Issue contents
Download PDF of article
Download CIF
3D view
Navigation
Highlighting
Dictionary of Crystallography reference
IUPAC Gold Book reference
more ...
Download citation
FormatBIBTeX
EndNote
RefMan
Refer
Medline
CIF
SGML
Plain Text
share
Previous article
Next article
Previous article
Issue contents
Download PDF of article
Download CIF
3D view
Navigation
Highlighting
Dictionary of Crystallography reference
IUPAC Gold Book reference
more ...
Download citation
FormatBIBTeX
EndNote
RefMan
Refer
Medline
CIF
SGML
Plain Text
share
Next article

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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 66| Part 4| April 2010| Page o1006
doi:10.1107/S1600536810010160

2-Bromo­ethyl 2-chloro-6-methyl­quinoline-3-carboxyl­ate

Saida Benzerka,a Abdelmalek Bouraiou,a* Sofiane Bouacida,b Thierry Roisnelc and Ali Belfaitaha

aLaboratoire des Produits Naturels d'Origine Végétale et de Synthèse Organique, PHYSYNOR, Université Mentouri-Constantine, 25000 Constantine, Algeria, bUnité de Recherche de Chimie de l'Environnement et Moléculaire Structurale, CHEMS, Université Mentouri-Constantine 25000, Algeria, and cCentre de Difractométrie X, UMR 6226 CNRS Unité Sciences Chimiques de Rennes, Université de Rennes I, 263 Avenue du Général Leclerc, 35042 Rennes, France
*Correspondence e-mail: bouraiou.abdelmalek@yahoo.fr

(Received 1 March 2010; accepted 18 March 2010; online 31 March 2010)

In the title compound, C13H11BrClNO2, the two rings of the quinoline group are fused in an axial fashion at a dihedral angle of 1.28 (9)°. In the crystal, molecules are arranged in zigzag layers along the c axis. The crystal packing is stabilized by weak C—H⋯O hydrogen bonds and inter­molecular inter­actions between Br and O atoms [Br⋯O= 3.076 (2) Å], resulting in the formation of a three-dimensional network.

Related literature

For our previous work on the preparation of quinoline derivatives, see: Benzerka et al. (2008[Benzerka, S., Bouraiou, A., Bouacida, S., Rhouati, S. & Belfaitah, A. (2008). Acta Cryst. E64, o2089-o2090.]); Ladraa et al. (2009[Ladraa, S., Bouraiou, A., Bouacida, S., Roisnel, T. & Belfaitah, A. (2009). Acta Cryst. C65, o475-o478.], 2010[Ladraa, S., Bouraiou, A., Bouacida, S., Roisnel, T. & Belfaitah, A. (2010). Acta Cryst. E66, o693.]). For radical bromination, see: Kikichi et al. (1998[Kikichi, D., Sakaguchi, S. & Ishii, Y. (1998). J. Org. Chem. 63, 6023-6026.]); Xu et al. (2003[Xu, F., Savary, K., Williams, J. M., Grabowski, E. J. J. & Reider, P. J. (2003). Tetrahedron Lett. 44, 1283-1286.]); Djerassi (1948[Djerassi, C. (1948). Chem. Rev. 43, 271-317.]); Newman & Lee (1972[Newman, M. S. & Lee, L. F. (1972). J. Org. Chem. 37, 4468-4469.]). For radical bromination of ketone and acetal functions, see: Marvell & Joncich (1951[Marvell, E. N. & Joncich, M. J. (1951). J. Am. Chem. Soc. 73, 973-975.]); Markees (1958[Markees, D. G. (1958). J. Org. Chem. 23, 1490-1492.]).

