5,8-Dibromo-15-nitro-2,11-dithia­[3.3]paracyclo­phane

Hu, F.; Chen, Z.-M.

doi:10.1107/S1600536811048434

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 67| Part 12| December 2011| Page o3368

https://doi.org/10.1107/S1600536811048434

Open

access

5,8-Dibromo-15-nitro-2,11-dithia[3.3]paracyclophane

Fang Hu ^a ^* and Zhi-Ming Chen ^a

^aKey Laboratory of Pesticide and Chemical Biology of the Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China
^*Correspondence e-mail: hufang5888@163.com

(Received 11 October 2011; accepted 15 November 2011; online 19 November 2011)

In the title compound [systematic name: 13,15-dibromo-6-nitro-3,10-dithiatricyclo[10.2.2.2^5,8]octadeca-1(14),5,7,12,15,17-hexaene], C₁₆H₁₃Br₂NO₂S₂, the dihedral angle between the two benzene rings is 0.93 (2)°. The crystal structure is stabilized by weak π–π intermolecular interactions [centroid–centroid distance = 3.286 (5) Å]. One S atom and the H atoms on neighboring C atoms are disordered over two sets of sites (occupancy ratios: S = 0.91:0.09 and H = 0.93:0.07).

Related literature

For industrial applications of paracyclophanes, see: Xu et al. (2008 ). For the preparation of the title compound, see: Wang et al. (2006 ).

Experimental

Crystal data

C₁₆H₁₃Br₂NO₂S₂
M_r = 475.21
Monoclinic, P 2₁ /n
a = 6.9200 (3) Å
b = 12.6556 (6) Å
c = 18.8743 (8) Å
β = 94.939 (2)°
V = 1646.81 (13) Å³
Z = 4
Mo Kα radiation
μ = 5.18 mm⁻¹
T = 298 K
0.20 × 0.10 × 0.10 mm

Data collection

Bruker SMART CCD area-detector diffractometer
11528 measured reflections
3885 independent reflections
2405 reflections with I > 2σ(I)
R_int = 0.046

Refinement

R[F² > 2σ(F²)] = 0.047
wR(F²) = 0.119
S = 0.99
3885 reflections
218 parameters
10 restraints
H-atom parameters constrained
Δρ_max = 0.68 e Å⁻³
Δρ_min = −0.34 e Å⁻³

Data collection: SMART (Bruker, 2001 ); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXS97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536811048434/jj2107sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811048434/jj2107Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536811048434/jj2107Isup3.cml

checkCIF report

Comment top

Molecular building blocks associated with para-cyclophanes are widely used in chiral catalysis, optoelectronic (NLO) materials, polymer chemistry, materials science, molecular electronics and organic solar cells (Xu et al. 2008). Crystallographic studies on these types of complexes are relatively sparse when compared to the volume of synthesis research carried out in these areas. Herein, we report the crystal structure of the title complex, (I).

In the title compound, C₁₆ H₁₃ Br₂N O₂ S₂, (I), the dihedral angle between the two benzene rings is 0.93 (2)° (Fig. 1). Crystal packing is stabilized by weak π—π intermolecular interactions (centroid-to-centroid distance = 3.286 (5) Å). The S2 atom ((0.91:0.09 for the major and minor components) and H15A, H15B (0.93) H15C, H15D (0.07), H16A, H16B (0.93), H16C, H16D (0.07) atoms are disordered over two sites.

Related literature top

For industrial applications of para-cyclophnes, see: Xu et al. (2008). For the preparation of the title compound, see: Wang et al. (2006).

