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

Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 67| Part 5| May 2011| Page o1245

Racemic methyl 3,10-dioxa-2-aza­tri­cyclo­[6.2.1.02,6]undecane-4-carboxyl­ate

aControlled Release and Delivery Laboratory, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia, bCenter of Research Excellence in Petroleum Refining, and Petrochemicals Research Institute, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia, and cDepartment of Chemistry, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
*Correspondence e-mail: fettouhi@kfupm.edu.sa

(Received 13 April 2011; accepted 20 April 2011; online 29 April 2011)

The structure of the racemic title compound, C10H15NO4, consists of a tricyclic skeleton comprising a six-membered piperidine ring and five-membered isoxazolidine and tetra­hydro­furan rings. The piperidine ring adopts a distorted chair conformation, while the isoxazolidine and tetra­hydro­furan rings have envelope conformations.

Related literature

For related piperidine geometry, see: Parkin et al. (2004[Parkin, A., Oswald, I. D. H. & Parsons, S. (2004). Acta Cryst. B60, 219-227.]). For bicyclic polyhydro­isoxazolopyridines, see: Banerji et al. (2006[Banerji, A., Bandyopadhyay, D., Sengupta, P., Basak, B., Prange, T. & Neuman, A. (2006). Tetrahedron Lett. 47, 3827-3830.]); Carmona et al. (2009[Carmona, D., Lamata, M. P., Viguri, F., Rodriguez, R., Lahoz, F. J., Fabra, M. J. & Oro, L. A. (2009). Tetrahedron Asymmetry, 20, 1197-1205.]). For literature related to cyclo­addition reactions of cyclic nitro­nes, see: Ali & Wazeer (1988[Ali, S. A. & Wazeer, M. I. M. (1988). J. Chem. Soc. Perkin Trans. 1, pp. 597-605.]); Ali et al. (1988[Ali, S. A., Khan, J. H. & Wazeer, M. I. M. (1988). Tetrahedron, 44, 5911-5920.]); Merino (2004[Merino, P. (2004). Science of Synthesis, Vol. 27, Heteroatom Analogues of Aldehydes and Ketones, edited by A. Padwa, pp. 511-580. Stuttgart: Thieme.]); Chandrasekhar (2005[Chandrasekhar, S. (2005). Arkivoc, xiii, 37-66.]); Moosa & Ali (2009[Moosa, B. A. & Ali, S. A. (2009). Tetrahedron, 65, 8231-8243.], 2010[Moosa, B. A. & Ali, S. A. (2010). Arkivoc, x, 132-148.]). For the natural product SB-219383 and its inhibitory activity against tyrosyl tRNA sythetase, see: Houge-Frydrych et al. (2000[Houge-Frydrych, C. S. V., Readshaw, S. A. & Bell, D. J. (2000). J. Antibiot. 53, 351-356.]); Stefanska et al. (2000[Stefanska, A. L., Coates, N. J., Mensah, L. M., Pope, A. J., Ready, S. J. & Warr, S. R. (2000). J. Antibiot. 53, 345-350.]).

[Scheme 1]

Experimental

Crystal data
  • C10H15NO4

  • Mr = 213.23

  • Monoclinic, P 21 /c

  • a = 11.213 (3) Å

  • b = 7.1075 (18) Å

  • c = 12.910 (3) Å

  • β = 91.546 (5)°

  • V = 1028.4 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 294 K

  • 0.20 × 0.10 × 0.05 mm

Data collection
  • Bruker SMART APEX area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.979, Tmax = 0.995

  • 13498 measured reflections

  • 2563 independent reflections

  • 1567 reflections with I > 2σ(I)

  • Rint = 0.052

Refinement
  • R[F2 > 2σ(F2)] = 0.057

  • wR(F2) = 0.155

  • S = 1.03

  • 2563 reflections

  • 185 parameters

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

  • Δρmax = 0.24 e Å−3

  • Δρmin = −0.22 e Å−3

Data collection: SMART (Bruker, 2008[Bruker, (2008). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker, (2008). SMART and SAINT. 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, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

