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

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ISSN: 2056-9890

(1S,3R,8R,9S,11R)-2,2-Di­bromo-10,10-di­chloro-3,7,7,11-tetra­methyl­tetra­cyclo­[6.5.0.01,3.09,11]trideca­ne

aLaboratoire de Chimie Biomoléculaire, Substances Naturelles et Réactivité "Unité Associée au CNRST (URAC16)", Université Cadi Ayyad, Faculté des Sciences Semlalia, BP 2390, Bd My Abdellah, 40000 Marrakech, Morocco, and bLaboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V-Agdal, Avenue Ibn Battouta, BP 1014, Rabat, Morocco
*Correspondence e-mail: berraho@uca.ma

(Received 26 March 2013; accepted 3 April 2013; online 13 April 2013)

The title compound, C17H24Br2Cl2, was synthesized from β-himachalene (3,5,5,9-tetra­methyl-2,4a,5,6,7,8-hexa­hydro-1H-benzo­cyclo­heptene), which was isolated from the essential oil of the Atlas cedar (Cedrus Atlantica). The mol­ecule contains fused six-, seven- and two three-membered rings. The six-membered ring has a half-chair conformation, while the seven-membered ring displays a boat conformation. The absolute structure was unambiguously established from anomalous dispersion effects. The crystal packing exhibits no short inter­molecular contacts.

Related literature

For the crystal structures of related compounds, see: Ourhriss et al. (2013[Ourhriss, N., Benharref, A., Saadi, M., El Ammari, L. & Berraho, M. (2013). Acta Cryst. E69, o275.]); Oukhrib et al. (2013a[Oukhrib, A., Benharref, A., Saadi, M., Berraho, M. & El Ammari, L. (2013a). Acta Cryst. E69, o521-o522.],b[Oukhrib, A., Benharref, A., Saadi, M., Berraho, M. & El Ammari, L. (2013b). Acta Cryst. E69, o589-o590.]). For puckering param­eters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C17H24Br2Cl2

  • Mr = 459.08

  • Monoclinic, P 21

  • a = 9.0112 (6) Å

  • b = 11.6772 (8) Å

  • c = 9.0849 (6) Å

  • β = 108.045 (5)°

  • V = 908.94 (11) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 4.75 mm−1

  • T = 296 K

  • 0.45 × 0.34 × 0.29 mm

Data collection
  • Bruker X8 APEX diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) Tmin = 0.739, Tmax = 0.867

  • 6676 measured reflections

  • 3720 independent reflections

  • 2910 reflections with I > 2σ(I)

  • Rint = 0.034

Refinement
  • R[F2 > 2σ(F2)] = 0.038

  • wR(F2) = 0.092

  • S = 1.03

  • 3720 reflections

  • 190 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.64 e Å−3

  • Δρmin = −0.79 e Å−3

  • Absolute structure: Flack & Bernardinelli (2000[Flack, H. D. & Bernardinelli, G. (2000). J. Appl. Cryst. 33, 1143-1148.]), 1096 Friedel pairs

  • Flack parameter: 0.039 (10)

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

As a continuation of our structural study of β-himachalene derivatives isolated from the essential oil of the Atlas cedar (Cedrus Atlantica) (Ourhriss et al., 2013; Oukhrib et al., 2013a,b), we present here the crystal structure of the title compound, (1S,3R,8R,9S,11R)-2,2-dibromo-10,10-dichloro-3,7,7,11- tetramethyltetracyclo[6.5.0.01,3.09,11]tridecane, (I).

