trans-1,2-Bis(3,5-dimethoxy­phen­yl)ethene

Ritter, S.; Neudörfl, J.-M.; Velder, J.; Schmalz, H.-G.

doi:10.1107/S160053680903116X

organic compounds

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ISSN: 2056-9890

Volume 65| Part 9| September 2009| Page o2150

doi:10.1107/S160053680903116X

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trans-1,2-Bis(3,5-dimethoxyphenyl)ethene

Stefanie Ritter,^a Jörg-M. Neudörfl,^a Janna Velder ^a and Hans-Günther Schmalz ^a ^*

^aDepartment für Chemie der Universität zu Köln, Greinstrasse 4, 50939 Köln, Germany
^*Correspondence e-mail: schmalz@uni-koeln.de

(Received 3 August 2009; accepted 6 August 2009; online 15 August 2009)

The title compound, C₁₈H₂₀O₄, was prepared in high yield from 3,5-dimethoxystyrene via a Ru-catalysed homo-olefin metathesis. Exclusive formation of the E-configurated isomer was observed. Interestingly, one symmetric unit contains two molecules adopting an s-syn-anti and and an all-s-anti conformation.

Related literature

For the preparation of differently substituted stilbenes using a Ru-catalysed metathesis strategy, see: Velder et al. (2006 ). Alternative methodologies for the synthesis of oxy-functionalized stilbenes using Wittig-type olefinations or Heck couplings have been described by Kim et al. (2002 ), Lion et al. (2005 ), Botella & Nayera (2004 ) and Reetz et al. (1998 ). For the bioactivity of various stilbenes with a focus on their anticancer activity, see: Aggarwal et al. (2004 ); Wolter & Stein (2002 ); Fremont (2000 ); Jang et al. (1997 ); Wieder et al. (2001 ). For related structures and syntheses see: Yin et al. (2002 ); Uda et al. (2002 ).

Experimental

Crystal data

C₁₈H₂₀O₄
M_r = 300.34
Monoclinic, P 2₁ /c
a = 7.1954 (3) Å
b = 9.4203 (4) Å
c = 22.6762 (5) Å
β = 93.783 (2)°
V = 1533.71 (10) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 100 K
0.4 × 0.2 × 0.2 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: none
7687 measured reflections
3320 independent reflections
2142 reflections with I > 2σ(I)
R_int = 0.041

Refinement

R[F² > 2σ(F²)] = 0.055
wR(F²) = 0.150
S = 1.03
3320 reflections
207 parameters
H-atom parameters constrained
Δρ_max = 0.24 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Data collection: COLLECT (Hooft, 1998 ); cell refinement: DENZO (Otwinowski & Minor, 1997 ); data reduction: DENZO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SCHAKAL99 (Keller 1999 ); software used to prepare material for publication: PLATON (Spek, 2009 ) and enCIFer (Allen et al., 2004 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053680903116X/hg2547sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053680903116X/hg2547Isup2.hkl

checkCIF report

Comment top

In recent years, polyhydroxylated stilbenes such as resveratrol have gained a tremendous importance especially due to their potential for the prevention and therapy of cancer (Aggarwal et al. (2004), Wolter et al. (2002), Fremont (2000), Jang et al. (1997)). In the course of our own research in the field of bioactive stilbenes (Wieder et al. (2001)) we were able to develop a highly efficient synthetic route towards symmetrically as well as unsymmetrically substituted E-stilbenes applying a Ru-catalyzed metathesis strategy (Velder et al. (2006)). Alternative strategies for the synthesis of stilbenes are based on Wittig-type olefinations or Heck couplings (Kim et al. (2002), Lion et al. (2005), Botella et al. (2004), Reetz et al. (1998). One of the compounds prepared was the title compound trans-1,2-bis-(3,5-dimethoxyphenyl)ethene. The asymmetric unit contains two molecules, A and B, both of which exhibit a center of symmetry (figure 1). The 3,5-dimethoxy groups of molecule B all adopt a s-anti configuration, whereas in molecule A, a s-syn as well as a s-anti conformation is found on both sides. Zhang and co-workers reported the same observation on a related structure (Yin et al., 2002). The torsion angles between the benzene ring planes in molecule A are 0.2 (3)° (C1a—C1—C2—C3), which gives the molecule a planar shape. Molecule B, in contrast, adopts a slightly twisted conformation with a torsion angle of 7.0 (2)° (C10b—C10—C11—C12). The molecules form slightly twisted pseudo-layers which are arranged along the b axis (Fig. 2). In figure 3, two of those pseudo-layers are shown from the top view (with the front layer being displayed in dark and the retral layer in light green).

