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

Zhang, H.; Liu, W.

doi:10.1107/S1600536811048458

organic compounds

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ISSN: 2056-9890

Volume 67| Part 12| December 2011| Page o3413

https://doi.org/10.1107/S1600536811048458

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

Hua Zhang ^a ^* and Wenju Liu ^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: zhhua2011@126.com

(Received 12 October 2011; accepted 15 November 2011; online 23 November 2011)

In the title compound [systematic name: 13,15-dibromo-3,10-dithiatricyclo[10.2.2.2^5,8]octadeca-1(14),5,7,12,15,17-hexaene-6-carbonitrile], C₁₇H₁₃Br₂NS₂, the mean planes of the benzene rings are almost parallel, making a dihedral angle of 1.1 (2)°, and the distance between the ring centroids is 3.294 (3) Å, which is shorter than the normal packing distance of aromatic rings (about 3.4 Å), indicating a strong π–π interaction. The S atom of one bridging chain is disorderd over two positions with site occupancies of 0.605 (4) and 0.395 (4) for the major and minor components, respectively.

Related literature

For the preparation of the title compound, see: Wang et al. (2006 ). For related structures, see: Clément et al. (2009 ); Jin & Lu (2010 ).

Experimental

Crystal data

C₁₇H₁₃Br₂NS₂
M_r = 455.22
Triclinic, $[P \overline 1]$
a = 6.9433 (11) Å
b = 9.0591 (14) Å
c = 13.888 (2) Å
α = 79.825 (2)°
β = 85.047 (3)°
γ = 76.275 (2)°
V = 834.4 (2) Å³
Z = 2
Mo Kα radiation
μ = 5.10 mm⁻¹
T = 298 K
0.2 × 0.2 × 0.2 mm

Data collection

Bruker SMART CCD area-detector diffractometer
5570 measured reflections
3395 independent reflections
2589 reflections with I > 2σ(I)
R_int = 0.098

Refinement

R[F² > 2σ(F²)] = 0.059
wR(F²) = 0.152
S = 0.99
3395 reflections
209 parameters
H-atom parameters constrained
Δρ_max = 1.39 e Å⁻³
Δρ_min = −0.79 e Å⁻³

Data collection: SMART (Bruker, 1999 ); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536811048458/zq2128sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811048458/zq2128Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536811048458/zq2128Isup3.cml

checkCIF report

Comment top

The benzene dimer of [2,2]paracyclophane is know to play a significant role in chiral catalysis, molecular electronics, and organic solar cells. However, the [3,3]paracyclophane building blocks, which are synthetically more accessible, have received less attention (Clément et al., 2009; Jin & Lu, 2010). Here we report the crystal structure of the title compound, a novel dithia[3,3]paracyclophane bearing cyano and bromido groups.

In the structure of the title compound, C₁₇H₁₃Br₂N₁S₂, the mean planes of the benzene rings are almost parallel with a dihedral angle of 1.1 (2)° and the distance between the centroids of the rings is 3.294 (3) Å, values obtained by the program PLATON (Spek, 2009), which is shorter than the normal packing distance of aromatic rings (about 3.4 Å), indicates a strong π-π interaction. The S atom of one bridging chain is disorderd over two positions with site occupancies of 0.605 (4) and 0.395 (4) for the major and minor components, respectively.

Related literature top

For the preparation of the title compound, see: Wang et al. (2006). For related structures, see: Clément et al. (2009); Jin & Lu (2010).

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-cyanobenzene (2.89, 10 mmol) in degassed THF (500 mL) was added dropwise under N₂ over 12 hours to a refluxing solution of potassium carbonate (6.9 g, 50 mmol) in EtOH (1.5L). After additional 2 hours at the reflux temperature (473 K), the mixture was cooled down and the solvent was removed. The resulting residue was treated with CH₂Cl₂(500 mL) and water (500 mL). The organic phase was separated, and the aqueous phase extracted with CH₂Cl₂ (three times). The combined organic layers were dried over Na₂SO₄, then the solvent was removed, and the resulting solid was chromatographed on silica gel using CH₂Cl₂/petroleum ether (1:1, v/v) as eluent. The product was further purified by recrystallization from toluene (Wang et al., 2006).

Structure description top

For the preparation of the title compound, see: Wang et al. (2006). For related structures, see: Clément et al. (2009); Jin & Lu (2010).

Computing details top

Data collection: SMART (Bruker, 1999); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

Fig. 1. Molecular structure of the title compound showing the atom labeling scheme. Displacement ellipsoids are drawn at the 50% probability level.