In (I) (Fig. 1), the molecule contains a fused six- and seven-membered rings, which are fused to two three-membered rings. The six-membered ring has a half chair conformation as indicated by the total puckering amplitude QT = 0.446 (5) Å and spherical polar angle θ = 140.8 (6)° and ϕ2 = 143 (1)°, whereas the seven-membered ring displays a boat conformation with QT = 1.122 (5) Å, θ2 = 87.4 (3)°, ϕ2 = -48.2 (3)° and ϕ3 = -118 (5)° (Cremer & Pople, 1975). The three-membered rings (C1/C2/C3) and (C9/C10/C11) are nearly perpendicular to the six and seven-membered rings (C1/C8–C13)and (C1/C3–C8), with a dihedral angles of 84.1 (4) and 80.6 (4), respectively. Owing to the presence of Br and Cl atoms, the absolute configuration could be fully confirmed from anomalous dispersion effects, by refining the Flack parameter as C1(S),C3(R),C8(R),C9(S), and C11(R). The crystal packing exhibits no short intermolecular contacts.

Related literature top

For the crystal structures of related compounds, see: Ourhriss et al. (2013); Oukhrib et al. (2013a,b). For puckering parameters, see: Cremer & Pople (1975).

Experimental top

A solution containing 4 g (10 mmol) of (1S,3R,8S)-2,2-dibromo- 3,7,7,10- tetramethyltricyclo[6.4.0.01,3]dodec-9-ene and 1 ml (12.4 mmol) of CHCl3 in 40 ml of dichloromethane was added dropwise at 273 K over 30 min to 1 g (25 mmol) of pulverized sodium hydroxide and 40 mg of N–benzyltriethylam monium chloride placed in a 100 ml three–necked flask. After stirring at room temperature for 2 h, the mixture was filtered on celite and concentrated in vacuum. The residue obtained was chromatographed on silicagel column impregnated with silver nitrate (10%) with a mixture of hexane - ethyl acetate (96–4) used as eluent. The two diastereoisomers (1S,3R,8S,9S,11R)- 2,2-Dibromo-10,10-dichloro-3,7,7,11-tetramethyltetracyclo[6.5.0.01,3.0 9,11]tridecane(X) and its isomer (1S,3R,8S,9R,11S)-2,2-Dibromo-10,10- dichloro-3,7,7,11-tetramethyltetracyclo[6.5.0.01,3.09,11]tridecane(Y) were obtained by this procedure in a 80/20 ratio and a combined yield of 65% (3 g; 6.5 mmol). The title compound (isomer X) was recrystallized from hexane.

