organic compounds
cis,trans,cis-1,2,3,4-Tetrakis[2-(ethylsulfanyl)phenyl]cyclobutane
aInstitute of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9/163, A-1060 Vienna, Austria, and bInstitute for Chemical Technologies and Analytics, Division of Structural Chemistry, TU Wien, Getreidemarkt 9/164-SC, A-1060 Vienna, Austria
*Correspondence e-mail: matthias.weil@tuwien.ac.at
The title cyclobutane derivative, C36H40S4, formed serendipitously through a photochemically initiated [2 + 2] cycloaddition. The contains half a molecule with the 2-(ethylsulfanyl)phenyl substituents in a cis configuration, the other half of the molecule being generated by the application of a twofold rotation operation. The substituents in both halves of the molecules are in a trans arrangement relative to each other. The cyclobutane ring shows angular and torsional strains, with C—C—C bond angles of 89.80 (8) and 88.40 (8)°, and an average absolute torsion angle of 14.28 (10)°. The angle of pucker in the ring is 20.27 (12)°. The Ccb—Ccb—Cb angles between the cyclobutane (cb) ring atoms and the attached benzene (b) ring atoms are widened and range from 115.19 (10) to 121.66 (10)°. A weak intramolecular C—H⋯S hydrogen-bonding interaction between one of the cyclobutane ring H atoms and the S atom may help to establish the molecular conformation. No specific intermolecular interactions are found.
Keywords: crystal structure; cyclobutane; sulfide; conformation; [2 + 2] cycloaddition.
CCDC reference: 1443096
Structure description
The title compound was obtained from a bis-thioethyl-substituted stilbene by an unintentional [2 + 2] cycloaddition (Figs. 1 and 2). A weak intramolecular C—H⋯S hydrogen-bonding interaction between one of the cyclobutane ring H atoms and the S atom may help to establish the molecular conformation ((Fig. 3 and Table 1). The stilbene was synthesized as a model compound for thioalkyl-substituted poly(p-phenylene vinylene) (PPV). PPVs were among the first materials applied in organic solar cells as well as organic LEDs and have become one of the materials of choice for studies on the basic photophysics of conjugated polymers (Blayney et al., 2014). For synthetic details, see: Diéguez et al. (2010); Tzur et al. (2010). For a review on conformations and configurations of cyclobutanes, see: Berg (2005).
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Synthesis and crystallization
The reaction pathway involving compounds 1–3 and the originally intended reaction product 4 are schematically shown (Fig. 1). The synthesis of stilbene 2 was carried out following a McMurry reaction protocol of Diéguez et al. (2010). Zinc (2.94 g, 45 mmol) and titanocene dichloride (5.60 g, 22.5 mmol) were dissolved in 40 ml dry, degassed tetrahydrofuran under argon atmosphere. The solution was stirred for 5 min and aldehyde 1 (2.49 g, 15 mmol), which was prepared by a modified procedure of Tzur et al. (2010), was added to the reaction mixture as a solution in 30 ml dry, degassed tetrahydrofuran. The reaction was heated to reflux for 3 h, cooled to room temperature and quenched with 30 ml diisopropyl ether. The solvent was evaporated in vacuo, the residue was dissolved in dichloromethane and washed with 1M HCl and brine. The organic layer was then dried over anhydrous sodium sulfate and the solvent was again evaporated in vacuo. The resulting dark-orange oil was purified by using silica gel as and a petroleum ether:dichloromethane mixture (5:1 to 3:1 v/v) as A second column using aluminum oxide yielded 2 as a colorless oil (0.88 g, 2.9 mmol, 39%). Storage of 2 at room temperature and without light protection resulted in the quantitative formation of crystals of the title compound 3 in the form of translucent blocks within two weeks. 1H NMR (CDCl3, 200 MHz): δ = 7.41–7.32 (m, 4H), 7.21– 7.13 (m, 4H), 7.09–6.98 (m, 8H), 5.01 (s, 4H), 2.87–2.59 (m, 8H), 1.16 (t, 12H, J = 7.5 Hz) p.p.m. 13C NMR (APT) (CDCl3, 50 MHz): δ = 140.1 (s), 136.9 (s), 128.9 (d), 127.6 (d), 126.4 (d), 125.3 (d), 44.8 (d), 28.3 (t), 14.2 (q) p.p.m.
