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ISSN: 2056-9890

2,2′-[Ethane-1,2-diylbis(­­oxy)]dibenz­alde­hyde

aDepartment of Physics, Faculty of Sciences, Erciyes University, 38039 Kayseri, Turkey, bChemistry and Environmental Division, Manchester Metropolitan University, Manchester M1 5GD, England, cChemistry Department, Faculty of Science, Mini University, 61519 El-Minia, Egypt, dSchool of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, England, eChemistry Department, Faculty of Science, Sohag University, 82524-Sohag, Egypt, and fKirkuk University, College of Science, Department of Chemistry, Kirkuk, Iraq
*Correspondence e-mail: shaabankamel@yahoo.com

(Received 9 July 2013; accepted 10 July 2013; online 13 July 2013)

In the title compound, C16H14O4, the benzene rings are inclined at a dihedral angle of 75.14 (9)°. The torsion angle of the bridging O—C—C—O group is −76.50 (11)°. In the crystal, mol­ecules are linked by C—H⋯O hydrogen bonds, forming C(6) chains along [100]. Furthermore, C—H⋯π inter­actions and ππ stacking inter­actions [centroid–centroid distances = 3.6957 (7) and 3.6735 (8) Å] contribute to the stability of the crystal packing.

Related literature

For the synthesis and utlization of bis-funtionalized compounds, see: Holland et al. (2007[Holland, J. P., Aigbirhio, F. I., Betts, H. M., Bonnitcha, P. D., Burke, P., Christlieb, M., Churchill, G. C., Cowley, A. R., Dilworth, J. R., Donnelly, P. S., Green, J. C., Peach, J. M., Vasudevan, S. R. & Warren, J. E. (2007). Inorg. Chem. 46, 465-485.]); Pedras et al. (2010[Pedras, B., Gallego, D., Figueiredo, P., Nunes-Miranda, J. D., Capelo, J. L. & Lodeiro, C. (2010). Molbank, 2, M683.]); Mabkhot et al. (2012[Mabkhot, Y. N., Barakat, A., Al-Majid, A. M. & Alshahrani, S. A. (2012). Int. J. Mol. Sci. 13, 2263-2275.]); Gavrilova & Bosnich (2004[Gavrilova, A. L. & Bosnich, B. (2004). Chem. Rev. 104, 349-383.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For graph-set theory, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C16H14O4

  • Mr = 270.27

  • Triclinic, [P \overline 1]

  • a = 7.7571 (1) Å

  • b = 8.3277 (1) Å

  • c = 11.2965 (1) Å

  • α = 82.283 (7)°

  • β = 75.839 (7)°

  • γ = 66.823 (6)°

  • V = 649.87 (4) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 120 K

  • 0.62 × 0.44 × 0.22 mm

Data collection
  • Rigaku R-AXIS conversion diffractometer

  • Absorption correction: multi-scan (CrystalClear-SM Expert; Rigaku, 2012[Rigaku (2012). CrystalClear-SM Expert. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.878, Tmax = 1.000

  • 9715 measured reflections

  • 2969 independent reflections

  • 2862 reflections with I > 2σ(I)

  • Rint = 0.031

Refinement
  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.101

  • S = 1.07

  • 2969 reflections

  • 182 parameters

  • H-atom parameters constrained

  • Δρmax = 0.34 e Å−3

  • Δρmin = −0.19 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the C3–C8 and C10–C15 benzene rings, respectively.

D—H⋯A D—H H⋯A DA D—H⋯A
C8—H8⋯O3i 0.95 2.44 3.2508 (17) 144
C2—H2ACg1ii 0.99 2.68 3.4220 (12) 132
C2—H2BCg2iii 0.99 2.70 3.5964 (14) 151
Symmetry codes: (i) x-1, y, z; (ii) -x, -y+1, -z+1; (iii) -x, -y+1, -z.