Experimental top

A solution with equimolar amounts of 2,5-dibromo-1,4-bis(mercaptomethyl)benzene (3.26 g,10 mmol) and 1,4-dibromomethyl-2-nitrobenzene(3.10 g,10 mmol) in degassed THF (500 ml) was added dropwise under N₂ over 12 h to a refluxing solution of potassium carbonate (6.9 g,50 mmol) in EtOH(1.5L). After 2 h at the reflux temperature, the mixture was cooled and the solvent removed. The resulting residue was treated with CH₂Cl₂ (300 ml) and water (300 ml). The aqueous was extracted with CH₂Cl₂ three times. The combined organic layers were dried over Na₂SO₄. The solvent was removed, and the resulting solid was chromatographed on silica gel using CH₂Cl₂/petroleum ether (1:1, v/v) as eluent. Colourless single crystals of the title compound suitable for X-ray diffraction were obtained by slow evaporation of a dichloromethane/n-hexane(1:30) solution over a period of 5 days (Wang et al., 2006).

Structure description top

For industrial applications of para-cyclophnes, see: Xu et al. (2008). For the preparation of the title compound, see: Wang et al. (2006).

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXS97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top

Fig. 1. Molecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. Dashed lines indicate disorder in the S2 ((0.91:0.09), H15A, H15B (0.93) H15C, H15D (0.07), H16A, H16B (0.93), H16C, H16D (0.07) atoms disordered over two sites.

13,15-dibromo-6-nitro-3,10-dithiatricyclo[10.2.2.2^5,8]octadeca- 1(14),5,7,12,15,17-hexaene top

Crystal data top

C₁₆H₁₃Br₂NO₂S₂	F(000) = 936
M_r = 475.21	D_x = 1.917 Mg m⁻³ D_m = 1.917 Mg m⁻³ D_m measured by not measured
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 1981 reflections
a = 6.9200 (3) Å	θ = 2.7–23.5°
b = 12.6556 (6) Å	µ = 5.18 mm⁻¹
c = 18.8743 (8) Å	T = 298 K
β = 94.939 (2)°	Block, colorless
V = 1646.81 (13) Å³	0.20 × 0.10 × 0.10 mm
Z = 4

Data collection top

Bruker SMART CCD area-detector diffractometer	2405 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.046
Graphite monochromator	θ_max = 28.3°, θ_min = 1.9°
Detector resolution: 14.63 pixels mm^-1	h = −6→8
phi and ω scans	k = −16→16
11528 measured reflections	l = −24→24
3885 independent reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.119	H-atom parameters constrained
S = 0.99	w = 1/[σ²(F_o²) + (0.0561P)²] where P = (F_o² + 2F_c²)/3
3885 reflections	(Δ/σ)_max = 0.001
218 parameters	Δρ_max = 0.68 e Å⁻³
10 restraints	Δρ_min = −0.34 e Å⁻³

Crystal data top

C₁₆H₁₃Br₂NO₂S₂	V = 1646.81 (13) Å³
M_r = 475.21	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 6.9200 (3) Å	µ = 5.18 mm⁻¹
b = 12.6556 (6) Å	T = 298 K
c = 18.8743 (8) Å	0.20 × 0.10 × 0.10 mm
β = 94.939 (2)°

Data collection top

Bruker SMART CCD area-detector diffractometer	2405 reflections with I > 2σ(I)
11528 measured reflections	R_int = 0.046
3885 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.047	10 restraints
wR(F²) = 0.119	H-atom parameters constrained
S = 0.99	Δρ_max = 0.68 e Å⁻³
3885 reflections	Δρ_min = −0.34 e Å⁻³
218 parameters

