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Acta Crystallogr Sect E Struct Rep Online. 2009 April 1; 65(Pt 4): o806–o807.
Published online 2009 March 19. doi:  10.1107/S1600536809009350
PMCID: PMC2968888

Dimethyl cis-2-methyl-3-p-tolyl­isoxazolidine-4,5-dicarboxyl­ate

Abstract

In the mol­ecule of the title compound, C15H19NO5, the isoxazole ring adopts an envelope conformation. In the crystal structure, weak inter­molecular C—H(...)O and C—H(...)N hydrogen bonds link the mol­ecules, in which they may be effective in the stabilization of the structure.

Related literature

For general background, see: Tufariello (1984 [triangle]); Villamena & Zweier (2004 [triangle]); Halliwell (2001a [triangle],b [triangle]); Zweier & Talukder (2006 [triangle]); Janzen (1971 [triangle], 1980 [triangle]); Janzen & Haire (1990 [triangle]); Villamena et al. (2007 [triangle]); Floyd & Hensley (2000 [triangle]); Inanami & Kuwabara (1995 [triangle]); Becker et al. (2002 [triangle]). For bond-length data, see: Allen et al. (1987 [triangle]). For the preparation of N-Methyl-C-(-4-methylphenyl) nitrone, used in the synthesis, see: Heaney et al. (2001 [triangle]). For 1,3-dipolar cycloaddition of nitrones and alkenes, see: Confalone & Huie (1988 [triangle]); Torssell (1988 [triangle]); Frederickson (1997 [triangle]); Gothelf & Jorgensen (1998 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-0o806-scheme1.jpg

Experimental

Crystal data

  • C15H19NO5
  • M r = 293.31
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-65-0o806-efi1.jpg
  • a = 15.3832 (7) Å
  • b = 19.7959 (8) Å
  • c = 9.9612 (3) Å
  • V = 3033.4 (2) Å3
  • Z = 8
  • Mo Kα radiation
  • μ = 0.10 mm−1
  • T = 296 K
  • 0.78 × 0.45 × 0.27 mm

Data collection

  • Stoe IPDS-2 diffractometer
  • Absorption correction: integration (X-RED32; Stoe & Cie, 2002 [triangle]) T min = 0.973, T max = 0.989
  • 11187 measured reflections
  • 1672 independent reflections
  • 1554 reflections with I > 2σ(I)
  • R int = 0.026

Refinement

  • R[F 2 > 2σ(F 2)] = 0.027
  • wR(F 2) = 0.074
  • S = 1.07
  • 1672 reflections
  • 192 parameters
  • 1 restraint
  • H-atom parameters constrained
  • Δρmax = 0.11 e Å−3
  • Δρmin = −0.10 e Å−3

Data collection: X-AREA (Stoe & Cie, 2002 [triangle]); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002 [triangle]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809009350/hk2635sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809009350/hk2635Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors acknowledge the Faculty of Arts and Sciences, Ondokuz Mayıs University, Turkey, for the use of the Stoe IPDS-2 diffractometer (purchased under grant No. F.279 of the University Research Fund).