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

Crystal data top

C₁₇H₁₃Br₂NS₂	Z = 2
M_r = 455.22	F(000) = 448
Triclinic, P1	D_x = 1.812 Mg m⁻³ D_m = 1.812 Mg m⁻³ D_m measured by not measured
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.9433 (11) Å	Cell parameters from 2268 reflections
b = 9.0591 (14) Å	θ = 2.6–26.9°
c = 13.888 (2) Å	µ = 5.10 mm⁻¹
α = 79.825 (2)°	T = 298 K
β = 85.047 (3)°	Block, colourless
γ = 76.275 (2)°	0.2 × 0.2 × 0.2 mm
V = 834.4 (2) Å³

Data collection top

Bruker SMART CCD area-detector diffractometer	2589 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.098
Graphite monochromator	θ_max = 26.5°, θ_min = 2.6°
phi and ω scans	h = −8→8
5570 measured reflections	k = −8→11
3395 independent reflections	l = −17→17

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)] = 0.059	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.152	H-atom parameters constrained
S = 0.99	w = 1/[σ²(F_o²) + (0.0859P)²] where P = (F_o² + 2F_c²)/3
3395 reflections	(Δ/σ)_max < 0.001
209 parameters	Δρ_max = 1.39 e Å⁻³
0 restraints	Δρ_min = −0.79 e Å⁻³

Crystal data top

C₁₇H₁₃Br₂NS₂	γ = 76.275 (2)°
M_r = 455.22	V = 834.4 (2) Å³
Triclinic, P1	Z = 2
a = 6.9433 (11) Å	Mo Kα radiation
b = 9.0591 (14) Å	µ = 5.10 mm⁻¹
c = 13.888 (2) Å	T = 298 K
α = 79.825 (2)°	0.2 × 0.2 × 0.2 mm
β = 85.047 (3)°