[Scheme 1]

Experimental

Crystal data

  • C13H11BrClNO2

  • Mr = 328.59

  • Monoclinic, P 21 /n

  • a = 6.1740 (4) Å

  • b = 29.0515 (14) Å

  • c = 7.2875 (4) Å

  • β = 99.167 (3)°

  • V = 1290.42 (13) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 3.39 mm−1

  • T = 100 K

  • 0.45 × 0.38 × 0.11 mm
Data collection

  • Bruker APEXII diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2002[Sheldrick, G. M. (2002). SADABS. University of Göttingen, Germany.]) Tmin = 0.238, Tmax = 0.689

  • 11364 measured reflections

  • 2938 independent reflections

  • 2430 reflections with I > 2σ(I)

  • Rint = 0.054
Refinement

  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.092

  • S = 1.02

  • 2938 reflections

  • 164 parameters

  • H-atom parameters constrained

  • Δρmax = 0.74 e Å−3

  • Δρmin = −0.85 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C13—H13B⋯O1i 0.97 2.41 3.347 (4) 162
Symmetry code: (i) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2001[Bruker (2001). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2001[Bruker (2001). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SIR2002 (Burla et al., 2005[Burla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G. L., De Caro, L., Giacovazzo, C., Polidori, G. & Spagna, R. (2005). J. Appl. Cryst. 38, 381-388.]); 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, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and DIAMOND (Brandenburg & Berndt, 2001[Brandenburg, K. & Berndt, M. (2001). DIAMOND. Crystal Impact, Bonn, Germany.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810010160/bq2201sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810010160/bq2201Isup2.hkl

checkCIF report


Comment top

Benzylic bromination can be carried out using N-bromosuccinimide (NBS) under photocatalytic conditions (Djerassi, 1948; Newman et al., 1972). It is also known that NBS react with benzaldehyde diethylacetal to give corresponding ester (Marvell et al., 1951; Markees et al., 1958). Although extensive studies have been carried out in the past, selectivity clearly remains a common problem in radical bromination (Kikichi et al., 1998; Xu et al., 2003). In previous works, we have reported structure determination of some new quinoline derivatives (Benzerka et al., 2008; Ladraa et al., 2009; Ladraa et al., 2010). In this paper, we report the synthesis and structure determination of new compound, resulting from the radical bromination of 2-chloro-3-(1,3-dioxolan-2-yl)-6-methylquinoline, (I), under photocatalytic conditions. Our attempt to brominate the methyl group linked at C-6 position of quinoline ring, which has an acetal function at C-3, was failed and led to the 2-bromoethyl 2-chloro-6-methylquinoline-3-carboxylate (I). This compound is the result of the unwanted conversion of the acetal to the corresponding ester.

The molecular geometry and the atom-numbering scheme of (I) are shown in Figure 1. The asymmetric unit of title molecule contains a 2-bromoethylcarboxylate group linked to quinolyl moiety. The two rings of quinolyl moiety are fused in an axial fashion and form a dihedral angle of 1.28 (9)° The crystal structure can be described as layers in zig zag along of c-axis which quinoline rings are parallel to the (110) plane. The crystal packing is stabilized by weak hydrogen bonds [C—H···O] and intermolecular interactions between Br and O atoms [Br···O= 3.076 (2)] (Figure 2), resulting in the formation of a three dimensional network and reinforcing a cohesion of structure. Hydrogen-bonding parameters are listed in Table 1.

Related literature top

For our previous work on the preparation of quinoline derivatives, see: Benzerka et al. (2008); Ladraa et al. (2009, 2010). For radical bromination, see: Kikichi et al. (1998); Xu et al. (2003); Djerassi (1948); Newman et al. (1972). For radical bromination of ketone and acetal functions, see: Marvell et al. (1951); Markees et al. (1958).

Experimental top

The title compound (I) was synthesized by treating 1 mmol. of 2-chloro-3-(1,3-dioxolan-2-yl)-6-methylquinoline with 1 mmol. of N-bromosuccinimide in the presence of 0.5 mmol. of dibenzoylperoxide in CCl4 under photocatalytic conditions. The contents were then cooled and filtered off and the filtrate was concentrated under reduced pressure. The residue was subjected to column chromatography (silica gel, eluent: CH2Cl2) to afford pure product. Crystals suitable for x-ray analysis were obtained by slow evaporation of a dichloromethane solution of (I).

