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

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ISSN: 2056-9890

(2S,4S)-2-[(S,E)-2-Bromo-1-nitro­methyl-3-phenyl­all­yl]-4-methyl­cyclo­hexa­none

aState Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China, and bHangzhou Jiuyuan Gene Engineering Company Limited, Hangzhou 310014, People's Republic of China
*Correspondence e-mail: xiaaibao@zjut.edu.cn

(Received 15 March 2012; accepted 26 March 2012; online 31 March 2012)

The crystal structure of the title compoud, C17H20BrNO3, contains three chiral centers, which all exhibit an S configuration. The C=C double bond has an E conformation. The cyclo­hexane ring is in a chair conformation. In the crystal, mol­ecules are linked by weak N—O⋯Br inter­actions [O⋯Br = 3.136 (4) Å].

Related literature

For related compounds, see: Li et al. (2009[Li, Z., Guo, Y., Li, B. & Luo, S. (2009). Acta Cryst. E65, o2023.]); Wu et al. (2011[Wu, C., Zhao, L. & Xia, A.-B. (2011). Acta Cryst. E67, o1939.]). For the asymmetric Michael reaction, which allows for the formation of three contiguous asymmetric centers, see: Agarwal & Peddinti (2011[Agarwal, J. & Peddinti, R. K. (2011). Tetrahedron Lett. 52, 117-121.]); Lu et al. (2010[Lu, A. D., Wu, R. H., Wang, Y. M., Zhou, Z. H., Wu, G. P., Fang, J. X. & Tang, C. C. (2010). Eur. J. Org. Chem. pp. 2057-2061.]); Luo et al. (2007[Luo, S., Zhang, L., Mi, X., Qiao, Y. & Cheng, J.-P. (2007). J. Org. Chem. 72, 9350-9352.]).

[Scheme 1]

Experimental

Crystal data
  • C17H20BrNO3

  • Mr = 366.25

  • Orthorhombic, P 21 21 21

  • a = 7.0942 (5) Å

  • b = 13.7920 (11) Å

  • c = 17.3108 (13) Å

  • V = 1693.7 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 2.44 mm−1

  • T = 296 K

  • 0.40 × 0.38 × 0.30 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 = 0.377, Tmax = 0.481

  • 13310 measured reflections

  • 3829 independent reflections

  • 1967 reflections with I > 2σ(I)

  • Rint = 0.092

Refinement
  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.106

  • S = 0.91

  • 3829 reflections

  • 200 parameters

  • H-atom parameters constrained

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.35 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1625 Friedel pairs

  • Flack parameter: −0.019 (14)

Data collection: PROCESS-AUTO (Rigaku, 2006[Rigaku (2006). PROCESS-AUTO. Rigaku Americas Corporation, The Woodlands, Texas, USA.]); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku, 2007[Rigaku (2007). CrystalStructure. Rigaku Americas, The Woodlands, Texas, USA, and Rigaku Corporation, Tokyo, Japan.]); 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

Asymmetric Michael additions of aldehydes or ketones to nitroalkenes represent fundamental transformations which have wide applications in organic synthesis (Luo et al., 2007; Lu et al., 2010; Agarwal & Peddinti, 2011). On the other hand, alkenyl halides are present in a variety of natural products as well as in bioactive compounds. The title compound (Fig. 1) was obtained from the Michael addition of 4-methyl-cyclohexanone to (2-bromo-4-nitro-buta-1,3-dienyl)-benzene in our laboratory. The geometry compares well with other related structures (Li et al., 2009; Wu et al., 2011). In the title compound, the cyclohexyl ring adopts a chair conformation. The plane of the phenyl ring and the least-squares plane of the cyclohexyl moiety enclose an angle of 69.80 (3)°, while the plane through the nitro group and the adjacent C17 atom encloses an angle of 87.12 (3)° with the phenyl ring. The Br1—C9—C10—C11 torsion angle of 175.8 (4)° confirms the E configuration of the molecule with respect to the C9=C10 double bond. The molecules are linked by weak intermolecular N—O···Br interactions, the O···Br distance being 3.136 (4) Å.