Refinement top

All H atoms were fixed geometrically and treated as riding with C—H = 0.96 Å (methyl),0.97 Å (methylene), 0.98 Å (methine) with Uiso(H) = 1.2 Ueq(methylene, methine) and Uiso(H) = 1.5 Ueq(methyl). The space group is non-centrosymmetric and the polar axis restraint is generated automatically by SHELXL program. The 1096 Friedel opposites reflections are not merged.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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: PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. : Molecular structure of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability. level. H atoms are represented as small spheres of arbitrary radii.
(1S,3R,8R,9S,11R)-2,2-Dibromo-10,10-dichloro-3,7,7,11-tetramethyltetracyclo[6.5.0.01,3.09,11]tridecane top
Crystal data top
C17H24Br2Cl2F(000) = 460
Mr = 459.08Dx = 1.677 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 3720 reflections
a = 9.0112 (6) Åθ = 2.8–29.6°
b = 11.6772 (8) ŵ = 4.75 mm1
c = 9.0849 (6) ÅT = 296 K
β = 108.045 (5)°Block, colourless
V = 908.94 (11) Å30.45 × 0.34 × 0.29 mm
Z = 2
Data collection top
Bruker X8 APEX
diffractometer
3720 independent reflections
Radiation source: fine-focus sealed tube2910 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
ϕ and ω scansθmax = 29.6°, θmin = 2.8°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008)
h = 1212
Tmin = 0.739, Tmax = 0.867k = 1615
6676 measured reflectionsl = 1212
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)] = 0.038H-atom parameters constrained
wR(F2) = 0.092 w = 1/[σ2(Fo2) + (0.0333P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max = 0.001
3720 reflectionsΔρmax = 0.64 e Å3
190 parametersΔρmin = 0.79 e Å3
1 restraintAbsolute structure: Flack & Bernardinelli (2000), 1096 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.039 (10)
Crystal data top
C17H24Br2Cl2V = 908.94 (11) Å3
Mr = 459.08Z = 2
Monoclinic, P21Mo Kα radiation
a = 9.0112 (6) ŵ = 4.75 mm1
b = 11.6772 (8) ÅT = 296 K
c = 9.0849 (6) Å0.45 × 0.34 × 0.29 mm
β = 108.045 (5)°
Data collection top
Bruker X8 APEX
diffractometer
3720 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008)
2910 reflections with I > 2σ(I)
Tmin = 0.739, Tmax = 0.867Rint = 0.034
6676 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.038H-atom parameters constrained
wR(F2) = 0.092Δρmax = 0.64 e Å3
S = 1.03Δρmin = 0.79 e Å3
3720 reflectionsAbsolute structure: Flack & Bernardinelli (2000), 1096 Friedel pairs
190 parametersAbsolute structure parameter: 0.039 (10)
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
C10.8734 (5)0.4080 (3)0.7265 (5)0.0211 (8)
C20.9989 (5)0.3302 (4)0.6990 (6)0.0288 (10)
C31.0234 (4)0.3775 (4)0.8568 (5)0.0275 (9)
C41.0081 (6)0.2965 (4)0.9812 (5)0.0357 (11)
H4A1.11020.26571.03630.043*
H4B0.94130.23300.93290.043*
C50.9408 (6)0.3542 (5)1.0962 (6)0.0442 (13)
H5A1.02320.39541.17210.053*
H5B0.90140.29601.15070.053*
C60.8095 (6)0.4372 (5)1.0187 (5)0.0387 (12)
H6A0.85670.50270.98490.046*
H6B0.76700.46451.09810.046*