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2Structural data
CCDC reference: 1443096
10.1107/S2414314615024268/hb4001sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S2414314615024268/hb4001Isup2.hkl
Supporting information file. DOI: 10.1107/S2414314615024268/hb4001Isup3.cml
The reaction pathway involving compounds 1 - 3 and the originally intended reaction product 4 are schematically shown (Fig. 1). The synthesis of stilbene 2 was carried out following a McMurry reaction protocol of Diéguez et al. (2010). Zinc (2.94 g, 45 mmol) and titanocene dichloride (5.60 g, 22.5 mmol) were dissolved in 40 ml dry, degassed tetrahydrofuran under argon atmosphere. The solution was stirred for 5 min and aldehyde 1 (2.49 g, 15 mmol), which was prepared by a modified procedure of Tzur et al. (2010), was added to the reaction mixture as a solution in 30 ml dry, degassed tetrahydrofuran. The reaction was heated to reflux for 3 h, cooled to room temperature and quenched with 30 ml diisopropyl ether. The solvent was evaporated in vacuo, the residue was dissolved in dichloromethane and washed with 1 N HCl and brine. The organic layer was then dried over anhydrous sodium sulfate and the solvent was again evaporated in vacuo. The resulting dark orange oil was purified by δ = 7.41 − 7.32 (m, 4H), 7.21 − 7.13 (m, 4H), 7.09 − 6.98 (m, 8H), 5.01 (s, 4H), 2.87 − 2.59 (m, 8H), 1.16 (t, 12H, J = 7.5 Hz) p.p.m. 13C NMR (APT) (CDCl3, 50 MHz): δ = 140.1 (s), 136.9 (s), 128.9 (d), 127.6 (d), 126.4 (d), 125.3 (d), 44.8 (d), 28.3 (t), 14.2 (q) p.p.m.
using silica gel as and a petrol ether:dichloromethane mixture (5:1 to 3:1 v/v) as A second column using aluminium oxide yielded 2 as a colorless oil (0.88 g, 2.9 mmol, 39%). Storage of 2 at room temperature and without light protection resulted in the quantitative formation of crystals of the title compound 3 in the form of translucent blocks within two weeks. 1H NMR (CDCl3, 200 MHz):The reaction pathway involving compounds 1–3 and the originally intended reaction product 4 are schematically shown (Fig. 1). The synthesis of stilbene 2 was carried out following a McMurry reaction protocol of Diéguez et al. (2010). Zinc (2.94 g, 45 mmol) and titanocene dichloride (5.60 g, 22.5 mmol) were dissolved in 40 ml dry, degassed tetrahydrofuran under argon atmosphere. The solution was stirred for 5 min and aldehyde 1 (2.49 g, 15 mmol), which was prepared by a modified procedure of Tzur et al. (2010), was added to the reaction mixture as a solution in 30 ml dry, degassed tetrahydrofuran. The reaction was heated to reflux for 3 h, cooled to room temperature and quenched with 30 ml diisopropyl ether. The solvent was evaporated in vacuo, the residue was dissolved in dichloromethane and washed with 1N HCl and brine. The organic layer was then dried over anhydrous sodium sulfate and the solvent was again evaporated in vacuo. The resulting dark-orange oil was purified by δ = 7.41–7.32 (m, 4H), 7.21– 7.13 (m, 4H), 7.09–6.98 (m, 8H), 5.01 (s, 4H), 2.87–2.59 (m, 8H), 1.16 (t, 12H, J = 7.5 Hz) p.p.m. 13C NMR (APT) (CDCl3, 50 MHz): δ = 140.1 (s), 136.9 (s), 128.9 (d), 127.6 (d), 126.4 (d), 125.3 (d), 44.8 (d), 28.3 (t), 14.2 (q) p.p.m.
using silica gel as and a petrol ether:dichloromethane mixture (5:1 to 3:1 v/v) as A second column using aluminium oxide yielded 2 as a colorless oil (0.88 g, 2.9 mmol, 39%). Storage of 2 at room temperature and without light protection resulted in the quantitative formation of crystals of the title compound 3 in the form of translucent blocks within two weeks. 1H NMR (CDCl3, 200 MHz):H atoms were placed in calculated positions and were refined in the riding atom approximation, with Uiso(H) = 1.2Ueq(C).
