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

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ISSN: 2056-9890

(S)-3-Acetyl-3-[(R)-1-(4-bromo­phen­yl)-2-nitro­eth­yl]oxolan-2-one

aCatalytic Hydrogenation Research Center, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China, and bHangzhou Minsheng Pharmaceutical Group Co. Ltd, Hangzhou, People's Republic of China
*Correspondence e-mail: chrc@zjut.edu.cn

(Received 18 November 2011; accepted 1 December 2011; online 14 December 2011)

The title compound, C14H14BrNO5, has two chiral C atoms. The quaternary C atom in the oxolanone ring has an S configuration, while the adjacent tertiary C atom has an R configuration. The oxolanone ring adopts an envelope conformation, with the flap C atom lying 0.298 (3) Å from the mean plane of the remaining four atoms. In the crystal, mol­ecules are connected into chains along [010] via weak C—H⋯O hydrogen bonds.

Related literature

For general background, see: Li et al. (2009[Li, N., Xi, G. H., Wu, Q. H., Liu, W. H., Ma, J. J. & Wang, C. (2009). Chin. J. Org. Chem. 29, 1018-1038.]), Malerich et al. (2008[Malerich, J. P., Hagihara, K. & Rawal, V. H. (2008). J. Am. Chem. Soc. 130, 14416-14417.]); For related structures, see: Li et al. (2005[Li, H. M., Wang, Y., Tang, L., Wu, F. H., Liu, X. F., Guo, C. Y., Foxman, B. M. & Deng, L. (2005). Angew. Chem. Int. Ed. 44, 105-108.]).

[Scheme 1]

Experimental

Crystal data
  • C14H14BrNO5

  • Mr = 356.17

  • Monoclinic, P 21

  • a = 9.6237 (7) Å

  • b = 6.6547 (4) Å

  • c = 12.0503 (8) Å

  • β = 105.794 (2)°

  • V = 742.60 (9) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 2.79 mm−1

  • T = 296 K

  • 0.43 × 0.27 × 0.22 mm

Data collection
  • Rigaku R-AXIS RAPID/ZJUG diffractometer

  • Absorption correction: multi-scan (ABSCOR; Higashi, 1995[Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.301, Tmax = 0.542

  • 7336 measured reflections

  • 3272 independent reflections

  • 1893 reflections with I > 2σ(I)

  • Rint = 0.041

Refinement
  • R[F2 > 2σ(F2)] = 0.033

  • wR(F2) = 0.104

  • S = 1.00

  • 3272 reflections

  • 192 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.45 e Å−3

  • Δρmin = −0.45 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1327 Friedel pairs

  • Flack parameter: 0.014 (14)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C11—H11⋯O5i 0.93 2.58 3.306 (2) 135
C10—H10⋯O3ii 0.93 2.63 3.514 (2) 158
Symmetry codes: (i) x, y-1, z; (ii) [-x+1, y-{\script{1\over 2}}, -z+1].

Data collection: PROCESS-AUTO (Rigaku, 2006[Rigaku (2006). PROCESS_AUTO. Rigaku Corporation, Tokyo, Japan.]); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku, 2007[Rigaku (2007). CrystalStructure. Rigaku Americas, The Woodlands, Texas, USA.]); 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 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

The organocatalytic Michael reaction is often regarded as one of the most efficient and broadly applicable carbon-carbon bond-forming reactions. One of the most studied reactions is the Michael addition of 1,3-dicarbonyl compounds to nitroolefins because the highly functionalized nitro compounds are versatile intermediates in organic synthesis. The title compound, which was readily synthesized by the organocatalytic Michael reaction of 3-acetyldihydrofuran-2(3H)-one to (E)-1-bromo-4-(2-nitrovinyl)benzene, could act as an intermediate in organic and natural product synthesis. In this article, the crystal structure of the title compoud (S)-3-acetyl-3-((R) -1-(4-bromophenyl)-2-nitroethyl)dihydrofuran-2(3H)-one is described (Fig. 1). The structure has two chiral centers. The quaternary carbon in the oxolanone ring of the title compound adopts an S configuration, while the adjacent tertiary carbon atom has R configuration. The oxolanone ring displays an envelope conformation, with the flap carbon atom lying 0.298 (3) Å from the mean plane of the remaining four atoms. In the crystal, molecules are connected into chains along the b axis direction by weak C11—H11···O5i and C10—H10···O3ii hydrogen bonds [Symmetry code: (i)x, -1 + y, z; (ii) 1 - x, -1/2 + y, 1 - z] (Fig. 2).

