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Acta Crystallogr Sect E Struct Rep Online. 2008 January 1; 64(Pt 1): o329.
Published online 2007 December 21. doi:  10.1107/S160053680706686X
PMCID: PMC2915371

2-(Methoxy­meth­oxy)-1-(4-oxobicyclo­[3.1.0]hexan-1-yl)ethyl 4-nitro­benzoate

Abstract

In the title compound, C17H19NO7, the cyclo­pentane ring is in an envelope conformation in which the methyl­ene group forming the flap is cis to the cyclo­propane group. The relative configuration between the 4-nitro­benzo­yloxy substituent on the side chain and the cyclo­propane ring is trans and the methoxy­lmethyl group adopts the expected conformation in which the two O atoms are gauche to one another.

Related literature

For the synthesis of mimetics of biologically important furan­oside rings, see: Callam & Lowary (2000 [triangle], 2001 [triangle]); Callam et al. (2001 [triangle]); Centrone & Lowary (2002 [triangle]). For examples of crystal structures of bicyclo­[3.1.0]hexane systems, see; Gurskaya et al. (1990 [triangle], 1996 [triangle]); Gallucci et al. (2000 [triangle]); Garcia et al. (1992 [triangle]); Guthrie et al. (1981 [triangle]); Màrton-Merész et al. (1983 [triangle]); Biswas et al. (1996 [triangle]); Bai et al. (2004 [triangle]). For related literature, see: Hamon & Shirley (1988 [triangle]); Li & Lowary (2008 [triangle]); Wolfe (1972 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-64-0o329-scheme1.jpg

Experimental

Crystal data

  • C17H19NO7
  • M r = 349.33
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-0o329-efi1.jpg
  • a = 8.3387 (5) Å
  • b = 10.1389 (6) Å
  • c = 10.4935 (6) Å
  • α = 98.5259 (8)°
  • β = 100.4967 (8)°
  • γ = 101.1562 (7)°
  • V = 840.22 (9) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.11 mm−1
  • T = 193 (2) K
  • 0.52 × 0.50 × 0.47 mm

Data collection

  • Bruker PLATFORM diffractometer SMART 1000 CCD area-detector
  • Absorption correction: multi-scan (SADABS; Sheldrick, 2003 [triangle]) T min = 0.946, T max = 0.951
  • 7436 measured reflections
  • 3825 independent reflections
  • 3476 reflections with I > 2σ(I)
  • R int = 0.009

Refinement

  • R[F 2 > 2σ(F 2)] = 0.042
  • wR(F 2) = 0.120
  • S = 1.05
  • 3825 reflections
  • 227 parameters
  • H-atom parameters constrained
  • Δρmax = 0.31 e Å−3
  • Δρmin = −0.17 e Å−3

Data collection: SMART (Bruker, 1997 [triangle]); cell refinement: SAINT (Bruker, 1997 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a [triangle]); molecular graphics: SHELXTL (Sheldrick, 1997b [triangle]); software used to prepare material for publication: SHELXTL.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053680706686X/lh2582sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053680706686X/lh2582Isup2.hkl

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

Acknowledgments

This work was supported by the Natural Science and Engineering Research Council of Canada, the Alberta Ingenuity Centre for Carbohydrate Science and the University of Alberta.

supplementary crystallographic information

Comment

In the course of our studies on the synthesis of mimetics of biologically important furanoside rings (Callam & Lowary, 2000; Callam & Lowary, 2001; Callam et al., 2001; Centrone & Lowary, 2002), we targeted compounds of the general structure (I) for synthesis. A key step in the route to these compounds (Li & Lowary, 2008) was a base-promoted ring contraction of epoxyketone (II) [see Fig. 1] (Hamon & Shirley, 1988), which gave a 1:1 mixture of two steroisomeric products (III) and (IV), both as racemic mixtures. In these products, it was critical to determine the relative configuration of the carbon bearing the OH group and the cyclopropane ring and doing so by spectroscopic methods was not possible. Therefore, derivatives of both (III) and (IV) were prepared in hopes of obtaining a crystalline material. We were pleased to discover that esterification of (IV) with 4-nitrobenzoyl chloride gave a crystalline product (V) from which the relative configuration of these two groups could be established by X-ray crystallography.