Data collection: CrystalClear-SM Expert (Rigaku, 2012[Rigaku (2012). CrystalClear-SM Expert. Rigaku Corporation, Tokyo, Japan.]); cell refinement: CrystalClear-SM Expert; data reduction: CrystalClear-SM Expert; 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.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

The synthesis of bis functionalized compounds has attracted the interest of chemists in chemical industry. Such compounds are considered as significant precursores for building blocks of vital molecules in different studies such as supramolecular chemistry and nanoscience (Holland et al., 2007), bioactive bis heterocyclic compounds (Pedras et al., 2010; Mabkhot et al., 2012), and binucleating ligand designs (Gavrilova & Bosnich, 2004). In this concept the title compound has been synthesized among several derivatives of bis functionalized compounds as precursers for the synthesis of a series of macromolecular compounds.

The dihedral angle between the two benzene rings (C3–C8 and C10–C15) of the title compound (Fig. 1) is 75.14 (9)°. The torsion angle of the bridge O–C–C–O group is -76.50 (11)°. The C3–C4–C9–O3 and C10–C11–C16–O4 torsion angles of the two benzaldehyde groups are 175.10 (11) and -175.87 (13)°, respectively. Thus, they are almost coplanar with the rings to which they are attached. The bond lengths are normal (Allen et al., 1987).

In the crystal, molecules are connected by C–H···O hydrogen bonds, generating infinite chains with the graph-set motif C(6) (Table 1, Fig. 2; Bernstein et al., 1995) along the a axis. In addition, C–H···π interactions (Table 1) and π-π stacking interactions [Cg1···Cg1( - x, 2 - y, 1 - z) = 3.6957 (7) Å and Cg2···Cg2( 1 - x, 1 - y, 1 - z) = 3.6735 (8) Å; where Cg1 and Cg2 are the centroids of the C3–C8 and C10–C15 benzene rings, respectively] contribute to stabilize the crystal structure.

Related literature top

For the synthesis and utlization of bis-funtionalized compounds, see: Holland et al. (2007); Pedras et al. (2010); Mabkhot et al. (2012); Gavrilova & Bosnich (2004). For bond-length data, see: Allen et al. (1987). For graph-set theory, see: Bernstein et al. (1995).

Experimental top

A solution of 1.22 g m (0.01 mol) salicyldehyde in hot ethanolic KOH (prepared by dissolving 560 mg (0.01 mol) KOH in 100 ml of absolute ethanol) was stirred until a clear solution was obtained, which was then evaporated under vacuum. The residue was dissolved in DMF (25 ml) and 940 mg (0.005 mol) of dibromoethane was added. The reaction mixture was refluxed for 5 minutes, during which KBr was separated out. The solvent was then removed in vacuo and the remaining solid was washed with water and crystallized from ethanol to give high quality crystals (Mp. 393 K) suitable for X-ray analysis in an good yield (84%).