Related literature top

For related compounds, see: Li et al. (2009); Wu et al. (2011). For the asymmetric Michael reaction, which allows for the formation of three contiguous asymmetric centers, see: Agarwal & Peddinti (2011); Lu et al. (2010); Luo et al. (2007).

Experimental top

A saturated brine (0.5 mL) solution of (2-bromo-4-nitrobuta-1,3-dienyl) benzene (1 mmol) and 4-methyl-cyclohexanone (1.2 mmol) was stirred with (S)-2-(pyrrolidin-2-ylmethylthio)pyridine (0.3 mmol) as catalyst and benzoic acid (0.3 mmol) as cocatalyst, at room temperature. After completion of the reaction, the mixture was extracted with ethyl acetate. Solvents were removed under vacuum and the residue was purified by column chromatography on silica gel (eluent: petroleum ether-ether). Suitable crystals were obtained by slow evaporation of an ethyl acetate solution.

Refinement top

H atoms were placed in calculated positions with C—H ranging from 0.93 to 0.98 Å and refined using riding model with Uiso(H)=1.2Ueq or 1.5Ueq of the carrier atoms.

Structure description top

Asymmetric Michael additions of aldehydes or ketones to nitroalkenes represent fundamental transformations which have wide applications in organic synthesis (Luo et al., 2007; Lu et al., 2010; Agarwal & Peddinti, 2011). On the other hand, alkenyl halides are present in a variety of natural products as well as in bioactive compounds. The title compound (Fig. 1) was obtained from the Michael addition of 4-methyl-cyclohexanone to (2-bromo-4-nitro-buta-1,3-dienyl)-benzene in our laboratory. The geometry compares well with other related structures (Li et al., 2009; Wu et al., 2011). In the title compound, the cyclohexyl ring adopts a chair conformation. The plane of the phenyl ring and the least-squares plane of the cyclohexyl moiety enclose an angle of 69.80 (3)°, while the plane through the nitro group and the adjacent C17 atom encloses an angle of 87.12 (3)° with the phenyl ring. The Br1—C9—C10—C11 torsion angle of 175.8 (4)° confirms the E configuration of the molecule with respect to the C9=C10 double bond. The molecules are linked by weak intermolecular N—O···Br interactions, the O···Br distance being 3.136 (4) Å.

For related compounds, see: Li et al. (2009); Wu et al. (2011). For the asymmetric Michael reaction, which allows for the formation of three contiguous asymmetric centers, see: Agarwal & Peddinti (2011); Lu et al. (2010); Luo et al. (2007).