The molecular structure of (V) is shown in Fig. 2. In common with other bicyclo[3.1.0]hexane systems for which crystal structures have been reported (examples: Gurskaya et al., 1990; Gurskaya et al., 1996; Gallucci et al., 2000; Garcia et al., 1992; Guthrie et al., 1981; Màrton-Merész et al., 1983; Biswas et al., 1996; Bai et al., 2004), the five-membered ring is puckered into an envelope in which C3 is above the plane formed by C1, C2, C4 and C5. This places C3 cis to the cyclopropane moiety that is fused to the cyclopentane ring. As can clearly be seen, the relative configuration of the stereogenic centre substituted with the 4-nitrobenzoyloxy group and the cyclopropane is trans. Thus, it is possible to establish the structure of (IV) and, by inference, (III). The methoxymethoxy group present in the side chain adopted the expected conformation (Wolfe, 1972) in which the two O atoms are gauche to each other.

Experimental

1-[2'-(methoxymethoxy)-1'-4-nitrobenzoyloxyethyl]bicyclo[3.1.0]hexan-4-one (V). To a stirred solution of (IV) (1.23 g, 6.15 mmol) in CH2Cl2-pyridine (10:1, 8.8 ml) was added 4-nitrobenzoyl chloride (1.36 g, 7.38 mmol) at 273 K. The mixture was then warmed to room temperature and stirred for 1 h. The reaction mixture was quenched by adding CH3OH, and then diluted with CH2Cl2. The solution was washed with 1 M HCl and water. The organic layer was dried (Na2SO4), filtered, concentrated, and the residue was purified by chromatography (1:1 EtOAc-hexane) to provide the product (V) as a light yellow solid (yield 1.60 g, 76%). This material was recrystallized from CH2Cl2 to provide a crystalline solid (m.p. 380–382 K). Rf 0.36 (1:1 EtOAc-Hexane); 1H NMR (500 MHz, CDCl3, δH) 8.32–8.30 (m, 2 H, Ar), 8.23–8.21 (m, 2 H, Ar), 5.11 (dd, 1 H, J = 4.7, 7.0 Hz, H-7), 4.67–4.64 (m, 2 H, OCH2O), 3.95–3.88 (m, 2 H, MOMOCH2), 3.35 (s, 3 H, OCH3), 2.40–2.32 (m, 1 H, H-3), 2.16–2.13 (m, 3 H, H-2, H-3), 2.00 (dd, 1 H, J = 3.6, 9.4 Hz, H-5), 1.47 (dd, 1 H, J = 5.2, 9.4 Hz, H-6), 1.28 (dd, 1 H, J = 3.6, 5.2 Hz, H-6); 13C NMR (125 MHz, CDCl3, δC) 212.3 (C-4), 163.9 (C-11), 150.7 (Ar), 135.2 (Ar), 130.4 (Ar x 2), 123.6 (Ar x 2), 96.6 (C-9), 76.2 (C-7), 67.3 (C-8), 55.5 (C-10), 34.3 (C-1), 32.8 (C-5), 32.6 (C-3), 22.7 (C-2), 17.9 (C-6). HRMS (ESI) m/z calculated for C17H19NO7 + Na: 372.1054, found: 372.1055.

Refinement

Hydrogen atoms were generated in idealized positions (according to the sp2 or sp3 geometries of their parent carbon or oxygen atoms), and then refined using a riding model with fixed C—H distances (C—H = 0.95–1.00 Å) and with Uiso(H) = 1.2Ueq(C).

Figures

Fig. 1.
Schemes of title (IV) and related compounds.
Fig. 2.
Perspective view of (V), showing the atom labelling scheme. Non- hydrogen atoms are represented by ellipsoids at the 50% probability level. Hydrogen atoms are shown with arbitrarily small radii.

Crystal data

C17H19NO7Z = 2
Mr = 349.33F000 = 368
Triclinic, P1Dx = 1.381 Mg m3
Hall symbol: -P 1Mo Kα radiation λ = 0.71073 Å
a = 8.3387 (5) ÅCell parameters from 7818 reflections
b = 10.1389 (6) Åθ = 2.6–27.5º
c = 10.4935 (6) ŵ = 0.11 mm1
α = 98.5259 (8)ºT = 193 (2) K
β = 100.4967 (8)ºFragment, colourless
γ = 101.1562 (7)º0.52 × 0.50 × 0.47 mm
V = 840.22 (9) Å3