Related literature top

For the preparation of differently substituted stilbenes using a Ru-catalysed metathesis strategy, see: Velder et al. (2006). Alternative methodologies for the synthesis of oxy-functionalized stilbenes using Wittig-type olefinations or Heck couplings have been described by Kim et al. (2002), Lion et al. (2005), Botella et al. (2004) and Reetz et al. (1998). For the bioactivity of various stilbenes with a focus on their anticancer activity, see: Aggarwal et al. (2004); Wolter et al. (2002); Fremont (2000); Jang et al. (1997); Wieder et al. (2001). For related structures and syntheses see: Yin et al. (2002); Uda et al. (2002).

Experimental top

In a glove-box (Labmaster 130, mBraun), the catalyst (Grubbs-II, 2 mol %) was weighted into a 25 ml Schlenk tube, which was then sealed with a rubber septum. This was then taken out of the box, connected to an Ar-vacuum double manifold and equipped with a reflux condenser under argon. A solution of 3,5-dimethoxy-styrene (1 mmol) in CH₂Cl₂ (10 ml) was then added via syringe and the resulting solution was refluxed for 1.5 h under argon. After allowing the reaction mixture to cool to room temperature, the solvent was evaporated in vacuo and the crude product was purified by flash chromatography (SiO₂, cyclohexane/ ethyl acetate = 10:1) to give 138 mg (0.46 mmol; 92%) of the homo metathesis product (1). mp. 142 °C (Uda et al., 2002: 141–144 °C). 1H NMR (300 MHz, CDCl₃): δ = 3.81 (s, 6H, OCH₃), 6.4 (t, 1H, J = 2.1 Hz,H-4), 6.67 (d, 2H, J = 2.1 Hz, H-2, H-6), 7.00 (s, 1H, H-7); ¹³C NMR (75 MHz, CDCl₃): δ = 55.4 (OCH₃), 100.2 (C-4), 104.7 (C-2, C-6), 129.2 (C-7), 139.2 (C-1), 161.0 (C-3, C-5); HRMS, calcd for C₁₈H₂₀O₄ (M⁺) 300.1361, found 300.136.

Computing details top

Data collection: COLLECT (Hooft, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997); data reduction: DENZO (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SCHAKAL99 (Keller 1999); software used to prepare material for publication: PLATON (Spek, 2009) and enCIFer (Allen et al., 2004).

Figures top

	Fig. 1. A view of (1). Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. View of the unit cell along the b axis.
	Fig. 3. Top view of two pseudo layers.

trans-1,2-Bis(3,5-dimethoxyphenyl)ethene top

Crystal data top

C₁₈H₂₀O₄	F(000) = 640
M_r = 300.34	D_x = 1.301 Mg m⁻³
Monoclinic, P2₁/c	Melting point: 142 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 7.1954 (3) Å	Cell parameters from 7687 reflections
b = 9.4203 (4) Å	θ = 2.3–27.0°
c = 22.6762 (5) Å	µ = 0.09 mm⁻¹
β = 93.783 (2)°	T = 100 K
V = 1533.71 (10) Å³	Needle, colourless
Z = 4	0.4 × 0.2 × 0.2 mm

Data collection top

Nonius KappaCCD diffractometer	2142 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.041
Graphite monochromator	θ_max = 27.0°, θ_min = 2.3°
ϕ and ω scans	h = −6→9
7687 measured reflections	k = −12→10
3320 independent reflections	l = −25→28

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)] = 0.055	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.150	H-atom parameters constrained
S = 1.03	w = 1/[σ²(F_o²) + (0.0722P)² + 0.274P] where P = (F_o² + 2F_c²)/3
3320 reflections	(Δ/σ)_max < 0.001
207 parameters	Δρ_max = 0.24 e Å⁻³
0 restraints	Δρ_min = −0.24 e Å⁻³

Crystal data top

C₁₈H₂₀O₄	V = 1533.71 (10) Å³
M_r = 300.34	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 7.1954 (3) Å	µ = 0.09 mm⁻¹
b = 9.4203 (4) Å	T = 100 K
c = 22.6762 (5) Å	0.4 × 0.2 × 0.2 mm
β = 93.783 (2)°

