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

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(4aR,9R,9aR)-7-Bromo-9-nitro­methyl-2,3,4,4a,9,9a-hexa­hydro-1H-xanthen-1-one

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

(Received 19 February 2013; accepted 29 March 2013; online 27 April 2013)

The title compound, C14H14BrNO4, contains a tricyclic ring system including three contiguous stereocenters all of which exhibit an R configuration. The cyclo­hexa­none ring adopts a chair conformation. The central oxane ring assumes a strained envelope conformation, with five of the ring atoms being nearly coplanar with the bromo­phenyl group and with the C atom adjacent to the O atom and fused with the cyclo­hexa­none ring as the flap. In the crystal, mol­ecules are linked into a three-dimensional network by C—H⋯O inter­actions.

Related literature

For related structures, see: Shi et al. (2004[Shi, G.-F., Lu, R.-H., Yang, Y.-S., Li, C.-L., Yang, A.-M. & Cai, L.-X. (2004). Acta Cryst. E60, o878-o880.]); Xia et al. (2009[Xia, A.-B., Tang, J., Jiang, J.-R., Wang, Y.-F. & Luo, S.-P. (2009). Acta Cryst. E65, o2091.]); Ndjakou Lenta et al. (2007[Ndjakou Lenta, B., Devkota, K. P., Neumann, B., Tsamo, E. & Sewald, N. (2007). Acta Cryst. E63, o1629-o1631.]). For background information on domino reactions, see Enders et al. (2007[Enders, D., Grondal, C. & Huttl, M. R. M. (2007). Angew. Chem. Int. Ed. 46, 1570-1581.]); Yu & Wang (2002[Yu, X. & Wang, W. (2002). Org. Biomol. Chem. 6, 2037-2046.]).

[Scheme 1]

Experimental

Crystal data
  • C14H14BrNO4

  • Mr = 340.17

  • Monoclinic, P 21

  • a = 10.3457 (7) Å

  • b = 5.4662 (5) Å

  • c = 13.2446 (12) Å

  • β = 102.849 (2)°

  • V = 730.25 (11) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 2.83 mm−1

  • T = 296 K

  • 0.53 × 0.47 × 0.14 mm

Data collection
  • Rigaku R-AXIS RAPID diffractometer

  • Absorption correction: multi-scan (ABSCOR; Higashi, 1995[Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.224, Tmax = 0.673

  • 6335 measured reflections

  • 2655 independent reflections

  • 1537 reflections with I > 2σ(I)

  • Rint = 0.061

Refinement
  • R[F2 > 2σ(F2)] = 0.052

  • wR(F2) = 0.137

  • S = 1.00

  • 2655 reflections

  • 181 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.36 e Å−3

  • Δρmin = −0.46 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1058 Friedel pairs

  • Flack parameter: 0.021 (17)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C3—H3⋯O1i 0.93 2.71 3.520 (9) 146
C8—H8B⋯O2ii 0.97 2.59 3.489 (6) 155
C8—H8A⋯O4iii 0.97 2.54 3.253 (4) 131
C10—H10⋯O2iv 0.98 2.53 3.300 (8) 135
C11—H11⋯O3v 0.98 2.59 3.547 (8) 165
Symmetry codes: (i) [-x+1, y+{\script{1\over 2}}, -z+1]; (ii) [-x+1, y-{\script{1\over 2}}, -z]; (iii) [-x+1, y+{\script{1\over 2}}, -z]; (iv) x, y-1, z; (v) 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 Corporation, 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

Domino or cascade reactions, in which multiple new bonds and stereocenters could be formed, have been getting more interest in asymmetric organocatalysis (Enders et al., 2007; Yu et al., 2002) . The title compound, (I), was synthesized as one of a series of oxa-Michael-Michael products under investigation.