Data collection top

Bruker SMART CCD area-detector diffractometer	2589 reflections with I > 2σ(I)
5570 measured reflections	R_int = 0.098
3395 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.059	0 restraints
wR(F²) = 0.152	H-atom parameters constrained
S = 0.99	Δρ_max = 1.39 e Å⁻³
3395 reflections	Δρ_min = −0.79 e Å⁻³
209 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	0.19006 (10)	0.46219 (7)	0.63111 (4)	0.0629 (2)
Br2	0.19842 (8)	−0.21517 (6)	0.88825 (4)	0.0464 (2)
C1	0.1424 (6)	0.2546 (5)	0.8092 (3)	0.0361 (10)
C2	0.1398 (7)	0.1089 (6)	0.8587 (3)	0.0356 (10)
H2	0.0889	0.0972	0.9230	0.043*
C3	0.2114 (7)	−0.0199 (5)	0.8146 (3)	0.0339 (10)
C4	0.2923 (7)	−0.0096 (6)	0.7187 (3)	0.0369 (11)
C5	0.2780 (7)	0.1387 (6)	0.6673 (4)	0.0415 (11)
H5	0.3207	0.1511	0.6016	0.050*
C6	0.2027 (7)	0.2682 (6)	0.7104 (3)	0.0368 (10)
C7	0.0888 (8)	0.3899 (6)	0.8638 (4)	0.0453 (12)
H7A	−0.0409	0.3925	0.8965	0.054*
H7B	0.0795	0.4841	0.8170	0.054*
C8	0.4903 (8)	0.4041 (6)	0.8808 (4)	0.0415 (11)
H8A	0.4578	0.4927	0.8296	0.050*
H8B	0.5828	0.4251	0.9223	0.050*
C9	0.5938 (6)	0.2654 (5)	0.8335 (3)	0.0348 (10)
C10	0.6660 (7)	0.2871 (6)	0.7371 (3)	0.0379 (11)
H10	0.6646	0.3858	0.7037	0.045*
C11	0.7408 (7)	0.1592 (6)	0.6908 (3)	0.0356 (10)
C12	0.7430 (7)	0.0109 (6)	0.7372 (3)	0.0364 (10)
C13	0.6858 (7)	−0.0087 (6)	0.8371 (3)	0.0373 (10)
H13	0.6966	−0.1074	0.8724	0.045*
C14	0.6140 (7)	0.1168 (6)	0.8829 (3)	0.0364 (10)
H14	0.5777	0.1013	0.9493	0.044*
C15	0.8063 (8)	0.1878 (7)	0.5885 (4)	0.0468 (12)
C16	0.7960 (8)	−0.1264 (6)	0.6838 (4)	0.0482 (13)
H16A	0.9294	−0.1836	0.6994	0.058*	0.395 (4)
H16B	0.7961	−0.0895	0.6138	0.058*	0.395 (4)
H16C	0.8168	−0.2192	0.7323	0.058*	0.605 (4)
H16D	0.9207	−0.1252	0.6467	0.058*	0.605 (4)
C17	0.3949 (8)	−0.1478 (7)	0.6717 (4)	0.0516 (14)
H17A	0.4111	−0.1128	0.6019	0.062*	0.395 (4)
H17B	0.3062	−0.2178	0.6798	0.062*	0.395 (4)
H17C	0.3017	−0.1686	0.6305	0.062*	0.605 (4)
H17D	0.4250	−0.2359	0.7234	0.062*	0.605 (4)
N1	0.8583 (9)	0.2087 (7)	0.5092 (4)	0.0690 (15)
S1	0.26512 (19)	0.38462 (15)	0.95384 (9)	0.0416 (3)
S2	0.6293 (3)	−0.2551 (2)	0.71362 (17)	0.0475 (7)	0.605 (4)
S2'	0.6129 (6)	−0.1365 (5)	0.6023 (2)	0.0512 (11)	0.395 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0747 (5)	0.0392 (4)	0.0662 (4)	−0.0073 (3)	−0.0055 (3)	0.0078 (3)
Br2	0.0501 (3)	0.0295 (3)	0.0566 (3)	−0.0066 (2)	0.0044 (2)	−0.0060 (2)
C1	0.025 (2)	0.026 (2)	0.056 (3)	0.0008 (18)	−0.0029 (19)	−0.012 (2)
C2	0.030 (2)	0.035 (3)	0.043 (2)	−0.006 (2)	0.0038 (18)	−0.012 (2)
C3	0.030 (2)	0.026 (2)	0.044 (2)	−0.0042 (19)	0.0019 (18)	−0.007 (2)
C4	0.028 (2)	0.039 (3)	0.046 (3)	−0.007 (2)	0.0014 (19)	−0.016 (2)
C5	0.035 (3)	0.048 (3)	0.041 (3)	−0.007 (2)	−0.002 (2)	−0.006 (2)
C6	0.031 (2)	0.030 (2)	0.048 (3)	−0.0033 (19)	−0.0022 (19)	−0.006 (2)
C7	0.040 (3)	0.033 (3)	0.060 (3)	0.001 (2)	0.002 (2)	−0.016 (2)
C8	0.039 (3)	0.029 (3)	0.056 (3)	−0.005 (2)	0.008 (2)	−0.016 (2)
C9	0.027 (2)	0.031 (3)	0.046 (3)	−0.0044 (19)	0.0043 (18)	−0.012 (2)
C10	0.035 (2)	0.031 (3)	0.048 (3)	−0.008 (2)	0.001 (2)	−0.007 (2)
C11	0.027 (2)	0.039 (3)	0.039 (2)	−0.006 (2)	0.0017 (18)	−0.008 (2)
C12	0.026 (2)	0.038 (3)	0.044 (3)	−0.002 (2)	0.0026 (18)	−0.012 (2)
C13	0.032 (2)	0.031 (3)	0.044 (3)	0.000 (2)	0.0033 (19)	−0.005 (2)
C14	0.032 (2)	0.037 (3)	0.038 (2)	−0.006 (2)	0.0046 (18)	−0.006 (2)
C15	0.047 (3)	0.047 (3)	0.044 (3)	−0.005 (3)	0.005 (2)	−0.012 (2)
C16	0.039 (3)	0.040 (3)	0.066 (3)	−0.005 (2)	0.016 (2)	−0.023 (3)
C17	0.050 (3)	0.043 (3)	0.066 (3)	−0.009 (3)	0.007 (3)	−0.027 (3)
N1	0.088 (4)	0.063 (4)	0.055 (3)	−0.021 (3)	0.014 (3)	−0.009 (3)
S1	0.0478 (7)	0.0338 (7)	0.0433 (7)	−0.0065 (6)	0.0111 (5)	−0.0165 (5)
S2	0.0434 (12)	0.0253 (11)	0.0718 (15)	−0.0028 (9)	0.0121 (10)	−0.0163 (10)
S2'	0.056 (2)	0.058 (2)	0.0412 (18)	−0.0094 (18)	0.0122 (15)	−0.0259 (16)