Data collection top

Nonius KappaCCD diffractometer	2142 reflections with I > 2σ(I)
7687 measured reflections	R_int = 0.041
3320 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.055	0 restraints
wR(F²) = 0.150	H-atom parameters constrained
S = 1.03	Δρ_max = 0.24 e Å⁻³
3320 reflections	Δρ_min = −0.24 e Å⁻³
207 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. The coordinates of the hydrogenatoms are constrained, and the U values of the H atoms are constrained relative to the U_eq of the atom the hydrogen binds to (1.2 for CH and CH₂, 1.5 for CH₃).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.16550 (18)	0.11969 (13)	0.29039 (5)	0.0322 (4)
O2	0.11990 (18)	0.52539 (13)	0.41414 (6)	0.0346 (4)
C1	0.0096 (2)	0.07001 (18)	0.49846 (8)	0.0272 (4)
H1	−0.0099	0.1220	0.5334	0.033*
C2	0.0575 (2)	0.15286 (19)	0.44674 (8)	0.0256 (4)
C3	0.0903 (2)	0.0879 (2)	0.39261 (8)	0.0268 (4)
H3	0.0831	−0.0123	0.3885	0.032*
C4	0.1329 (2)	0.17169 (19)	0.34549 (8)	0.0259 (4)
C5	0.1450 (2)	0.31913 (19)	0.35017 (8)	0.0275 (4)
H5	0.1748	0.3753	0.3173	0.033*
C6	0.1123 (2)	0.38210 (19)	0.40394 (8)	0.0267 (4)
C7	0.0691 (2)	0.2989 (2)	0.45200 (8)	0.0274 (4)
H7	0.0475	0.3428	0.4886	0.033*
C8	0.1666 (3)	−0.03060 (19)	0.28252 (8)	0.0312 (5)
H8A	0.2575	−0.0734	0.3113	0.047*
H8B	0.2006	−0.0530	0.2424	0.047*
H8C	0.0424	−0.0687	0.2884	0.047*
C9	0.1455 (3)	0.6156 (2)	0.36467 (9)	0.0359 (5)
H9A	0.2645	0.5933	0.3482	0.054*
H9B	0.1457	0.7149	0.3775	0.054*
H9C	0.0437	0.6003	0.3344	0.054*
O3	0.31579 (18)	0.49045 (14)	0.21349 (5)	0.0360 (4)
O4	0.33384 (18)	0.03486 (14)	0.13362 (6)	0.0392 (4)
C10	0.4952 (2)	0.43244 (19)	0.00794 (8)	0.0299 (4)
H10	0.5284	0.3637	−0.0202	0.040 (6)*
C11	0.4382 (2)	0.3787 (2)	0.06489 (8)	0.0273 (4)
C12	0.4051 (2)	0.4693 (2)	0.11208 (8)	0.0289 (4)
H12	0.4206	0.5689	0.1083	0.020 (5)*
C13	0.3493 (2)	0.4114 (2)	0.16439 (8)	0.0288 (5)
C14	0.3246 (2)	0.2665 (2)	0.17034 (8)	0.0303 (5)
H14	0.2849	0.2285	0.2062	0.047 (6)*
C15	0.3581 (2)	0.1774 (2)	0.12378 (8)	0.0296 (5)
C16	0.4155 (2)	0.2328 (2)	0.07095 (8)	0.0293 (5)
H16	0.4391	0.1711	0.0392	0.030 (5)*
C17	0.3394 (3)	0.6410 (2)	0.20992 (9)	0.0373 (5)
H17A	0.4679	0.6625	0.2011	0.056*
H17B	0.3128	0.6845	0.2477	0.056*
H17C	0.2536	0.6792	0.1785	0.056*
C18	0.3671 (3)	−0.0593 (2)	0.08589 (9)	0.0386 (5)
H18A	0.2853	−0.0340	0.0512	0.058*
H18B	0.3415	−0.1571	0.0976	0.058*
H18C	0.4974	−0.0514	0.0761	0.058*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0478 (8)	0.0283 (7)	0.0216 (7)	−0.0022 (6)	0.0118 (6)	0.0006 (6)
O2	0.0487 (8)	0.0268 (8)	0.0291 (8)	−0.0033 (6)	0.0080 (6)	0.0032 (6)
C1	0.0288 (9)	0.0332 (10)	0.0200 (9)	0.0004 (8)	0.0046 (7)	−0.0001 (8)
C2	0.0249 (9)	0.0291 (11)	0.0227 (10)	0.0000 (8)	0.0014 (7)	0.0040 (8)
C3	0.0280 (10)	0.0261 (10)	0.0265 (11)	−0.0010 (7)	0.0028 (8)	0.0025 (8)
C4	0.0256 (9)	0.0307 (11)	0.0216 (10)	0.0010 (8)	0.0034 (7)	0.0005 (8)
C5	0.0291 (10)	0.0288 (11)	0.0252 (10)	−0.0006 (8)	0.0053 (8)	0.0073 (8)
C6	0.0269 (10)	0.0249 (10)	0.0281 (11)	−0.0020 (8)	0.0008 (8)	0.0025 (8)
C7	0.0294 (10)	0.0295 (10)	0.0235 (10)	−0.0007 (8)	0.0040 (8)	0.0012 (8)
C8	0.0372 (11)	0.0303 (11)	0.0266 (11)	−0.0027 (8)	0.0056 (8)	−0.0018 (8)
C9	0.0444 (12)	0.0292 (11)	0.0342 (12)	−0.0031 (9)	0.0046 (9)	0.0078 (9)
O3	0.0443 (8)	0.0397 (8)	0.0251 (8)	−0.0033 (6)	0.0097 (6)	0.0002 (6)
O4	0.0489 (9)	0.0328 (8)	0.0370 (8)	−0.0008 (6)	0.0108 (7)	0.0093 (6)
C10	0.0324 (10)	0.0344 (10)	0.0232 (10)	−0.0013 (9)	0.0044 (8)	0.0020 (9)
C11	0.0248 (9)	0.0339 (11)	0.0234 (10)	−0.0013 (8)	0.0019 (7)	0.0060 (8)
C12	0.0285 (10)	0.0308 (11)	0.0275 (11)	−0.0019 (8)	0.0020 (8)	0.0048 (8)
C13	0.0252 (10)	0.0396 (12)	0.0218 (10)	−0.0017 (8)	0.0027 (7)	0.0028 (8)
C14	0.0294 (10)	0.0383 (12)	0.0237 (10)	−0.0005 (8)	0.0051 (8)	0.0093 (9)
C15	0.0266 (10)	0.0320 (11)	0.0304 (11)	−0.0018 (8)	0.0023 (8)	0.0090 (9)
C16	0.0282 (10)	0.0339 (12)	0.0259 (11)	−0.0001 (8)	0.0025 (8)	0.0018 (8)
C17	0.0434 (12)	0.0404 (12)	0.0287 (12)	−0.0045 (10)	0.0078 (9)	−0.0043 (9)
C18	0.0412 (12)	0.0330 (12)	0.0423 (13)	−0.0009 (9)	0.0070 (10)	0.0054 (10)