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, with displacement ellipsoids for non-H atoms at the 40% probability level.
[Figure 2] Fig. 2. Unit cell packing of the title compound.
(2S,4S)-2-[(S,E)-2-Bromo-1-nitromethyl- 3-phenylallyl]-4-methylcyclohexanone top
Crystal data top
C17H20BrNO3F(000) = 752
Mr = 366.25Dx = 1.436 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 8068 reflections
a = 7.0942 (5) Åθ = 3.1–27.4°
b = 13.7920 (11) ŵ = 2.44 mm1
c = 17.3108 (13) ÅT = 296 K
V = 1693.7 (2) Å3Chunk, colourless
Z = 40.40 × 0.38 × 0.30 mm
Data collection top
Rigaku R-AXIS RAPID/ZJUG
diffractometer
3829 independent reflections
Radiation source: rotating anode1967 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.092
Detector resolution: 10.00 pixels mm-1θmax = 27.4°, θmin = 3.1°
ω scansh = 97
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
k = 1717
Tmin = 0.377, Tmax = 0.481l = 2221
13310 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.040H-atom parameters constrained
wR(F2) = 0.106 w = 1/[σ2(Fo2) + (0.030P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.91(Δ/σ)max = 0.001
3829 reflectionsΔρmax = 0.29 e Å3
200 parametersΔρmin = 0.35 e Å3
0 restraintsAbsolute structure: Flack (1983), 1625 Friedel pairs
0 constraintsAbsolute structure parameter: 0.019 (14)
Primary atom site location: structure-invariant direct methods
Crystal data top
C17H20BrNO3V = 1693.7 (2) Å3
Mr = 366.25Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 7.0942 (5) ŵ = 2.44 mm1
b = 13.7920 (11) ÅT = 296 K
c = 17.3108 (13) Å0.40 × 0.38 × 0.30 mm
Data collection top
Rigaku R-AXIS RAPID/ZJUG
diffractometer
3829 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
1967 reflections with I > 2σ(I)
Tmin = 0.377, Tmax = 0.481Rint = 0.092
13310 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.040H-atom parameters constrained
wR(F2) = 0.106Δρmax = 0.29 e Å3
S = 0.91Δρmin = 0.35 e Å3
3829 reflectionsAbsolute structure: Flack (1983), 1625 Friedel pairs
200 parametersAbsolute structure parameter: 0.019 (14)
0 restraints
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Br11.02011 (8)0.36551 (3)0.51179 (3)0.0761 (2)
O10.4791 (5)0.6330 (2)0.46539 (18)0.0755 (8)
O20.5698 (8)0.3042 (3)0.6070 (2)0.1185 (17)
O30.4316 (6)0.4334 (4)0.6423 (2)0.1077 (15)
N10.5198 (7)0.3865 (3)0.5965 (2)0.0757 (12)
C20.7862 (6)0.5611 (3)0.4626 (2)0.0501 (11)
H20.81730.51160.42400.060*
C10.7353 (6)0.5087 (3)0.5385 (2)0.0483 (11)
H10.68650.55760.57440.058*
C30.6255 (7)0.6214 (3)0.4309 (2)0.0579 (12)
C40.6690 (7)0.6733 (4)0.3565 (3)0.0762 (15)
H4A0.56330.71410.34220.091*
H4B0.68800.62610.31560.091*
C50.8469 (8)0.7357 (4)0.3653 (3)0.0817 (17)
H5A0.88060.76240.31540.098*
H5B0.81970.78940.39970.098*
C61.0146 (7)0.6786 (3)0.3972 (2)0.0627 (11)
H61.11280.72590.41010.075*
C70.9604 (6)0.6279 (3)0.4720 (2)0.0565 (10)
H7A0.93350.67640.51110.068*
H7B1.06630.58960.48990.068*
