | 119.67 (11) |
C3—C2—H2 | 120.2 | C12—C11—C10 | 119.03 (11) |
C1—C2—H2 | 120.2 | C16—C11—C10 | 121.18 (11) |
C2—C3—C4 | 120.50 (14) | C13—C12—C11 | 120.98 (13) |
C2—C3—H3 | 119.8 | C13—C12—H12 | 119.5 |
C4—C3—H3 | 119.8 | C11—C12—H12 | 119.5 |
C5—C4—C3 | 119.73 (14) | C14—C13—C12 | 119.56 (13) |
C5—C4—H4 | 120.1 | C14—C13—H13 | 120.2 |
C3—C4—H4 | 120.1 | C12—C13—H13 | 120.2 |
C4—C5—C6 | 121.18 (13) | C13—C14—C15 | 120.00 (13) |
C4—C5—H5 | 119.4 | C13—C14—H14 | 120.0 |
C6—C5—H5 | 119.4 | C15—C14—H14 | 120.0 |
C1—C6—C5 | 117.72 (12) | C14—C15—C16 | 121.90 (13) |
C1—C6—C7 | 121.34 (11) | C14—C15—H15 | 119.1 |
C5—C6—C7 | 120.85 (11) | C16—C15—H15 | 119.1 |
N1—C7—C6 | 112.90 (9) | C15—C16—C11 | 117.88 (12) |
N1—C7—C8 | 99.38 (9) | C15—C16—C17 | 118.83 (12) |
C6—C7—C8 | 113.21 (9) | C11—C16—C17 | 123.28 (12) |
N1—C7—H7 | 110.3 | C16—C17—H17A | 109.5 |
C6—C7—H7 | 110.3 | C16—C17—H17B | 109.5 |
C8—C7—H7 | 110.3 | H17A—C17—H17B | 109.5 |
C19—C8—C9 | 109.11 (9) | C16—C17—H17C | 109.5 |
C19—C8—C7 | 112.33 (9) | H17A—C17—H17C | 109.5 |
C9—C8—C7 | 108.55 (9) | H17B—C17—H17C | 109.5 |
C19—C8—C10 | 113.95 (9) | N1—C18—H18A | 109.5 |
C9—C8—C10 | 110.06 (10) | N1—C18—H18B | 109.5 |
C7—C8—C10 | 102.61 (9) | H18A—C18—H18B | 109.5 |
O1—C9—C8 | 111.62 (10) | N1—C18—H18C | 109.5 |
O1—C9—H9A | 109.3 | H18A—C18—H18C | 109.5 |
C8—C9—H9A | 109.3 | H18B—C18—H18C | 109.5 |
O1—C9—H9B | 109.3 | N2—C19—C8 | 177.11 (13) |
C8—C9—H9B | 109.3 | C18—N1—O2 | 104.33 (9) |
H9A—C9—H9B | 108.0 | C18—N1—C7 | 114.76 (11) |
O2—C10—C11 | 109.16 (10) | O2—N1—C7 | 100.14 (8) |
O2—C10—C8 | 104.11 (9) | C1—O1—C9 | 114.23 (9) |
C11—C10—C8 | 115.69 (9) | C10—O2—N1 | 103.20 (8) |
O1—C1—C2—C3 | −178.84 (12) | C9—C8—C10—C11 | 123.40 (11) |
C6—C1—C2—C3 | −1.6 (2) | C7—C8—C10—C11 | −121.21 (11) |
C1—C2—C3—C4 | 0.9 (2) | O2—C10—C11—C12 | −41.16 (15) |
C2—C3—C4—C5 | 0.9 (2) | C8—C10—C11—C12 | 75.80 (14) |
C3—C4—C5—C6 | −2.0 (2) | O2—C10—C11—C16 | 142.76 (11) |
O1—C1—C6—C5 | 177.60 (11) | C8—C10—C11—C16 | −100.28 (13) |
C2—C1—C6—C5 | 0.56 (18) | C16—C11—C12—C13 | 1.17 (19) |
O1—C1—C6—C7 | 0.98 (18) | C10—C11—C12—C13 | −174.97 (12) |
C2—C1—C6—C7 | −176.06 (11) | C11—C12—C13—C14 | 0.0 (2) |
C4—C5—C6—C1 | 1.29 (19) | C12—C13—C14—C15 | −0.8 (2) |
C4—C5—C6—C7 | 177.93 (12) | C13—C14—C15—C16 | 0.5 (2) |
C1—C6—C7—N1 | −106.66 (12) | C14—C15—C16—C11 | 0.60 (19) |
C5—C6—C7—N1 | 76.83 (14) | C14—C15—C16—C17 | −179.31 (13) |
C1—C6—C7—C8 | 5.29 (16) | C12—C11—C16—C15 | −1.42 (17) |
C5—C6—C7—C8 | −171.23 (10) | C10—C11—C16—C15 | 174.63 (11) |
N1—C7—C8—C19 | −152.86 (9) | C12—C11—C16—C17 | 178.48 (13) |
C6—C7—C8—C19 | 87.13 (12) | C10—C11—C16—C17 | −5.46 (18) |
N1—C7—C8—C9 | 86.40 (10) | C6—C7—N1—C18 | −77.73 (13) |
C6—C7—C8—C9 | −33.60 (13) | C8—C7—N1—C18 | 162.04 (10) |
N1—C7—C8—C10 | −30.08 (10) | C6—C7—N1—O2 | 171.21 (9) |
C6—C7—C8—C10 | −150.08 (10) | C8—C7—N1—O2 | 50.98 (10) |
C19—C8—C9—O1 | −62.50 (12) | C2—C1—O1—C9 | −157.77 (11) |
C7—C8—C9—O1 | 60.20 (12) | C6—C1—O1—C9 | 25.06 (16) |
