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

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(2S,3S)-3-(3-Bromo­phen­yl)-6,6-di­methyl-2-nitro-2,3,6,7-tetra­hydro­benzo­furan-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 18 June 2013; accepted 11 July 2013; online 17 July 2013)

The title compound, C16H16BrNO4, has two adjacent chiral C atoms and both have an S configuration. The fused cyclo­hex-2-enone and di­hydro­furan rings both adopt envelope conformations, with the quaternary C atom and the nitro-substituted C atoms as the respective flap. The flap atoms lie 0.607 (3) and −0.253 (2) Å, respectively, from the mean plane of the remaining ring atoms on opposite sides. The dihedral angle between the mean plane of the four coplanar atoms of the di­hydro­furan ring and the phenyl ring is 86.16 (3)°. In the crystal, mol­ecules are linked by weak C—H⋯O inter­actions, forming a ladder motif parallel to the b axis.

Related literature

For the occurrence of di­hydro­furans in nature and their synthetic applications, see: Fraga (1992[Fraga, B. M. (1992). Nat. Prod. Rep. 9, 217-241.]); Lipshutz (1986[Lipshutz, B. H. (1986). Chem. Rev. 86, 795-819.]). For synthetic procedures, 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.]).

[Scheme 1]

Experimental

Crystal data
  • C16H16BrNO4

  • Mr = 366.21

  • Orthorhombic, P 21 21 21

  • a = 6.6799 (7) Å

  • b = 7.3713 (9) Å

  • c = 32.9075 (14) Å

  • V = 1620.4 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 2.55 mm−1

  • T = 296 K

  • 0.38 × 0.36 × 0.31 mm

Data collection
  • Rigaku R-AXIS RAPID diffractometer

  • Absorption correction: multi-scan (ABSCOR; Higashi, 1995[Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.384, Tmax = 0.455

  • 13344 measured reflections

  • 2997 independent reflections

  • 1857 reflections with I > 2σ(I)

  • Rint = 0.066

Refinement
  • R[F2 > 2σ(F2)] = 0.051

  • wR(F2) = 0.108

  • S = 1.00

  • 2997 reflections

  • 200 parameters

  • H-atom parameters constrained

  • Δρmax = 0.51 e Å−3

  • Δρmin = −0.46 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1221 Friedel pairs

  • Absolute structure parameter: 0.003 (18)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C1—H1⋯O1i 0.98 2.29 3.165 (6) 148
C5—H5A⋯O2ii 0.97 2.66 3.351 (6) 129
C14—H14⋯O1iii 0.93 2.65 3.559 (7) 167
Symmetry codes: (i) x, y-1, z; (ii) x, y+1, z; (iii) [-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}].

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

Dihdrofurans are found in many naturally occurring compounds and are used as versatile intermediates in organic and natural product synthesis (Fraga, 1992; Lipshutz, 1986). Organocatalytic asymmetric domino reactions have received increasing attention in the synthetic community recently. The title compound, which was readily synthesized by the organocatalytic Michael-SN2 reaction of 5,5-dimethylcyclohexane-1,3-dione to (E)-1-bromo-3-(2-bromo-2-nitrovinyl)benzene (Fan et al., 2010; Rueping et al., 2010), could act as an intermediate in organic and natural product synthesis. In this article, the crystal structure of the title compoud (2S,3S)-3-(3-bromophenyl)-6,6-dimethyl-2- nitro-2,3,6,7-tetrahydrobenzofuran-4(5H)-one is described (Fig. 1).

Related literature top

For the occurrence of dihydrofurans in nature and their synthetic applications, see: Fraga (1992); Lipshutz (1986). For synthetic procedures, see: Fan et al. (2010); Rueping et al. (2010).

Experimental top

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

Methyl H atoms were placed in calculated positions with C—H = 0.96 (1) Å and the methyl torsion was refined to fit the electron density with Uiso(H) = 1.5Ueq(C). Other H atoms were placed in calculated positions with C—H = 0.98 (1) Å (CH), C—H = 0.97 (1) Å (CH2), 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(C).