supplementary crystallographic information

Comment

Nitrones are members of a class of compounds which are commonly used as precursors in the syntheses of natural products (Tufariello, 1984), as spin-trapping reagents in the identification of transient radicals (Villamena & Zweier, 2004), and as therapeutic agents (Floyd & Hensley, 2000; Inanami & Kuwabara, 1995) such as in the case of disodium-[(tert-butylimino) -methyl]benzene-1,3-disulfonate N-oxide (NXY-059) which is in clinical trials in the USA for the treatment of neurodegenerative disease (Becker et al., 2002). In recent years, it has become clear that reactive oxygen species (ROS) (e.g., radicals: O2.-, HO., HO2., RO2., RO., CO3.-, and CO2.-; and non-radicals such as H2O2, HOCl, O3, 1O2, and ROOH) are critical mediators in cardiovascular dysfunction, neurodegenerative diseases, oncogenesis, lung damage and aging, to name a few (Halliwell, 2001a; 2001b; Zweier & Talukder, 2006). Electron paramagnetic resonance (EPR) spectroscopy has been an indispensable tool for the detection of these ROS via spin trapping [Villamena & Zweier, 2004; Janzen, 1971; Janzen,1980; Janzen & Haire, 1990; Villamena et al., 2007). The nitrone-based spin traps, 5,5-dimethyl-1-pyrroline N-oxide (DMPO), 5-diethoxyphosphoryl-5- methyl-pyrroline N-oxide (DEPMPO) and 5-ethoxycarbonyl-5-methyl-pyrroline N-oxide (EMPO), are the most commonly used spin-trapping reagents and have contributed significantly to the understanding of important free radical- mediated processes in chemical, biochemical, and biological systems in spite of their many limitations. The 1,3-dipolar cycloaddition of nitrones and alkenes is a powerful synthetic device that allows up to three new stereogenic centers to be assembled in a stereospecific manner in a single step (Confalone & Huie, 1988; Torssell, 1988; Frederickson, 1997; Gothelf & Jorgensen, 1998). The syntheses of isoxazolidine derivatives is an important subject in organic chemistry because they are found in the structure of most natural compounds and drugs. In recent years, isoxazolidine derivatives have been synthesized in high yield via intermolecular cycloaddition of N-methylnitrone with disubstituted olefins and are employed for biological evaluation. In view of the importance of the isoxazolidines, we report herein the crystal structure of the title compound.

In the molecule of the title compound (Fig. 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. Ring A (C1-C6) is, of course, planar, while ring B (O1/N1/C8-C10) adopts envelope conformation with N1 atom displaced by 0.676 (3) Å from the plane of the other ring atoms.

In the crystal structure, weak intermolecular C-H···O and C-H···N hydrogen bonds (Table 1) link the molecules, in which they may be effective in the stabilization of the structure.

Experimental

N-Methyl-C-(-4-methylphenyl) nitrone, was prepared from 4-methyl benzaldehyde, N-methyl-hydroxylamine hydrochloride and sodium carbonate in CH2Cl2 according to the literature method (Heaney et al., 2001). For the preparation of the title compound, N-methyl-C-(-4-methylphenyl) nitrone (453 mg, 3 mmol) and dimethylmaleate (475 mg, 3,3 mmol) were dissolved in benzene (50 ml). The reaction mixture was refluxed for 9 h, and monitored by TLC. After evaporation of the solvent, the reaction mixture was separated by column chromatography, using the mixture of hexane/ethyl acetate (1:1) as the eluant. The cis-isomer, was recrystallized from CHCl3/hexane (1:3) in 2 d (m.p. 371-372 K).

Refinement

H atoms were positioned geometrically, with C-H = 0.93, 0.98 and 0.96 Å for aromatic, methine and methyl H, respectively, and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C), where x = 1.5 for methyl H and x = 1.2 for all other H atoms. The absolute structure could not be determined reliably, and 1474 Friedel pairs were averaged before the last cycle of refinement.

Figures

Fig. 1.
The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.

Crystal data

C15H19NO5F(000) = 1248
Mr = 293.31Dx = 1.285 Mg m3
Orthorhombic, Ccc2Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C 2 -2cCell parameters from 11187 reflections
a = 15.3832 (7) Åθ = 1.7–28.0°
b = 19.7959 (8) ŵ = 0.10 mm1
c = 9.9612 (3) ÅT = 296 K
V = 3033.4 (2) Å3Prism, colorless
Z = 80.78 × 0.45 × 0.27 mm

Data collection

Stoe IPDS-2 diffractometer1672 independent reflections
Radiation source: sealed X-ray tube1554 reflections with I > 2σ(I)
plane graphiteRint = 0.026
Detector resolution: 6.67 pixels mm-1θmax = 26.5°, θmin = 1.7°
ω scan rotation methodh = −18→19
Absorption correction: integration (X-RED32; Stoe & Cie, 2002)k = −24→24
Tmin = 0.973, Tmax = 0.989l = −12→12
11187 measured reflections

