(S)-2-[(S,Z)-3-Bromo-1-nitro-4-phenyl­but-3-en-2-yl]cyclo­hexa­none

Wu, C.; Zhao, L.; Xia, A.-B.

doi:10.1107/S1600536811025633

organic compounds

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ISSN: 2056-9890

Volume 67| Part 8| August 2011| Page o1939

doi:10.1107/S1600536811025633

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(S)-2-[(S,Z)-3-Bromo-1-nitro-4-phenylbut-3-en-2-yl]cyclohexanone

Chao Wu,^a Long Zhao ^a and Ai-Bao Xia ^a ^*

^aState Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China
^*Correspondence e-mail: xiaaibao1983@163.com

(Received 27 June 2011; accepted 29 June 2011; online 6 July 2011)

In the crystal structure of the title compound, C₁₆H₁₈BrNO₃, the two stereogenic centres both have an S configuration. The cyclohexyl ring adopts a chair conformation. In the crystal, molecules are linked by weak N—O⋯Br contacts [O⋯Br = 3.289 (4) Å].

Related literature

For related structures, see: Li et al. (2010 ); Chua et al. (2009 ). For the asymmetric Michael reaction, which in principle allows for the formation of two contiguous asymmetric centers, see: Zeng & Zhong (2009 ); Roca-Lopez et al. (2010 ); Tsogoeva (2007 ); Sulzer-Mosse & Alexakis (2007 ); Mukherjee et al. (2007 ).

Experimental

Crystal data

C₁₆H₁₈BrNO₃
M_r = 352.22
Orthorhombic, P 2₁ 2₁ 2₁
a = 8.0091 (3) Å
b = 12.2395 (6) Å
c = 16.3039 (7) Å
V = 1598.23 (12) Å³
Z = 4
Mo Kα radiation
μ = 2.58 mm⁻¹
T = 296 K
0.33 × 0.29 × 0.25 mm

Data collection

Rigaku R-AXIS RAPID/ZJUG diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ) T_min = 0.428, T_max = 0.525
15575 measured reflections
3636 independent reflections
2369 reflections with I > 2σ(I)
R_int = 0.051

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.114
S = 1.00
3636 reflections
191 parameters
H-atom parameters constrained
Δρ_max = 0.82 e Å⁻³
Δρ_min = −1.05 e Å⁻³
Absolute structure: Flack (1983 ), 1548 Friedel pairs
Flack parameter: −0.018 (17)

Data collection: PROCESS-AUTO (Rigaku, 2006 ); cell refinement: PROCESS-AUTO; 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 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811025633/bt5566sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811025633/bt5566Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811025633/bt5566Isup3.cml

checkCIF report

Comment top

Nitroalkenes are important reagents in organic chemistry and they are the most prominent Michael acceptors used in organocatalytic reactions (Tsogoeva et al., 2007; Sulzer-Mosse et al., 2007; Mukherjee et al., 2007). Consequently, the title compound was synthesized as one of a series of solvent-free Michael products under investigation. In this paper, its absolute configuration and crystal structure are presented.The title compound is shown in Fig. 1. The cyclohexyl ring adopts a chair conformation. The plane of the phenyl ring and the least-square plane of the cyclohexyl moiety enclose an angle of 63.96 (3)°. The torsion angle O1—C7—Br1—C9 is 139.74 (2)° The molecules are linked by weak N1—O2···Br1 contacts. The O···Br distance is 3.289 Å.

Related literature top

For related structures, see: Li et al. (2010); Chua et al. (2009). For the asymmetric Michael reaction, which in principle allows for the formation of two contiguous asymmetric centers, see: Zeng & Zhong (2009); Roca-Lopez et al. (2010); Tsogoeva (2007); Sulzer-Mosse & Alexakis (2007); Mukherjee et al. (2007).