Geometric parameters (Å, º) top

Br1—C6	1.889 (5)	C11—C12	1.381 (7)
Br2—C3	1.899 (5)	C11—C15	1.451 (7)
C1—C2	1.379 (6)	C12—C13	1.401 (7)
C1—C6	1.393 (7)	C12—C16	1.515 (7)
C1—C7	1.510 (7)	C13—C14	1.370 (7)
C2—C3	1.381 (7)	C13—H13	0.9300
C2—H2	0.9300	C14—H14	0.9300
C3—C4	1.397 (6)	C15—N1	1.126 (7)
C4—C5	1.391 (7)	C16—S2'	1.802 (7)
C4—C17	1.512 (7)	C16—S2	1.805 (5)
C5—C6	1.383 (7)	C16—H16A	0.9700
C5—H5	0.9300	C16—H16B	0.9700
C7—S1	1.811 (5)	C16—H16C	0.9700
C7—H7A	0.9700	C16—H16D	0.9700
C7—H7B	0.9700	C17—S2'	1.737 (6)
C8—C9	1.519 (7)	C17—S2	1.774 (6)
C8—S1	1.816 (5)	C17—H17A	0.9700
C8—H8A	0.9700	C17—H17B	0.9700
C8—H8B	0.9700	C17—H17C	0.9700
C9—C14	1.380 (7)	C17—H17D	0.9700
C9—C10	1.385 (6)	S2—H16C	1.4691
C10—C11	1.396 (7)	S2—H17D	1.3851
C10—H10	0.9300

C2—C1—C6	117.4 (4)	C12—C16—S2'	115.1 (4)
C2—C1—C7	119.6 (4)	C12—C16—S2	113.9 (4)
C6—C1—C7	123.0 (4)	S2'—C16—S2	56.8 (2)
C1—C2—C3	121.3 (4)	C12—C16—H16A	108.8
C1—C2—H2	119.3	S2'—C16—H16A	135.9
C3—C2—H2	119.3	S2—C16—H16A	108.8
C2—C3—C4	121.9 (4)	C12—C16—H16B	108.8
C2—C3—Br2	118.2 (3)	S2'—C16—H16B	54.2
C4—C3—Br2	119.9 (4)	S2—C16—H16B	108.8
C5—C4—C3	115.8 (4)	H16A—C16—H16B	107.7
C5—C4—C17	120.5 (4)	C12—C16—H16C	108.1
C3—C4—C17	123.7 (5)	S2'—C16—H16C	108.4
C6—C5—C4	122.3 (4)	S2—C16—H16C	54.4
C6—C5—H5	118.8	H16A—C16—H16C	59.6
C4—C5—H5	118.8	H16B—C16—H16C	143.1
C5—C6—C1	120.6 (4)	C12—C16—H16D	108.8
C5—C6—Br1	117.6 (4)	S2'—C16—H16D	108.7
C1—C6—Br1	121.7 (4)	S2—C16—H16D	137.0
C1—C7—S1	113.7 (4)	H16A—C16—H16D	50.1
C1—C7—H7A	108.8	H16B—C16—H16D	60.1
S1—C7—H7A	108.8	H16C—C16—H16D	107.4
C1—C7—H7B	108.8	C4—C17—S2'	117.2 (4)
S1—C7—H7B	108.8	C4—C17—S2	118.4 (4)
H7A—C7—H7B	107.7	S2'—C17—S2	58.5 (2)
C9—C8—S1	115.4 (3)	C4—C17—H17A	107.7
C9—C8—H8A	108.4	S2'—C17—H17A	51.6
S1—C8—H8A	108.4	S2—C17—H17A	107.7
C9—C8—H8B	108.4	C4—C17—H17B	107.7
S1—C8—H8B	108.4	S2'—C17—H17B	134.1
H8A—C8—H8B	107.5	S2—C17—H17B	107.7
C14—C9—C10	118.5 (4)	H17A—C17—H17B	107.1
C14—C9—C8	121.9 (4)	C4—C17—H17C	108.2
C10—C9—C8	119.6 (4)	S2'—C17—H17C	108.3
C9—C10—C11	119.2 (4)	S2—C17—H17C	132.5
C9—C10—H10	120.4	H17A—C17—H17C	63.7
C11—C10—H10	120.4	H17B—C17—H17C	45.3
C12—C11—C10	122.2 (4)	C4—C17—H17D	107.8
C12—C11—C15	120.3 (5)	S2'—C17—H17D	107.7
C10—C11—C15	117.3 (4)	S2—C17—H17D	50.9
C11—C12—C13	117.2 (4)	H17A—C17—H17D	144.4
C11—C12—C16	122.7 (4)	H17B—C17—H17D	64.1
C13—C12—C16	120.1 (4)	H17C—C17—H17D	107.1
C14—C13—C12	120.3 (4)	C7—S1—C8	103.7 (2)
C14—C13—H13	119.8	C17—S2—C16	106.1 (3)
C12—C13—H13	119.8	C17—S2—H16C	135.9
C13—C14—C9	122.0 (4)	C16—S2—H17D	134.8
C13—C14—H14	119.0	H16C—S2—H17D	152.9
C9—C14—H14	119.0	C17—S2'—C16	107.8 (3)
N1—C15—C11	179.4 (7)