Refinement top

All H atoms were found in a difference map, but placed geometrically with C—H = 0.95 Å (aromatic H) and 0.99 Å (methylene H) and were refined using a riding model with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: CrystalClear-SM Expert (Rigaku, 2012); cell refinement: CrystalClear-SM Expert (Rigaku, 2012); data reduction: CrystalClear-SM Expert (Rigaku, 2012); 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) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. View of the molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids for non-H atoms are drawn at the 50% probability level.
[Figure 2] Fig. 2. Partial packing diagram of the title compound showing hydrogen bonds as dashed lines. H atoms not involved in hydrogen bonds have been omitted for clarity.
2,2'-[Ethane-1,2-diylbis(oxy)]dibenzaldehyde top
Crystal data top
C16H14O4Z = 2
Mr = 270.27F(000) = 284
Triclinic, P1Dx = 1.381 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71075 Å
a = 7.7571 (1) ÅCell parameters from 4015 reflections
b = 8.3277 (1) Åθ = 1.9–27.5°
c = 11.2965 (1) ŵ = 0.10 mm1
α = 82.283 (7)°T = 120 K
β = 75.839 (7)°Block, colourless
γ = 66.823 (6)°0.62 × 0.44 × 0.22 mm
V = 649.87 (4) Å3
Data collection top
Rigaku R-AXIS conversion
diffractometer
2969 independent reflections
Radiation source: Sealed Tube2862 reflections with I > 2σ(I)
Graphite Monochromator monochromatorRint = 0.031
Detector resolution: 10.0000 pixels mm-1θmax = 27.5°, θmin = 2.9°
profile data from ω–scansh = 108
Absorption correction: multi-scan
(CrystalClear-SM Expert; Rigaku, 2012)
k = 1010
Tmin = 0.878, Tmax = 1.000l = 1414
9715 measured reflections
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.039 W = 1/[Σ2(FO2) + (0.0397P)2 + 0.2051P] WHERE P = (FO2 + 2FC2)/3
wR(F2) = 0.101(Δ/σ)max < 0.001
S = 1.07Δρmax = 0.34 e Å3
2969 reflectionsΔρmin = 0.19 e Å3
182 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), FC*=KFC[1+0.001XFC2Λ3/SIN(2Θ)]-1/4
0 restraintsExtinction coefficient: 0.039 (4)
Crystal data top
C16H14O4γ = 66.823 (6)°
Mr = 270.27V = 649.87 (4) Å3
Triclinic, P1Z = 2
a = 7.7571 (1) ÅMo Kα radiation
b = 8.3277 (1) ŵ = 0.10 mm1
c = 11.2965 (1) ÅT = 120 K
α = 82.283 (7)°0.62 × 0.44 × 0.22 mm
β = 75.839 (7)°
Data collection top
Rigaku R-AXIS conversion
diffractometer
2969 independent reflections
Absorption correction: multi-scan
(CrystalClear-SM Expert; Rigaku, 2012)
2862 reflections with I > 2σ(I)
Tmin = 0.878, Tmax = 1.000Rint = 0.031
9715 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0390 restraints
wR(F2) = 0.101H-atom parameters constrained
S = 1.07Δρmax = 0.34 e Å3
2969 reflectionsΔρmin = 0.19 e Å3
182 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating -R-factor-obs 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
O10.02681 (11)0.67683 (11)0.39979 (7)0.0234 (2)
O20.09562 (12)0.63138 (10)0.13897 (7)0.0229 (2)
O30.42624 (12)0.70766 (12)0.54585 (8)0.0310 (3)