Refinement top

All H atoms were localized on Fourier maps but introduced in calculated positions and treated as riding on their parent C atom. (with C—H = 0.93Å, 0.96Å, 0.97Å and Uiso(H) =1.2 or 1.5(carrier atom)).

Computing details top

Data collection: APEX2 (Bruker, 2001); cell refinement: SMART (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SIR2002 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and DIAMOND (Brandenburg & Berndt, 2001); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. (Farrugia, 1997) the structure of the title compound with the atomic labelling scheme. Displacement are drawn at the 50% probability level.
[Figure 2] Fig. 2. (Brandenburg & Berndt, 2001) Part of crystal packing of (I) showing hydrogen bond [C—H···O] and short interaction [Br···O]as dashed line.
[Figure 3] Fig. 3. The formation of the title compound.
2-Bromoethyl 2-chloro-6-methylquinoline-3-carboxylate top
Crystal data top
C13H11BrClNO2F(000) = 656
Mr = 328.59Dx = 1.691 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
a = 6.1740 (4) ÅCell parameters from 3765 reflections
b = 29.0515 (14) Åθ = 2.8–27.3°
c = 7.2875 (4) ŵ = 3.39 mm−1
β = 99.167 (3)°T = 100 K
V = 1290.42 (13) Å3Prism, colourless
Z = 40.45 × 0.38 × 0.11 mm
Data collection top
Bruker APEXII
diffractometer		2938 independent reflections
Radiation source: Enraf–Nonius FR5902430 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.054
CCD rotation images, thick slices scansθmax = 27.5°, θmin = 2.8°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2002)		h = −7→7
Tmin = 0.238, Tmax = 0.689k = −37→37
11364 measured reflectionsl = −9→9
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.092H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0397P)2 + 1.2764P]
where P = (Fo2 + 2Fc2)/3
2938 reflections(Δ/σ)max = 0.001
164 parametersΔρmax = 0.74 e Å−3
0 restraintsΔρmin = −0.85 e Å−3
Crystal data top
C13H11BrClNO2V = 1290.42 (13) Å3
Mr = 328.59Z = 4
Monoclinic, P21/nMo Kα radiation
a = 6.1740 (4) ŵ = 3.39 mm−1
b = 29.0515 (14) ÅT = 100 K
c = 7.2875 (4) Å0.45 × 0.38 × 0.11 mm
β = 99.167 (3)°
Data collection top
Bruker APEXII
diffractometer		2938 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2002)		2430 reflections with I > 2σ(I)
Tmin = 0.238, Tmax = 0.689Rint = 0.054
11364 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0370 restraints
wR(F2) = 0.092H-atom parameters constrained
S = 1.02Δρmax = 0.74 e Å−3
2938 reflectionsΔρmin = −0.85 e Å−3
164 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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
C10.7808 (4)0.08966 (9)0.2084 (4)0.0164 (5)