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
Br1	0.13008 (8)	0.55071 (3)	0.35467 (3)	0.05578 (18)
Br2	0.15356 (8)	0.04434 (3)	0.41644 (3)	0.06213 (19)
S1	0.44323 (16)	0.30062 (8)	0.21060 (5)	0.0411 (3)
S2	0.34926 (19)	0.28334 (11)	0.59074 (6)	0.0500 (3)	0.91
S2'	0.3416 (13)	0.1428 (9)	0.5658 (8)	0.070 (4)	0.09
O1	0.6200 (6)	0.0274 (3)	0.3297 (2)	0.0847 (12)
O2	0.7893 (5)	0.1268 (3)	0.26556 (17)	0.0686 (10)
N1	0.6927 (6)	0.1124 (3)	0.3165 (2)	0.0526 (10)
C1	0.1908 (6)	0.2278 (3)	0.3351 (2)	0.0373 (10)
H1	0.2078	0.1787	0.2996	0.045*
C2	0.1618 (5)	0.1933 (3)	0.4029 (2)	0.0359 (9)
C3	0.1406 (6)	0.2625 (3)	0.4590 (2)	0.0383 (10)
C4	0.1303 (6)	0.3690 (3)	0.4410 (2)	0.0382 (10)
H4	0.1068	0.4182	0.4758	0.046*
C5	0.1538 (5)	0.4037 (3)	0.3736 (2)	0.0329 (9)
C6	0.1946 (6)	0.3345 (3)	0.3197 (2)	0.0351 (9)
C7	0.2498 (6)	0.3724 (3)	0.2476 (2)	0.0461 (11)
H7A	0.2874	0.4461	0.2519	0.055*
H7B	0.1355	0.3687	0.2141	0.055*
C8	0.6582 (6)	0.3413 (4)	0.2651 (2)	0.0490 (11)
H8A	0.7714	0.3131	0.2447	0.059*
H8B	0.6671	0.4178	0.2640	0.059*
C9	0.6617 (6)	0.3057 (3)	0.3415 (2)	0.0388 (10)
C10	0.6674 (6)	0.2011 (3)	0.3653 (2)	0.0399 (10)
C11	0.6354 (6)	0.1726 (3)	0.4341 (2)	0.0414 (10)
H11	0.6364	0.1017	0.4470	0.050*
C12	0.6017 (5)	0.2495 (4)	0.4840 (2)	0.0405 (10)
C13	0.6116 (6)	0.3537 (3)	0.4629 (2)	0.0414 (10)
H13	0.5988	0.4067	0.4963	0.050*
C14	0.6398 (5)	0.3814 (3)	0.3939 (2)	0.0406 (10)
H14	0.6443	0.4527	0.3820	0.049*
C15	0.5534 (6)	0.2184 (4)	0.5567 (2)	0.0565 (13)
H15A	0.6666	0.2314	0.5895	0.068*	0.93
H15B	0.5293	0.1429	0.5567	0.068*	0.93
H15C	0.5438	0.2820	0.5849	0.068*	0.07
H15D	0.6630	0.1785	0.5782	0.068*	0.07
C16	0.1441 (6)	0.2292 (4)	0.5353 (2)	0.0507 (12)
H16A	0.1491	0.1527	0.5378	0.061*	0.93
H16B	0.0247	0.2518	0.5541	0.061*	0.93
H16C	0.0229	0.1934	0.5417	0.061*	0.07
H16D	0.1498	0.2914	0.5655	0.061*	0.07