Experimental top

A mixture of (2-bromo-4-nitrobuta-1,3-dienyl)benzene (1 mmol) and cyclohexanone (8 mmol) in the presence of (S)-2-(pyrrolidin-2-ylmethylthio)pyridine(0.2 mmol) as amine catalyst and 4-(trifluoromethyl)benzoic acid(0.2 mmol) as cocatalyst at room temperature with stirring. After completion of the reaction, the mixture was extracted with ethyl acetate. The solvent was removed under reduced pressure and the residue was purified by silica gel column chromatography (eluent: petroleum ether-aether). Suitable crystals were obtained by slow evaporation of an ethyl ether solution.

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

	Fig. 1. The asymmetric unit of the structure of the title compound, with the atomic labeling scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. Unit cell packing of the title compound.

(S)-2-[(S,Z)-3-Bromo-1-nitro-4-phenylbut-3-en- 2-yl]cyclohexanone top

Crystal data top

C₁₆H₁₈BrNO₃	F(000) = 720
M_r = 352.22	D_x = 1.464 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 10471 reflections
a = 8.0091 (3) Å	θ = 3.0–27.4°
b = 12.2395 (6) Å	µ = 2.58 mm⁻¹
c = 16.3039 (7) Å	T = 296 K
V = 1598.23 (12) Å³	Chunk, colorless
Z = 4	0.33 × 0.29 × 0.25 mm

Data collection top

Rigaku R-AXIS RAPID/ZJUG diffractometer	3636 independent reflections
Radiation source: rolling anode	2369 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.051
Detector resolution: 10.00 pixels mm^-1	θ_max = 27.4°, θ_min = 3.0°
ω scans	h = −10→10
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	k = −15→15
T_min = 0.428, T_max = 0.525	l = −20→21
15575 measured reflections

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.037	w = 1/[σ²(F_o²) + (0.P)² + 4.1524P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.114	(Δ/σ)_max = 0.001
S = 1.00	Δρ_max = 0.82 e Å⁻³
3636 reflections	Δρ_min = −1.05 e Å⁻³
191 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0310 (13)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 1548 Friedel pairs
Secondary atom site location: difference Fourier map	Absolute structure parameter: −0.018 (17)

Crystal data top

C₁₆H₁₈BrNO₃	V = 1598.23 (12) Å³
M_r = 352.22	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 8.0091 (3) Å	µ = 2.58 mm⁻¹
b = 12.2395 (6) Å	T = 296 K
c = 16.3039 (7) Å	0.33 × 0.29 × 0.25 mm

Data collection top

Rigaku R-AXIS RAPID/ZJUG diffractometer	3636 independent reflections
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	2369 reflections with I > 2σ(I)
T_min = 0.428, T_max = 0.525	R_int = 0.051
15575 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	H-atom parameters constrained
wR(F²) = 0.114	Δρ_max = 0.82 e Å⁻³
S = 1.00	Δρ_min = −1.05 e Å⁻³
3636 reflections	Absolute structure: Flack (1983), 1548 Friedel pairs
191 parameters	Absolute structure parameter: −0.018 (17)
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