C70.6702 (5)0.3992 (4)0.8798 (5)0.0301 (9)
C80.7181 (4)0.3573 (3)0.7345 (5)0.0206 (8)
H80.73190.27410.74390.025*
C90.5812 (4)0.3798 (4)0.5883 (4)0.0224 (8)
H90.48070.37490.60860.027*
C100.5657 (5)0.3530 (4)0.4239 (5)0.0261 (9)
C110.5826 (5)0.4755 (4)0.4748 (5)0.0278 (9)
C120.7378 (6)0.5328 (4)0.4939 (6)0.0373 (11)
H12A0.71900.61250.46390.045*
H12B0.78560.49700.42340.045*
C130.8528 (5)0.5277 (3)0.6570 (5)0.0277 (9)
H13A0.95340.55560.65460.033*
H13B0.81680.57840.72350.033*
C141.1485 (6)0.4682 (5)0.9207 (7)0.0432 (13)
H14A1.14950.48961.02300.065*
H14B1.12620.53430.85460.065*
H14C1.24860.43770.92470.065*
C150.5843 (6)0.2992 (5)0.9266 (6)0.0453 (13)
H15A0.49810.27630.83940.068*
H15B0.54630.32281.00960.068*
H15C0.65470.23600.96010.068*
C160.5593 (6)0.5035 (5)0.8432 (6)0.0419 (12)
H16A0.61130.56730.81400.063*
H16B0.53050.52320.93330.063*
H16C0.46730.48490.75960.063*
C170.4417 (7)0.5546 (4)0.4175 (7)0.0479 (14)
H17A0.46930.62990.45930.072*
H17B0.35760.52550.45060.072*
H17C0.40950.55810.30650.072*
Cl10.37818 (14)0.30587 (10)0.30591 (14)0.0415 (3)
Cl20.70977 (16)0.28463 (12)0.36234 (14)0.0429 (3)
Br11.11977 (6)0.38295 (6)0.57096 (7)0.05382 (18)
Br20.97449 (6)0.16666 (4)0.66883 (6)0.04537 (16)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0167 (18)0.022 (2)0.023 (2)0.0038 (15)0.0039 (16)0.0013 (15)
C20.019 (2)0.034 (2)0.033 (3)0.0019 (17)0.0085 (19)0.0011 (18)
C30.0185 (18)0.035 (2)0.028 (2)0.005 (2)0.0054 (17)0.004 (2)
C40.028 (2)0.049 (3)0.024 (2)0.003 (2)0.0001 (19)0.003 (2)
C50.044 (3)0.066 (4)0.021 (3)0.004 (3)0.007 (2)0.002 (2)
C60.038 (3)0.057 (3)0.023 (3)0.001 (2)0.013 (2)0.010 (2)
C70.029 (2)0.038 (2)0.028 (2)0.0027 (19)0.0153 (19)0.004 (2)
C80.0199 (18)0.0217 (19)0.022 (2)0.0009 (15)0.0096 (17)0.0021 (15)
C90.0205 (18)0.0241 (18)0.024 (2)0.0013 (18)0.0093 (16)0.0001 (18)
C100.022 (2)0.035 (2)0.019 (2)0.0020 (17)0.0027 (17)0.0016 (16)
C110.029 (2)0.028 (2)0.023 (2)0.0031 (18)0.0021 (19)0.0076 (17)
C120.035 (3)0.030 (2)0.043 (3)0.006 (2)0.007 (2)0.011 (2)
C130.022 (2)0.022 (2)0.037 (3)0.0034 (17)0.0067 (19)0.0028 (18)
C140.023 (2)0.054 (3)0.047 (3)0.008 (2)0.004 (2)0.005 (2)
C150.043 (3)0.068 (3)0.033 (3)0.005 (3)0.024 (3)0.004 (3)
C160.036 (3)0.051 (3)0.044 (3)0.011 (2)0.019 (3)0.008 (2)
C170.042 (3)0.038 (3)0.053 (3)0.012 (2)0.001 (3)0.003 (2)
Cl10.0330 (6)0.0449 (7)0.0341 (7)0.0066 (5)0.0077 (5)0.0011 (5)
Cl20.0438 (7)0.0613 (8)0.0262 (6)0.0125 (6)0.0144 (5)0.0040 (5)
Br10.0336 (3)0.0840 (4)0.0516 (3)0.0014 (3)0.0244 (3)0.0083 (3)
Br20.0452 (3)0.0386 (2)0.0525 (3)0.0134 (3)0.0156 (3)0.0033 (3)
Geometric parameters (Å, º) top
C1—C131.522 (6)C9—C111.524 (6)
C1—C21.530 (6)C9—H90.9800
C1—C31.537 (5)C10—C111.496 (6)
C1—C81.542 (5)C10—Cl21.756 (4)
C2—C31.488 (6)C10—Cl11.785 (4)
C2—Br11.924 (4)C11—C121.511 (6)
C2—Br21.932 (4)C11—C171.525 (7)
C3—C41.513 (6)C12—C131.524 (7)
C3—C141.524 (7)C12—H12A0.9700
C4—C51.519 (7)C12—H12B0.9700
C4—H4A0.9700C13—H13A0.9700
C4—H4B0.9700C13—H13B0.9700
C5—C61.523 (7)C14—H14A0.9600
C5—H5A0.9700C14—H14B0.9600
C5—H5B0.9700C14—H14C0.9600