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0760 (4)	0.0390 (2)	0.0522 (3)	0.0092 (2)	0.0046 (3)	−0.0008 (2)
Br2	0.0733 (4)	0.0420 (3)	0.0746 (4)	0.0017 (2)	0.0269 (3)	0.0120 (2)
S1	0.0484 (7)	0.0486 (6)	0.0270 (6)	0.0011 (5)	0.0074 (5)	−0.0040 (5)
S2	0.0590 (9)	0.0652 (8)	0.0267 (6)	0.0065 (6)	0.0086 (6)	−0.0006 (6)
S2'	0.084 (8)	0.076 (7)	0.052 (7)	0.002 (7)	0.014 (6)	0.020 (6)
O1	0.103 (3)	0.061 (2)	0.095 (3)	−0.026 (2)	0.033 (2)	−0.029 (2)
O2	0.071 (3)	0.082 (3)	0.056 (2)	0.0060 (19)	0.0234 (19)	−0.0144 (18)
N1	0.048 (3)	0.060 (3)	0.051 (3)	−0.001 (2)	0.006 (2)	−0.013 (2)
C1	0.036 (2)	0.040 (2)	0.036 (2)	0.0027 (18)	0.0072 (18)	−0.0042 (18)
C2	0.031 (2)	0.039 (2)	0.040 (2)	0.0043 (17)	0.0125 (18)	0.0083 (19)
C3	0.028 (2)	0.054 (2)	0.034 (2)	0.0013 (19)	0.0103 (18)	0.0036 (19)
C4	0.035 (2)	0.048 (2)	0.032 (2)	0.0038 (19)	0.0054 (18)	−0.0049 (19)
C5	0.028 (2)	0.037 (2)	0.035 (2)	0.0006 (17)	0.0042 (17)	0.0004 (17)
C6	0.030 (2)	0.043 (2)	0.032 (2)	0.0032 (17)	0.0005 (17)	−0.0022 (17)
C7	0.054 (3)	0.051 (3)	0.034 (2)	0.009 (2)	0.007 (2)	0.007 (2)
C8	0.047 (3)	0.057 (3)	0.045 (3)	−0.015 (2)	0.012 (2)	0.000 (2)
C9	0.023 (2)	0.060 (3)	0.033 (2)	−0.0078 (19)	0.0046 (17)	−0.001 (2)
C10	0.031 (2)	0.047 (2)	0.041 (3)	0.0025 (19)	−0.0004 (19)	−0.004 (2)
C11	0.029 (2)	0.052 (3)	0.043 (3)	0.0052 (19)	0.0017 (19)	0.007 (2)
C12	0.020 (2)	0.061 (3)	0.039 (2)	0.0014 (19)	−0.0037 (18)	0.002 (2)
C13	0.033 (3)	0.055 (2)	0.036 (2)	0.004 (2)	0.0006 (19)	−0.010 (2)
C14	0.029 (2)	0.048 (2)	0.044 (3)	−0.0035 (19)	−0.0013 (19)	−0.001 (2)
C15	0.054 (3)	0.082 (3)	0.032 (2)	0.008 (3)	−0.004 (2)	0.011 (2)
C16	0.040 (3)	0.070 (3)	0.044 (3)	0.000 (2)	0.011 (2)	0.013 (2)

Geometric parameters (Å, º) top

Br1—C5	1.899 (4)	C7—H7A	0.9700
Br2—C2	1.904 (4)	C7—H7B	0.9700
S1—C7	1.807 (4)	C8—C9	1.509 (5)
S1—C8	1.809 (4)	C8—H8A	0.9700
S2—C15	1.800 (4)	C8—H8B	0.9700
S2—C16	1.823 (4)	C9—C14	1.396 (6)
S2—H15C	1.3601	C9—C10	1.398 (5)
S2—H16D	1.4245	C10—C11	1.384 (6)
S2'—C15	1.771 (9)	C11—C12	1.386 (6)
S2'—C16	1.806 (9)	C11—H11	0.9300
O1—N1	1.222 (5)	C12—C13	1.381 (6)
O2—N1	1.231 (5)	C12—C15	1.493 (6)
N1—C10	1.472 (5)	C13—C14	1.378 (5)
C1—C6	1.382 (5)	C13—H13	0.9300
C1—C2	1.383 (5)	C14—H14	0.9300
C1—H1	0.9300	C15—H15A	0.9700
C2—C3	1.392 (5)	C15—H15B	0.9700
C3—C4	1.390 (6)	C15—H15C	0.9700
C3—C16	1.499 (5)	C15—H15D	0.9700
C4—C5	1.369 (5)	C16—H16A	0.9700
C4—H4	0.9300	C16—H16B	0.9700
C5—C6	1.389 (5)	C16—H16C	0.9700
C6—C7	1.523 (6)	C16—H16D	0.9700

