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ISSN: 2056-9890

(2S,3R)-3-(2-Bromo­phen­yl)-2-nitro-2,3,6,7-tetra­hydro-1-benzo­furan-4(5H)-one

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

(Received 17 June 2013; accepted 27 June 2013; online 3 July 2013)

The title compound, C14H12BrNO4, has two chiral C atoms. The C atom next to the O atom in the di­hydro­furan ring has an S configuration, while the adjacent chiral C atom has an R configuration. The cyclo­hex-2-enone and di­hydro­furan rings both adopt envelope conformations, with the flap atoms (middle CH2 in cyclo­hex-2-enone and NO2-substituted C in di­hydro­furan) lying 0.612 (3) and 0.295 (2) Å, respectively, from the mean plane of the remaining atoms. The dihedral angle between the mean planes of the furan and benzene rings is 80.0 (3)°. In the crystal, the mol­ecules are linked by C—H⋯O inter­actions, generating a three-dimensional network.

Related literature

For global background on functionalized 2,3-di­hydro­furans, see: Fan et al. (2010[Fan, L. P., Li, P., Li, X. S., Xu, D. C., Ge, M. M., Zhu, W. D. & Xie, J. W. (2010). J. Org. Chem. 75, 8716-8719.]); Rueping et al. (2010[Rueping, M., Parra, A., Uria, U., Besselievre, F. & Merino, E. (2010). Org. Lett. 12, 5680-5683.]). The absolute configuration was assigned by the method of Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]).

[Scheme 1]

Experimental

Crystal data
  • C14H12BrNO4

  • Mr = 338.16

  • Orthorhombic, P 21 21 21

  • a = 7.2162 (8) Å

  • b = 7.3372 (8) Å

  • c = 25.9727 (13) Å

  • V = 1375.2 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 3.00 mm−1

  • T = 296 K

  • 0.54 × 0.31 × 0.23 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 = 0.334, Tmax = 0.505

  • 10897 measured reflections

  • 2548 independent reflections

  • 1456 reflections with I > 2σ(I)

  • Rint = 0.068

Refinement
  • R[F2 > 2σ(F2)] = 0.059

  • wR(F2) = 0.125

  • S = 1.00

  • 2548 reflections

  • 182 parameters

  • H-atom parameters constrained

  • Δρmax = 0.51 e Å−3

  • Δρmin = −0.57 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1041 Friedel pairs

  • Flack parameter: 0.03 (2)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C1—H1⋯O1i 0.98 2.51 3.486 (12) 171
C7—H7A⋯O3ii 0.97 2.66 3.403 (12) 134
C7—H7B⋯O3iii 0.97 2.52 3.480 (13) 172
Symmetry codes: (i) x+1, y, z; (ii) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1]; (iii) x, y+1, z.

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, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information


Comment top

The highly functionalized 2,3-dihydrofurans are very important compounds that may serve as precursors for the construction of pharmacologically important chemicals. Organocatalytic asymmetric reactions have been used as efficient tools for the synthesis of chiral compounds under mild conditions. The title compound, which was readily synthesized by the organocatalytic Michael-SN2 reaction of cyclohexane-1,3-dione to (E)-1-bromo-2-(2-bromo-2-nitrovinyl)benzene, could act as an intermediate in organic and natural product synthesis. In this article, the crystal structure of the title compound (2S,3R)-3-(2-bromophenyl)-2-nitro-2,3,6,7- tetrahydrobenzofuran-4(5H)-one is described (Fig. 1). The structure has two chiral centers. The carbon next to the oxygen atom in the dihydrofuran ring has S configuration, while the adjacent chiral carbon atom has R configuration. Both the cyclohex-2-enone ring and dihydrofurane ring adopt envelope conformations, with the flap carbon atom lying 0.612 (3) Å and 0.295 (2) Å respectively on either side of the mean plane of the remaining fused-ring atoms. The dihedral angle between the mean plane of the furan ring and the benzene ring is 80.0 (3)°.

Related literature top

For global background on functionalized 2,3-dihydrofurans, see: Fan et al. (2010); Rueping et al. (2010). The absolute configuration was assigned by the method of Flack (1983).

Experimental top

To a solution of cyclohexane-1,3-dione (1.2 mmol) and (E)-1-bromo-2-(2-bromo-2-nitrovinyl)benzene (1 mmol) in CHCl3 (3 ml) was added (0.025 mmol) 1-(3,5-bis(trifluoromethyl)phenyl)-3-((S) -(6-methoxyquinolin-4-yl)((2S,4S,8R)-8-vinylquinuclidin-2 -yl)methyl)thiourea as catalyst and DIPEA (0.3 mmol) as the base. The mixture was stirred at room temperature for 12 h (monitored by TLC). Then the solvent was evaporated 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 (v/v, 1:1).

