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

Zhao, L.; Wu, C.; Weng, W.-Z.; Yan, C.-X.; Xia, A.-B.

doi:10.1107/S1600536812013098

organic compounds

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ISSN: 2056-9890

Volume 68| Part 4| April 2012| Page o1253

doi:10.1107/S1600536812013098

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

Long Zhao,^a Chao Wu,^a Wen-Zeng Weng,^b Chu-Xia Yan ^b 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, 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 ); 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

Crystal data

C₁₇H₂₀BrNO₃
M_r = 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 ) T_min = 0.377, T_max = 0.481
13310 measured reflections
3829 independent reflections
1967 reflections with I > 2σ(I)
R_int = 0.092

Refinement

R[F² > 2σ(F²)] = 0.040
wR(F²) = 0.106
S = 0.91
3829 reflections
200 parameters
H-atom parameters constrained
Δρ_max = 0.29 e Å⁻³
Δρ_min = −0.35 e Å⁻³
Absolute structure: Flack (1983 ), 1625 Friedel pairs
Flack parameter: −0.019 (14)

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/S1600536812013098/bh2424sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812013098/bh2424Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812013098/bh2424Isup3.cml

checkCIF report

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.

Structure description 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).

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 displacement ellipsoids for non-H atoms at the 40% probability level.
	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

C₁₇H₂₀BrNO₃	F(000) = 752
M_r = 366.25	D_x = 1.436 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 8068 reflections
a = 7.0942 (5) Å	θ = 3.1–27.4°
b = 13.7920 (11) Å	µ = 2.44 mm⁻¹
c = 17.3108 (13) Å	T = 296 K
V = 1693.7 (2) Å³	Chunk, colourless
Z = 4	0.40 × 0.38 × 0.30 mm

Data collection top

Rigaku R-AXIS RAPID/ZJUG diffractometer	3829 independent reflections
Radiation source: rotating anode	1967 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.092
Detector resolution: 10.00 pixels mm^-1	θ_max = 27.4°, θ_min = 3.1°
ω scans	h = −9→7
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	k = −17→17
T_min = 0.377, T_max = 0.481	l = −22→21
13310 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.040	H-atom parameters constrained
wR(F²) = 0.106	w = 1/[σ²(F_o²) + (0.030P)²] where P = (F_o² + 2F_c²)/3
S = 0.91	(Δ/σ)_max = 0.001
3829 reflections	Δρ_max = 0.29 e Å⁻³
200 parameters	Δρ_min = −0.35 e Å⁻³
0 restraints	Absolute structure: Flack (1983), 1625 Friedel pairs
0 constraints	Absolute structure parameter: −0.019 (14)
Primary atom site location: structure-invariant direct methods

Crystal data top

C₁₇H₂₀BrNO₃	V = 1693.7 (2) Å³
M_r = 366.25	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 7.0942 (5) Å	µ = 2.44 mm⁻¹
b = 13.7920 (11) Å	T = 296 K
c = 17.3108 (13) Å	0.40 × 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)
T_min = 0.377, T_max = 0.481	R_int = 0.092
13310 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.040	H-atom parameters constrained
wR(F²) = 0.106	Δρ_max = 0.29 e Å⁻³
S = 0.91	Δρ_min = −0.35 e Å⁻³
3829 reflections	Absolute structure: Flack (1983), 1625 Friedel pairs
200 parameters	Absolute structure parameter: −0.019 (14)
0 restraints