Data collection

Bruker PLATFORM diffractometer/SMART 1000 CCD area-detector3825 independent reflections
Radiation source: fine-focus sealed tube3476 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.009
Detector resolution: 8.192 pixels mm-1θmax = 27.5º
T = 193(2) Kθmin = 2.0º
ω scansh = −10→10
Absorption correction: multi-scan(SADABS; Sheldrick, 2003)k = −13→13
Tmin = 0.946, Tmax = 0.951l = −13→13
7436 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)] = 0.042H-atom parameters constrained
wR(F2) = 0.120  w = 1/[σ2(Fo2) + (0.0703P)2 + 0.1568P] where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max = 0.013
3825 reflectionsΔρmax = 0.31 e Å3
227 parametersΔρmin = −0.17 e Å3
Primary atom site location: structure-invariant direct methodsExtinction correction: none

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
O10.09546 (12)0.07242 (11)0.73892 (11)0.0553 (3)
O20.27720 (9)0.22849 (8)0.35099 (8)0.03307 (19)
O30.36653 (10)0.48159 (9)0.28812 (8)0.0367 (2)
O40.19060 (11)0.53166 (10)0.10951 (9)0.0469 (2)
O50.54644 (13)0.22855 (12)0.42875 (11)0.0650 (3)
O60.43439 (13)−0.32377 (10)−0.08313 (10)0.0534 (3)
O70.18678 (14)−0.29604 (11)−0.15763 (10)0.0602 (3)
N0.32018 (14)−0.26560 (10)−0.07714 (10)0.0398 (2)
C10.16536 (13)0.31828 (10)0.53155 (10)0.0302 (2)
C2−0.01745 (14)0.24464 (13)0.47296 (12)0.0384 (3)
H2A−0.02670.17880.39080.046*
H2B−0.08640.31120.45270.046*
C3−0.07499 (15)0.16936 (15)0.57953 (14)0.0458 (3)
H3A−0.13920.22200.62980.055*
H3B−0.14660.07750.53890.055*
C40.08438 (15)0.15744 (12)0.66935 (12)0.0391 (3)
C50.22604 (14)0.26104 (11)0.65309 (11)0.0344 (2)
H50.34210.24530.67170.041*
C60.19962 (16)0.40686 (12)0.66433 (11)0.0379 (3)
H6A0.10240.42640.69940.046*
H6B0.30030.48310.68900.046*
C70.28480 (13)0.35255 (10)0.44415 (10)0.0294 (2)
H70.40110.38730.49900.035*
C80.24071 (13)0.45645 (11)0.36257 (11)0.0331 (2)
H8A0.12910.42030.30280.040*
H8B0.23840.54220.42060.040*
C90.34064 (15)0.57459 (13)0.20414 (12)0.0414 (3)
H9A0.34150.66360.25820.050*
H9B0.43480.58920.15860.050*
C100.18474 (19)0.41015 (17)0.01905 (14)0.0547 (4)
H10A0.07770.3849−0.04540.066*
H10B0.19560.33560.06740.066*