Refinement top

H atoms were placed in calculated positions with C—H = 0.98 Å (R3CH), C—H = 0.97 Å (R2CH2), C—H = 0.93 Å (aromatic). All H atoms included in the final cycles of refinement using a riding model, with Uiso(H) = 1.2Ueq 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, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).

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. The molecular packing of the title compounds.
(2S,3R)-3-(2-Bromophenyl)-2-nitro-2,3,6,7-tetrahydro-1-benzofuran-4(5H)-one top
Crystal data top
C14H12BrNO4F(000) = 680
Mr = 338.16Dx = 1.633 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 6447 reflections
a = 7.2162 (8) Åθ = 3.1–27.4°
b = 7.3372 (8) ŵ = 3.00 mm1
c = 25.9727 (13) ÅT = 296 K
V = 1375.2 (2) Å3Needle, colorless
Z = 40.54 × 0.31 × 0.23 mm
Data collection top
Rigaku R-AXIS RAPID/ZJUG
diffractometer
2548 independent reflections
Radiation source: rotating anode1456 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.068
Detector resolution: 10.00 pixels mm-1θmax = 25.5°, θmin = 3.1°
ω scansh = 88
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
k = 87
Tmin = 0.334, Tmax = 0.505l = 3131
10897 measured reflections
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.059 w = 1/[σ2(Fo2) + (0.0081P)2 + 2.5658P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.125(Δ/σ)max < 0.001
S = 1.00Δρmax = 0.51 e Å3
2548 reflectionsΔρmin = 0.57 e Å3
182 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.0117 (17)
Primary atom site location: structure-invariant direct methodsAbsolute structure: Flack (1983), 1041 Friedel pairs
Secondary atom site location: difference Fourier mapAbsolute structure parameter: 0.03 (2)
Crystal data top
C14H12BrNO4V = 1375.2 (2) Å3
Mr = 338.16Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 7.2162 (8) ŵ = 3.00 mm1
b = 7.3372 (8) ÅT = 296 K
c = 25.9727 (13) Å0.54 × 0.31 × 0.23 mm
Data collection top
Rigaku R-AXIS RAPID/ZJUG
diffractometer
2548 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
1456 reflections with I > 2σ(I)
Tmin = 0.334, Tmax = 0.505Rint = 0.068
10897 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.059H-atom parameters constrained
wR(F2) = 0.125Δρmax = 0.51 e Å3
S = 1.00Δρmin = 0.57 e Å3
2548 reflectionsAbsolute structure: Flack (1983), 1041 Friedel pairs
182 parametersAbsolute structure parameter: 0.03 (2)
0 restraints
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
C10.7398 (10)0.3494 (8)0.5784 (2)0.0619 (16)
H10.86100.33770.59520.074*
C20.5793 (7)0.3053 (8)0.6169 (2)0.0516 (15)
H20.52700.18470.60980.062*
C30.4449 (7)0.4531 (9)0.6016 (2)0.0492 (14)
C40.2478 (9)0.4690 (8)0.6141 (2)0.0569 (14)
C50.1536 (9)0.6322 (9)0.5902 (2)0.0660 (19)
H5A0.05500.67150.61310.079*
H5B0.09680.59440.55810.079*
C60.2792 (9)0.7952 (8)0.5794 (2)0.0677 (18)
H6A0.31870.84880.61170.081*
H6B0.21020.88670.56040.081*
C70.4499 (9)0.7389 (9)0.5482 (2)0.0660 (18)
H7A0.41540.71670.51260.079*
H7B0.54160.83550.54890.079*
C80.5265 (8)0.5737 (9)0.5708 (2)0.0506 (15)
C90.6438 (8)0.3183 (8)0.6723 (2)0.0532 (15)
C100.6320 (9)0.4785 (10)0.7000 (3)0.0721 (19)
H100.57340.57810.68500.087*
C110.7034 (10)0.4972 (12)0.7491 (3)0.085 (2)
H110.69760.60760.76660.102*
C120.7845 (11)0.3438 (16)0.7712 (3)0.098 (3)
H120.83020.35140.80460.118*
C130.7987 (11)0.1840 (14)0.7455 (4)0.096 (3)
H130.85240.08360.76150.116*
C140.7336 (10)0.1696 (8)0.6957 (3)0.0698 (18)
N10.7257 (12)0.2243 (10)0.5319 (3)0.091 (2)
O10.1679 (6)0.3594 (7)0.64055 (19)0.0816 (14)
O20.7098 (5)0.5307 (6)0.56089 (15)0.0623 (12)
O30.7909 (12)0.0725 (9)0.5383 (3)0.147 (3)
O40.6648 (14)0.2703 (15)0.4940 (3)0.211 (5)
Br10.75326 (16)0.05596 (11)0.66299 (5)0.1322 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.042 (3)0.072 (4)0.073 (4)0.007 (4)0.004 (4)0.006 (3)