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,3S)-3-(3-Bromophenyl)-6,6-dimethyl-2-nitro-2,3,6,7-tetrahydrobenzofuran-4(5H)-one top
Crystal data top
C16H16BrNO4F(000) = 744
Mr = 366.21Dx = 1.501 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 8549 reflections
a = 6.6799 (7) Åθ = 3.0–27.4°
b = 7.3713 (9) ŵ = 2.55 mm1
c = 32.9075 (14) ÅT = 296 K
V = 1620.4 (3) Å3Chunk, colourless
Z = 40.38 × 0.36 × 0.31 mm
Data collection top
Rigaku R-AXIS RAPID
diffractometer
2997 independent reflections
Radiation source: rotating anode1857 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.066
Detector resolution: 10.00 pixels mm-1θmax = 25.5°, θmin = 3.0°
ω scansh = 88
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
k = 88
Tmin = 0.384, Tmax = 0.455l = 3939
13344 measured reflections
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.051 w = 1/[σ2(Fo2) + (0.0122P)2 + 2.5684P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.108(Δ/σ)max < 0.001
S = 1.00Δρmax = 0.51 e Å3
2997 reflectionsΔρmin = 0.46 e Å3
200 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.0068 (8)
Primary atom site location: structure-invariant direct methodsAbsolute structure: Flack (1983), 1221 Friedel pairs
Secondary atom site location: difference Fourier mapAbsolute structure parameter: 0.003 (18)
Crystal data top
C16H16BrNO4V = 1620.4 (3) Å3
Mr = 366.21Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 6.6799 (7) ŵ = 2.55 mm1
b = 7.3713 (9) ÅT = 296 K
c = 32.9075 (14) Å0.38 × 0.36 × 0.31 mm
Data collection top
Rigaku R-AXIS RAPID
diffractometer
2997 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
1857 reflections with I > 2σ(I)
Tmin = 0.384, Tmax = 0.455Rint = 0.066
13344 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.051H-atom parameters constrained
wR(F2) = 0.108Δρmax = 0.51 e Å3
S = 1.00Δρmin = 0.46 e Å3
2997 reflectionsAbsolute structure: Flack (1983), 1221 Friedel pairs
200 parametersAbsolute structure parameter: 0.003 (18)
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
C10.7480 (8)0.0956 (7)0.38377 (16)0.0479 (13)
H10.72090.00910.36630.058*
C20.7540 (7)0.2708 (7)0.35851 (13)0.0445 (12)
H20.89230.31420.35640.053*
C30.6377 (8)0.3915 (6)0.38649 (13)0.0407 (12)
C40.6168 (8)0.5877 (7)0.38557 (14)0.0447 (12)
C50.5014 (8)0.6680 (7)0.42097 (15)0.0518 (14)
H5A0.44170.78130.41220.062*
H5B0.59560.69630.44250.062*
C60.3350 (8)0.5471 (7)0.43873 (14)0.0457 (13)
C70.4211 (8)0.3581 (7)0.44910 (14)0.0510 (14)
H7A0.49620.36480.47430.061*
H7B0.31230.27260.45290.061*
C80.5546 (7)0.2937 (7)0.41577 (13)0.0441 (12)
C90.2524 (9)0.6355 (8)0.47723 (16)0.0662 (17)
H9A0.35770.64710.49690.099*
H9B0.14730.56140.48820.099*
H9C0.20040.75340.47080.099*
C100.1679 (8)0.5273 (8)0.40747 (16)0.0604 (16)