	x	y	z	U_iso*/U_eq
Br1	0.63058 (7)	0.46482 (5)	0.55564 (4)	0.0619 (2)
N1	0.1663 (6)	0.3677 (4)	0.5794 (3)	0.0571 (13)
O2	0.0229 (5)	0.3856 (5)	0.5610 (4)	0.0905 (15)
O1	0.1693 (7)	0.3171 (5)	0.3392 (3)	0.0885 (16)
C11	0.4279 (6)	0.7079 (4)	0.5742 (3)	0.0460 (13)
C2	0.4282 (7)	0.3931 (5)	0.3846 (3)	0.0495 (13)
H2	0.5210	0.3467	0.4025	0.059*
C1	0.3329 (6)	0.4313 (4)	0.4610 (3)	0.0466 (13)
H1	0.2289	0.4650	0.4420	0.056*
C10	0.3654 (7)	0.6156 (4)	0.5251 (3)	0.0462 (12)
H10	0.2658	0.6305	0.4979	0.055*
O3	0.2193 (7)	0.3763 (5)	0.6486 (3)	0.0933 (17)
C15	0.4339 (8)	0.9025 (5)	0.5950 (4)	0.0655 (18)
H15	0.4060	0.9722	0.5771	0.079*
C16	0.3855 (7)	0.8127 (4)	0.5505 (4)	0.0536 (12)
H16	0.3225	0.8227	0.5031	0.064*
C14	0.5235 (8)	0.8893 (6)	0.6660 (4)	0.0655 (18)
H14	0.5559	0.9500	0.6964	0.079*
C3	0.5005 (8)	0.4881 (5)	0.3337 (4)	0.0604 (16)
H3A	0.4103	0.5348	0.3152	0.073*
H3B	0.5743	0.5314	0.3678	0.073*
C9	0.4228 (6)	0.5152 (4)	0.5117 (3)	0.0460 (12)
C7	0.3176 (9)	0.3261 (5)	0.3272 (4)	0.0614 (17)
C12	0.5181 (8)	0.6956 (5)	0.6466 (4)	0.0606 (16)
H12	0.5470	0.6260	0.6647	0.073*
C8	0.2845 (8)	0.3328 (5)	0.5139 (4)	0.0559 (15)
H8A	0.2324	0.2774	0.4799	0.067*
H8B	0.3837	0.3014	0.5386	0.067*
C6	0.4045 (10)	0.2823 (6)	0.2531 (4)	0.078 (2)
H6A	0.3246	0.2449	0.2183	0.093*
H6B	0.4887	0.2298	0.2698	0.093*
C4	0.5965 (9)	0.4456 (6)	0.2599 (4)	0.079 (2)
H4A	0.6393	0.5069	0.2286	0.094*
H4B	0.6911	0.4028	0.2787	0.094*
C13	0.5651 (9)	0.7863 (6)	0.6919 (4)	0.0696 (19)
H13	0.6254	0.7772	0.7402	0.084*
C5	0.4875 (11)	0.3752 (7)	0.2046 (4)	0.089 (3)
H5A	0.5553	0.3445	0.1611	0.107*
H5B	0.4019	0.4204	0.1797	0.107*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0516 (3)	0.0585 (3)	0.0756 (4)	0.0081 (3)	−0.0139 (3)	−0.0041 (3)
N1	0.055 (3)	0.056 (3)	0.060 (3)	−0.008 (2)	0.007 (2)	0.013 (2)
O2	0.052 (3)	0.117 (4)	0.102 (4)	0.005 (3)	0.001 (3)	0.006 (4)
O1	0.084 (4)	0.101 (4)	0.080 (3)	−0.019 (3)	−0.015 (3)	−0.023 (3)
C11	0.046 (3)	0.047 (3)	0.045 (3)	−0.001 (2)	0.002 (2)	0.000 (2)
C2	0.053 (3)	0.050 (3)	0.046 (3)	0.005 (3)	−0.004 (2)	−0.004 (2)
C1	0.049 (3)	0.040 (3)	0.052 (3)	−0.002 (2)	−0.004 (2)	0.001 (2)
C10	0.044 (3)	0.048 (3)	0.046 (3)	0.002 (3)	−0.002 (3)	−0.002 (2)
O3	0.098 (4)	0.127 (5)	0.055 (3)	0.012 (3)	−0.002 (3)	0.010 (3)
C15	0.064 (4)	0.043 (3)	0.089 (5)	−0.001 (3)	0.006 (3)	−0.010 (3)
C16	0.053 (3)	0.042 (3)	0.066 (3)	0.006 (3)	−0.001 (3)	−0.001 (3)
C14	0.058 (4)	0.060 (4)	0.078 (5)	−0.012 (3)	0.007 (3)	−0.023 (4)
C3	0.064 (4)	0.057 (4)	0.061 (3)	0.000 (3)	0.008 (3)	0.009 (3)
C9	0.046 (3)	0.043 (3)	0.049 (3)	−0.001 (2)	0.000 (2)	0.002 (2)
C7	0.073 (4)	0.057 (4)	0.054 (4)	0.006 (3)	−0.008 (3)	−0.001 (3)
C12	0.076 (4)	0.050 (4)	0.055 (4)	0.006 (3)	−0.009 (3)	−0.008 (3)
C8	0.063 (4)	0.043 (3)	0.061 (4)	−0.003 (3)	0.005 (3)	−0.001 (3)
C6	0.100 (6)	0.073 (5)	0.060 (4)	0.021 (4)	−0.023 (4)	−0.018 (4)
C4	0.093 (5)	0.087 (5)	0.056 (4)	0.003 (5)	0.015 (4)	0.000 (4)
C13	0.082 (5)	0.065 (4)	0.062 (4)	0.000 (4)	−0.012 (3)	−0.018 (3)
C5	0.123 (7)	0.087 (6)	0.057 (4)	0.024 (5)	0.006 (4)	−0.005 (4)