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.027H-atom parameters constrained
wR(F2) = 0.074w = 1/[σ2(Fo2) + (0.0483P)2 + 0.1649P] where P = (Fo2 + 2Fc2)/3
S = 1.07(Δ/σ)max = 0.001
1672 reflectionsΔρmax = 0.11 e Å3
192 parametersΔρmin = −0.10 e Å3
1 restraintExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0024 (3)

Special details

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)

xyzUiso*/Ueq
O10.43759 (8)0.40270 (6)0.68227 (16)0.0583 (4)
O20.61162 (9)0.28606 (7)0.63405 (15)0.0577 (3)
O30.60989 (9)0.22965 (7)0.82785 (15)0.0585 (3)
O40.66458 (9)0.42093 (7)0.75011 (16)0.0626 (4)
O50.58517 (8)0.43642 (7)0.56403 (14)0.0578 (3)
N10.41179 (9)0.33370 (7)0.64475 (16)0.0485 (3)
C10.41288 (11)0.22248 (9)0.75835 (19)0.0465 (4)
C20.43264 (13)0.18797 (10)0.6418 (2)0.0555 (4)
H20.45300.21140.56720.067*
C30.42216 (14)0.11819 (11)0.6357 (3)0.0647 (5)
H30.43520.09580.55610.078*
C40.39317 (13)0.08153 (10)0.7437 (3)0.0650 (6)
C50.37474 (15)0.11654 (12)0.8606 (3)0.0680 (6)
H50.35610.09280.93580.082*
C60.38338 (14)0.18582 (11)0.8680 (2)0.0598 (5)
H60.36930.20810.94720.072*
C70.37937 (18)0.00580 (14)0.7372 (5)0.0968 (10)
H7A0.3207−0.00460.76260.145*
H7B0.4189−0.01620.79750.145*
H7C0.3897−0.00970.64720.145*
C80.42456 (11)0.29783 (9)0.77189 (18)0.0460 (4)
H80.38250.31490.83760.055*
C90.51660 (11)0.32237 (8)0.81227 (17)0.0459 (4)
H90.52350.32150.91010.055*
C100.51412 (11)0.39570 (8)0.76058 (19)0.0494 (4)
H100.50710.42490.83930.059*
C110.32106 (12)0.33992 (12)0.6060 (3)0.0650 (5)
H11A0.31710.36380.52230.097*
H11B0.29000.36440.67400.097*
H11C0.29620.29570.59600.097*
C120.58471 (11)0.27910 (8)0.74591 (19)0.0461 (4)
C130.66586 (15)0.17845 (11)0.7714 (3)0.0746 (6)
H13A0.67990.14580.83920.112*
H13B0.71830.19910.73920.112*
H13C0.63660.15650.69840.112*
C140.59637 (11)0.41814 (8)0.6902 (2)0.0475 (4)
C150.66179 (16)0.46013 (14)0.4967 (3)0.0802 (7)
H15A0.64750.47230.40600.120*
H15B0.70490.42500.49600.120*
H15C0.68430.49890.54290.120*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0479 (6)0.0423 (6)0.0848 (10)0.0013 (5)−0.0049 (6)0.0057 (7)
O20.0693 (8)0.0515 (7)0.0524 (7)0.0065 (6)0.0100 (7)−0.0007 (6)
O30.0641 (8)0.0521 (7)0.0592 (8)0.0095 (6)−0.0029 (7)0.0078 (6)
O40.0535 (7)0.0669 (8)0.0674 (8)−0.0085 (6)−0.0091 (6)−0.0009 (7)
O50.0556 (7)0.0574 (8)0.0606 (8)−0.0062 (6)−0.0025 (6)0.0096 (6)
N10.0461 (7)0.0452 (7)0.0541 (9)−0.0016 (5)−0.0002 (6)0.0047 (7)
C10.0465 (8)0.0466 (8)0.0465 (9)−0.0038 (6)−0.0023 (7)0.0022 (8)
C20.0653 (11)0.0513 (9)0.0500 (9)−0.0020 (8)0.0027 (9)−0.0002 (9)
C30.0672 (11)0.0546 (11)0.0724 (13)−0.0016 (9)−0.0039 (11)−0.0135 (11)
C40.0526 (10)0.0491 (10)0.0935 (16)−0.0068 (7)−0.0156 (10)0.0032 (11)
C50.0703 (13)0.0613 (12)0.0725 (13)−0.0159 (10)−0.0026 (11)0.0182 (11)
C60.0674 (12)0.0619 (11)0.0500 (9)−0.0133 (9)0.0033 (9)0.0035 (9)
C70.0854 (15)0.0517 (11)0.153 (3)−0.0127 (11)−0.0152 (19)−0.0036 (16)
C80.0474 (8)0.0463 (9)0.0442 (8)−0.0017 (6)0.0061 (7)−0.0014 (7)
C90.0532 (9)0.0448 (8)0.0398 (8)−0.0009 (7)0.0006 (7)−0.0031 (7)
C100.0517 (9)0.0423 (8)0.0541 (9)0.0011 (6)0.0027 (8)−0.0073 (8)
C110.0483 (9)0.0661 (12)0.0806 (14)−0.0008 (8)−0.0074 (10)0.0108 (10)
C120.0479 (8)0.0416 (8)0.0489 (9)−0.0023 (6)−0.0026 (8)−0.0011 (8)
C130.0717 (13)0.0527 (11)0.0995 (18)0.0172 (9)−0.0032 (13)0.0027 (12)
C140.0491 (9)0.0384 (7)0.0549 (9)−0.0022 (6)−0.0027 (8)−0.0046 (8)
C150.0757 (14)0.0924 (16)0.0726 (15)−0.0240 (12)0.0079 (12)0.0166 (14)