In this paper, the crystal of title compound (4aR,9R,9aR)-7-bromo-9- (nitromethyl)-2,3,4,4a,9,9a-hexahydro-1H-xanthen-1-one was determined. The structure of (I) is shown in Fig. 1. The O1—C4 bond and the bromophenyl group are almost coplanar: the angle is 3.2 (6) ° between the plane of the bromophenyl ring and the O1—C4—C12 plane. The C11—C12 bond and the bromophenyl plane enclose an angle of 9.4 (7) °. The cyclohexanone ring (C5—C6—C7—C8—C9—C10) adopts a chair conformation. The conformation of the oxane ring is nonstandard. Five atoms of the oxane ring are coplanar with the bromophenyl group and only C5 deviates significantly from the common plane.

Related literature top

For related structures, see: Shi et al. (2004); Xia et al. (2009); Ndjakou Lenta et al. (2007). For background information on domino reactions, see Enders et al. (2007); Yu & Wang (2002).

Experimental top

To the solution of the catalyst (S)-2-(pyrrolidin-2-ylmethylthio)pyridine (20 mol%) and 4-(trifluoromethyl)benzoic acid (10 mol%) in saturated aqueous NaCl (0.25 ml) was added sequentially cyclohexenone (0.8 mmol) and (E)-4-bromo-2-(2-nitrovinyl)phenol (0.2 mmol) at room temperature with vigorous stirring. After completion, the reaction mixture was extracted with EtOAc (3*10 ml), washed with water, dried and concentrated. The residue was purified by flash chromatography to the product. Then, suitable crystals of the title compound were obtained by slow evaporation of methanol solution at room temperature.