The title compound was obtained from a bis-thioethyl substituted stilbene by an unintentional [2 + 2]
The stilbene was synthesized as a model compound for thioalkyl-substituted poly(p-phenylene vinylene) (PPV). PPVs were among the first materials applied in organic solar cells as well as organic LEDs and have become one of the materials of choice for studies on the basic photophysics of conjugated polymers (Blayney et al., 2014). For synthetic details, see: Diéguez et al. (2010); Tzur et al. (2010). For a review on conformations and configurations of cyclobutanes, see: Berg (2005).Data collection: APEX2 (Bruker, 2014); cell
SAINT (Bruker, 2014); data reduction: SAINT (Bruker, 2014); program(s) used to solve structure: SUPERFLIP (Palatinus & Chapuis, 2007); program(s) used to refine structure: JANA2006 (Petříček et al., 2014); molecular graphics: XP in SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006); software used to prepare material for publication: publCIF (Westrip, 2010).Fig. 1. Reaction scheme to obtain the title compound (top) and the originally intended product (bottom). | |
Fig. 2. The molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level; H atoms are given as spheres of arbitrary radius. Non-labelled atoms are generated by symmetry code −x + 2, y, −z + 1/2. | |
Fig. 3. The packing of the molecules in the crystal structure of the title compound in a view along [100]. |
C36H40S4 | F(000) = 1280 |
Mr = 600.92 | Dx = 1.278 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 9001 reflections |
a = 11.2972 (8) Å | θ = 2.9–32.6° |
b = 13.0708 (10) Å | µ = 0.33 mm−1 |
c = 21.3833 (17) Å | T = 100 K |
β = 98.400 (2)° | Block, translucent colourless |
V = 3123.7 (4) Å3 | 0.65 × 0.62 × 0.48 mm |
Z = 4 |
Bruker APEXII CCD diffractometer | 5518 independent reflections |
Radiation source: X-ray tube | 4606 reflections with I > 3σ(I) |
Graphite monochromator | Rint = 0.023 |
ω and φ–scans | θmax = 32.6°, θmin = 1.9° |
Absorption correction: multi-scan (SADABS; Bruker, 2014) | h = −17→17 |
Tmin = 0.80, Tmax = 0.88 | k = −19→19 |
31669 measured reflections | l = −32→32 |
Refinement on F | 80 constraints |
R[F2 > 2σ(F2)] = 0.041 | H-atom parameters constrained |
wR(F2) = 0.058 | Weighting scheme based on measured s.u.'s w = 1/(σ2(F) + 0.0001F2) |
S = 3.21 | (Δ/σ)max = 0.019 |
5518 reflections | Δρmax = 0.57 e Å−3 |
181 parameters | Δρmin = −0.51 e Å−3 |
0 restraints |
C36H40S4 | V = 3123.7 (4) Å3 |
Mr = 600.92 | Z = 4 |
Monoclinic, C2/c | Mo Kα radiation |
a = 11.2972 (8) Å | µ = 0.33 mm−1 |
b = 13.0708 (10) Å | T = 100 K |