Geometric parameters (Å, °)

C1—C21.381 (3)C10—O11.419 (2)
C1—C61.387 (3)C10—C141.513 (3)
C1—C81.508 (2)C10—H100.9800
C2—C31.392 (3)C11—N11.453 (2)
C2—H20.9300C11—H11A0.9600
C3—C41.373 (4)C11—H11B0.9600
C3—H30.9300C11—H11C0.9600
C4—C51.384 (4)C12—O21.197 (2)
C4—C71.515 (3)C12—O31.332 (2)
C5—C61.380 (3)C13—O31.444 (3)
C5—H50.9300C13—H13A0.9600
C6—H60.9300C13—H13B0.9600
C7—H7A0.9600C13—H13C0.9600
C7—H7B0.9600C14—O41.209 (2)
C7—H7C0.9600C14—O51.319 (2)
C8—N11.465 (2)C15—O51.435 (3)
C8—C91.550 (2)C15—H15A0.9600
C8—H80.9800C15—H15B0.9600
C9—C121.506 (2)C15—H15C0.9600
C9—C101.541 (2)N1—O11.4707 (19)
C9—H90.9800
C2—C1—C6118.35 (17)O1—C10—C14114.22 (15)
C2—C1—C8122.56 (16)O1—C10—C9107.23 (13)
C6—C1—C8119.07 (17)C14—C10—C9114.25 (13)
C1—C2—C3120.1 (2)O1—C10—H10106.9
C1—C2—H2119.9C14—C10—H10106.9
C3—C2—H2119.9C9—C10—H10106.9
C4—C3—C2121.9 (2)N1—C11—H11A109.5
C4—C3—H3119.1N1—C11—H11B109.5
C2—C3—H3119.1H11A—C11—H11B109.5
C3—C4—C5117.47 (18)N1—C11—H11C109.5
C3—C4—C7122.3 (3)H11A—C11—H11C109.5
C5—C4—C7120.2 (3)H11B—C11—H11C109.5
C6—C5—C4121.5 (2)O2—C12—O3123.68 (17)
C6—C5—H5119.2O2—C12—C9125.72 (17)
C4—C5—H5119.2O3—C12—C9110.57 (16)
C5—C6—C1120.6 (2)O3—C13—H13A109.5
C5—C6—H6119.7O3—C13—H13B109.5
C1—C6—H6119.7H13A—C13—H13B109.5
C4—C7—H7A109.5O3—C13—H13C109.5
C4—C7—H7B109.5H13A—C13—H13C109.5
H7A—C7—H7B109.5H13B—C13—H13C109.5
C4—C7—H7C109.5O4—C14—O5124.86 (18)
H7A—C7—H7C109.5O4—C14—C10120.68 (18)
H7B—C7—H7C109.5O5—C14—C10114.39 (15)
N1—C8—C1112.71 (14)O5—C15—H15A109.5
N1—C8—C9101.23 (13)O5—C15—H15B109.5
C1—C8—C9116.23 (14)H15A—C15—H15B109.5
N1—C8—H8108.8O5—C15—H15C109.5
C1—C8—H8108.8H15A—C15—H15C109.5