1,3-Dipolar cycloaddition reaction of cyclic nitrones with alkenes shows greater stereoselectivity and reactivity compared to their acyclic counterparts for applications in the synthesis of natural products (Merino, 2004; Moosa & Ali, 2009, 2010; Ali et al., 1988; Ali & Wazeer, 1988). Our interest in developing a synthetic methodology to construct the ring skeleton present in a natural product called SB-219383 (Houge-Frydrych et al., 2000), first member of a new class of compounds having inhibitory activity against tyrosyl tRNA sythetase (Stefanska et al., 2000), led to explore the synthesis and cycloaddition of the bicyclic nitrone 1-oxa-5,6-dehydro-6-aza-bicyclo[3,2,1]heptane 6-oxide with methyl acrylate. The structure of a recemic sample of the cycloadduct is reported here. It consists of a tricyclic skeleton corresponding to a cis-invertomer with the nitrogen lone pair in axial position. The two C—N bond lengths of the piperidine ring are N1—C9: 1.453 (2) Å and N1—C5: 1.473 (2) Å. The former bond is shorter presumably as a result of anomeric effect (Chandrasekhar, 2005), inducing a partial double bond character. The bond distances are consistent with those reported for piperidine (Parkin et al., 2004) and bicyclic polyhydroisoxazolopyridines (Banerji et al., 2006; Carmona et al., 2009). The piperidine ring adopts a distorted chair conformation likely due to the strain of the 5-membered rings. Angular constraints imposed by the five-membered tetrahydrofuran ring skeleton led to the squeezing of the C7—C8—C9 angle to 97.8 (2)°; the corresponding bond angle in piperidine, the parent six-membered heterocyclic, is 110.21 (7)°. The angles C5—N1—C9, N1—C5—C6 and C5—C6—C7 on the other end of the six-membered ring were expanded to 114.1 (2)°, 112.3 (2)° and 113.7 (2)°, respectively, while the corresponding angles in piperidine are 111.04 (7)°, 109.84 (7)° and 110.70 (7)° (Parkin et al., 2004). The destabilizing diaxial interactions among the three axially oriented substituents in the piperidine ring is somewhat relieved by moving outward from their ideal axial positions. This leads to a flattening of the chair at N1, C5 and C6. The isoxazolidine ring adopts an envelope conformation with N1, O3, C3 and C4 essentially in the plane while C5 is 0.482 (3) Å out of the plane. The dihedral angle between the previous plane and the plane N1—C5—C4 is 31.9 (2)°. The tetrahydrofuran ring has also an envelope conformation with C8 at 0.733 (3) Å out of the plane C9—O4—C10—C7 which has a dihedral angle of 47.0 (2)° with the plane C7—C8—C9.

Related literature top

For related piperidine geometry, see: Parkin et al. (2004). For bicyclic polyhydroisoxazolopyridines, see: Banerji et al. (2006); Carmona et al. (2009). For literature related to cycloaddition reactions of cyclic nitrones, see: Ali & Wazeer (1988); Ali et al. (1988); Merino (2004); Chandrasekhar (2005); Moosa & Ali (2009, 2010). For the relevent natural product SB-219383 and its inhibitory activity against tyrosyl tRNA sythetase, see: Houge-Frydrych et al. (2000); Stefanska et al. (2000).

Experimental top

To a stirred solution of N-hydroxy-4-piperidinemethanol (0.39 g, 3.0 mmol) in chloroform (20 ml) was added mercuric oxide (0.65 g, 12 mmol) and anhydrous magnesium sulfate (150 mg) in 10 min. The reaction mixture was then stirred at room temperature for 6 h. The mixture was filtered over a bed of magnesium sulfate to obtain a solution of the bicyclic nitrone 1-oxa-5,6-dehydro-6-aza-bicyclo[3,2,1]heptane 6-oxide which was used without isolation. The solution of the nitrone and methyl acrylate (2 ml) was stirred at room temperature for 4 h. After removal of the solvent and excess methyl acrylate, the reaction mixture was concentrated and the residual liquid was chromatographed over silica using 9:1 ether/methanol mixture as an eluant to give the cycloadduct as a solid (0.28 g, 44%). Colorless blocks were obtained after crystallization at 0°C from ether/CH2Cl2 (9/1) mixture.

Refinement top

Methyl H atoms were included as a rigid group and refined using a riding model with C—H = 0.96 Å and Uiso(H) = 1.5Ueq(C). All other H atoms were located in a difference Fourier map and refined isotropically.