Geometric parameters (Å, º) top

Br1—C9	1.914 (5)	C16—H16	0.9300
N1—O2	1.208 (6)	C14—C13	1.371 (9)
N1—O3	1.209 (6)	C14—H14	0.9300
N1—C8	1.490 (7)	C3—C4	1.520 (8)
O1—C7	1.209 (8)	C3—H3A	0.9700
C11—C16	1.382 (7)	C3—H3B	0.9700
C11—C12	1.393 (8)	C7—C6	1.493 (9)
C11—C10	1.472 (7)	C12—C13	1.385 (8)
C2—C7	1.528 (8)	C12—H12	0.9300
C2—C1	1.535 (7)	C8—H8A	0.9700
C2—C3	1.542 (8)	C8—H8B	0.9700
C2—H2	0.9800	C6—C5	1.536 (9)
C1—C9	1.502 (7)	C6—H6A	0.9700
C1—C8	1.532 (7)	C6—H6B	0.9700
C1—H1	0.9800	C4—C5	1.521 (9)
C10—C9	1.330 (7)	C4—H4A	0.9700
C10—H10	0.9300	C4—H4B	0.9700
C15—C14	1.371 (9)	C13—H13	0.9300
C15—C16	1.373 (8)	C5—H5A	0.9700
C15—H15	0.9300	C5—H5B	0.9700

O2—N1—O3	123.4 (6)	C10—C9—C1	123.8 (5)
O2—N1—C8	118.5 (6)	C10—C9—Br1	122.5 (4)
O3—N1—C8	118.1 (5)	C1—C9—Br1	113.7 (4)
C16—C11—C12	117.7 (5)	O1—C7—C6	123.8 (6)
C16—C11—C10	118.4 (5)	O1—C7—C2	121.3 (6)
C12—C11—C10	123.7 (5)	C6—C7—C2	114.7 (6)
C7—C2—C1	111.9 (5)	C13—C12—C11	120.4 (6)
C7—C2—C3	107.0 (5)	C13—C12—H12	119.8
C1—C2—C3	113.2 (5)	C11—C12—H12	119.8
C7—C2—H2	108.2	N1—C8—C1	109.8 (5)
C1—C2—H2	108.2	N1—C8—H8A	109.7
C3—C2—H2	108.2	C1—C8—H8A	109.7
C9—C1—C8	110.5 (4)	N1—C8—H8B	109.7
C9—C1—C2	114.6 (4)	C1—C8—H8B	109.7
C8—C1—C2	110.0 (4)	H8A—C8—H8B	108.2
C9—C1—H1	107.1	C7—C6—C5	110.6 (6)
C8—C1—H1	107.1	C7—C6—H6A	109.5
C2—C1—H1	107.1	C5—C6—H6A	109.5
C9—C10—C11	132.8 (5)	C7—C6—H6B	109.5
C9—C10—H10	113.6	C5—C6—H6B	109.5
C11—C10—H10	113.6	H6A—C6—H6B	108.1
C14—C15—C16	120.0 (6)	C5—C4—C3	111.8 (6)
C14—C15—H15	120.0	C5—C4—H4A	109.3
C16—C15—H15	120.0	C3—C4—H4A	109.3
C15—C16—C11	121.7 (6)	C5—C4—H4B	109.3
C15—C16—H16	119.2	C3—C4—H4B	109.3
C11—C16—H16	119.2	H4A—C4—H4B	107.9
C15—C14—C13	119.7 (6)	C14—C13—C12	120.5 (6)
C15—C14—H14	120.2	C14—C13—H13	119.8
C13—C14—H14	120.2	C12—C13—H13	119.8
C4—C3—C2	111.0 (5)	C4—C5—C6	111.3 (6)
C4—C3—H3A	109.4	C4—C5—H5A	109.4
C2—C3—H3A	109.4	C6—C5—H5A	109.4
C4—C3—H3B	109.4	C4—C5—H5B	109.4
C2—C3—H3B	109.4	C6—C5—H5B	109.4
H3A—C3—H3B	108.0	H5A—C5—H5B	108.0

