supplementary materials


jj2174 scheme

Acta Cryst. (2013). E69, o1508-o1509    [ doi:10.1107/S1600536813024355 ]

1,5-Bis(4-chlorophenyl)-3-(4-methylphenyl)pentane-1,5-dione

R. Chithiravel, A. Thiruvalluvar, S. Muthusubramanian and R. J. Butcher

Abstract top

In the title molecule, C24H20Cl2O2, the central methylbenzene ring forms dihedral angles of 42.47 (10) and 34.34 (10)° with the terminal 4-chlorophenyl fragments. The dihedral angle between the chlorobenzene rings is 34.45 (11)°. A weak intramolecular C-H...O interaction generates an S(6) ring motif. The crystal packing exhibits weak C-H...O hydrogen bonds and C-H...[pi] interactions.

Comment top

A simplified green chemistry approach to the Michael-addition reaction using the "Grindstone Chemistry" method for conducting exothermic reactions in the solvent-free mode has been described (Yang et al. 2005). We tested energy saving procedures developed in our laboratory for the preparation of 1,5-diketones starting from fragrant aldehydes and fragrant ketones in the presence of NaOH under solvent-free conditions. Using this method, we obtained the title compound, (I) (Fig. 1). The synthesis of many heterocyclic compounds (Hirsch & Bailey, 1978) form an important synthetic intermediate compounds of 1,5-Diketones. Further, compared to existing methods, the main advantages of the present procedure is fast reaction times, solvent-free, mild, simple, moderately high yields and no side product formation.

The structures of related compounds viz., 3-(2-Chlorophenyl)-1,5-bis(4-nitrophenyl)pentane-1,5-dione (Qiu et al. 2006), 1,5-Bis(4-chlorophenyl)-3- (2-chloroquinolin-3-yl)pentane-1,5-dione (Insuasty et al. 2006), 3-(2-Chlorophenyl)-1,5-bis(4-chlorophenyl)pentane-1,5-dione (Jasinski et al. 2007), 1,5-Bis(4-chlorophenyl)-3-(2-thienyl)pentane-1,5-dione (Huang et al. 2008), 1,5-Bis(4-chlorophenyl)-3-[4-(dimethylamino)phenyl]pentane-1,5-dione (Lei & Bai, 2009), 3-(3-Bromo-4-methoxyphenyl)-1,5-diphenylpentane-1,5-dione (Dutkiewicz et al. 2010) and 1,5-Bis(thiophen-2-yl)-3-(2,4,5-trimethoxyphenyl) pentane-1,5-dione (Fun et al. 2011) have been reported. Many promising applications from linear π-conjugated organic molecules and polymers have attracted considerable interest for organic light-emitting diodes, non-linear optical properties, conductivity, photocells, field effect transistors, and so on due to their delocalized π systems (Burroughes et al., 1990; Smith et al., 2005; Li et al., 2004; Sariciftci et al., 1992). A new title compound was synthesized and the crystal structure is reported here.

In the title molecule, C24H20Cl2O2, (Fig. 1), the pentane-1,5-dione unit (C1—C5/O1/O5) is puckered with the torsion angles C1—C2—C3—C4 = 72.49 (19)° and C2—C3—C4—C5 = -179.02 (16)°, making the two ketone groups pointing towards opposite directions. The central methylbenzene ring forms dihedral angles of 42.47 (10) and 34.34 (10)° with the two terminal 4-chlorophenyl fragments. The dihedral angle between the two chlorobenzene rings is 34.45 (11)°. A weak intramolecular C4—H4A···O1 interaction (Table 1) which generates an S(6) ring motif (Bernstein et al., 1995) helps to stabilize this conformation. The crystal packing exhibits weak intermolecular C16—H16···O5 hydrogen bonded C(9) chains (Bernstein et al., 1995) and C55—H55···π interactions involving (C31—C36) methylbenzene ring (Table 1, Fig. 2 & Fig. 3). The C—C, Car—Car, C—Cl and C=O bond lengths in (I) are within their normal ranges (Allen et al., 1987).

Related literature top

For the synthesis of 1,5-diketones, see: Yang et al. (2005); Hirsch & Bailey (1978). For the crystal structures of related compounds, see: Qiu et al. (2006); Insuasty et al. (2006); Jasinski et al. (2007); Huang et al. (2008); Lei & Bai (2009); Dutkiewicz et al. (2010); Fun et al. (2011). For the applications of delocalized π-systems, see: Burroughes et al. (1990); Smith et al. (2005); Li et al. (2004); Sariciftci et al. (1992). For hydrogen-bond motifs, see: Bernstein et al. (1995). For bond-length data, see: Allen et al. (1987).