C21.0027 (4)0.10023 (8)0.2862 (4)0.0152 (5)
C31.1423 (4)0.06355 (9)0.3242 (4)0.0151 (5)
H31.28740.06870.37750.018*
C41.0694 (4)0.01828 (9)0.2837 (4)0.0147 (5)
C51.2083 (4)−0.02083 (9)0.3149 (4)0.0167 (6)
H51.3551−0.01690.36570.02*
C61.1299 (4)−0.06439 (9)0.2713 (4)0.0161 (5)
C70.9057 (5)−0.06973 (9)0.1919 (4)0.0180 (6)
H70.8517−0.09910.16160.022*
C80.7665 (4)−0.03275 (9)0.1586 (4)0.0181 (6)
H80.6206−0.03710.10570.022*
C90.8464 (4)0.01207 (9)0.2053 (4)0.0147 (5)
C101.2752 (5)−0.10631 (9)0.3046 (4)0.0204 (6)
H10A1.425−0.09680.33940.031*
H10B1.2613−0.12440.1930.031*
H10C1.2317−0.12440.40270.031*
C111.0855 (4)0.14836 (9)0.3158 (4)0.0188 (6)
C121.3409 (5)0.19567 (9)0.5055 (5)0.0263 (7)
H12A1.37360.20750.38850.032*
H12B1.47880.19150.58830.032*
C131.2040 (5)0.23018 (9)0.5886 (5)0.0247 (7)
H13A1.0650.23420.5070.03*
H13B1.27890.25960.60020.03*
N10.7035 (4)0.04864 (7)0.1709 (3)0.0164 (5)
O11.0343 (4)0.17987 (7)0.2112 (3)0.0292 (5)
O21.2320 (3)0.15146 (6)0.4733 (3)0.0199 (4)
Cl10.58811 (11)0.13419 (2)0.16345 (10)0.02179 (17)
Br11.15019 (5)0.209908 (9)0.83386 (5)0.02814 (11)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0161 (13)0.0178 (12)0.0153 (13)0.0059 (10)0.0026 (11)0.0012 (11)
C20.0163 (13)0.0125 (11)0.0176 (13)−0.0006 (9)0.0050 (11)−0.0013 (10)
C30.0117 (12)0.0159 (12)0.0180 (13)0.0001 (9)0.0030 (11)0.0004 (11)
C40.0134 (12)0.0140 (11)0.0169 (13)−0.0012 (9)0.0035 (11)0.0000 (10)
C50.0124 (12)0.0174 (12)0.0200 (14)0.0012 (10)0.0018 (11)−0.0007 (11)
C60.0177 (13)0.0160 (12)0.0150 (13)0.0031 (9)0.0039 (11)0.0005 (11)
C70.0207 (14)0.0130 (12)0.0198 (14)−0.0013 (10)0.0019 (12)−0.0006 (11)
C80.0151 (13)0.0179 (12)0.0202 (14)−0.0014 (10)−0.0004 (11)−0.0036 (11)
C90.0147 (13)0.0142 (12)0.0151 (13)0.0016 (9)0.0017 (11)0.0002 (10)
C100.0207 (14)0.0147 (12)0.0261 (16)0.0042 (10)0.0045 (12)−0.0006 (11)
C110.0169 (13)0.0144 (12)0.0281 (16)0.0005 (10)0.0123 (12)−0.0014 (12)
C120.0254 (15)0.0119 (12)0.043 (2)−0.0056 (11)0.0098 (14)−0.0054 (13)
C130.0291 (16)0.0125 (12)0.0335 (18)−0.0003 (11)0.0079 (14)−0.0005 (12)
N10.0133 (11)0.0173 (10)0.0179 (12)0.0036 (8)0.0005 (9)−0.0005 (10)
O10.0349 (12)0.0158 (9)0.0376 (13)0.0016 (8)0.0084 (11)0.0066 (10)
O20.0208 (10)0.0117 (8)0.0280 (11)−0.0022 (7)0.0062 (9)−0.0040 (8)
Cl10.0196 (3)0.0190 (3)0.0273 (4)0.0092 (2)0.0050 (3)0.0016 (3)
Br10.03431 (19)0.01765 (15)0.0334 (2)0.00054 (11)0.00824 (14)−0.00443 (13)
Geometric parameters (Å, º) top
C1—N11.296 (3)C8—C91.415 (3)
C1—C21.430 (4)C8—H80.93
C1—Cl11.753 (3)C9—N11.378 (3)
C2—C31.371 (3)C10—H10A0.96
C2—C111.493 (3)C10—H10B0.96
C3—C41.406 (3)C10—H10C0.96