Related literature top

For general background [to what?], see: Li et al. (2009), Malerich et al. (2008); For related structures, see: Li et al. (2005).

Experimental top

To a solution of (E)-1-bromo-4-(2-nitrovinyl)benzene (1 mmol) and 3-acetyldihydrofuran-2(3H)-one (1 mmol) in 1,4-dioxane (3 ml) was added 3-((1S)-(6-methoxyquinolin-4-yl) (8-vinylquinuclidin-2-yl)methylamino)-4- ((S)-1-phenylethylamino)cyclobut -3-ene-1,2-dione(0.025 mmol) as catalyst, and the mixture was stirred at room temperature for 12 h (monitored by TLC). Then the solvent was distilled under vacuum, and the residue was purified by flash column chromatography (silica gel, Hex/AcOEt, v/v, 3:1) giving the title compound. Single crystals were obtained by slow evaporation of a CH2Cl2 and iPrOH solution.

Refinement top

H atoms were placed in calculated positions with C—H = 0.98 (1) Å (sp), C—H = 0.97 (1) Å (sp2), C—H = 0.96 (1) Å (sp3), C—H = 0.93 (1) Å (aromatic). All H atoms included in the final cycles of refinement using a riding model, with Uiso(H) = 1.2Ueq or 1.5Ueq (sp3) of the carrier atoms.