Experimental top

The title compound was synthesized according to a modified solvent-free greener approach method (Yang et al., 2005). 4-Chloroacetophenone (0.5 g, 3 mmol), 1-(4-chlorophenyl)-3-(4-methylpenyl)prop-2-ene-1-one (0.8 g, 4 mmol) and commercial powdered NaOH (0.06 g, 1.5 mmol) were crushed together for 20 mt s, using a pestle and mortar. Recystallization from methanol gave colourless crystals. Yield: 1.1 g (90%).

Refinement top

All H-atoms were positioned geometrically and allowed to ride on their parent atoms, with C—H = 0.93 (aromatic), 0.97 (methylene group) and 0.98 Å (methine), with Uiso(H) = 1.2Ueq(C); 0.96 Å, Uiso(H) = 1.5Ueq(C) for methyl group.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis PRO (Agilent, 2012); program(s) used to solve structure: DIRDIF2008 (Beurskens et al., 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL2013 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level. H atoms are shown as small spheres of arbitrary radius. The dashed line indicates a weak C—H···O intramolecular hydrogen bond.
[Figure 2] Fig. 2. The partial packing of the title compound, viewed along the b axis. Dashed lines indicate hydrogen-bonded C(9) chains along the c axis. H atoms not involved in hydrogen bonding have been omitted for clarity.
[Figure 3] Fig. 3. Crystal structure of the title compound, showing the formation of a C—H···π interaction. Symmetry code (ii): x, y + 1, z.
1,5-Bis(4-chlorophenyl)-3-(4-methylphenyl)pentane-1,5-dione top
Crystal data top
C24H20Cl2O2F(000) = 856
Mr = 411.30Dx = 1.285 Mg m3
Monoclinic, P21/cMelting point: 327(2) K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 18.6794 (11) ÅCell parameters from 5569 reflections
b = 7.5477 (4) Åθ = 3.3–75.4°
c = 15.5196 (8) ŵ = 0.32 mm1
β = 103.622 (5)°T = 296 K
V = 2126.5 (2) Å3Prism, colourless
Z = 40.51 × 0.42 × 0.37 mm
Data collection top
Agilent Xcalibur Ruby Gemini
diffractometer
4341 independent reflections
Radiation source: Enhance (Cu) X-ray Source3735 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
Detector resolution: 10.5081 pixels mm-1θmax = 26.5°, θmin = 2.2°
ω scansh = 2321
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2012)
k = 98
Tmin = 0.443, Tmax = 1.000l = 1915
14252 measured reflections
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.050 w = 1/[σ2(Fo2) + (0.0627P)2 + 0.5487P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.146(Δ/σ)max = 0.001
S = 1.07Δρmax = 0.33 e Å3
4341 reflectionsΔρmin = 0.37 e Å3
255 parametersExtinction correction: SHELXL2013 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.0227 (17)
Crystal data top
C24H20Cl2O2V = 2126.5 (2) Å3
Mr = 411.30Z = 4
Monoclinic, P21/cMo Kα radiation
a = 18.6794 (11) ŵ = 0.32 mm1
b = 7.5477 (4) ÅT = 296 K
c = 15.5196 (8) Å0.51 × 0.42 × 0.37 mm
β = 103.622 (5)°
Data collection top
Agilent Xcalibur Ruby Gemini
diffractometer
4341 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2012)
3735 reflections with I > 2σ(I)
Tmin = 0.443, Tmax = 1.000Rint = 0.024
14252 measured reflectionsθmax = 26.5°
Refinement top
R[F2 > 2σ(F2)] = 0.050H-atom parameters constrained
wR(F2) = 0.146Δρmax = 0.33 e Å3
S = 1.07Δρmin = 0.37 e Å3
4341 reflectionsAbsolute structure: ?
255 parametersAbsolute structure parameter: ?
0 restraintsRogers parameter: ?
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