H10A0.22030.47220.38330.091*
H10B0.11470.64480.40100.091*
H10C0.06350.45240.41840.091*
C110.6670 (6)0.2454 (7)0.31637 (13)0.0424 (12)
C120.4643 (8)0.2067 (8)0.31090 (16)0.0625 (16)
H120.37870.19990.33310.075*
C130.3924 (9)0.1789 (9)0.27221 (18)0.0753 (19)
H130.25680.15610.26840.090*
C140.5172 (10)0.1840 (9)0.23926 (17)0.0712 (19)
H140.46670.16350.21330.085*
C150.7173 (8)0.2196 (9)0.24461 (15)0.0589 (15)
C160.7912 (8)0.2488 (8)0.28321 (13)0.0526 (13)
H160.92720.27100.28680.063*
N10.9468 (8)0.0706 (7)0.40626 (16)0.0636 (13)
O10.6964 (5)0.6824 (5)0.35982 (10)0.0568 (10)
O20.5974 (6)0.1130 (4)0.41360 (10)0.0513 (9)
O30.9540 (7)0.0943 (7)0.44265 (13)0.0948 (16)
O41.0920 (7)0.0381 (7)0.38474 (15)0.0926 (15)
Br10.89492 (12)0.22108 (12)0.200225 (18)0.1030 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.058 (3)0.034 (3)0.052 (3)0.000 (3)0.001 (3)0.005 (3)
C20.053 (3)0.032 (3)0.048 (2)0.006 (3)0.001 (2)0.004 (3)
C30.055 (3)0.031 (3)0.036 (2)0.003 (3)0.004 (2)0.003 (2)
C40.057 (3)0.032 (3)0.045 (3)0.001 (3)0.000 (3)0.001 (2)
C50.064 (3)0.036 (3)0.055 (3)0.003 (3)0.001 (3)0.011 (2)
C60.056 (3)0.042 (3)0.039 (3)0.001 (3)0.002 (2)0.002 (2)
C70.056 (3)0.051 (4)0.047 (3)0.003 (3)0.005 (3)0.007 (2)
C80.056 (3)0.029 (3)0.048 (3)0.002 (3)0.002 (2)0.000 (2)
C90.073 (4)0.063 (4)0.062 (3)0.011 (3)0.015 (3)0.010 (3)
C100.060 (4)0.061 (4)0.060 (3)0.002 (3)0.013 (3)0.001 (3)
C110.049 (3)0.036 (3)0.042 (2)0.001 (3)0.002 (2)0.009 (2)
C120.056 (3)0.073 (4)0.058 (3)0.010 (3)0.002 (3)0.013 (3)
C130.058 (4)0.091 (5)0.077 (4)0.001 (4)0.005 (3)0.029 (4)
C140.089 (5)0.072 (5)0.053 (3)0.006 (4)0.015 (3)0.018 (3)
C150.068 (4)0.058 (4)0.051 (3)0.004 (3)0.003 (3)0.007 (3)
C160.056 (3)0.051 (4)0.050 (3)0.002 (3)0.003 (2)0.007 (3)
N10.076 (4)0.047 (3)0.068 (3)0.002 (3)0.009 (3)0.008 (3)
O10.076 (2)0.036 (2)0.058 (2)0.0071 (19)0.0121 (19)0.0059 (18)
O20.065 (2)0.027 (2)0.062 (2)0.0025 (19)0.008 (2)0.0077 (16)
O30.084 (3)0.138 (4)0.062 (3)0.009 (3)0.014 (3)0.024 (3)
O40.071 (3)0.103 (4)0.104 (3)0.026 (3)0.011 (3)0.006 (3)
Br10.1209 (6)0.1395 (8)0.0487 (3)0.0071 (6)0.0208 (4)0.0096 (4)
Geometric parameters (Å, º) top
C1—O21.411 (6)C8—O21.365 (5)
C1—N11.532 (7)C9—H9A0.9600
C1—C21.536 (7)C9—H9B0.9600
C1—H10.9800C9—H9C0.9600
C2—C31.498 (6)C10—H10A0.9600
C2—C111.515 (6)C10—H10B0.9600
C2—H20.9800C10—H10C0.9600
C3—C81.325 (6)C11—C161.371 (6)
C3—C41.453 (7)C11—C121.396 (6)
C4—O11.220 (5)C12—C131.376 (7)
C4—C51.517 (7)C12—H120.9300
C5—C61.540 (7)C13—C141.368 (8)
C5—H5A0.9700C13—H130.9300
C5—H5B0.9700C14—C151.373 (8)
C6—C101.525 (7)C14—H140.9300
C6—C91.528 (7)C15—C161.380 (6)
C6—C71.545 (7)C15—Br11.882 (5)
C7—C81.491 (6)C16—H160.9300
C7—H7A0.9700N1—O31.211 (6)
C7—H7B0.9700N1—O41.224 (6)
O2—C1—N1107.0 (4)C3—C8—C7127.8 (5)
O2—C1—C2108.6 (4)O2—C8—C7118.3 (4)