Geometric parameters (Å, º) top

O1—C4	1.376 (2)	O3—C13	1.374 (2)
O1—C8	1.427 (2)	O3—C17	1.432 (2)
O2—C6	1.370 (2)	O4—C15	1.375 (2)
O2—C9	1.429 (2)	O4—C18	1.432 (2)
C1—C1ⁱ	1.328 (3)	C10—C10ⁱⁱ	1.326 (4)
C1—C2	1.469 (2)	C10—C11	1.470 (2)
C1—H1	0.9500	C10—H10	0.9500
C2—C7	1.383 (3)	C11—C16	1.392 (3)
C2—C3	1.405 (2)	C11—C12	1.401 (3)
C3—C4	1.379 (2)	C12—C13	1.389 (2)
C3—H3	0.9500	C12—H12	0.9500
C4—C5	1.395 (3)	C13—C14	1.384 (3)
C5—C6	1.390 (2)	C14—C15	1.382 (3)
C5—H5	0.9500	C14—H14	0.9500
C6—C7	1.394 (2)	C15—C16	1.394 (2)
C7—H7	0.9500	C16—H16	0.9500
C8—H8A	0.9800	C17—H17A	0.9800
C8—H8B	0.9800	C17—H17B	0.9800
C8—H8C	0.9800	C17—H17C	0.9800
C9—H9A	0.9800	C18—H18A	0.9800
C9—H9B	0.9800	C18—H18B	0.9800
C9—H9C	0.9800	C18—H18C	0.9800