Refinement top

H atoms were placed in calculated position with C—H=0.98 Å(sp), C—H=0.97 Å(sp2), C—H=0.93 Å(aromatic). All H atoms were included in the final cycles of refinement as riding mode, 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, with the atomic labeling scheme. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. Unit cell packing of the title compound.
(4aR,9R,9aR)-7-Bromo-9-nitromethyl-2,3,4,4a,9,9a-hexahydro-1H-xanthen-1-one top
Crystal data top
C14H14BrNO4F(000) = 344
Mr = 340.17Dx = 1.547 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 4391 reflections
a = 10.3457 (7) Åθ = 3.2–27.4°
b = 5.4662 (5) ŵ = 2.83 mm1
c = 13.2446 (12) ÅT = 296 K
β = 102.849 (2)°Platelet, colorless
V = 730.25 (11) Å30.53 × 0.47 × 0.14 mm
Z = 2
Data collection top
Rigaku R-AXIS RAPID
diffractometer
2655 independent reflections
Radiation source: rotating anode1537 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.061
Detector resolution: 10.00 pixels mm-1θmax = 26.0°, θmin = 3.2°
ω scansh = 1212
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
k = 66
Tmin = 0.224, Tmax = 0.673l = 1616
6335 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)] = 0.052H-atom parameters constrained
wR(F2) = 0.137 w = 1/[σ2(Fo2) + (0.0525P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.00(Δ/σ)max < 0.001
2655 reflectionsΔρmax = 0.36 e Å3
181 parametersΔρmin = 0.46 e Å3
1 restraintAbsolute structure: Flack (1983), 1058 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.021 (17)
Crystal data top
C14H14BrNO4V = 730.25 (11) Å3
Mr = 340.17Z = 2
Monoclinic, P21Mo Kα radiation
a = 10.3457 (7) ŵ = 2.83 mm1
b = 5.4662 (5) ÅT = 296 K
c = 13.2446 (12) Å0.53 × 0.47 × 0.14 mm
β = 102.849 (2)°
Data collection top
Rigaku R-AXIS RAPID
diffractometer
2655 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
1537 reflections with I > 2σ(I)
Tmin = 0.224, Tmax = 0.673Rint = 0.061
6335 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.052H-atom parameters constrained
wR(F2) = 0.137Δρmax = 0.36 e Å3
S = 1.00Δρmin = 0.46 e Å3
2655 reflectionsAbsolute structure: Flack (1983), 1058 Friedel pairs
181 parametersAbsolute structure parameter: 0.021 (17)
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
C10.1121 (7)0.9599 (12)0.3568 (5)0.0740 (18)
C20.2242 (7)0.9776 (13)0.4388 (6)0.084 (2)
H20.22011.06580.49800.101*
C30.3408 (7)0.8631 (13)0.4308 (5)0.079 (2)
H30.41540.87570.48470.095*
C40.3469 (5)0.7291 (10)0.3426 (5)0.0575 (14)
C50.4665 (5)0.4397 (10)0.2629 (5)0.0594 (15)
H50.42120.29170.27850.071*
C60.6112 (5)0.3829 (12)0.2656 (6)0.074 (2)
H6A0.65350.32220.33370.089*
H6B0.61600.25550.21560.089*
C70.6840 (5)0.6043 (15)0.2415 (5)0.0816 (19)
H7A0.77410.55880.23970.098*
H7B0.68820.72440.29600.098*
C80.6170 (5)0.7183 (13)0.1378 (6)0.077 (2)
H8A0.65990.87220.12920.092*
H8B0.62730.61010.08200.092*
C90.4716 (5)0.7627 (10)0.1311 (4)0.0553 (14)
C100.3944 (4)0.5445 (8)0.1576 (4)0.0461 (12)
H100.39450.41830.10500.055*
C110.2504 (4)0.6049 (10)0.1573 (4)0.0487 (12)
H110.21960.72660.10290.058*
C120.2391 (5)0.7152 (9)0.2586 (5)0.0518 (14)
C130.1217 (6)0.8341 (11)0.2703 (5)0.0650 (16)
H130.04730.82550.21600.078*
C140.1623 (5)0.3767 (10)0.1314 (5)0.0572 (15)
H14A0.20380.24030.17320.069*
H14B0.07730.40730.14850.069*
N10.1410 (4)0.3111 (10)0.0188 (5)0.0621 (14)
O10.4667 (3)0.6210 (10)0.3413 (3)0.0647 (10)
O20.4213 (4)0.9576 (7)0.1075 (4)0.0745 (13)
O30.1104 (4)0.0988 (9)0.0041 (4)0.1026 (17)
O40.1497 (5)0.4689 (10)0.0439 (4)0.0874 (14)
Br10.04348 (7)1.1196 (2)0.36550 (7)0.1208 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.094 (4)0.080 (4)0.048 (5)0.010 (3)0.015 (4)0.003 (4)
C20.096 (5)0.101 (5)0.057 (5)0.017 (4)0.022 (4)0.021 (4)
C30.091 (5)0.100 (5)0.042 (4)0.014 (4)0.003 (3)0.012 (4)
C40.064 (3)0.065 (3)0.044 (4)0.008 (3)0.015 (3)0.007 (3)
C50.063 (3)0.065 (3)0.050 (4)0.008 (3)0.011 (3)0.009 (3)