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl140.50733 (5)0.76817 (14)0.95387 (6)0.1283 (4)
Cl540.08862 (5)1.03187 (11)0.11762 (5)0.1154 (3)
O10.32422 (10)0.76750 (19)0.53035 (12)0.0873 (6)
O50.27979 (11)0.3043 (2)0.26076 (12)0.0939 (7)
C10.32982 (10)0.6468 (3)0.58359 (14)0.0638 (6)
C20.29189 (10)0.4711 (2)0.55773 (13)0.0621 (6)
C30.25188 (9)0.4591 (2)0.46011 (12)0.0555 (5)
C40.30797 (10)0.4435 (3)0.40126 (13)0.0647 (6)
C50.27264 (11)0.4342 (3)0.30405 (14)0.0644 (6)
C110.37394 (9)0.6711 (3)0.67653 (14)0.0626 (6)
C120.40855 (12)0.8328 (3)0.70082 (17)0.0809 (8)
C130.44906 (13)0.8624 (4)0.7860 (2)0.0933 (10)
C140.45523 (12)0.7294 (4)0.84725 (17)0.0838 (9)
C150.42146 (13)0.5692 (3)0.82660 (16)0.0813 (8)
C160.38072 (11)0.5404 (3)0.74081 (14)0.0705 (7)
C310.19689 (9)0.3081 (2)0.44168 (11)0.0525 (5)
C320.21576 (10)0.1365 (2)0.46994 (12)0.0596 (5)
C330.16507 (11)0.0008 (3)0.45037 (13)0.0649 (6)
C340.09424 (12)0.0296 (3)0.40097 (13)0.0676 (6)
C350.07564 (11)0.1993 (3)0.37249 (15)0.0754 (7)
C360.12561 (10)0.3367 (3)0.39251 (14)0.0668 (6)
C370.04025 (16)0.1219 (4)0.3772 (2)0.1036 (10)
C510.22673 (10)0.5860 (2)0.25994 (12)0.0591 (6)
C520.17530 (13)0.5558 (3)0.18151 (14)0.0766 (8)
C530.13217 (14)0.6916 (4)0.13849 (15)0.0844 (9)
C540.14217 (13)0.8596 (3)0.17322 (14)0.0739 (7)
C550.19288 (12)0.8948 (3)0.25063 (14)0.0701 (7)
C560.23502 (11)0.7562 (2)0.29495 (13)0.0619 (6)
H2A0.256630.451280.593690.0745*
H2B0.328340.377350.570950.0745*
H30.224500.569780.444280.0666*
H4A0.340750.544920.412210.0776*
H4B0.337580.338000.418300.0776*
H120.404250.922550.658850.0970*
H130.471880.971080.801590.1118*
H150.425730.481070.869370.0975*
H160.357580.431740.726120.0846*
H320.263270.112480.502550.0714*
H330.178900.112850.470920.0778*
H350.028340.222200.338960.0905*
H360.111200.450410.372670.0802*
H37A0.014570.137650.423420.1553*
H37B0.066420.228510.370490.1553*
H37C0.005480.095580.322500.1553*
H520.169760.442290.157490.0920*
H530.096670.669940.086530.1012*
H550.199021.009420.273140.0842*
H560.268920.777540.348280.0742*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl140.1032 (5)0.1647 (9)0.1004 (5)0.0240 (5)0.0091 (4)0.0387 (5)
Cl540.1193 (6)0.1104 (6)0.1139 (6)0.0419 (4)0.0225 (4)0.0407 (4)
O10.0932 (11)0.0590 (8)0.0993 (11)0.0099 (8)0.0019 (9)0.0133 (8)
O50.1211 (14)0.0656 (9)0.1022 (12)0.0217 (9)0.0405 (11)0.0103 (8)
C10.0529 (9)0.0552 (10)0.0820 (12)0.0002 (8)0.0131 (8)0.0033 (9)
C20.0566 (10)0.0565 (10)0.0712 (11)0.0045 (8)0.0112 (8)0.0022 (8)
C30.0497 (8)0.0505 (9)0.0668 (10)0.0040 (7)0.0150 (7)0.0062 (7)
C40.0532 (9)0.0616 (10)0.0823 (12)0.0055 (8)0.0222 (9)0.0091 (9)
C50.0671 (11)0.0552 (10)0.0787 (12)0.0025 (8)0.0326 (9)0.0011 (9)
C110.0463 (9)0.0605 (10)0.0822 (12)0.0050 (8)0.0174 (8)0.0064 (9)