C3—H30.93C11—O11.201 (3)
C4—C91.416 (4)C11—O21.346 (3)
C4—C51.420 (3)C12—O21.451 (3)
C5—C61.374 (4)C12—C131.500 (4)
C5—H50.93C12—H12A0.97
C6—C71.422 (4)C12—H12B0.97
C6—C101.509 (3)C13—Br11.960 (3)
C7—C81.373 (4)C13—H13A0.97
C7—H70.93C13—H13B0.97
N1—C1—C2125.3 (2)N1—C9—C4121.9 (2)
N1—C1—Cl1115.0 (2)C8—C9—C4119.6 (2)
C2—C1—Cl1119.6 (2)C6—C10—H10A109.5
C3—C2—C1116.4 (2)C6—C10—H10B109.5
C3—C2—C11120.6 (2)H10A—C10—H10B109.5
C1—C2—C11122.9 (2)C6—C10—H10C109.5
C2—C3—C4121.0 (2)H10A—C10—H10C109.5
C2—C3—H3119.5H10B—C10—H10C109.5
C4—C3—H3119.5O1—C11—O2124.3 (2)
C3—C4—C9117.5 (2)O1—C11—C2125.0 (3)
C3—C4—C5123.4 (2)O2—C11—C2110.7 (2)
C9—C4—C5119.1 (2)O2—C12—C13112.4 (2)
C6—C5—C4121.2 (2)O2—C12—H12A109.1
C6—C5—H5119.4C13—C12—H12A109.1
C4—C5—H5119.4O2—C12—H12B109.1
C5—C6—C7118.6 (2)C13—C12—H12B109.1
C5—C6—C10121.9 (2)H12A—C12—H12B107.9
C7—C6—C10119.5 (2)C12—C13—Br1110.8 (2)
C8—C7—C6121.9 (2)C12—C13—H13A109.5
C8—C7—H7119.1Br1—C13—H13A109.5
C6—C7—H7119.1C12—C13—H13B109.5
C7—C8—C9119.5 (2)Br1—C13—H13B109.5
C7—C8—H8120.2H13A—C13—H13B108.1
C9—C8—H8120.2C1—N1—C9117.9 (2)
N1—C9—C8118.5 (2)C11—O2—C12115.3 (2)
N1—C1—C2—C3−0.3 (4)C3—C4—C9—N1−0.6 (4)
Cl1—C1—C2—C3177.6 (2)C5—C4—C9—N1−179.7 (3)
N1—C1—C2—C11176.2 (3)C3—C4—C9—C8178.7 (3)
Cl1—C1—C2—C11−5.9 (4)C5—C4—C9—C8−0.4 (4)
C1—C2—C3—C41.4 (4)C3—C2—C11—O1137.8 (3)
C11—C2—C3—C4−175.2 (3)C1—C2—C11—O1−38.6 (4)
C2—C3—C4—C9−1.0 (4)C3—C2—C11—O2−40.1 (4)
C2—C3—C4—C5178.1 (3)C1—C2—C11—O2143.5 (3)
C3—C4—C5—C6−179.3 (3)O2—C12—C13—Br162.8 (3)
C9—C4—C5—C6−0.3 (4)C2—C1—N1—C9−1.2 (4)
C4—C5—C6—C70.6 (4)Cl1—C1—N1—C9−179.2 (2)
C4—C5—C6—C10−179.6 (3)C8—C9—N1—C1−177.6 (3)
C5—C6—C7—C8−0.3 (4)C4—C9—N1—C11.7 (4)
C10—C6—C7—C8−180.0 (3)O1—C11—O2—C12−4.3 (4)
C6—C7—C8—C9−0.4 (4)C2—C11—O2—C12173.6 (2)
C7—C8—C9—N1−179.9 (3)C13—C12—O2—C1181.8 (3)
C7—C8—C9—C40.8 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13B···O1i0.972.413.347 (4)162
Symmetry code: (i) x+1/2, −y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC13H11BrClNO2
Mr328.59
Crystal system, space groupMonoclinic, P21/n
Temperature (K)100
a, b, c (Å)6.1740 (4), 29.0515 (14), 7.2875 (4)
β (°) 99.167 (3)
V (Å3)1290.42 (13)
Z4
Radiation typeMo Kα
µ (mm−1)3.39
Crystal size (mm)0.45 × 0.38 × 0.11
Data collection
DiffractometerBruker APEXII
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2002)
Tmin, Tmax0.238, 0.689
No. of measured, independent and
observed [I > 2σ(I)] reflections		11364, 2938, 2430
Rint0.054
(sin θ/λ)max (Å−1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.092, 1.02
No. of reflections2938
No. of parameters164
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.74, −0.85