C20.046 (3)0.053 (3)0.057 (4)0.010 (3)0.002 (3)0.004 (3)
C30.046 (3)0.064 (4)0.037 (3)0.008 (3)0.001 (3)0.002 (3)
C40.051 (3)0.069 (4)0.051 (3)0.004 (4)0.005 (3)0.003 (3)
C50.057 (4)0.090 (5)0.051 (4)0.003 (4)0.007 (3)0.000 (4)
C60.067 (5)0.062 (4)0.074 (4)0.004 (4)0.013 (4)0.005 (3)
C70.072 (5)0.068 (4)0.058 (4)0.008 (4)0.014 (4)0.012 (3)
C80.050 (3)0.061 (4)0.040 (3)0.010 (3)0.005 (3)0.003 (3)
C90.045 (3)0.059 (4)0.056 (4)0.006 (3)0.001 (3)0.006 (3)
C100.070 (4)0.087 (5)0.059 (4)0.006 (4)0.003 (4)0.006 (4)
C110.082 (5)0.112 (7)0.061 (5)0.004 (5)0.009 (4)0.012 (4)
C120.070 (6)0.180 (9)0.044 (4)0.010 (6)0.014 (4)0.026 (6)
C130.071 (6)0.123 (7)0.095 (7)0.000 (6)0.016 (5)0.036 (6)
C140.050 (4)0.074 (4)0.085 (5)0.009 (4)0.005 (4)0.014 (4)
N10.098 (5)0.091 (5)0.082 (5)0.002 (5)0.033 (4)0.027 (4)
O10.056 (3)0.104 (4)0.085 (3)0.014 (3)0.010 (2)0.022 (3)
O20.047 (3)0.071 (3)0.068 (3)0.009 (2)0.012 (2)0.001 (2)
O30.195 (8)0.093 (4)0.152 (6)0.001 (6)0.066 (6)0.038 (4)
O40.293 (12)0.231 (9)0.108 (6)0.139 (9)0.073 (7)0.096 (6)
Br10.1192 (8)0.0727 (5)0.2046 (12)0.0255 (6)0.0517 (9)0.0010 (6)
Geometric parameters (Å, º) top
C1—O21.423 (7)C7—C81.455 (8)
C1—N11.520 (8)C7—H7A0.9700
C1—C21.563 (8)C7—H7B0.9700
C1—H10.9800C8—O21.384 (7)
C2—C31.507 (8)C9—C101.381 (9)
C2—C91.517 (8)C9—C141.407 (8)
C2—H20.9800C10—C111.382 (9)
C3—C81.332 (8)C10—H100.9300
C3—C41.463 (8)C11—C121.393 (11)
C4—O11.205 (6)C11—H110.9300
C4—C51.510 (8)C12—C131.352 (11)
C5—C61.527 (8)C12—H120.9300
C5—H5A0.9700C13—C141.380 (10)
C5—H5B0.9700C13—H130.9300
C6—C71.531 (9)C14—Br11.866 (7)
C6—H6A0.9700N1—O41.130 (9)
C6—H6B0.9700N1—O31.221 (9)
O2—C1—N1107.4 (5)C8—C7—H7A110.0
O2—C1—C2106.5 (5)C6—C7—H7A110.0
N1—C1—C2109.5 (5)C8—C7—H7B110.0
O2—C1—H1111.1C6—C7—H7B110.0
N1—C1—H1111.1H7A—C7—H7B108.4
C2—C1—H1111.1C3—C8—O2112.5 (6)
C3—C2—C9113.7 (5)C3—C8—C7129.0 (6)
C3—C2—C199.3 (5)O2—C8—C7118.5 (5)
C9—C2—C1111.5 (5)C10—C9—C14117.6 (6)
C3—C2—H2110.7C10—C9—C2121.9 (6)
C9—C2—H2110.7C14—C9—C2120.2 (6)
C1—C2—H2110.7C9—C10—C11122.8 (7)
C8—C3—C4120.6 (6)C9—C10—H10118.6
C8—C3—C2110.6 (5)C11—C10—H10118.6
C4—C3—C2128.7 (5)C10—C11—C12117.2 (7)
O1—C4—C3122.5 (6)C10—C11—H11121.4
O1—C4—C5123.2 (6)C12—C11—H11121.4
C3—C4—C5114.3 (6)C13—C12—C11121.9 (7)
C4—C5—C6115.4 (5)C13—C12—H12119.0
C4—C5—H5A108.4C11—C12—H12119.0
C6—C5—H5A108.4C12—C13—C14120.2 (8)
C4—C5—H5B108.4C12—C13—H13119.9
C6—C5—H5B108.4C14—C13—H13119.9
H5A—C5—H5B107.5C13—C14—C9120.1 (7)
C5—C6—C7111.4 (5)C13—C14—Br1118.0 (6)
C5—C6—H6A109.4C9—C14—Br1121.7 (5)
C7—C6—H6A109.4O4—N1—O3122.7 (9)
C5—C6—H6B109.4O4—N1—C1122.6 (8)
C7—C6—H6B109.4O3—N1—C1114.7 (8)
H6A—C6—H6B108.0C8—O2—C1107.4 (5)
C8—C7—C6108.5 (5)
O2—C1—C2—C317.9 (6)C1—C2—C9—C1090.7 (7)
N1—C1—C2—C398.0 (6)C3—C2—C9—C14165.2 (5)
O2—C1—C2—C9102.2 (6)C1—C2—C9—C1483.6 (7)
N1—C1—C2—C9142.0 (6)C14—C9—C10—C110.2 (10)
C9—C2—C3—C8107.2 (6)C2—C9—C10—C11174.6 (6)
C1—C2—C3—C811.3 (6)C9—C10—C11—C122.2 (11)
C9—C2—C3—C476.5 (7)C10—C11—C12—C132.0 (13)
C1—C2—C3—C4165.1 (5)C11—C12—C13—C140.7 (14)
C8—C3—C4—O1177.6 (6)C12—C13—C14—C93.2 (12)
C2—C3—C4—O11.6 (9)C12—C13—C14—Br1178.8 (7)
C8—C3—C4—C51.4 (8)C10—C9—C14—C133.0 (10)
C2—C3—C4—C5177.5 (5)C2—C9—C14—C13177.5 (6)
O1—C4—C5—C6153.7 (6)C10—C9—C14—Br1178.4 (5)
C3—C4—C5—C627.3 (7)C2—C9—C14—Br17.1 (8)
C4—C5—C6—C752.2 (7)O2—C1—N1—O414.4 (12)
C5—C6—C7—C845.7 (7)C2—C1—N1—O4101.0 (11)
C4—C3—C8—O2176.3 (5)O2—C1—N1—O3163.3 (7)
C2—C3—C8—O20.4 (7)C2—C1—N1—O381.4 (9)
C4—C3—C8—C74.9 (10)C3—C8—O2—C112.2 (6)
C2—C3—C8—C7178.4 (6)C7—C8—O2—C1168.9 (5)
C6—C7—C8—C319.8 (9)N1—C1—O2—C898.3 (6)
C6—C7—C8—O2158.9 (5)C2—C1—O2—C819.0 (6)
C3—C2—C9—C1020.5 (8)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···O1i0.982.513.486 (12)171
C7—H7A···O3ii0.972.663.403 (12)134
C7—H7B···O3iii0.972.523.480 (13)172
Symmetry codes: (i) x+1, y, z; (ii) x1/2, y+1/2, z+1; (iii) x, y+1, z.