C120.0711 (13)0.0719 (13)0.1003 (16)0.0206 (10)0.0214 (11)0.0078 (12)
C130.0734 (14)0.0910 (17)0.115 (2)0.0313 (13)0.0215 (13)0.0300 (15)
C140.0568 (11)0.1059 (18)0.0862 (15)0.0097 (11)0.0121 (10)0.0243 (14)
C150.0712 (13)0.0886 (15)0.0796 (14)0.0029 (11)0.0088 (10)0.0025 (12)
C160.0611 (11)0.0675 (12)0.0801 (13)0.0088 (9)0.0109 (9)0.0048 (10)
C310.0515 (8)0.0530 (9)0.0538 (9)0.0018 (7)0.0142 (7)0.0021 (7)
C320.0578 (9)0.0564 (9)0.0618 (10)0.0035 (8)0.0088 (7)0.0024 (8)
C330.0763 (12)0.0512 (9)0.0673 (11)0.0017 (8)0.0174 (9)0.0012 (8)
C340.0693 (11)0.0680 (11)0.0656 (11)0.0139 (9)0.0161 (9)0.0065 (9)
C350.0532 (10)0.0831 (14)0.0836 (14)0.0055 (10)0.0034 (9)0.0072 (11)
C360.0554 (10)0.0615 (10)0.0802 (12)0.0041 (8)0.0094 (9)0.0126 (9)
C370.0965 (18)0.0865 (16)0.120 (2)0.0326 (15)0.0096 (15)0.0107 (15)
C510.0632 (10)0.0577 (10)0.0627 (10)0.0011 (8)0.0274 (8)0.0007 (8)
C520.0894 (15)0.0721 (13)0.0706 (12)0.0036 (11)0.0232 (11)0.0134 (10)
C530.0842 (15)0.1014 (17)0.0645 (12)0.0120 (13)0.0116 (10)0.0041 (12)
C540.0799 (13)0.0783 (13)0.0691 (12)0.0179 (11)0.0291 (10)0.0167 (10)
C550.0856 (13)0.0558 (10)0.0752 (12)0.0018 (9)0.0313 (10)0.0071 (9)
C560.0692 (11)0.0561 (10)0.0632 (10)0.0044 (8)0.0214 (8)0.0026 (8)
Geometric parameters (Å, º) top
Cl14—C141.736 (3)C51—C561.389 (2)
Cl54—C541.741 (2)C52—C531.376 (4)
O1—C11.218 (3)C53—C541.373 (4)
O5—C51.214 (3)C54—C551.369 (3)
C1—C21.513 (3)C55—C561.390 (3)
C1—C111.495 (3)C2—H2A0.9700
C2—C31.526 (3)C2—H2B0.9700
C3—C41.548 (3)C3—H30.9800
C3—C311.516 (2)C4—H4A0.9700
C4—C51.499 (3)C4—H4B0.9700
C5—C511.497 (3)C12—H120.9300
C11—C121.391 (3)C13—H130.9300
C11—C161.387 (3)C15—H150.9300
C12—C131.378 (4)C16—H160.9300
C13—C141.369 (4)C32—H320.9300
C14—C151.367 (4)C33—H330.9300
C15—C161.386 (3)C35—H350.9300
C31—C321.386 (2)C36—H360.9300
C31—C361.387 (3)C37—H37A0.9600
C32—C331.379 (3)C37—H37B0.9600
C33—C341.381 (3)C37—H37C0.9600
C34—C351.373 (3)C52—H520.9300
C34—C371.512 (4)C53—H530.9300
C35—C361.381 (3)C55—H550.9300
C51—C521.381 (3)C56—H560.9300
O1—C1—C2121.06 (19)C1—C2—H2B109.00
O1—C1—C11120.2 (2)C3—C2—H2A109.00
C2—C1—C11118.76 (18)C3—C2—H2B109.00
C1—C2—C3113.88 (15)H2A—C2—H2B108.00
C2—C3—C4110.43 (15)C2—C3—H3108.00
C2—C3—C31112.56 (14)C4—C3—H3108.00
C4—C3—C31110.75 (14)C31—C3—H3108.00
C3—C4—C5113.49 (16)C3—C4—H4A109.00
O5—C5—C4121.0 (2)C3—C4—H4B109.00
O5—C5—C51119.42 (19)C5—C4—H4A109.00
C4—C5—C51119.57 (18)C5—C4—H4B109.00
C1—C11—C12119.0 (2)H4A—C4—H4B108.00
C1—C11—C16122.9 (2)C11—C12—H12119.00
C12—C11—C16118.1 (2)C13—C12—H12119.00
C11—C12—C13121.2 (2)C12—C13—H13120.00
C12—C13—C14119.0 (3)C14—C13—H13121.00
Cl14—C14—C13118.4 (2)C14—C15—H15121.00
Cl14—C14—C15119.8 (2)C16—C15—H15121.00
C13—C14—C15121.8 (2)C11—C16—H16119.00
C14—C15—C16118.9 (2)C15—C16—H16119.00