C4—O1—C8	117.99 (13)	C13—O3—C17	117.61 (14)
C6—O2—C9	117.31 (15)	C15—O4—C18	116.97 (14)
C1ⁱ—C1—C2	126.9 (2)	C10ⁱⁱ—C10—C11	126.3 (2)
C1ⁱ—C1—H1	116.6	C10ⁱⁱ—C10—H10	116.9
C2—C1—H1	116.6	C11—C10—H10	116.9
C7—C2—C3	119.73 (16)	C16—C11—C12	119.91 (16)
C7—C2—C1	118.41 (16)	C16—C11—C10	117.89 (17)
C3—C2—C1	121.87 (16)	C12—C11—C10	122.19 (17)
C4—C3—C2	119.10 (17)	C13—C12—C11	119.14 (17)
C4—C3—H3	120.5	C13—C12—H12	120.4
C2—C3—H3	120.5	C11—C12—H12	120.4
O1—C4—C3	124.02 (16)	O3—C13—C14	115.15 (16)
O1—C4—C5	114.20 (15)	O3—C13—C12	123.76 (17)
C3—C4—C5	121.77 (16)	C14—C13—C12	121.09 (17)
C6—C5—C4	118.58 (16)	C15—C14—C13	119.63 (16)
C6—C5—H5	120.7	C15—C14—H14	120.2
C4—C5—H5	120.7	C13—C14—H14	120.2
O2—C6—C5	124.17 (16)	O4—C15—C14	116.03 (16)
O2—C6—C7	115.49 (16)	O4—C15—C16	123.58 (17)
C5—C6—C7	120.34 (17)	C14—C15—C16	120.38 (17)
C2—C7—C6	120.47 (17)	C11—C16—C15	119.84 (17)
C2—C7—H7	119.8	C11—C16—H16	120.1
C6—C7—H7	119.8	C15—C16—H16	120.1
O1—C8—H8A	109.5	O3—C17—H17A	109.5
O1—C8—H8B	109.5	O3—C17—H17B	109.5
H8A—C8—H8B	109.5	H17A—C17—H17B	109.5
O1—C8—H8C	109.5	O3—C17—H17C	109.5
H8A—C8—H8C	109.5	H17A—C17—H17C	109.5
H8B—C8—H8C	109.5	H17B—C17—H17C	109.5
O2—C9—H9A	109.5	O4—C18—H18A	109.5
O2—C9—H9B	109.5	O4—C18—H18B	109.5
H9A—C9—H9B	109.5	H18A—C18—H18B	109.5
O2—C9—H9C	109.5	O4—C18—H18C	109.5
H9A—C9—H9C	109.5	H18A—C18—H18C	109.5
H9B—C9—H9C	109.5	H18B—C18—H18C	109.5

C1ⁱ—C1—C2—C7	179.3 (2)	C10ⁱⁱ—C10—C11—C16	172.5 (2)
C1ⁱ—C1—C2—C3	−0.3 (3)	C10ⁱⁱ—C10—C11—C12	−6.9 (4)
C7—C2—C3—C4	−0.2 (3)	C16—C11—C12—C13	−0.2 (3)
C1—C2—C3—C4	179.35 (16)	C10—C11—C12—C13	179.18 (17)
C8—O1—C4—C3	−4.1 (2)	C17—O3—C13—C14	179.90 (16)
C8—O1—C4—C5	176.49 (15)	C17—O3—C13—C12	0.3 (3)
C2—C3—C4—O1	−179.24 (16)	C11—C12—C13—O3	179.04 (16)
C2—C3—C4—C5	0.2 (3)	C11—C12—C13—C14	−0.5 (3)
O1—C4—C5—C6	179.31 (15)	O3—C13—C14—C15	−178.83 (15)
C3—C4—C5—C6	−0.2 (3)	C12—C13—C14—C15	0.8 (3)
C9—O2—C6—C5	6.2 (3)	C18—O4—C15—C14	179.78 (16)
C9—O2—C6—C7	−173.96 (15)	C18—O4—C15—C16	−1.1 (3)
C4—C5—C6—O2	179.99 (16)	C13—C14—C15—O4	178.80 (16)
C4—C5—C6—C7	0.2 (3)	C13—C14—C15—C16	−0.3 (3)
C3—C2—C7—C6	0.2 (3)	C12—C11—C16—C15	0.6 (3)
C1—C2—C7—C6	−179.33 (16)	C10—C11—C16—C15	−178.75 (16)
O2—C6—C7—C2	179.95 (15)	O4—C15—C16—C11	−179.43 (16)
C5—C6—C7—C2	−0.2 (3)	C14—C15—C16—C11	−0.4 (3)

Symmetry codes: (i) −x, −y, −z+1; (ii) −x+1, −y+1, −z.

Experimental details

Crystal data
Chemical formula	C₁₈H₂₀O₄
M_r	300.34
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	100
a, b, c (Å)	7.1954 (3), 9.4203 (4), 22.6762 (5)
β (°)	93.783 (2)
V (Å³)	1533.71 (10)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.4 × 0.2 × 0.2

Data collection
Diffractometer	Nonius KappaCCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	7687, 3320, 2142
R_int	0.041
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.055, 0.150, 1.03
No. of reflections	3320
No. of parameters	207
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.24, −0.24

Computer programs: COLLECT (Hooft, 1998), DENZO (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SCHAKAL99 (Keller 1999), PLATON (Spek, 2009) and enCIFer (Allen et al., 2004).

References

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