C60.045 (3)0.093 (4)0.078 (5)0.008 (3)0.002 (3)0.024 (4)
C70.046 (3)0.098 (5)0.096 (5)0.001 (4)0.004 (3)0.019 (5)
C80.069 (4)0.080 (4)0.087 (6)0.000 (3)0.029 (4)0.008 (4)
C90.066 (3)0.061 (4)0.037 (4)0.004 (3)0.008 (3)0.005 (3)
C100.053 (2)0.047 (3)0.039 (3)0.000 (2)0.011 (2)0.009 (2)
C110.057 (2)0.044 (2)0.044 (3)0.002 (3)0.009 (2)0.005 (3)
C120.053 (3)0.054 (3)0.050 (4)0.003 (2)0.013 (2)0.006 (2)
C130.070 (3)0.066 (4)0.059 (5)0.001 (3)0.013 (3)0.010 (3)
C140.047 (3)0.056 (3)0.069 (5)0.006 (2)0.013 (3)0.001 (3)
N10.037 (2)0.072 (3)0.073 (4)0.011 (2)0.002 (2)0.010 (3)
O10.063 (2)0.086 (2)0.040 (2)0.016 (2)0.0012 (16)0.008 (2)
O20.084 (3)0.056 (2)0.083 (4)0.013 (2)0.017 (2)0.011 (2)
O30.097 (3)0.070 (3)0.123 (4)0.004 (3)0.015 (3)0.040 (3)
O40.104 (3)0.105 (4)0.052 (3)0.013 (3)0.013 (3)0.012 (3)
Br10.1011 (5)0.1479 (8)0.1168 (8)0.0504 (6)0.0314 (5)0.0231 (7)
Geometric parameters (Å, º) top
C1—C131.359 (9)C7—H7B0.9700
C1—C21.405 (9)C8—C91.506 (8)
C1—Br11.857 (6)C8—H8A0.9700
C2—C31.383 (8)C8—H8B0.9700
C2—H20.9300C9—O21.196 (6)
C3—C41.393 (8)C9—C101.519 (7)
C3—H30.9300C10—C111.525 (6)
C4—O11.376 (6)C10—H100.9800
C4—C121.391 (7)C11—C121.499 (7)
C5—O11.435 (8)C11—C141.538 (7)
C5—C61.521 (7)C11—H110.9800
C5—C101.538 (8)C12—C131.417 (7)
C5—H50.9800C13—H130.9300
C6—C71.497 (10)C14—N11.502 (8)
C6—H6A0.9700C14—H14A0.9700
C6—H6B0.9700C14—H14B0.9700
C7—C81.527 (9)N1—O41.214 (6)
C7—H7A0.9700N1—O31.223 (7)
C13—C1—C2119.0 (6)C7—C8—H8B109.3
C13—C1—Br1121.1 (5)H8A—C8—H8B108.0
C2—C1—Br1119.8 (5)O2—C9—C8122.0 (5)
C3—C2—C1119.6 (6)O2—C9—C10122.6 (5)
C3—C2—H2120.2C8—C9—C10115.4 (5)
C1—C2—H2120.2C9—C10—C11113.1 (4)
C2—C3—C4120.3 (6)C9—C10—C5109.1 (4)
C2—C3—H3119.8C11—C10—C5111.1 (4)
C4—C3—H3119.8C9—C10—H10107.8
O1—C4—C3116.4 (5)C11—C10—H10107.8
O1—C4—C12122.0 (5)C5—C10—H10107.8
C3—C4—C12121.5 (5)C12—C11—C10110.8 (4)
O1—C5—C6106.3 (5)C12—C11—C14111.4 (4)
O1—C5—C10108.8 (4)C10—C11—C14110.8 (4)
C6—C5—C10111.9 (5)C12—C11—H11107.9
O1—C5—H5109.9C10—C11—H11107.9
C6—C5—H5109.9C14—C11—H11107.9
C10—C5—H5109.9C4—C12—C13116.2 (5)
C7—C6—C5111.7 (5)C4—C12—C11122.0 (5)
C7—C6—H6A109.3C13—C12—C11121.5 (5)
C5—C6—H6A109.3C1—C13—C12123.3 (6)
C7—C6—H6B109.3C1—C13—H13118.3
C5—C6—H6B109.3C12—C13—H13118.3
H6A—C6—H6B107.9N1—C14—C11111.3 (5)
C6—C7—C8111.8 (5)N1—C14—H14A109.4
C6—C7—H7A109.2C11—C14—H14A109.4
C8—C7—H7A109.2N1—C14—H14B109.4
C6—C7—H7B109.2C11—C14—H14B109.4
C8—C7—H7B109.2H14A—C14—H14B108.0
H7A—C7—H7B107.9O4—N1—O3124.0 (6)
C9—C8—C7111.5 (6)O4—N1—C14119.5 (5)
C9—C8—H8A109.3O3—N1—C14116.4 (6)
C7—C8—H8A109.3C4—O1—C5116.7 (4)
C9—C8—H8B109.3
C13—C1—C2—C31.3 (11)C5—C10—C11—C1484.5 (5)
Br1—C1—C2—C3178.5 (6)O1—C4—C12—C13179.8 (5)
C1—C2—C3—C40.6 (11)C3—C4—C12—C133.2 (9)
C2—C3—C4—O1179.9 (6)O1—C4—C12—C116.6 (8)
C2—C3—C4—C122.9 (11)C3—C4—C12—C11170.4 (6)
O1—C5—C6—C761.4 (7)C10—C11—C12—C46.8 (7)
C10—C5—C6—C757.2 (7)C14—C11—C12—C4117.0 (5)
C5—C6—C7—C855.4 (7)C10—C11—C12—C13166.4 (4)
C6—C7—C8—C951.6 (7)C14—C11—C12—C1369.8 (6)
C7—C8—C9—O2128.3 (7)C2—C1—C13—C121.0 (10)
C7—C8—C9—C1051.1 (7)Br1—C1—C13—C12178.1 (4)
O2—C9—C10—C113.6 (8)C4—C12—C13—C11.2 (9)
C8—C9—C10—C11175.8 (5)C11—C12—C13—C1172.4 (6)
O2—C9—C10—C5127.8 (6)C12—C11—C14—N1162.8 (4)
C8—C9—C10—C551.6 (6)C10—C11—C14—N173.3 (5)
O1—C5—C10—C963.7 (5)C11—C14—N1—O425.2 (6)
C6—C5—C10—C953.5 (6)C11—C14—N1—O3157.5 (4)
O1—C5—C10—C1161.7 (5)C3—C4—O1—C5166.4 (6)
C6—C5—C10—C11178.9 (5)C12—C4—O1—C516.5 (8)
C9—C10—C11—C1283.4 (6)C6—C5—O1—C4170.2 (5)
C5—C10—C11—C1239.7 (6)C10—C5—O1—C449.5 (7)
C9—C10—C11—C14152.4 (5)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···O1i0.932.713.520 (9)146
C8—H8B···O2ii0.972.593.489 (6)155
C8—H8A···O4iii0.972.543.253 (4)131
C10—H10···O2iv0.982.533.300 (8)135
C11—H11···O3v0.982.593.547 (8)165
Symmetry codes: (i) x+1, y+1/2, z+1; (ii) x+1, y1/2, z; (iii) x+1, y+1/2, z; (iv) x, y1, z; (v) x, y+1, z.