H10C0.27690.4264−0.02700.066*
C110.41618 (14)0.18250 (11)0.35071 (11)0.0332 (2)
C120.38783 (13)0.06385 (10)0.23884 (10)0.0297 (2)
C130.52157 (14)0.00427 (11)0.22180 (11)0.0328 (2)
H130.62740.03810.28110.039*
C140.50030 (14)−0.10469 (11)0.11803 (11)0.0328 (2)
H140.5905−0.14610.10510.039*
C150.34449 (14)−0.15100 (10)0.03447 (10)0.0317 (2)
C160.20974 (15)−0.09435 (12)0.04924 (12)0.0385 (3)
H160.1041−0.1290−0.01010.046*
C170.23241 (14)0.01446 (12)0.15285 (12)0.0361 (2)
H170.14160.05530.16510.043*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0480 (5)0.0566 (6)0.0701 (7)0.0130 (4)0.0196 (5)0.0295 (5)
O20.0283 (4)0.0314 (4)0.0349 (4)0.0070 (3)0.0051 (3)−0.0062 (3)
O30.0310 (4)0.0466 (5)0.0339 (4)0.0100 (3)0.0069 (3)0.0108 (3)
O40.0386 (5)0.0592 (6)0.0436 (5)0.0144 (4)0.0021 (4)0.0154 (4)
O50.0436 (5)0.0701 (7)0.0627 (6)0.0286 (5)−0.0171 (5)−0.0310 (5)
O60.0586 (6)0.0459 (5)0.0544 (6)0.0203 (4)0.0154 (5)−0.0091 (4)
O70.0642 (7)0.0551 (6)0.0463 (5)0.0174 (5)−0.0092 (5)−0.0168 (4)
N0.0500 (6)0.0325 (5)0.0347 (5)0.0094 (4)0.0092 (4)−0.0001 (4)
C10.0295 (5)0.0306 (5)0.0287 (5)0.0084 (4)0.0044 (4)0.0006 (4)
C20.0277 (5)0.0490 (6)0.0357 (6)0.0080 (5)0.0045 (4)0.0033 (5)
C30.0306 (6)0.0577 (8)0.0489 (7)0.0069 (5)0.0108 (5)0.0110 (6)
C40.0372 (6)0.0409 (6)0.0414 (6)0.0102 (5)0.0132 (5)0.0075 (5)
C50.0317 (5)0.0365 (5)0.0335 (5)0.0081 (4)0.0040 (4)0.0052 (4)
C60.0446 (6)0.0356 (6)0.0311 (5)0.0095 (5)0.0081 (5)−0.0018 (4)
C70.0277 (5)0.0277 (5)0.0292 (5)0.0063 (4)0.0042 (4)−0.0033 (4)
C80.0310 (5)0.0350 (5)0.0332 (5)0.0091 (4)0.0075 (4)0.0035 (4)
C90.0384 (6)0.0440 (6)0.0402 (6)0.0055 (5)0.0052 (5)0.0126 (5)
C100.0476 (7)0.0665 (9)0.0422 (7)0.0082 (6)−0.0013 (6)0.0063 (6)
C110.0316 (5)0.0335 (5)0.0326 (5)0.0104 (4)0.0040 (4)0.0004 (4)
C120.0307 (5)0.0282 (5)0.0294 (5)0.0071 (4)0.0065 (4)0.0028 (4)
C130.0304 (5)0.0332 (5)0.0332 (5)0.0096 (4)0.0033 (4)0.0024 (4)
C140.0354 (5)0.0314 (5)0.0345 (5)0.0128 (4)0.0099 (4)0.0057 (4)
C150.0400 (6)0.0260 (5)0.0285 (5)0.0068 (4)0.0089 (4)0.0025 (4)
C160.0314 (5)0.0375 (6)0.0395 (6)0.0054 (4)0.0012 (4)−0.0040 (5)
C170.0292 (5)0.0366 (5)0.0397 (6)0.0095 (4)0.0057 (4)−0.0018 (4)