C7—S1—C8	103.8 (2)	C13—C12—C15	122.5 (4)
C15—S2—C16	102.7 (2)	C11—C12—C15	120.2 (4)
C16—S2—H15C	132.5	C14—C13—C12	122.0 (4)
C15—S2—H16D	132.9	C14—C13—H13	119.0
H15C—S2—H16D	155.6	C12—C13—H13	119.0
C15—S2'—C16	104.6 (5)	C13—C14—C9	121.8 (4)
O1—N1—O2	123.4 (4)	C13—C14—H14	119.1
O1—N1—C10	118.0 (4)	C9—C14—H14	119.1
O2—N1—C10	118.6 (4)	C12—C15—S2'	119.0 (6)
C6—C1—C2	120.7 (4)	C12—C15—S2	116.9 (3)
C6—C1—H1	119.6	S2'—C15—S2	62.0 (5)
C2—C1—H1	119.6	C12—C15—H15A	108.1
C1—C2—C3	122.5 (4)	S2'—C15—H15A	131.2
C1—C2—Br2	116.4 (3)	S2—C15—H15A	108.1
C3—C2—Br2	121.0 (3)	C12—C15—H15B	108.1
C4—C3—C2	115.5 (4)	S2'—C15—H15B	47.5
C4—C3—C16	120.3 (4)	S2—C15—H15B	108.1
C2—C3—C16	124.0 (4)	H15A—C15—H15B	107.3
C5—C4—C3	122.1 (4)	C12—C15—H15C	108.5
C5—C4—H4	119.0	S2'—C15—H15C	107.4
C3—C4—H4	119.0	S2—C15—H15C	48.1
C4—C5—C6	121.7 (4)	H15A—C15—H15C	66.4
C4—C5—Br1	118.3 (3)	H15B—C15—H15C	143.0
C6—C5—Br1	120.0 (3)	C12—C15—H15D	107.0
C1—C6—C5	116.9 (4)	S2'—C15—H15D	107.6
C1—C6—C7	120.5 (4)	S2—C15—H15D	134.3
C5—C6—C7	122.6 (4)	H15B—C15—H15D	67.4
C6—C7—S1	116.0 (3)	H15C—C15—H15D	107.0
C6—C7—H7A	108.3	C3—C16—S2'	115.2 (6)
S1—C7—H7A	108.3	C3—C16—S2	113.1 (3)
C6—C7—H7B	108.3	S2'—C16—S2	60.9 (4)
S1—C7—H7B	108.3	C3—C16—H16A	109.0
H7A—C7—H7B	107.4	S2'—C16—H16A	50.0
C9—C8—S1	113.8 (3)	S2—C16—H16A	109.0
C9—C8—H8A	108.8	C3—C16—H16B	109.0
S1—C8—H8A	108.8	S2'—C16—H16B	135.0
C9—C8—H8B	108.8	S2—C16—H16B	109.0
S1—C8—H8B	108.8	H16A—C16—H16B	107.8
H8A—C8—H8B	107.7	C3—C16—H16C	108.0
C14—C9—C10	115.1 (4)	S2'—C16—H16C	108.4
C14—C9—C8	118.6 (4)	S2—C16—H16C	138.0
C10—C9—C8	126.0 (4)	H16A—C16—H16C	63.6
C11—C10—C9	123.1 (4)	H16B—C16—H16C	47.1
C11—C10—N1	115.3 (4)	C3—C16—H16D	109.4
C9—C10—N1	121.5 (4)	S2'—C16—H16D	108.2
C10—C11—C12	120.3 (4)	S2—C16—H16D	50.8
C10—C11—H11	119.9	H16A—C16—H16D	141.5
C12—C11—H11	119.9	H16B—C16—H16D	62.6
C13—C12—C11	117.3 (4)	H16C—C16—H16D	107.4