C6—C1—C2—C3	5.8 (7)	C10—C11—C12—C16	171.0 (5)
C7—C1—C2—C3	−171.8 (4)	C15—C11—C12—C16	−5.2 (7)
C1—C2—C3—C4	0.9 (7)	C11—C12—C13—C14	5.8 (7)
C1—C2—C3—Br2	−179.2 (3)	C16—C12—C13—C14	−171.8 (5)
C2—C3—C4—C5	−6.2 (7)	C12—C13—C14—C9	0.5 (7)
Br2—C3—C4—C5	174.0 (3)	C10—C9—C14—C13	−6.2 (7)
C2—C3—C4—C17	172.2 (5)	C8—C9—C14—C13	172.1 (5)
Br2—C3—C4—C17	−7.6 (6)	C11—C12—C16—S2'	−71.3 (6)
C3—C4—C5—C6	4.9 (7)	C13—C12—C16—S2'	106.1 (5)
C17—C4—C5—C6	−173.7 (5)	C11—C12—C16—S2	−134.3 (4)
C4—C5—C6—C1	1.8 (7)	C13—C12—C16—S2	43.1 (6)
C4—C5—C6—Br1	−179.4 (3)	C5—C4—C17—S2'	41.4 (7)
C2—C1—C6—C5	−7.2 (7)	C3—C4—C17—S2'	−137.1 (5)
C7—C1—C6—C5	170.4 (5)	C5—C4—C17—S2	108.4 (5)
C2—C1—C6—Br1	174.1 (3)	C3—C4—C17—S2	−70.0 (6)
C7—C1—C6—Br1	−8.4 (6)	C1—C7—S1—C8	65.3 (4)
C2—C1—C7—S1	66.7 (5)	C9—C8—S1—C7	−70.7 (4)
C6—C1—C7—S1	−110.8 (5)	C4—C17—S2—C16	−64.2 (5)
S1—C8—C9—C14	−41.7 (6)	S2'—C17—S2—C16	42.0 (3)
S1—C8—C9—C10	136.6 (4)	C12—C16—S2—C17	64.3 (5)
C14—C9—C10—C11	5.4 (7)	S2'—C16—S2—C17	−41.1 (3)
C8—C9—C10—C11	−172.9 (4)	C4—C17—S2'—C16	65.6 (5)
C9—C10—C11—C12	0.9 (7)	S2—C17—S2'—C16	−42.6 (3)
C9—C10—C11—C15	177.2 (4)	C12—C16—S2'—C17	−60.5 (5)
C10—C11—C12—C13	−6.5 (7)	S2—C16—S2'—C17	42.6 (3)
C15—C11—C12—C13	177.3 (4)

Experimental details

Crystal data
Chemical formula	C₁₇H₁₃Br₂NS₂
M_r	455.22
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	6.9433 (11), 9.0591 (14), 13.888 (2)
α, β, γ (°)	79.825 (2), 85.047 (3), 76.275 (2)
V (Å³)	834.4 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	5.10
Crystal size (mm)	0.2 × 0.2 × 0.2

Data collection
Diffractometer	Bruker SMART CCD area-detector
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	5570, 3395, 2589
R_int	0.098
(sin θ/λ)_max (Å⁻¹)	0.628

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.059, 0.152, 0.99
No. of reflections	3395
No. of parameters	209
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.39, −0.79

Computer programs: SMART (Bruker, 1999), SAINT (Bruker, 1999), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Acknowledgements

The authors thank Dr Xiang-Gao Meng for the data collection.

References

Bruker (1999). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Clément, S., Guyard, L., Knorr, M., Däschlein, C. & Strohmann, C. (2009). Acta Cryst. E65, o528. Web of Science CSD CrossRef IUCr Journals Google Scholar
Jin, G. & Lu, Y. (2010). Acta Cryst. E66, o2144. Web of Science CSD CrossRef IUCr Journals Google Scholar
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