Experimental details

Crystal data
Chemical formulaC14H12BrNO4
Mr338.16
Crystal system, space groupOrthorhombic, P212121
Temperature (K)296
a, b, c (Å)7.2162 (8), 7.3372 (8), 25.9727 (13)
V3)1375.2 (2)
Z4
Radiation typeMo Kα
µ (mm1)3.00
Crystal size (mm)0.54 × 0.31 × 0.23
Data collection
DiffractometerRigaku R-AXIS RAPID/ZJUG
diffractometer
Absorption correctionMulti-scan
(ABSCOR; Higashi, 1995)
Tmin, Tmax0.334, 0.505
No. of measured, independent and
observed [I > 2σ(I)] reflections
10897, 2548, 1456
Rint0.068
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.059, 0.125, 1.00
No. of reflections2548
No. of parameters182
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.51, 0.57
Absolute structureFlack (1983), 1041 Friedel pairs
Absolute structure parameter0.03 (2)

Computer programs: PROCESS-AUTO (Rigaku, 2006), CrystalStructure (Rigaku,2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), WinGX (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···O1i0.982.513.486 (12)171.2
C7—H7A···O3ii0.972.663.403 (12)134.0
C7—H7B···O3iii0.972.523.480 (13)172.1
Symmetry codes: (i) x+1, y, z; (ii) x1/2, y+1/2, z+1; (iii) x, y+1, z.
 

Acknowledgements

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

References

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