Geometric parameters (Å, °)

O1—C41.2155 (16)C5—H51.0000
O2—C111.3306 (13)C6—H6A0.9900
O2—C71.4573 (11)C6—H6B0.9900
O3—C91.4029 (14)C7—C81.5100 (15)
O3—C81.4249 (13)C7—H71.0000
O4—C91.3962 (14)C8—H8A0.9900
O4—C101.4262 (18)C8—H8B0.9900
O5—C111.1978 (14)C9—H9A0.9900
O6—N1.2194 (14)C9—H9B0.9900
O7—N1.2222 (14)C10—H10A0.9800
N—C151.4771 (13)C10—H10B0.9800
C1—C61.4880 (14)C10—H10C0.9800
C1—C71.4991 (15)C11—C121.5005 (14)
C1—C51.5223 (15)C12—C171.3905 (15)
C1—C21.5301 (15)C12—C131.3936 (15)
C2—C31.5395 (18)C13—C141.3909 (15)
C2—H2A0.9900C13—H130.9500
C2—H2B0.9900C14—C151.3799 (15)
C3—C41.5194 (17)C14—H140.9500
C3—H3A0.9900C15—C161.3796 (16)
C3—H3B0.9900C16—C171.3870 (15)
C4—C51.4746 (16)C16—H160.9500
C5—C61.5271 (16)C17—H170.9500
C11—O2—C7118.68 (8)O2—C7—H7109.6
C9—O3—C8113.65 (9)C1—C7—H7109.6
C9—O4—C10112.74 (10)C8—C7—H7109.6
O6—N—O7124.19 (10)O3—C8—C7106.79 (8)
O6—N—C15117.96 (10)O3—C8—H8A110.4
O7—N—C15117.85 (10)C7—C8—H8A110.4
C6—C1—C7117.45 (9)O3—C8—H8B110.4
C6—C1—C560.96 (7)C7—C8—H8B110.4
C7—C1—C5118.28 (9)H8A—C8—H8B108.6
C6—C1—C2116.10 (9)O4—C9—O3113.68 (10)
C7—C1—C2120.97 (9)O4—C9—H9A108.8
C5—C1—C2108.03 (9)O3—C9—H9A108.8
C1—C2—C3105.52 (9)O4—C9—H9B108.8
C1—C2—H2A110.6O3—C9—H9B108.8
C3—C2—H2A110.6H9A—C9—H9B107.7
C1—C2—H2B110.6O4—C10—H10A109.5
C3—C2—H2B110.6O4—C10—H10B109.5
H2A—C2—H2B108.8H10A—C10—H10B109.5
C4—C3—C2105.68 (9)O4—C10—H10C109.5
C4—C3—H3A110.6H10A—C10—H10C109.5
C2—C3—H3A110.6H10B—C10—H10C109.5
C4—C3—H3B110.6O5—C11—O2125.11 (10)
C2—C3—H3B110.6O5—C11—C12124.22 (10)
H3A—C3—H3B108.7O2—C11—C12110.68 (9)
O1—C4—C5125.17 (11)C17—C12—C13120.31 (10)
O1—C4—C3125.78 (11)C17—C12—C11121.15 (9)
C5—C4—C3108.97 (10)C13—C12—C11118.53 (9)
C4—C5—C1107.41 (9)C14—C13—C12120.05 (10)
C4—C5—C6115.41 (10)C14—C13—H13120.0
C1—C5—C658.41 (7)C12—C13—H13120.0
C4—C5—H5119.9C15—C14—C13118.12 (10)
C1—C5—H5119.9C15—C14—H14120.9
C6—C5—H5119.9C13—C14—H14120.9
C1—C6—C560.63 (7)C16—C15—C14123.09 (10)
C1—C6—H6A117.7C16—C15—N118.07 (10)
C5—C6—H6A117.7C14—C15—N118.84 (10)
C1—C6—H6B117.7C15—C16—C17118.32 (10)
C5—C6—H6B117.7C15—C16—H16120.8
H6A—C6—H6B114.8C17—C16—H16120.8
O2—C7—C1108.39 (8)C16—C17—C12120.11 (10)
O2—C7—C8106.47 (8)C16—C17—H17119.9
C1—C7—C8113.09 (8)C12—C17—H17119.9
C6—C1—C2—C3−52.63 (13)C9—O3—C8—C7178.58 (9)
C7—C1—C2—C3154.16 (10)O2—C7—C8—O3−62.70 (10)
C5—C1—C2—C313.23 (12)C1—C7—C8—O3178.37 (8)
C1—C2—C3—C4−20.30 (13)C10—O4—C9—O3−63.98 (14)
C2—C3—C4—O1−156.31 (13)C8—O3—C9—O4−60.59 (13)
C2—C3—C4—C520.54 (14)C7—O2—C11—O56.45 (18)
O1—C4—C5—C1164.54 (12)C7—O2—C11—C12−173.72 (8)
C3—C4—C5—C1−12.34 (13)O5—C11—C12—C17179.13 (13)
O1—C4—C5—C6−132.77 (13)O2—C11—C12—C17−0.71 (15)
C3—C4—C5—C650.36 (13)O5—C11—C12—C13−1.43 (19)
C6—C1—C5—C4109.58 (11)O2—C11—C12—C13178.73 (9)
C7—C1—C5—C4−142.96 (10)C17—C12—C13—C140.32 (17)
C2—C1—C5—C4−0.81 (12)C11—C12—C13—C14−179.12 (10)
C7—C1—C5—C6107.46 (10)C12—C13—C14—C15−0.23 (16)
C2—C1—C5—C6−110.39 (10)C13—C14—C15—C16−0.01 (17)
C7—C1—C6—C5−108.79 (10)C13—C14—C15—N179.31 (10)
C2—C1—C6—C597.02 (11)O6—N—C15—C16−173.37 (11)
C4—C5—C6—C1−95.56 (11)O7—N—C15—C166.64 (16)
C11—O2—C7—C1−120.22 (10)O6—N—C15—C147.28 (16)
C11—O2—C7—C8117.82 (10)O7—N—C15—C14−172.71 (11)
C6—C1—C7—O2155.15 (9)C14—C15—C16—C170.16 (18)
C5—C1—C7—O285.13 (11)N—C15—C16—C17−179.17 (10)
C2—C1—C7—O2−51.99 (12)C15—C16—C17—C12−0.07 (18)
C6—C1—C7—C8−87.05 (11)C13—C12—C17—C16−0.17 (18)
C5—C1—C7—C8−157.06 (9)C11—C12—C17—C16179.26 (11)
C2—C1—C7—C865.82 (12)

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: LH2582).

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