Computing details top

Data collection: SMART (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, 1997); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure with atom labels and 30% probability displacement ellipsoids for non-H atoms.
methyl 3,10-dioxa-2-azatricyclo[6.2.1.02,6]undecane-4-carboxylate top
Crystal data top
C10H15NO4F(000) = 456
Mr = 213.23Dx = 1.377 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 13498 reflections
a = 11.213 (3) Åθ = 1.8–28.4°
b = 7.1075 (18) ŵ = 0.11 mm1
c = 12.910 (3) ÅT = 294 K
β = 91.546 (5)°Block, colourless
V = 1028.4 (4) Å30.20 × 0.10 × 0.05 mm
Z = 4
Data collection top
Bruker SMART APEX area-detector
diffractometer
2563 independent reflections
Radiation source: normal-focus sealed tube1567 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.052
ω scansθmax = 28.4°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1414
Tmin = 0.979, Tmax = 0.995k = 99
13498 measured reflectionsl = 1717
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)] = 0.057Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.155H atoms treated by a mixture of independent and constrained refinement
S = 1.03 w = 1/[σ2(Fo2) + (0.0701P)2 + 0.2128P]
where P = (Fo2 + 2Fc2)/3
2563 reflections(Δ/σ)max = 0.002
185 parametersΔρmax = 0.24 e Å3
0 restraintsΔρmin = 0.22 e Å3
Crystal data top
C10H15NO4V = 1028.4 (4) Å3
Mr = 213.23Z = 4
Monoclinic, P21/cMo Kα radiation
a = 11.213 (3) ŵ = 0.11 mm1
b = 7.1075 (18) ÅT = 294 K
c = 12.910 (3) Å0.20 × 0.10 × 0.05 mm
β = 91.546 (5)°
Data collection top
Bruker SMART APEX area-detector
diffractometer
2563 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1567 reflections with I > 2σ(I)
Tmin = 0.979, Tmax = 0.995Rint = 0.052
13498 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0570 restraints
wR(F2) = 0.155H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.24 e Å3
2563 reflectionsΔρmin = 0.22 e Å3
185 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
N10.14231 (14)0.9997 (2)0.39231 (12)0.0433 (4)
O10.43183 (15)0.7626 (3)0.60910 (14)0.0821 (6)
O20.24093 (17)0.6880 (3)0.59172 (15)0.0838 (6)
O30.23751 (14)0.86158 (19)0.40074 (11)0.0559 (4)
O40.26276 (13)1.22561 (19)0.29897 (11)0.0516 (4)
C10.4428 (3)0.6375 (5)0.6972 (2)0.0950 (11)
H1A0.38340.66870.74650.142*
H1B0.52070.65070.72900.142*
H1C0.43160.50990.67450.142*
C20.3263 (2)0.7726 (3)0.56322 (17)0.0514 (5)
C30.3243 (2)0.9186 (3)0.47749 (16)0.0484 (5)
C40.2854 (2)1.1087 (3)0.51816 (18)0.0508 (5)
C50.15285 (19)1.1108 (3)0.48841 (15)0.0458 (5)
C60.0935 (2)1.3043 (3)0.47755 (17)0.0515 (5)
C70.1024 (2)1.3900 (3)0.36965 (17)0.0535 (6)
C80.0548 (2)1.2468 (3)0.29092 (19)0.0542 (6)
C90.15798 (18)1.1088 (3)0.29848 (15)0.0441 (5)
C100.2287 (2)1.4113 (3)0.3337 (2)0.0565 (6)
H40.400 (2)0.929 (3)0.4479 (16)0.056 (6)*
H50.3284 (19)1.202 (3)0.4850 (17)0.050 (6)*
H60.301 (2)1.116 (3)0.590 (2)0.069 (7)*
H70.1119 (18)1.042 (3)0.5399 (16)0.049 (6)*
H80.011 (2)1.290 (3)0.4920 (18)0.053 (6)*
H90.1310 (19)1.383 (3)0.5271 (17)0.051 (6)*
H100.061 (2)1.508 (4)0.3653 (17)0.061 (6)*
H110.020 (2)1.189 (3)0.3108 (17)0.060 (7)*
H120.050 (2)1.304 (4)0.220 (2)0.073 (7)*
H130.1645 (16)1.018 (3)0.2423 (15)0.041 (5)*
H140.235 (2)1.501 (4)0.2774 (19)0.072 (7)*
H150.284 (2)1.451 (3)0.3903 (18)0.056 (6)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0489 (10)0.0403 (9)0.0410 (9)0.0017 (7)0.0035 (7)0.0061 (7)
O10.0499 (10)0.1099 (15)0.0864 (13)0.0060 (9)0.0012 (9)0.0487 (11)
O20.0686 (12)0.0947 (14)0.0873 (13)0.0279 (11)0.0100 (10)0.0354 (11)