Experimental details

Crystal data
Chemical formulaC14H14BrNO4
Mr340.17
Crystal system, space groupMonoclinic, P21
Temperature (K)296
a, b, c (Å)10.3457 (7), 5.4662 (5), 13.2446 (12)
β (°) 102.849 (2)
V3)730.25 (11)
Z2
Radiation typeMo Kα
µ (mm1)2.83
Crystal size (mm)0.53 × 0.47 × 0.14
Data collection
DiffractometerRigaku R-AXIS RAPID
diffractometer
Absorption correctionMulti-scan
(ABSCOR; Higashi, 1995)
Tmin, Tmax0.224, 0.673
No. of measured, independent and
observed [I > 2σ(I)] reflections
6335, 2655, 1537
Rint0.061
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.052, 0.137, 1.00
No. of reflections2655
No. of parameters181
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.36, 0.46
Absolute structureFlack (1983), 1058 Friedel pairs
Absolute structure parameter0.021 (17)

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
C3—H3···O1i0.9302.7103.520 (9)146
C8—H8B···O2ii0.9712.5863.489 (6)155
C8—H8A···O4iii0.9702.5353.253 (4)131
C10—H10···O2iv0.9812.5333.300 (8)135
C11—H11···O3v0.9802.5913.547 (8)165
Symmetry codes: (i) x+1, y+1/2, z+1; (ii) x+1, y1/2, z; (iii) x+1, y+1/2, z; (iv) x, y1, z; (v) x, y+1, z.
 

Acknowledgements

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

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