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Br1	1.02011 (8)	0.36551 (3)	0.51179 (3)	0.0761 (2)
O1	0.4791 (5)	0.6330 (2)	0.46539 (18)	0.0755 (8)
O2	0.5698 (8)	0.3042 (3)	0.6070 (2)	0.1185 (17)
O3	0.4316 (6)	0.4334 (4)	0.6423 (2)	0.1077 (15)
N1	0.5198 (7)	0.3865 (3)	0.5965 (2)	0.0757 (12)
C2	0.7862 (6)	0.5611 (3)	0.4626 (2)	0.0501 (11)
H2	0.8173	0.5116	0.4240	0.060*
C1	0.7353 (6)	0.5087 (3)	0.5385 (2)	0.0483 (11)
H1	0.6865	0.5576	0.5744	0.058*
C3	0.6255 (7)	0.6214 (3)	0.4309 (2)	0.0579 (12)
C4	0.6690 (7)	0.6733 (4)	0.3565 (3)	0.0762 (15)
H4A	0.5633	0.7141	0.3422	0.091*
H4B	0.6880	0.6261	0.3156	0.091*
C5	0.8469 (8)	0.7357 (4)	0.3653 (3)	0.0817 (17)
H5A	0.8806	0.7624	0.3154	0.098*
H5B	0.8197	0.7894	0.3997	0.098*
C6	1.0146 (7)	0.6786 (3)	0.3972 (2)	0.0627 (11)
H6	1.1128	0.7259	0.4101	0.075*
C7	0.9604 (6)	0.6279 (3)	0.4720 (2)	0.0565 (10)
H7A	0.9335	0.6764	0.5111	0.068*
H7B	1.0663	0.5896	0.4899	0.068*
C8	1.0995 (8)	0.6087 (4)	0.3388 (3)	0.0883 (18)
H8A	1.2033	0.5748	0.3620	0.132*
H8B	1.1435	0.6443	0.2947	0.132*
H8C	1.0055	0.5629	0.3228	0.132*
C9	0.9023 (7)	0.4616 (3)	0.5761 (2)	0.0563 (12)
C10	0.9783 (7)	0.4757 (3)	0.6453 (2)	0.0599 (11)
H10	1.0773	0.4343	0.6576	0.072*
C11	0.9294 (7)	0.5474 (3)	0.7059 (2)	0.0537 (12)
C12	0.7487 (7)	0.5782 (4)	0.7244 (2)	0.0666 (14)
H12	0.6465	0.5530	0.6974	0.080*
C13	0.7176 (8)	0.6451 (4)	0.7817 (3)	0.0798 (16)
H13	0.5954	0.6654	0.7925	0.096*
C14	0.8649 (10)	0.6819 (4)	0.8232 (3)	0.0842 (18)
H14	0.8432	0.7277	0.8616	0.101*
C15	1.0436 (9)	0.6515 (4)	0.8081 (3)	0.0895 (18)
H15	1.1443	0.6762	0.8363	0.107*
C16	1.0753 (7)	0.5830 (4)	0.7500 (2)	0.0720 (14)
H16	1.1973	0.5611	0.7410	0.086*
C17	0.5758 (6)	0.4353 (3)	0.5233 (2)	0.0625 (12)
H17A	0.4679	0.4686	0.5014	0.075*
H17B	0.6182	0.3871	0.4863	0.075*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.1030 (4)	0.0633 (3)	0.0619 (3)	0.0246 (3)	−0.0012 (3)	−0.0079 (2)
O1	0.067 (2)	0.076 (2)	0.083 (2)	0.016 (2)	0.0017 (18)	−0.0001 (17)
O2	0.175 (5)	0.079 (3)	0.101 (3)	−0.029 (3)	0.004 (3)	0.017 (2)
O3	0.105 (3)	0.132 (4)	0.086 (2)	−0.027 (3)	0.031 (2)	−0.021 (3)
N1	0.083 (3)	0.078 (3)	0.066 (2)	−0.029 (3)	0.000 (3)	−0.005 (2)
C2	0.060 (3)	0.041 (3)	0.049 (2)	−0.001 (2)	−0.001 (2)	−0.0039 (19)
C1	0.052 (3)	0.044 (3)	0.049 (2)	−0.002 (2)	−0.006 (2)	−0.0027 (19)
C3	0.057 (3)	0.058 (3)	0.059 (3)	−0.003 (3)	−0.014 (2)	−0.002 (2)
C4	0.084 (4)	0.078 (4)	0.067 (3)	0.004 (3)	−0.016 (3)	0.017 (3)
C5	0.089 (4)	0.077 (4)	0.079 (3)	−0.003 (3)	−0.001 (3)	0.022 (3)
C6	0.070 (3)	0.059 (3)	0.059 (2)	−0.010 (3)	0.002 (3)	0.003 (2)
C7	0.054 (3)	0.060 (3)	0.056 (2)	−0.004 (2)	0.002 (2)	−0.002 (2)
C8	0.092 (4)	0.105 (5)	0.068 (3)	−0.014 (3)	0.010 (3)	0.001 (3)
C9	0.066 (3)	0.052 (3)	0.051 (2)	−0.007 (2)	0.002 (2)	−0.001 (2)
C10	0.067 (3)	0.056 (3)	0.056 (2)	0.012 (3)	−0.005 (3)	0.0023 (19)
C11	0.065 (3)	0.054 (3)	0.042 (2)	0.001 (2)	−0.010 (2)	0.0020 (19)
C12	0.066 (4)	0.088 (4)	0.047 (3)	0.002 (3)	−0.003 (2)	−0.008 (2)
C13	0.103 (4)	0.084 (4)	0.052 (3)	0.017 (4)	−0.001 (3)	−0.011 (3)
C14	0.140 (6)	0.061 (4)	0.052 (3)	0.000 (4)	−0.001 (4)	−0.008 (3)
C15	0.116 (6)	0.089 (4)	0.064 (3)	−0.026 (4)	−0.016 (3)	−0.014 (3)
C16	0.073 (4)	0.082 (4)	0.061 (3)	−0.004 (3)	−0.005 (3)	0.003 (3)
C17	0.073 (3)	0.063 (3)	0.051 (2)	−0.020 (2)	−0.005 (2)	0.002 (2)