Computer programs: APEX2 (Bruker, 2001), SMART (Bruker, 2001), SAINT (Bruker, 2001), SIR2002 (Burla et al., 2005), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and DIAMOND (Brandenburg & Berndt, 2001), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13B···O1i0.97002.41003.347 (4)162.00
Symmetry code: (i) x+1/2, −y+1/2, z+1/2.
 

Acknowledgements

We are grateful to all personnel at the PHYSYNOR Laboratory, Université Mentouri-Constantine, for their assistance. Thanks are due to MESRS (Ministére de l'Enseignement Supérieur et de la Recherche Scientifique - Algérie) for financial support.

References

First citationBenzerka, S., Bouraiou, A., Bouacida, S., Rhouati, S. & Belfaitah, A. (2008). Acta Cryst. E64, o2089–o2090.  Web of Science CSD CrossRef IUCr Journals Google Scholar
 First citationBrandenburg, K. & Berndt, M. (2001). DIAMOND. Crystal Impact, Bonn, Germany.  Google Scholar
 First citationBruker (2001). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationBurla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G. L., De Caro, L., Giacovazzo, C., Polidori, G. & Spagna, R. (2005). J. Appl. Cryst. 38, 381–388.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationDjerassi, C. (1948). Chem. Rev. 43, 271–317.  CrossRef PubMed CAS Web of Science Google Scholar
 First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
 First citationFarrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838.  CrossRef CAS IUCr Journals Google Scholar
 First citationKikichi, D., Sakaguchi, S. & Ishii, Y. (1998). J. Org. Chem. 63, 6023–6026.  PubMed Google Scholar
 First citationLadraa, S., Bouraiou, A., Bouacida, S., Roisnel, T. & Belfaitah, A. (2009). Acta Cryst. C65, o475–o478.  Web of Science CSD CrossRef IUCr Journals Google Scholar
 First citationLadraa, S., Bouraiou, A., Bouacida, S., Roisnel, T. & Belfaitah, A. (2010). Acta Cryst. E66, o693.  Web of Science CSD CrossRef IUCr Journals Google Scholar
 First citationMarkees, D. G. (1958). J. Org. Chem. 23, 1490–1492.  CrossRef CAS Web of Science Google Scholar
 First citationMarvell, E. N. & Joncich, M. J. (1951). J. Am. Chem. Soc. 73, 973–975.  CrossRef CAS Web of Science Google Scholar
 First citationNewman, M. S. & Lee, L. F. (1972). J. Org. Chem. 37, 4468–4469.  CrossRef CAS Web of Science Google Scholar
 First citationSheldrick, G. M. (2002). SADABS. University of Göttingen, Germany.  Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationXu, F., Savary, K., Williams, J. M., Grabowski, E. J. J. & Reider, P. J. (2003). Tetrahedron Lett. 44, 1283–1286.  Web of Science CrossRef CAS Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 66| Part 4| April 2010| Page o1006
doi:10.1107/S1600536810010160
Follow Acta Cryst. E
Sign up for e-alerts
E-alerts
Follow Acta Cryst. on Twitter
Twitter
Follow us on facebook
Facebook
Sign up for RSS feeds
RSS