C6—C71.544 (6)C15—H15A0.9600
C6—H6A0.9700C15—H15B0.9600
C6—H6B0.9700C15—H15C0.9600
C7—C151.531 (7)C16—H16A0.9600
C7—C161.545 (7)C16—H16B0.9600
C7—C81.587 (5)C16—H16C0.9600
C8—C91.529 (6)C17—H17A0.9600
C8—H80.9800C17—H17B0.9600
C9—C101.490 (6)C17—H17C0.9600
C13—C1—C2118.6 (3)C10—C9—H9111.8
C13—C1—C3119.8 (3)C11—C9—H9111.8
C2—C1—C358.1 (3)C8—C9—H9111.8
C13—C1—C8112.1 (3)C9—C10—C1161.4 (3)
C2—C1—C8120.5 (3)C9—C10—Cl2124.4 (3)
C3—C1—C8118.0 (3)C11—C10—Cl2121.3 (3)
C3—C2—C161.2 (3)C9—C10—Cl1116.4 (3)
C3—C2—Br1121.4 (3)C11—C10—Cl1117.8 (3)
C1—C2—Br1119.6 (3)Cl2—C10—Cl1108.9 (2)
C3—C2—Br2118.7 (3)C10—C11—C12117.4 (4)
C1—C2—Br2123.5 (3)C10—C11—C959.1 (3)
Br1—C2—Br2106.9 (2)C12—C11—C9116.6 (4)
C2—C3—C4117.9 (4)C10—C11—C17118.6 (4)
C2—C3—C14119.7 (4)C12—C11—C17114.5 (4)
C4—C3—C14112.2 (4)C9—C11—C17119.7 (4)
C2—C3—C160.7 (3)C11—C12—C13114.9 (4)
C4—C3—C1117.3 (3)C11—C12—H12A108.5
C14—C3—C1120.2 (4)C13—C12—H12A108.5
C3—C4—C5112.6 (4)C11—C12—H12B108.5
C3—C4—H4A109.1C13—C12—H12B108.5
C5—C4—H4A109.1H12A—C12—H12B107.5
C3—C4—H4B109.1C1—C13—C12113.5 (4)
C5—C4—H4B109.1C1—C13—H13A108.9
H4A—C4—H4B107.8C12—C13—H13A108.9
C4—C5—C6112.5 (4)C1—C13—H13B108.9
C4—C5—H5A109.1C12—C13—H13B108.9
C6—C5—H5A109.1H13A—C13—H13B107.7
C4—C5—H5B109.1C3—C14—H14A109.5
C6—C5—H5B109.1C3—C14—H14B109.5
H5A—C5—H5B107.8H14A—C14—H14B109.5
C5—C6—C7120.9 (4)C3—C14—H14C109.5
C5—C6—H6A107.1H14A—C14—H14C109.5
C7—C6—H6A107.1H14B—C14—H14C109.5
C5—C6—H6B107.1C7—C15—H15A109.5
C7—C6—H6B107.1C7—C15—H15B109.5
H6A—C6—H6B106.8H15A—C15—H15B109.5
C15—C7—C6110.2 (4)C7—C15—H15C109.5
C15—C7—C16108.2 (4)H15A—C15—H15C109.5
C6—C7—C16104.9 (4)H15B—C15—H15C109.5
C15—C7—C8106.7 (4)C7—C16—H16A109.5
C6—C7—C8114.0 (3)C7—C16—H16B109.5
C16—C7—C8112.8 (4)H16A—C16—H16B109.5
C9—C8—C1113.2 (3)C7—C16—H16C109.5
C9—C8—C7108.4 (3)H16A—C16—H16C109.5
C1—C8—C7113.9 (3)H16B—C16—H16C109.5
C9—C8—H8107.0C11—C17—H17A109.5
C1—C8—H8107.0C11—C17—H17B109.5
C7—C8—H8107.0H17A—C17—H17B109.5
C10—C9—C1159.5 (3)C11—C17—H17C109.5
C10—C9—C8129.4 (3)H17A—C17—H17C109.5
C11—C9—C8122.7 (3)H17B—C17—H17C109.5

Experimental details

Crystal data
Chemical formulaC17H24Br2Cl2
Mr459.08
Crystal system, space groupMonoclinic, P21
Temperature (K)296
a, b, c (Å)9.0112 (6), 11.6772 (8), 9.0849 (6)
β (°) 108.045 (5)
V3)908.94 (11)
Z2
Radiation typeMo Kα
µ (mm1)4.75
Crystal size (mm)0.45 × 0.34 × 0.29
Data collection
DiffractometerBruker X8 APEX
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2008)
Tmin, Tmax0.739, 0.867
No. of measured, independent and
observed [I > 2σ(I)] reflections
6676, 3720, 2910
Rint0.034
(sin θ/λ)max1)0.694
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.092, 1.03
No. of reflections3720
No. of parameters190
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.64, 0.79
Absolute structureFlack & Bernardinelli (2000), 1096 Friedel pairs
Absolute structure parameter0.039 (10)

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

 

Acknowledgements

The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.

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