C81.0995 (8)0.6087 (4)0.3388 (3)0.0883 (18)
H8A1.20330.57480.36200.132*
H8B1.14350.64430.29470.132*
H8C1.00550.56290.32280.132*
C90.9023 (7)0.4616 (3)0.5761 (2)0.0563 (12)
C100.9783 (7)0.4757 (3)0.6453 (2)0.0599 (11)
H101.07730.43430.65760.072*
C110.9294 (7)0.5474 (3)0.7059 (2)0.0537 (12)
C120.7487 (7)0.5782 (4)0.7244 (2)0.0666 (14)
H120.64650.55300.69740.080*
C130.7176 (8)0.6451 (4)0.7817 (3)0.0798 (16)
H130.59540.66540.79250.096*
C140.8649 (10)0.6819 (4)0.8232 (3)0.0842 (18)
H140.84320.72770.86160.101*
C151.0436 (9)0.6515 (4)0.8081 (3)0.0895 (18)
H151.14430.67620.83630.107*
C161.0753 (7)0.5830 (4)0.7500 (2)0.0720 (14)
H161.19730.56110.74100.086*
C170.5758 (6)0.4353 (3)0.5233 (2)0.0625 (12)
H17A0.46790.46860.50140.075*
H17B0.61820.38710.48630.075*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.1030 (4)0.0633 (3)0.0619 (3)0.0246 (3)0.0012 (3)0.0079 (2)
O10.067 (2)0.076 (2)0.083 (2)0.016 (2)0.0017 (18)0.0001 (17)
O20.175 (5)0.079 (3)0.101 (3)0.029 (3)0.004 (3)0.017 (2)
O30.105 (3)0.132 (4)0.086 (2)0.027 (3)0.031 (2)0.021 (3)
N10.083 (3)0.078 (3)0.066 (2)0.029 (3)0.000 (3)0.005 (2)
C20.060 (3)0.041 (3)0.049 (2)0.001 (2)0.001 (2)0.0039 (19)
C10.052 (3)0.044 (3)0.049 (2)0.002 (2)0.006 (2)0.0027 (19)
C30.057 (3)0.058 (3)0.059 (3)0.003 (3)0.014 (2)0.002 (2)
C40.084 (4)0.078 (4)0.067 (3)0.004 (3)0.016 (3)0.017 (3)
C50.089 (4)0.077 (4)0.079 (3)0.003 (3)0.001 (3)0.022 (3)
C60.070 (3)0.059 (3)0.059 (2)0.010 (3)0.002 (3)0.003 (2)
C70.054 (3)0.060 (3)0.056 (2)0.004 (2)0.002 (2)0.002 (2)
C80.092 (4)0.105 (5)0.068 (3)0.014 (3)0.010 (3)0.001 (3)
C90.066 (3)0.052 (3)0.051 (2)0.007 (2)0.002 (2)0.001 (2)
C100.067 (3)0.056 (3)0.056 (2)0.012 (3)0.005 (3)0.0023 (19)
C110.065 (3)0.054 (3)0.042 (2)0.001 (2)0.010 (2)0.0020 (19)
C120.066 (4)0.088 (4)0.047 (3)0.002 (3)0.003 (2)0.008 (2)
C130.103 (4)0.084 (4)0.052 (3)0.017 (4)0.001 (3)0.011 (3)
C140.140 (6)0.061 (4)0.052 (3)0.000 (4)0.001 (4)0.008 (3)
C150.116 (6)0.089 (4)0.064 (3)0.026 (4)0.016 (3)0.014 (3)
C160.073 (4)0.082 (4)0.061 (3)0.004 (3)0.005 (3)0.003 (3)
C170.073 (3)0.063 (3)0.051 (2)0.020 (2)0.005 (2)0.002 (2)
Geometric parameters (Å, º) top
Br1—C91.923 (4)C7—H7A0.9700
O1—C31.208 (5)C7—H7B0.9700
O2—N11.203 (5)C8—H8A0.9600
O3—N11.199 (5)C8—H8B0.9600
N1—C171.490 (5)C8—H8C0.9600
C2—C31.514 (6)C9—C101.328 (5)
C2—C11.542 (5)C10—C111.483 (6)
C2—C71.551 (5)C10—H100.9300
C2—H20.9800C11—C161.377 (6)
C1—C91.500 (6)C11—C121.387 (6)
C1—C171.541 (6)C12—C131.374 (7)
C1—H10.9800C12—H120.9300
C3—C41.506 (6)C13—C141.365 (8)
C4—C51.535 (7)C13—H130.9300
C4—H4A0.9700C14—C151.361 (8)
C4—H4B0.9700C14—H140.9300
C5—C61.530 (6)C15—C161.397 (7)
C5—H5A0.9700C15—H150.9300
C5—H5B0.9700C16—H160.9300
C6—C81.521 (6)C17—H17A0.9700
C6—C71.520 (5)C17—H17B0.9700
C6—H60.9800
O3—N1—O2124.3 (5)C6—C7—H7B109.1
O3—N1—C17117.3 (5)C2—C7—H7B109.1
O2—N1—C17118.4 (5)H7A—C7—H7B107.8
C3—C2—C1112.9 (4)C6—C8—H8A109.5
C3—C2—C7108.1 (3)C6—C8—H8B109.5