Computing details top

Data collection: PROCESS-AUTO (Rigaku, 2006); cell refinement: PROCESS-AUTO (Rigaku, 2006); data reduction: CrystalStructure (Rigaku, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. A view showing infinite chains with C11—H11···O5i and C10—H10···O3ii hydrogen bonds [Symmetry code: (i) x, -1 + y, z; (ii) 1 - x, -1/2 + y, 1 - z].
(S)-3-Acetyl-3-[(R)-1-(4-bromophenyl)-2-nitroethyl]oxolan-2-one top
Crystal data top
C14H14BrNO5F(000) = 360
Mr = 356.17Dx = 1.593 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 5006 reflections
a = 9.6237 (7) Åθ = 3.1–27.4°
b = 6.6547 (4) ŵ = 2.79 mm1
c = 12.0503 (8) ÅT = 296 K
β = 105.794 (2)°Block, colourless
V = 742.60 (9) Å30.43 × 0.27 × 0.22 mm
Z = 2
Data collection top
Rigaku R-AXIS RAPID/ZJUG
diffractometer
3272 independent reflections
Radiation source: rotating anode1893 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.041
Detector resolution: 10.00 pixels mm-1θmax = 27.4°, θmin = 3.2°
ω scansh = 1212
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
k = 88
Tmin = 0.301, Tmax = 0.542l = 1515
7336 measured reflections
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.033 w = 1/[σ2(Fo2) + (0.0212P)2 + 0.6532P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.104(Δ/σ)max < 0.001
S = 1.00Δρmax = 0.45 e Å3
3272 reflectionsΔρmin = 0.45 e Å3
192 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
1 restraintExtinction coefficient: 0.013 (2)
Primary atom site location: structure-invariant direct methodsAbsolute structure: Flack (1983), 1327 Friedel pairs
Secondary atom site location: difference Fourier mapAbsolute structure parameter: 0.014 (14)
Crystal data top
C14H14BrNO5V = 742.60 (9) Å3
Mr = 356.17Z = 2
Monoclinic, P21Mo Kα radiation
a = 9.6237 (7) ŵ = 2.79 mm1
b = 6.6547 (4) ÅT = 296 K
c = 12.0503 (8) Å0.43 × 0.27 × 0.22 mm
β = 105.794 (2)°
Data collection top
Rigaku R-AXIS RAPID/ZJUG
diffractometer
3272 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
1893 reflections with I > 2σ(I)
Tmin = 0.301, Tmax = 0.542Rint = 0.041
7336 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.033H-atom parameters constrained
wR(F2) = 0.104Δρmax = 0.45 e Å3
S = 1.00Δρmin = 0.45 e Å3
3272 reflectionsAbsolute structure: Flack (1983), 1327 Friedel pairs
192 parametersAbsolute structure parameter: 0.014 (14)
1 restraint
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
Br10.01386 (6)0.39571 (12)0.91217 (5)0.0776 (3)
O10.6151 (4)0.8445 (6)0.9285 (3)0.0692 (12)
O20.5776 (5)1.1368 (6)0.8363 (4)0.0713 (12)
O30.6176 (3)0.9028 (8)0.5481 (3)0.0608 (8)
O40.2157 (5)0.9380 (9)0.4296 (4)0.0967 (17)
O50.1045 (5)1.0968 (9)0.5321 (5)0.121 (2)
N10.2123 (6)1.0229 (7)0.5175 (4)0.0647 (12)
C10.4009 (5)0.8284 (6)0.6525 (4)0.0429 (11)
H10.39540.74780.58330.051*
C20.5624 (5)0.8272 (6)0.7251 (4)0.0424 (11)
C30.6125 (6)0.6151 (8)0.7740 (5)0.0550 (13)
H3A0.54560.51240.73460.066*
H3B0.70800.58460.76650.066*
C40.6136 (8)0.6296 (10)0.9003 (5)0.0751 (18)
H4A0.52840.56550.91250.090*
H4B0.69850.56360.94870.090*
C50.5860 (5)0.9572 (8)0.8336 (4)0.0524 (14)
C60.6619 (5)0.8984 (11)0.6521 (4)0.0505 (10)
C70.8152 (6)0.9490 (11)0.7133 (5)0.085 (2)
H7A0.87860.88420.67520.127*
H7B0.83680.90350.79170.127*
H7C0.82861.09190.71210.127*
C80.3494 (6)1.0384 (8)0.6113 (4)0.0506 (13)
H8A0.33361.11620.67490.061*
H8B0.42211.10620.58290.061*
C90.2998 (5)0.7295 (7)0.7150 (4)0.0421 (11)
C100.2338 (5)0.5493 (7)0.6755 (4)0.0494 (12)
H100.24790.49340.60870.059*
C110.1475 (5)0.4496 (7)0.7317 (4)0.0528 (13)
H110.10460.32770.70420.063*
C120.1266 (5)0.5352 (8)0.8298 (4)0.0498 (12)
C130.1879 (6)0.7160 (9)0.8705 (5)0.0616 (15)
H130.17210.77210.93670.074*
C140.2725 (6)0.8132 (7)0.8127 (4)0.0548 (13)
H140.31240.93730.83930.066*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0668 (3)0.1015 (5)0.0779 (4)0.0184 (4)0.0426 (3)0.0001 (4)