O30.0732 (11)0.0427 (8)0.0513 (9)0.0081 (7)0.0086 (7)0.0092 (7)
O40.0545 (9)0.0480 (8)0.0532 (9)0.0020 (7)0.0173 (7)0.0050 (7)
C10.0693 (18)0.124 (3)0.091 (2)0.0066 (17)0.0051 (15)0.058 (2)
C20.0501 (13)0.0510 (12)0.0534 (13)0.0031 (10)0.0046 (10)0.0037 (10)
C30.0473 (12)0.0519 (12)0.0462 (12)0.0021 (10)0.0027 (9)0.0016 (9)
C40.0619 (14)0.0484 (12)0.0420 (12)0.0078 (11)0.0028 (10)0.0022 (10)
C50.0555 (13)0.0459 (11)0.0363 (10)0.0072 (9)0.0093 (9)0.0032 (9)
C60.0563 (14)0.0519 (12)0.0470 (12)0.0013 (11)0.0122 (10)0.0102 (10)
C70.0668 (15)0.0436 (11)0.0505 (12)0.0114 (11)0.0099 (10)0.0018 (10)
C80.0569 (14)0.0598 (14)0.0460 (13)0.0079 (11)0.0021 (11)0.0017 (10)
C90.0495 (12)0.0448 (11)0.0382 (11)0.0015 (9)0.0059 (9)0.0069 (9)
C100.0726 (16)0.0437 (12)0.0539 (14)0.0049 (11)0.0158 (12)0.0010 (10)
Geometric parameters (Å, º) top
N1—O31.452 (2)C4—H50.93 (2)
N1—C91.453 (2)C4—H60.94 (3)
N1—C51.473 (2)C5—C61.532 (3)
O1—C21.311 (3)C5—H70.95 (2)
O1—C11.446 (3)C6—C71.526 (3)
O2—C21.197 (3)C6—H80.95 (2)
O3—C31.429 (3)C6—H90.94 (2)
O4—C91.439 (2)C7—C101.509 (3)
O4—C101.449 (3)C7—C81.525 (3)
C1—H1A0.9600C7—H100.96 (2)
C1—H1B0.9600C8—C91.518 (3)
C1—H1C0.9600C8—H110.98 (2)
C2—C31.517 (3)C8—H121.01 (3)
C3—C41.518 (3)C9—H130.976 (19)
C3—H40.95 (2)C10—H140.97 (3)
C4—C51.525 (3)C10—H150.99 (2)
O3—N1—C9108.55 (14)C6—C5—H7107.9 (12)
O3—N1—C5104.91 (14)C7—C6—C5113.74 (17)
C9—N1—C5114.04 (16)C7—C6—H8107.9 (14)
C2—O1—C1116.43 (19)C5—C6—H8108.0 (13)
C3—O3—N1110.24 (14)C7—C6—H9110.1 (13)
C9—O4—C10107.76 (15)C5—C6—H9106.8 (13)
O1—C1—H1A109.5H8—C6—H9110.3 (19)
O1—C1—H1B109.5C10—C7—C8100.20 (18)
H1A—C1—H1B109.5C10—C7—C6113.9 (2)
O1—C1—H1C109.5C8—C7—C6108.17 (19)
H1A—C1—H1C109.5C10—C7—H10110.8 (13)
H1B—C1—H1C109.5C8—C7—H10112.4 (14)
O2—C2—O1123.6 (2)C6—C7—H10110.9 (13)
O2—C2—C3124.9 (2)C9—C8—C797.78 (18)
O1—C2—C3111.22 (19)C9—C8—H11111.8 (14)
O3—C3—C2107.94 (18)C7—C8—H11113.3 (13)
O3—C3—C4107.17 (17)C9—C8—H12110.2 (14)
C2—C3—C4110.81 (18)C7—C8—H12110.5 (15)
O3—C3—H4110.3 (13)H11—C8—H12112 (2)
C2—C3—H4110.7 (13)O4—C9—N1114.92 (16)
C4—C3—H4109.9 (13)O4—C9—C8104.39 (17)
C3—C4—C5102.07 (17)N1—C9—C8106.81 (17)
C3—C4—H5108.5 (13)O4—C9—H13108.0 (11)
C5—C4—H5113.0 (13)N1—C9—H13106.1 (11)
C3—C4—H6110.0 (15)C8—C9—H13117.0 (11)
C5—C4—H6113.8 (15)O4—C10—C7105.13 (18)
H5—C4—H6109 (2)O4—C10—H14110.0 (15)
N1—C5—C4105.22 (16)C7—C10—H14112.6 (15)
N1—C5—C6112.30 (17)O4—C10—H15108.9 (13)
C4—C5—C6116.70 (19)C7—C10—H15112.1 (13)
N1—C5—H7106.4 (12)H14—C10—H15108 (2)
C4—C5—H7107.7 (13)

Experimental details

Crystal data
Chemical formulaC10H15NO4
Mr213.23
Crystal system, space groupMonoclinic, P21/c
Temperature (K)294
a, b, c (Å)11.213 (3), 7.1075 (18), 12.910 (3)
β (°) 91.546 (5)
V3)1028.4 (4)
Z4
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.20 × 0.10 × 0.05
Data collection
DiffractometerBruker SMART APEX area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.979, 0.995
No. of measured, independent and
observed [I > 2σ(I)] reflections
13498, 2563, 1567
Rint0.052
(sin θ/λ)max1)0.669
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.057, 0.155, 1.03
No. of reflections2563
No. of parameters185
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.24, 0.22

Computer programs: SMART (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

The authors acknowledge King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia, for financial support.

References

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 5| May 2011| Page o1245
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