O40.29048 (14)0.91784 (11)0.12808 (8)0.0335 (3)
C10.10587 (16)0.66169 (14)0.33728 (10)0.0222 (3)
C20.00997 (16)0.53887 (14)0.23588 (10)0.0221 (3)
C30.04430 (16)0.76808 (13)0.50371 (9)0.0198 (3)
C40.09320 (16)0.78082 (14)0.55953 (10)0.0203 (3)
C50.03276 (17)0.87486 (14)0.66511 (10)0.0238 (3)
C60.16055 (18)0.95186 (15)0.71668 (10)0.0264 (3)
C70.29501 (17)0.93499 (15)0.66234 (10)0.0254 (3)
C80.23910 (16)0.84489 (14)0.55568 (10)0.0225 (3)
C90.29937 (16)0.69362 (15)0.50767 (10)0.0235 (3)
C100.20867 (15)0.54157 (14)0.03822 (10)0.0201 (3)
C110.28537 (16)0.63720 (14)0.05755 (10)0.0205 (3)
C120.40808 (16)0.55234 (15)0.16216 (10)0.0237 (3)
C130.45243 (17)0.37632 (16)0.17322 (11)0.0267 (3)
C140.37194 (17)0.28415 (15)0.07953 (11)0.0255 (3)
C150.25049 (17)0.36520 (15)0.02579 (10)0.0228 (3)
C160.23854 (17)0.82470 (15)0.04713 (11)0.0252 (3)
H1A0.180700.777500.303700.0270*
H1B0.196200.615200.394200.0270*
H2A0.110900.436600.265900.0270*
H2B0.073700.496500.206000.0270*
H50.125000.886200.701900.0290*
H60.201201.015800.788600.0320*
H70.427500.986000.698800.0300*
H80.332400.835800.518800.0270*
H90.335500.621900.440200.0280*
H120.461700.616000.226400.0280*
H130.537200.318800.244200.0320*
H140.400600.163800.087800.0310*
H150.196200.300800.089000.0270*
H160.162700.876300.027800.0300*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0200 (4)0.0302 (4)0.0205 (4)0.0089 (3)0.0034 (3)0.0061 (3)
O20.0284 (4)0.0212 (4)0.0187 (4)0.0107 (3)0.0016 (3)0.0015 (3)
O30.0251 (5)0.0358 (5)0.0361 (5)0.0147 (4)0.0104 (4)0.0025 (4)
O40.0444 (6)0.0263 (4)0.0336 (5)0.0190 (4)0.0086 (4)0.0051 (4)
C10.0208 (5)0.0257 (5)0.0218 (5)0.0099 (4)0.0053 (4)0.0010 (4)
C20.0255 (6)0.0231 (5)0.0197 (5)0.0118 (4)0.0047 (4)0.0009 (4)
C30.0227 (5)0.0180 (5)0.0180 (5)0.0084 (4)0.0031 (4)0.0013 (4)
C40.0231 (5)0.0192 (5)0.0193 (5)0.0100 (4)0.0044 (4)0.0035 (4)
C50.0310 (6)0.0215 (5)0.0222 (5)0.0123 (5)0.0090 (4)0.0026 (4)
C60.0341 (6)0.0218 (5)0.0203 (5)0.0087 (5)0.0028 (5)0.0026 (4)
C70.0240 (6)0.0220 (5)0.0244 (5)0.0059 (4)0.0002 (4)0.0003 (4)
C80.0215 (5)0.0230 (5)0.0228 (5)0.0090 (4)0.0043 (4)0.0006 (4)
C90.0240 (6)0.0250 (5)0.0219 (5)0.0107 (4)0.0056 (4)0.0035 (4)
C100.0199 (5)0.0228 (5)0.0190 (5)0.0077 (4)0.0068 (4)0.0013 (4)
C110.0210 (5)0.0220 (5)0.0210 (5)0.0093 (4)0.0077 (4)0.0009 (4)
C120.0245 (6)0.0262 (6)0.0212 (5)0.0103 (4)0.0055 (4)0.0005 (4)
C130.0284 (6)0.0272 (6)0.0217 (5)0.0079 (5)0.0029 (4)0.0045 (4)
C140.0299 (6)0.0206 (5)0.0264 (6)0.0082 (4)0.0079 (5)0.0030 (4)
C150.0264 (6)0.0224 (5)0.0219 (5)0.0111 (4)0.0071 (4)0.0015 (4)
C160.0296 (6)0.0234 (5)0.0246 (5)0.0106 (5)0.0087 (5)0.0001 (4)
Geometric parameters (Å, º) top
O1—C11.4337 (16)C12—C131.3834 (17)
O1—C31.3611 (13)C13—C141.3910 (18)
O2—C21.4332 (14)C14—C151.3876 (17)
O2—C101.3593 (13)C1—H1A0.9900
O3—C91.2166 (17)C1—H1B0.9900
O4—C161.2147 (15)C2—H2A0.9900
C1—C21.5011 (15)C2—H2B0.9900
C3—C41.4081 (18)C5—H50.9500