O10.077 (2)0.091 (4)0.0396 (18)0.004 (2)0.0162 (17)0.010 (2)
O20.089 (3)0.052 (3)0.070 (3)0.007 (2)0.018 (2)0.014 (2)
O30.073 (2)0.0688 (19)0.0500 (18)0.006 (3)0.0329 (16)0.001 (3)
O40.105 (3)0.120 (5)0.054 (2)0.013 (3)0.002 (2)0.020 (3)
O50.070 (3)0.150 (5)0.124 (4)0.035 (3)0.005 (3)0.052 (4)
N10.070 (3)0.059 (3)0.059 (3)0.004 (2)0.008 (3)0.001 (2)
C10.051 (3)0.039 (3)0.043 (2)0.002 (2)0.020 (2)0.001 (2)
C20.051 (3)0.037 (2)0.045 (2)0.0014 (19)0.023 (2)0.0041 (19)
C30.050 (3)0.052 (3)0.067 (3)0.005 (2)0.024 (3)0.012 (3)
C40.081 (5)0.073 (4)0.073 (4)0.012 (3)0.024 (4)0.029 (4)
C50.048 (3)0.065 (4)0.046 (3)0.003 (2)0.016 (2)0.003 (2)
C60.054 (3)0.046 (2)0.057 (3)0.003 (3)0.025 (2)0.001 (3)
C70.062 (3)0.119 (7)0.079 (4)0.024 (4)0.028 (3)0.001 (4)
C80.055 (3)0.042 (3)0.052 (3)0.003 (3)0.010 (3)0.001 (2)
C90.043 (3)0.041 (2)0.046 (3)0.001 (2)0.017 (2)0.000 (2)
C100.057 (3)0.048 (3)0.049 (3)0.007 (2)0.025 (2)0.012 (2)
C110.053 (3)0.053 (3)0.059 (3)0.003 (2)0.027 (2)0.006 (2)
C120.039 (3)0.064 (3)0.050 (3)0.002 (2)0.019 (2)0.002 (3)
C130.054 (3)0.083 (4)0.056 (3)0.009 (3)0.028 (3)0.020 (3)
C140.062 (3)0.056 (3)0.056 (3)0.013 (2)0.033 (3)0.021 (2)
Geometric parameters (Å, º) top
Br1—C121.900 (5)C4—H4A0.9700
O1—C51.332 (6)C4—H4B0.9700
O1—C41.470 (8)C6—C71.497 (7)
O2—C51.199 (6)C7—H7A0.9600
O3—C61.210 (5)C7—H7B0.9600
O4—N11.208 (6)C7—H7C0.9600
O5—N11.204 (6)C8—H8A0.9700
N1—C81.489 (7)C8—H8B0.9700
C1—C81.521 (6)C9—C101.380 (6)
C1—C91.532 (6)C9—C141.391 (6)
C1—C21.562 (7)C10—C111.376 (7)
C1—H10.9800C10—H100.9300
C2—C51.532 (6)C11—C121.375 (7)
C2—C61.541 (6)C11—H110.9300
C2—C31.555 (6)C12—C131.371 (7)
C3—C41.522 (8)C13—C141.369 (7)
C3—H3A0.9700C13—H130.9300
C3—H3B0.9700C14—H140.9300
C5—O1—C4111.3 (4)O3—C6—C2120.0 (4)
O5—N1—O4123.4 (5)C7—C6—C2118.1 (4)
O5—N1—C8118.7 (5)C6—C7—H7A109.5
O4—N1—C8117.9 (5)C6—C7—H7B109.5
C8—C1—C9111.2 (4)H7A—C7—H7B109.5
C8—C1—C2111.9 (4)C6—C7—H7C109.5
C9—C1—C2113.0 (4)H7A—C7—H7C109.5
C8—C1—H1106.8H7B—C7—H7C109.5
C9—C1—H1106.8N1—C8—C1109.1 (4)
C2—C1—H1106.8N1—C8—H8A109.9
C5—C2—C6110.0 (4)C1—C8—H8A109.9
C5—C2—C3103.3 (4)N1—C8—H8B109.9
C6—C2—C3108.6 (4)C1—C8—H8B109.9
C5—C2—C1111.7 (4)H8A—C8—H8B108.3
C6—C2—C1110.9 (4)C10—C9—C14117.7 (4)
C3—C2—C1112.1 (4)C10—C9—C1119.9 (4)
C4—C3—C2103.8 (4)C14—C9—C1122.4 (4)
C4—C3—H3A111.0C11—C10—C9122.1 (5)
C2—C3—H3A111.0C11—C10—H10118.9
C4—C3—H3B111.0C9—C10—H10118.9
C2—C3—H3B111.0C10—C11—C12118.2 (5)
H3A—C3—H3B109.0C10—C11—H11120.9
O1—C4—C3106.8 (4)C12—C11—H11120.9
O1—C4—H4A110.4C13—C12—C11121.4 (5)
C3—C4—H4A110.4C13—C12—Br1119.5 (4)
O1—C4—H4B110.4C11—C12—Br1119.0 (4)
C3—C4—H4B110.4C14—C13—C12119.4 (5)
H4A—C4—H4B108.6C14—C13—H13120.3
O2—C5—O1122.5 (5)C12—C13—H13120.3
O2—C5—C2126.2 (5)C13—C14—C9121.1 (5)
O1—C5—C2111.3 (4)C13—C14—H14119.5
O3—C6—C7121.8 (4)C9—C14—H14119.5
C8—C1—C2—C560.9 (5)C5—C2—C6—C743.1 (7)
C9—C1—C2—C565.5 (5)C3—C2—C6—C769.3 (7)
C8—C1—C2—C662.2 (5)C1—C2—C6—C7167.1 (5)
C9—C1—C2—C6171.4 (4)O5—N1—C8—C1117.9 (6)
C8—C1—C2—C3176.3 (4)O4—N1—C8—C162.9 (7)
C9—C1—C2—C349.8 (5)C9—C1—C8—N168.4 (5)
C5—C2—C3—C417.2 (5)C2—C1—C8—N1164.2 (4)
C6—C2—C3—C4133.9 (5)C8—C1—C9—C10121.9 (5)
C1—C2—C3—C4103.2 (5)C2—C1—C9—C10111.2 (5)
C5—O1—C4—C312.5 (7)C8—C1—C9—C1459.0 (6)
C2—C3—C4—O118.2 (6)C2—C1—C9—C1467.8 (6)
C4—O1—C5—O2177.8 (5)C14—C9—C10—C112.3 (7)
C4—O1—C5—C20.8 (6)C1—C9—C10—C11176.8 (5)
C6—C2—C5—O254.9 (7)C9—C10—C11—C120.6 (8)
C3—C2—C5—O2170.7 (5)C10—C11—C12—C130.8 (8)
C1—C2—C5—O268.7 (7)C10—C11—C12—Br1177.7 (4)
C6—C2—C5—O1126.5 (4)C11—C12—C13—C140.4 (8)
C3—C2—C5—O110.8 (5)Br1—C12—C13—C14178.1 (4)
C1—C2—C5—O1109.9 (4)C12—C13—C14—C91.4 (9)
C5—C2—C6—O3140.6 (6)C10—C9—C14—C132.7 (8)
C3—C2—C6—O3107.0 (7)C1—C9—C14—C13176.4 (5)
C1—C2—C6—O316.5 (8)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11···O5i0.932.583.306 (2)135
C10—H10···O3ii0.932.633.514 (2)158
Symmetry codes: (i) x, y1, z; (ii) x+1, y1/2, z+1.