C9—C8—H8108.8H15B—C15—H15C109.5
C12—C9—C10113.98 (14)C11—N1—C8113.54 (15)
C12—C9—C8110.07 (13)C11—N1—O1104.36 (14)
C10—C9—C8100.72 (13)C8—N1—O1101.21 (13)
C12—C9—H9110.6C10—O1—N1105.84 (11)
C10—C9—H9110.6C12—O3—C13116.79 (18)
C8—C9—H9110.6C14—O5—C15115.34 (17)
C6—C1—C2—C30.5 (3)C8—C9—C10—C14−137.37 (16)
C8—C1—C2—C3178.76 (17)C10—C9—C12—O2−29.1 (3)
C1—C2—C3—C4−0.7 (3)C8—C9—C12—O283.2 (2)
C2—C3—C4—C5−0.2 (3)C10—C9—C12—O3152.90 (14)
C2—C3—C4—C7178.4 (2)C8—C9—C12—O3−94.81 (17)
C3—C4—C5—C61.3 (3)O1—C10—C14—O4172.80 (15)
C7—C4—C5—C6−177.4 (2)C9—C10—C14—O4−63.2 (2)
C4—C5—C6—C1−1.4 (3)O1—C10—C14—O5−4.3 (2)
C2—C1—C6—C50.5 (3)C9—C10—C14—O5119.63 (16)
C8—C1—C6—C5−177.80 (18)C1—C8—N1—C1175.72 (19)
C2—C1—C8—N131.2 (2)C9—C8—N1—C11−159.42 (16)
C6—C1—C8—N1−150.60 (17)C1—C8—N1—O1−173.05 (13)
C2—C1—C8—C9−85.0 (2)C9—C8—N1—O1−48.19 (14)
C6—C1—C8—C993.2 (2)C14—C10—O1—N1107.82 (15)
N1—C8—C9—C12−85.19 (15)C9—C10—O1—N1−19.84 (17)
C1—C8—C9—C1237.3 (2)C11—N1—O1—C10161.41 (16)
N1—C8—C9—C1035.45 (15)C8—N1—O1—C1043.31 (16)
C1—C8—C9—C10157.90 (15)O2—C12—O3—C13−6.6 (3)
C12—C9—C10—O1108.09 (17)C9—C12—O3—C13171.52 (16)
C8—C9—C10—O1−9.72 (16)O4—C14—O5—C150.9 (3)
C12—C9—C10—C14−19.6 (2)C10—C14—O5—C15177.92 (18)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C2—H2···O3i0.932.603.300 (2)133
C6—H6···O2ii0.932.443.312 (3)157
C9—H9···N1ii0.982.553.497 (2)162
C10—H10···O5ii0.982.663.481 (2)142
C15—H15a···O4iii0.962.643.403 (3)137

Symmetry codes: (i) −x+1, y, z−1/2; (ii) −x+1, y, z+1/2; (iii) x, −y+1, z−1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HK2635).

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