N1—C1—C2109.9 (4)C6—C9—H9A109.5
O2—C1—H1110.4C6—C9—H9B109.5
N1—C1—H1110.4H9A—C9—H9B109.5
C2—C1—H1110.4C6—C9—H9C109.5
C3—C2—C11115.9 (4)H9A—C9—H9C109.5
C3—C2—C198.8 (4)H9B—C9—H9C109.5
C11—C2—C1112.4 (4)C6—C10—H10A109.5
C3—C2—H2109.7C6—C10—H10B109.5
C11—C2—H2109.7H10A—C10—H10B109.5
C1—C2—H2109.7C6—C10—H10C109.5
C8—C3—C4121.1 (5)H10A—C10—H10C109.5
C8—C3—C2109.9 (4)H10B—C10—H10C109.5
C4—C3—C2129.0 (4)C16—C11—C12119.2 (4)
O1—C4—C3122.8 (5)C16—C11—C2119.6 (4)
O1—C4—C5122.1 (5)C12—C11—C2121.0 (4)
C3—C4—C5114.9 (4)C13—C12—C11119.2 (5)
C4—C5—C6115.6 (4)C13—C12—H12120.4
C4—C5—H5A108.4C11—C12—H12120.4
C6—C5—H5A108.4C12—C13—C14121.1 (6)
C4—C5—H5B108.4C12—C13—H13119.4
C6—C5—H5B108.4C14—C13—H13119.4
H5A—C5—H5B107.4C13—C14—C15119.8 (5)
C10—C6—C9109.6 (4)C13—C14—H14120.1
C10—C6—C7109.6 (4)C15—C14—H14120.1
C9—C6—C7109.6 (4)C14—C15—C16119.8 (5)
C10—C6—C5109.1 (4)C14—C15—Br1121.0 (4)
C9—C6—C5109.2 (4)C16—C15—Br1119.2 (4)
C7—C6—C5109.7 (4)C11—C16—C15120.9 (5)
C8—C7—C6110.3 (4)C11—C16—H16119.6
C8—C7—H7A109.6C15—C16—H16119.6
C6—C7—H7A109.6O3—N1—O4124.7 (5)
C8—C7—H7B109.6O3—N1—C1119.6 (5)
C6—C7—H7B109.6O4—N1—C1115.5 (5)
H7A—C7—H7B108.1C8—O2—C1105.9 (4)
C3—C8—O2113.9 (4)
O2—C1—C2—C316.1 (5)C6—C7—C8—C317.4 (7)
N1—C1—C2—C3100.7 (5)C6—C7—C8—O2161.3 (4)
O2—C1—C2—C11106.8 (4)C3—C2—C11—C16137.5 (5)
N1—C1—C2—C11136.5 (4)C1—C2—C11—C16109.9 (6)
C11—C2—C3—C8110.0 (5)C3—C2—C11—C1246.8 (7)
C1—C2—C3—C810.3 (5)C1—C2—C11—C1265.8 (7)
C11—C2—C3—C472.7 (7)C16—C11—C12—C132.2 (10)
C1—C2—C3—C4167.0 (5)C2—C11—C12—C13177.9 (5)
C8—C3—C4—O1177.6 (5)C11—C12—C13—C141.6 (10)
C2—C3—C4—O10.6 (9)C12—C13—C14—C150.7 (11)
C8—C3—C4—C52.2 (7)C13—C14—C15—C160.4 (11)
C2—C3—C4—C5174.9 (5)C13—C14—C15—Br1178.2 (5)
O1—C4—C5—C6152.9 (5)C12—C11—C16—C151.9 (9)
C3—C4—C5—C631.6 (7)C2—C11—C16—C15177.7 (5)
C4—C5—C6—C1067.6 (6)C14—C15—C16—C111.0 (10)
C4—C5—C6—C9172.6 (5)Br1—C15—C16—C11178.8 (4)
C4—C5—C6—C752.5 (6)O2—C1—N1—O310.3 (7)
C10—C6—C7—C876.6 (5)C2—C1—N1—O3107.4 (6)
C9—C6—C7—C8163.1 (4)O2—C1—N1—O4174.1 (5)
C5—C6—C7—C843.2 (5)C2—C1—N1—O468.1 (6)
C4—C3—C8—O2176.5 (4)C3—C8—O2—C19.9 (6)
C2—C3—C8—O21.1 (6)C7—C8—O2—C1171.2 (4)
C4—C3—C8—C74.7 (8)N1—C1—O2—C8102.2 (4)
C2—C3—C8—C7177.7 (4)C2—C1—O2—C816.4 (5)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···O1i0.982.293.165 (6)148
C5—H5A···O2ii0.972.663.351 (6)129
C14—H14···O1iii0.932.653.559 (7)167
Symmetry codes: (i) x, y1, z; (ii) x, y+1, z; (iii) x+1, y1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···O1i0.9792.2903.165 (6)148.27
C5—H5A···O2ii0.9692.6573.351 (6)128.79
C14—H14···O1iii0.9312.6453.559 (7)167.32
Symmetry codes: (i) x, y1, z; (ii) x, y+1, z; (iii) x+1, y1/2, z+1/2.
 

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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