C10—C8—C9—O1 | 171.77 (9) | C8—C9—O1—C1 | −56.41 (13) |
C19—C8—C10—O2 | 120.23 (10) | C11—C10—O2—N1 | 157.42 (9) |
C9—C8—C10—O2 | −116.84 (10) | C8—C10—O2—N1 | 33.34 (11) |
C7—C8—C10—O2 | −1.45 (11) | C18—N1—O2—C10 | −173.44 (10) |
C19—C8—C10—C11 | 0.47 (15) | C7—N1—O2—C10 | −54.44 (11) |
Cg1 is the centroid of the phenyl ring C11–C16. |
D—H···A | D—H | H···A | D···A | D—H···A |
C18—H18B···Cg1i | 0.96 | 2.99 | 3.6831 (16) | 130 |
Symmetry code: (i) −x+1/2, y+1/2, −z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C19H18N2O2 |
Mr | 306.35 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 293 |
a, b, c (Å) | 11.0120 (4), 13.0368 (4), 11.1977 (3) |
β (°) | 97.836 (2) |
V (Å3) | 1592.54 (9) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.30 × 0.25 × 0.20 |
Data collection | |
Diffractometer | Bruker Kappa APEXII CCD diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 23069, 5936, 3084 |
Rint | 0.035 |
(sin θ/λ)max (Å−1) | 0.769 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.051, 0.148, 1.01 |
No. of reflections | 5936 |
No. of parameters | 210 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.18, −0.21 |
Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).
Cg1 is the centroid of the phenyl ring C11–C16. |
D—H···A | D—H | H···A | D···A | D—H···A |
C18—H18B···Cg1i | 0.96 | 2.99 | 3.6831 (16) | 130 |
Symmetry code: (i) −x+1/2, y+1/2, −z−1/2. |
Acknowledgements
K. Swaminathan and K. Sethusankar thank Dr Babu Varghese, SAIF, IIT, Chennai, India, for the
data collection.References
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The title compound is an angularly substituted fused tricyclic chromenoisoxazolidine framework, synthesized using Baylis-Hillman derivatives through in situ formation of nitrones followed by an intramolecular (3 + 2) dipolar cycloaddition reaction sequence (Bakthadoss & Murugan, 2010). It is well known that benzopyran and isoxazolidine derivatives possess interesting biological and pharmacological activities (Lin et al., 1996; Hu et al., 2004). Leflunomide is an isoxazole drug used for the treatment of rheumatoid arthritis (Rozman et al., 2002).
The title compound (Fig. 1) comprises a chromenoisoxazole ring system attached to a methylbenzene ring and a carbonitrile group. The isoxazole ring (N1/O2/C7/C8/C10) adopts an N1 envelope conformation with N1 -0.3256 (11) Å out of the plane formed by the rest of the ring atoms. The isoxazole ring is inclined at 84.23 (7)° with respect to the mean-plane formed by methylbenzene ring (C11—C16). The pyran ring (O1/C1/C6-C9) adopts a half-chair conformation with puckering amplitudes (Cremer & Pople, 1975): Q = 0.4852 (13) Å, θ = 127.2 (2)° and ϕ = 107.9 (2)°. The title compound exhibits structural similarities with a reported structure (Swaminathan et al., 2011). The molecular structure of the title compound is stabilized by rather weak C18—H18B···π interactions involving the centroid (Cg1) of phenyl ring C11–C16 (Table 1).