C7—C2—C1—C9	−168.6 (5)	C1—C2—C7—O1	7.4 (9)
C3—C2—C1—C9	−47.6 (6)	C3—C2—C7—O1	−117.2 (7)
C7—C2—C1—C8	66.2 (6)	C1—C2—C7—C6	−177.6 (5)
C3—C2—C1—C8	−172.8 (5)	C3—C2—C7—C6	57.8 (7)
C16—C11—C10—C9	152.7 (6)	C16—C11—C12—C13	−1.0 (9)
C12—C11—C10—C9	−31.9 (9)	C10—C11—C12—C13	−176.5 (6)
C14—C15—C16—C11	−1.5 (9)	O2—N1—C8—C1	75.7 (7)
C12—C11—C16—C15	1.8 (9)	O3—N1—C8—C1	−104.4 (6)
C10—C11—C16—C15	177.5 (5)	C9—C1—C8—N1	62.7 (6)
C16—C15—C14—C13	0.4 (10)	C2—C1—C8—N1	−169.7 (5)
C7—C2—C3—C4	−57.4 (7)	O1—C7—C6—C5	119.3 (8)
C1—C2—C3—C4	178.8 (5)	C2—C7—C6—C5	−55.6 (8)
C11—C10—C9—C1	177.3 (5)	C2—C3—C4—C5	58.2 (8)
C11—C10—C9—Br1	−3.0 (9)	C15—C14—C13—C12	0.4 (10)
C8—C1—C9—C10	−116.9 (6)	C11—C12—C13—C14	0.0 (10)
C2—C1—C9—C10	118.1 (6)	C3—C4—C5—C6	−54.1 (8)
C8—C1—C9—Br1	63.3 (5)	C7—C6—C5—C4	51.6 (9)
C2—C1—C9—Br1	−61.7 (5)

Experimental details

Crystal data
Chemical formula	C₁₆H₁₈BrNO₃
M_r	352.22
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	296
a, b, c (Å)	8.0091 (3), 12.2395 (6), 16.3039 (7)
V (Å³)	1598.23 (12)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	2.58
Crystal size (mm)	0.33 × 0.29 × 0.25

Data collection
Diffractometer	Rigaku R-AXIS RAPID/ZJUG diffractometer
Absorption correction	Multi-scan (ABSCOR; Higashi, 1995)
T_min, T_max	0.428, 0.525
No. of measured, independent and observed [I > 2σ(I)] reflections	15575, 3636, 2369
R_int	0.051
(sin θ/λ)_max (Å⁻¹)	0.647

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.114, 1.00
No. of reflections	3636
No. of parameters	191
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.82, −1.05
Absolute structure	Flack (1983), 1548 Friedel pairs
Absolute structure parameter	−0.018 (17)

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

The authors thank Professor Jian-Ming Gu of Zhejiang University for his help. Wen-Zeng Weng and Chu-Xia Yan are thanked for their help with the synthesis.

References

Chua, P.-J., Tan, B., Zeng, X.-F. & Zhong, G.-F. (2009). Bioorg. Med. Chem. Lett. 19, 3915–3918. Web of Science CrossRef PubMed CAS Google Scholar
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