C11—C16—C15121.0 (2)C31—C32—H32120.00
C3—C31—C32122.17 (15)C33—C32—H32120.00
C3—C31—C36120.46 (15)C32—C33—H33119.00
C32—C31—C36117.34 (17)C34—C33—H33119.00
C31—C32—C33120.93 (18)C34—C35—H35119.00
C32—C33—C34121.6 (2)C36—C35—H35119.00
C33—C34—C35117.5 (2)C31—C36—H36119.00
C33—C34—C37120.9 (2)C35—C36—H36119.00
C35—C34—C37121.6 (2)C34—C37—H37A109.00
C34—C35—C36121.5 (2)C34—C37—H37B109.00
C31—C36—C35121.2 (2)C34—C37—H37C109.00
C5—C51—C52118.80 (17)H37A—C37—H37B110.00
C5—C51—C56122.00 (17)H37A—C37—H37C109.00
C52—C51—C56119.20 (17)H37B—C37—H37C109.00
C51—C52—C53120.8 (2)C51—C52—H52120.00
C52—C53—C54119.2 (2)C53—C52—H52120.00
Cl54—C54—C53119.08 (18)C52—C53—H53120.00
Cl54—C54—C55119.21 (18)C54—C53—H53120.00
C53—C54—C55121.7 (2)C54—C55—H55121.00
C54—C55—C56118.8 (2)C56—C55—H55121.00
C51—C56—C55120.30 (18)C51—C56—H56120.00
C1—C2—H2A109.00C55—C56—H56120.00
O1—C1—C2—C33.7 (3)C12—C13—C14—Cl14179.28 (19)
C11—C1—C2—C3177.04 (16)C12—C13—C14—C151.0 (4)
O1—C1—C11—C120.3 (3)Cl14—C14—C15—C16179.36 (18)
O1—C1—C11—C16178.2 (2)C13—C14—C15—C160.9 (4)
C2—C1—C11—C12179.59 (18)C14—C15—C16—C110.1 (3)
C2—C1—C11—C161.1 (3)C3—C31—C32—C33178.41 (17)
C1—C2—C3—C472.49 (19)C36—C31—C32—C330.6 (3)
C1—C2—C3—C31163.18 (15)C3—C31—C36—C35177.69 (18)
C2—C3—C4—C5179.02 (16)C32—C31—C36—C350.1 (3)
C31—C3—C4—C555.6 (2)C31—C32—C33—C341.0 (3)
C2—C3—C31—C3251.0 (2)C32—C33—C34—C350.6 (3)
C2—C3—C31—C36131.25 (18)C32—C33—C34—C37177.7 (2)
C4—C3—C31—C3273.1 (2)C33—C34—C35—C360.2 (3)
C4—C3—C31—C36104.60 (19)C37—C34—C35—C36178.4 (2)
C3—C4—C5—O5117.3 (2)C34—C35—C36—C310.5 (3)
C3—C4—C5—C5161.6 (2)C5—C51—C52—C53179.7 (2)
O5—C5—C51—C5220.8 (3)C56—C51—C52—C530.5 (3)
O5—C5—C51—C56158.4 (2)C5—C51—C56—C55178.05 (19)
C4—C5—C51—C52158.1 (2)C52—C51—C56—C551.1 (3)
C4—C5—C51—C5622.7 (3)C51—C52—C53—C541.8 (4)
C1—C11—C12—C13179.2 (2)C52—C53—C54—Cl54178.90 (19)
C16—C11—C12—C130.6 (3)C52—C53—C54—C551.4 (4)
C1—C11—C16—C15179.2 (2)Cl54—C54—C55—C56179.52 (17)
C12—C11—C16—C150.7 (3)C53—C54—C55—C560.1 (4)
C11—C12—C13—C140.2 (4)C54—C55—C56—C511.4 (3)
Hydrogen-bond geometry (Å, º) top
Cg2 is the centroid of the (C31-C36) methylbenzene ring.
D—H···AD—HH···AD···AD—H···A
C4—H4A···O10.972.563.130 (3)118
C16—H16···O5i0.932.443.270 (3)149
C55—H55···Cg2ii0.932.973.629 (2)129
Symmetry codes: (i) x, y+1/2, z+1/2; (ii) x, y+1, z.
Hydrogen-bond geometry (Å, º) top
Cg2 is the centroid of the (C31-C36) methylbenzene ring.
D—H···AD—HH···AD···AD—H···A
C4—H4A···O10.972.563.130 (3)118
C16—H16···O5i0.932.443.270 (3)149
C55—H55···Cg2ii0.932.973.629 (2)129
Symmetry codes: (i) x, y+1/2, z+1/2; (ii) x, y+1, z.
Acknowledgements top

RJB acknowledges the NSF–MRI program (grant No. CHE0619278) for funds to purchase the X-ray diffractometer.

references
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