Experimental details

Crystal data
Chemical formulaC14H14BrNO5
Mr356.17
Crystal system, space groupMonoclinic, P21
Temperature (K)296
a, b, c (Å)9.6237 (7), 6.6547 (4), 12.0503 (8)
β (°) 105.794 (2)
V3)742.60 (9)
Z2
Radiation typeMo Kα
µ (mm1)2.79
Crystal size (mm)0.43 × 0.27 × 0.22
Data collection
DiffractometerRigaku R-AXIS RAPID/ZJUG
diffractometer
Absorption correctionMulti-scan
(ABSCOR; Higashi, 1995)
Tmin, Tmax0.301, 0.542
No. of measured, independent and
observed [I > 2σ(I)] reflections
7336, 3272, 1893
Rint0.041
(sin θ/λ)max1)0.648
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.033, 0.104, 1.00
No. of reflections3272
No. of parameters192
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.45, 0.45
Absolute structureFlack (1983), 1327 Friedel pairs
Absolute structure parameter0.014 (14)

Computer programs: PROCESS-AUTO (Rigaku, 2006), CrystalStructure (Rigaku, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11···O5i0.9302.5803.306 (2)135
C10—H10···O3ii0.9302.6333.514 (2)158
Symmetry codes: (i) x, y1, z; (ii) x+1, y1/2, z+1.
 

Acknowledgements

This work was supported by the Zhejiang Provincial Natural Science Foundation of China (No. Y4110373) and the Foundation of Zhejiang Education Committee (No. Y201018458). We are also grateful for the help of Professor Jian-Ming Gu of Zhejiang University.

References

First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals
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