C1—C2—C7112.0 (3)H8A—C8—H8B109.5
C3—C2—H2107.8C6—C8—H8C109.5
C1—C2—H2107.8H8A—C8—H8C109.5
C7—C2—H2107.8H8B—C8—H8C109.5
C9—C1—C17111.7 (4)C10—C9—C1130.5 (4)
C9—C1—C2112.9 (3)C10—C9—Br1116.5 (4)
C17—C1—C2109.5 (3)C1—C9—Br1113.0 (3)
C9—C1—H1107.5C9—C10—C11129.8 (4)
C17—C1—H1107.5C9—C10—H10115.1
C2—C1—H1107.5C11—C10—H10115.1
O1—C3—C4122.4 (4)C16—C11—C12117.2 (4)
O1—C3—C2122.7 (4)C16—C11—C10117.0 (4)
C4—C3—C2114.6 (4)C12—C11—C10125.7 (4)
C3—C4—C5110.4 (4)C13—C12—C11121.3 (5)
C3—C4—H4A109.6C13—C12—H12119.3
C5—C4—H4A109.6C11—C12—H12119.3
C3—C4—H4B109.6C14—C13—C12120.5 (5)
C5—C4—H4B109.6C14—C13—H13119.8
H4A—C4—H4B108.1C12—C13—H13119.8
C6—C5—C4112.7 (4)C15—C14—C13119.8 (5)
C6—C5—H5A109.0C15—C14—H14120.1
C4—C5—H5A109.0C13—C14—H14120.1
C6—C5—H5B109.0C14—C15—C16119.8 (5)
C4—C5—H5B109.0C14—C15—H15120.1
H5A—C5—H5B107.8C16—C15—H15120.1
C8—C6—C7112.1 (4)C11—C16—C15121.3 (5)
C8—C6—C5113.2 (4)C11—C16—H16119.4
C7—C6—C5110.3 (4)C15—C16—H16119.4
C8—C6—H6107.0N1—C17—C1110.3 (3)
C7—C6—H6107.0N1—C17—H17A109.6
C5—C6—H6107.0C1—C17—H17A109.6
C6—C7—C2112.7 (3)N1—C17—H17B109.6
C6—C7—H7A109.1C1—C17—H17B109.6
C2—C7—H7A109.1H17A—C17—H17B108.1
C3—C2—C1—C9171.2 (3)C17—C1—C9—Br163.8 (4)
C7—C2—C1—C948.7 (5)C2—C1—C9—Br160.0 (4)
C3—C2—C1—C1763.8 (5)C1—C9—C10—C114.4 (8)
C7—C2—C1—C17173.8 (3)Br1—C9—C10—C11175.8 (4)
C1—C2—C3—O15.7 (6)C9—C10—C11—C16146.0 (5)
C7—C2—C3—O1118.9 (5)C9—C10—C11—C1237.3 (8)
C1—C2—C3—C4179.6 (4)C16—C11—C12—C133.2 (7)
C7—C2—C3—C455.8 (5)C10—C11—C12—C13179.9 (5)
O1—C3—C4—C5120.0 (5)C11—C12—C13—C141.1 (9)
C2—C3—C4—C554.7 (6)C12—C13—C14—C150.7 (9)
C3—C4—C5—C652.3 (6)C13—C14—C15—C160.3 (9)
C4—C5—C6—C873.0 (5)C12—C11—C16—C153.6 (7)
C4—C5—C6—C753.5 (5)C10—C11—C16—C15179.4 (4)
C8—C6—C7—C271.2 (5)C14—C15—C16—C111.9 (8)
C5—C6—C7—C255.9 (5)O3—N1—C17—C173.0 (5)
C3—C2—C7—C656.0 (4)O2—N1—C17—C1104.9 (5)
C1—C2—C7—C6178.9 (4)C9—C1—C17—N156.4 (5)
C17—C1—C9—C10115.9 (5)C2—C1—C17—N1177.9 (4)
C2—C1—C9—C10120.2 (5)

Experimental details

Crystal data
Chemical formulaC17H20BrNO3
Mr366.25
Crystal system, space groupOrthorhombic, P212121
Temperature (K)296
a, b, c (Å)7.0942 (5), 13.7920 (11), 17.3108 (13)
V3)1693.7 (2)
Z4
Radiation typeMo Kα
µ (mm1)2.44
Crystal size (mm)0.40 × 0.38 × 0.30
Data collection
DiffractometerRigaku R-AXIS RAPID/ZJUG
Absorption correctionMulti-scan
(ABSCOR; Higashi, 1995)
Tmin, Tmax0.377, 0.481
No. of measured, independent and
observed [I > 2σ(I)] reflections
13310, 3829, 1967
Rint0.092
(sin θ/λ)max1)0.648
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.106, 0.91
No. of reflections3829
No. of parameters200
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.29, 0.35
Absolute structureFlack (1983), 1625 Friedel pairs
Absolute structure parameter0.019 (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).

 

Acknowledgements

We thank Professor Jian-Ming Gu of Zhejiang University for his help.

References

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