C3—C81.3940 (18)C6—H60.9500
C4—C51.3942 (15)C7—H70.9500
C4—C91.4731 (18)C8—H80.9500
C5—C61.3839 (19)C9—H90.9500
C6—C71.392 (2)C12—H120.9500
C7—C81.3906 (16)C13—H130.9500
C10—C111.4090 (16)C14—H140.9500
C10—C151.3929 (16)C15—H150.9500
C11—C121.3951 (16)C16—H160.9500
C11—C161.4717 (16)
C1—O1—C3118.45 (10)C2—C1—H1A110.00
C2—O2—C10117.35 (8)C2—C1—H1B110.00
O1—C1—C2107.09 (10)H1A—C1—H1B109.00
O2—C2—C1108.23 (9)O2—C2—H2A110.00
O1—C3—C4115.69 (11)O2—C2—H2B110.00
O1—C3—C8124.17 (11)C1—C2—H2A110.00
C4—C3—C8120.14 (10)C1—C2—H2B110.00
C3—C4—C5119.49 (11)H2A—C2—H2B108.00
C3—C4—C9120.26 (10)C4—C5—H5120.00
C5—C4—C9120.24 (12)C6—C5—H5120.00
C4—C5—C6120.50 (12)C5—C6—H6120.00
C5—C6—C7119.52 (11)C7—C6—H6120.00
C6—C7—C8121.24 (12)C6—C7—H7119.00
C3—C8—C7119.08 (12)C8—C7—H7119.00
O3—C9—C4124.12 (11)C3—C8—H8120.00
O2—C10—C11116.23 (9)C7—C8—H8120.00
O2—C10—C15123.99 (10)O3—C9—H9118.00
C11—C10—C15119.79 (10)C4—C9—H9118.00
C10—C11—C12119.48 (10)C11—C12—H12120.00
C10—C11—C16120.45 (10)C13—C12—H12120.00
C12—C11—C16120.07 (11)C12—C13—H13120.00
C11—C12—C13120.59 (11)C14—C13—H13120.00
C12—C13—C14119.48 (11)C13—C14—H14119.00
C13—C14—C15121.06 (11)C15—C14—H14119.00
C10—C15—C14119.57 (11)C10—C15—H15120.00
O4—C16—C11124.30 (11)C14—C15—H15120.00
O1—C1—H1A110.00O4—C16—H16118.00
O1—C1—H1B110.00C11—C16—H16118.00
C3—O1—C1—C2173.57 (9)C4—C5—C6—C70.04 (16)
C1—O1—C3—C81.68 (15)C5—C6—C7—C81.24 (17)
C1—O1—C3—C4178.90 (9)C6—C7—C8—C30.98 (17)
C10—O2—C2—C1179.42 (10)O2—C10—C11—C12177.80 (11)
C2—O2—C10—C152.20 (18)O2—C10—C11—C161.51 (18)
C2—O2—C10—C11177.73 (11)C15—C10—C11—C122.27 (19)
O1—C1—C2—O276.50 (11)C15—C10—C11—C16178.42 (12)
O1—C3—C4—C91.99 (15)O2—C10—C15—C14178.22 (12)
C8—C3—C4—C51.78 (16)C11—C10—C15—C141.9 (2)
O1—C3—C8—C7179.93 (9)C10—C11—C12—C131.0 (2)
C4—C3—C8—C70.54 (16)C16—C11—C12—C13179.70 (13)
C8—C3—C4—C9177.46 (10)C10—C11—C16—O4175.87 (13)
O1—C3—C4—C5178.78 (10)C12—C11—C16—O44.8 (2)
C3—C4—C9—O3175.10 (11)C11—C12—C13—C140.7 (2)
C5—C4—C9—O35.67 (18)C12—C13—C14—C151.1 (2)
C3—C4—C5—C61.53 (16)C13—C14—C15—C100.2 (2)
C9—C4—C5—C6177.71 (10)
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the C3–C8 and C10–C15 benzene rings, respectively.
D—H···AD—HH···AD···AD—H···A
C8—H8···O3i0.952.443.2508 (17)144
C9—H9···O10.952.402.7412 (16)101
C16—H16···O20.952.422.7561 (15)101
C2—H2A···Cg1ii0.992.683.4220 (12)132
C2—H2B···Cg2iii0.992.703.5964 (14)151
Symmetry codes: (i) x1, y, z; (ii) x, y+1, z+1; (iii) x, y+1, z.
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the C3–C8 and C10–C15 benzene rings, respectively.
D—H···AD—HH···AD···AD—H···A
C8—H8···O3i0.952.443.2508 (17)144
C2—H2A···Cg1ii0.992.683.4220 (12)132
C2—H2B···Cg2iii0.992.703.5964 (14)151
Symmetry codes: (i) x1, y, z; (ii) x, y+1, z+1; (iii) x, y+1, z.
 

Acknowledgements

Manchester Metropolitan University and Erciyes University are gratefully acknowledged for supporting this study.

References

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