Geometric parameters (Å, º) top

Br1—C9	1.923 (4)	C7—H7A	0.9700
O1—C3	1.208 (5)	C7—H7B	0.9700
O2—N1	1.203 (5)	C8—H8A	0.9600
O3—N1	1.199 (5)	C8—H8B	0.9600
N1—C17	1.490 (5)	C8—H8C	0.9600
C2—C3	1.514 (6)	C9—C10	1.328 (5)
C2—C1	1.542 (5)	C10—C11	1.483 (6)
C2—C7	1.551 (5)	C10—H10	0.9300
C2—H2	0.9800	C11—C16	1.377 (6)
C1—C9	1.500 (6)	C11—C12	1.387 (6)
C1—C17	1.541 (6)	C12—C13	1.374 (7)
C1—H1	0.9800	C12—H12	0.9300
C3—C4	1.506 (6)	C13—C14	1.365 (8)
C4—C5	1.535 (7)	C13—H13	0.9300
C4—H4A	0.9700	C14—C15	1.361 (8)
C4—H4B	0.9700	C14—H14	0.9300
C5—C6	1.530 (6)	C15—C16	1.397 (7)
C5—H5A	0.9700	C15—H15	0.9300
C5—H5B	0.9700	C16—H16	0.9300
C6—C8	1.521 (6)	C17—H17A	0.9700
C6—C7	1.520 (5)	C17—H17B	0.9700
C6—H6	0.9800

O3—N1—O2	124.3 (5)	C6—C7—H7B	109.1
O3—N1—C17	117.3 (5)	C2—C7—H7B	109.1
O2—N1—C17	118.4 (5)	H7A—C7—H7B	107.8
C3—C2—C1	112.9 (4)	C6—C8—H8A	109.5
C3—C2—C7	108.1 (3)	C6—C8—H8B	109.5
C1—C2—C7	112.0 (3)	H8A—C8—H8B	109.5
C3—C2—H2	107.8	C6—C8—H8C	109.5
C1—C2—H2	107.8	H8A—C8—H8C	109.5
C7—C2—H2	107.8	H8B—C8—H8C	109.5
C9—C1—C17	111.7 (4)	C10—C9—C1	130.5 (4)
C9—C1—C2	112.9 (3)	C10—C9—Br1	116.5 (4)
C17—C1—C2	109.5 (3)	C1—C9—Br1	113.0 (3)
C9—C1—H1	107.5	C9—C10—C11	129.8 (4)
C17—C1—H1	107.5	C9—C10—H10	115.1
C2—C1—H1	107.5	C11—C10—H10	115.1
O1—C3—C4	122.4 (4)	C16—C11—C12	117.2 (4)
O1—C3—C2	122.7 (4)	C16—C11—C10	117.0 (4)
C4—C3—C2	114.6 (4)	C12—C11—C10	125.7 (4)
C3—C4—C5	110.4 (4)	C13—C12—C11	121.3 (5)
C3—C4—H4A	109.6	C13—C12—H12	119.3
C5—C4—H4A	109.6	C11—C12—H12	119.3
C3—C4—H4B	109.6	C14—C13—C12	120.5 (5)
C5—C4—H4B	109.6	C14—C13—H13	119.8
H4A—C4—H4B	108.1	C12—C13—H13	119.8
C6—C5—C4	112.7 (4)	C15—C14—C13	119.8 (5)
C6—C5—H5A	109.0	C15—C14—H14	120.1
C4—C5—H5A	109.0	C13—C14—H14	120.1
C6—C5—H5B	109.0	C14—C15—C16	119.8 (5)
C4—C5—H5B	109.0	C14—C15—H15	120.1
H5A—C5—H5B	107.8	C16—C15—H15	120.1
C8—C6—C7	112.1 (4)	C11—C16—C15	121.3 (5)
C8—C6—C5	113.2 (4)	C11—C16—H16	119.4
C7—C6—C5	110.3 (4)	C15—C16—H16	119.4
C8—C6—H6	107.0	N1—C17—C1	110.3 (3)
C7—C6—H6	107.0	N1—C17—H17A	109.6
C5—C6—H6	107.0	C1—C17—H17A	109.6
C6—C7—C2	112.7 (3)	N1—C17—H17B	109.6
C6—C7—H7A	109.1	C1—C17—H17B	109.6
C2—C7—H7A	109.1	H17A—C17—H17B	108.1