C6—C1—C2—C3	−1.8 (6)	O1—N1—C10—C9	−150.2 (4)
C6—C1—C2—Br2	178.6 (3)	O2—N1—C10—C9	31.4 (6)
C1—C2—C3—C4	6.4 (6)	C9—C10—C11—C12	−2.1 (6)
Br2—C2—C3—C4	−174.0 (3)	N1—C10—C11—C12	−177.4 (3)
C1—C2—C3—C16	−168.8 (4)	C10—C11—C12—C13	−3.2 (6)
Br2—C2—C3—C16	10.8 (6)	C10—C11—C12—C15	175.7 (4)
C2—C3—C4—C5	−4.6 (6)	C11—C12—C13—C14	4.5 (6)
C16—C3—C4—C5	170.8 (4)	C15—C12—C13—C14	−174.3 (4)
C3—C4—C5—C6	−1.8 (6)	C12—C13—C14—C9	−0.6 (6)
C3—C4—C5—Br1	178.4 (3)	C10—C9—C14—C13	−4.5 (6)
C2—C1—C6—C5	−4.7 (6)	C8—C9—C14—C13	169.8 (4)
C2—C1—C6—C7	172.8 (4)	C13—C12—C15—S2'	117.9 (6)
C4—C5—C6—C1	6.5 (6)	C11—C12—C15—S2'	−60.9 (6)
Br1—C5—C6—C1	−173.7 (3)	C13—C12—C15—S2	46.7 (5)
C4—C5—C6—C7	−171.0 (4)	C11—C12—C15—S2	−132.2 (4)
Br1—C5—C6—C7	8.8 (5)	C16—S2'—C15—C12	−65.4 (9)
C1—C6—C7—S1	−38.9 (5)	C16—S2'—C15—S2	41.5 (5)
C5—C6—C7—S1	138.6 (3)	C16—S2—C15—C12	69.6 (4)
C8—S1—C7—C6	−72.3 (4)	C16—S2—C15—S2'	−40.6 (5)
C7—S1—C8—C9	65.9 (4)	C4—C3—C16—S2'	−127.1 (6)
S1—C8—C9—C14	−109.7 (4)	C2—C3—C16—S2'	47.9 (7)
S1—C8—C9—C10	64.0 (5)	C4—C3—C16—S2	−59.7 (5)
C14—C9—C10—C11	5.9 (6)	C2—C3—C16—S2	115.3 (4)
C8—C9—C10—C11	−168.0 (4)	C15—S2'—C16—C3	62.2 (9)
C14—C9—C10—N1	−179.1 (4)	C15—S2'—C16—S2	−41.3 (5)
C8—C9—C10—N1	7.0 (6)	C15—S2—C16—C3	−66.9 (4)
O1—N1—C10—C11	25.2 (6)	C15—S2—C16—S2'	40.2 (5)
O2—N1—C10—C11	−153.2 (4)

Experimental details

Crystal data
Chemical formula	C₁₆H₁₃Br₂NO₂S₂
M_r	475.21
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	298
a, b, c (Å)	6.9200 (3), 12.6556 (6), 18.8743 (8)
β (°)	94.939 (2)
V (Å³)	1646.81 (13)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	5.18
Crystal size (mm)	0.20 × 0.10 × 0.10

Data collection
Diffractometer	Bruker SMART CCD area-detector
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	11528, 3885, 2405
R_int	0.046
(sin θ/λ)_max (Å⁻¹)	0.667

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.047, 0.119, 0.99
No. of reflections	3885
No. of parameters	218
No. of restraints	10
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.68, −0.34

Computer programs: SMART (Bruker, 2001), SAINT-Plus (Bruker, 2001), SHELXS97 (Sheldrick, 2008), PLATON (Spek, 2009).

Acknowledgements

The authors are grateful to Professor Sheng-Hua Liu for technical assistance with the structure analysis and Dr Xiang-Gao Meng for the data collection.

References

Bruker (2001). SAINT-Plus and SMART. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
Wang, W., Xu, J., Zhang, X. & Lai, Y. H. (2006). Macromol. Chem. 39, 7277–7285. CAS Google Scholar
Xu, J. W., Wang, W. L., Lin, T. T., Sun, Z. & Lai, Y. H. (2008). Supramol. Chem. 20, 723–730. Web of Science CSD CrossRef CAS Google Scholar