C3—C2—C1—C9	−171.2 (3)	C17—C1—C9—Br1	63.8 (4)
C7—C2—C1—C9	−48.7 (5)	C2—C1—C9—Br1	−60.0 (4)
C3—C2—C1—C17	63.8 (5)	C1—C9—C10—C11	−4.4 (8)
C7—C2—C1—C17	−173.8 (3)	Br1—C9—C10—C11	175.8 (4)
C1—C2—C3—O1	5.7 (6)	C9—C10—C11—C16	−146.0 (5)
C7—C2—C3—O1	−118.9 (5)	C9—C10—C11—C12	37.3 (8)
C1—C2—C3—C4	−179.6 (4)	C16—C11—C12—C13	3.2 (7)
C7—C2—C3—C4	55.8 (5)	C10—C11—C12—C13	179.9 (5)
O1—C3—C4—C5	120.0 (5)	C11—C12—C13—C14	−1.1 (9)
C2—C3—C4—C5	−54.7 (6)	C12—C13—C14—C15	−0.7 (9)
C3—C4—C5—C6	52.3 (6)	C13—C14—C15—C16	0.3 (9)
C4—C5—C6—C8	73.0 (5)	C12—C11—C16—C15	−3.6 (7)
C4—C5—C6—C7	−53.5 (5)	C10—C11—C16—C15	179.4 (4)
C8—C6—C7—C2	−71.2 (5)	C14—C15—C16—C11	1.9 (8)
C5—C6—C7—C2	55.9 (5)	O3—N1—C17—C1	73.0 (5)
C3—C2—C7—C6	−56.0 (4)	O2—N1—C17—C1	−104.9 (5)
C1—C2—C7—C6	178.9 (4)	C9—C1—C17—N1	56.4 (5)
C17—C1—C9—C10	−115.9 (5)	C2—C1—C17—N1	−177.9 (4)
C2—C1—C9—C10	120.2 (5)

Experimental details

Crystal data
Chemical formula	C₁₇H₂₀BrNO₃
M_r	366.25
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	296
a, b, c (Å)	7.0942 (5), 13.7920 (11), 17.3108 (13)
V (Å³)	1693.7 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	2.44
Crystal size (mm)	0.40 × 0.38 × 0.30

Data collection
Diffractometer	Rigaku R-AXIS RAPID/ZJUG
Absorption correction	Multi-scan (ABSCOR; Higashi, 1995)
T_min, T_max	0.377, 0.481
No. of measured, independent and observed [I > 2σ(I)] reflections	13310, 3829, 1967
R_int	0.092
(sin θ/λ)_max (Å⁻¹)	0.648

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.040, 0.106, 0.91
No. of reflections	3829
No. of parameters	200
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.29, −0.35
Absolute structure	Flack (1983), 1625 Friedel pairs
Absolute structure parameter	−0.019 (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.

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