c = 21.3833 (17) Å | 0.65 × 0.62 × 0.48 mm |
β = 98.400 (2)° |
Bruker APEXII CCD diffractometer | 5518 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2014) | 4606 reflections with I > 3σ(I) |
Tmin = 0.80, Tmax = 0.88 | Rint = 0.023 |
31669 measured reflections |
R[F2 > 2σ(F2)] = 0.041 | 0 restraints |
wR(F2) = 0.058 | H-atom parameters constrained |
S = 3.21 | Δρmax = 0.57 e Å−3 |
5518 reflections | Δρmin = −0.51 e Å−3 |
181 parameters |
x | y | z | Uiso*/Ueq | ||
S1 | 0.87910 (3) | 0.00251 (3) | 0.077753 (15) | 0.01809 (10) | |
S2 | 0.95635 (3) | −0.26468 (3) | 0.105586 (15) | 0.01571 (9) | |
C1 | 0.97736 (10) | 0.02697 (9) | 0.21431 (5) | 0.0109 (3) | |
C2 | 0.99420 (11) | −0.09281 (9) | 0.21282 (5) | 0.0111 (3) | |
C3 | 1.03225 (11) | 0.09664 (9) | 0.17023 (6) | 0.0122 (3) | |
C4 | 0.99249 (11) | 0.09175 (9) | 0.10458 (6) | 0.0135 (3) | |
C5 | 1.04055 (12) | 0.15814 (10) | 0.06346 (6) | 0.0183 (4) | |
C6 | 1.12381 (12) | 0.23133 (11) | 0.08726 (7) | 0.0204 (4) | |
C7 | 1.16082 (12) | 0.23866 (10) | 0.15155 (7) | 0.0196 (4) | |
C8 | 1.11571 (11) | 0.17117 (10) | 0.19249 (6) | 0.0155 (3) | |
C9 | 1.10217 (10) | −0.13204 (9) | 0.18639 (6) | 0.0118 (3) | |
C10 | 1.09395 (11) | −0.20633 (10) | 0.13841 (6) | 0.0133 (3) | |
C11 | 1.19725 (13) | −0.23932 (10) | 0.11493 (6) | 0.0176 (4) | |
C12 | 1.30895 (12) | −0.20113 (10) | 0.13908 (7) | 0.0193 (4) | |
C13 | 1.31825 (12) | −0.12954 (10) | 0.18711 (7) | 0.0187 (4) | |
C14 | 1.21622 (11) | −0.09526 (10) | 0.20995 (6) | 0.0158 (4) | |
C15 | 0.81195 (12) | 0.05410 (11) | 0.00215 (6) | 0.0201 (4) | |
C16 | 0.69192 (16) | 0.00156 (14) | −0.01675 (8) | 0.0362 (5) | |
C17 | 0.95165 (12) | −0.36869 (10) | 0.16180 (6) | 0.0197 (4) | |
C18 | 1.05717 (13) | −0.44112 (11) | 0.16675 (9) | 0.0311 (5) | |
H1c1 | 0.901213 | 0.056516 | 0.198149 | 0.013* | |
H1c2 | 0.936693 | −0.134784 | 0.187075 | 0.0133* | |
H1c5 | 1.015758 | 0.15293 | 0.018686 | 0.0219* | |
H1c6 | 1.155904 | 0.277157 | 0.058921 | 0.0244* | |
H1c7 | 1.217541 | 0.290186 | 0.167956 | 0.0235* | |
H1c8 | 1.142779 | 0.176151 | 0.237076 | 0.0186* | |
H1c11 | 1.19035 | −0.289135 | 0.0816 | 0.0212* | |
H1c12 | 1.379047 | −0.224093 | 0.122669 | 0.0231* | |
H1c13 | 1.395355 | −0.10342 | 0.204747 | 0.0224* | |
H1c14 | 1.224302 | −0.04479 | 0.242917 | 0.0189* | |
H1c15 | 0.799702 | 0.12634 | 0.006158 | 0.0241* | |
H2c15 | 0.863011 | 0.040274 | −0.029004 | 0.0241* | |
H1c16 | 0.657192 | 0.024312 | −0.058067 | 0.0435* | |
H2c16 | 0.703434 | −0.071188 | −0.01731 | 0.0435* | |
H3c16 | 0.63938 | 0.018387 | 0.013187 | 0.0435* | |
H1c17 | 0.945536 | −0.340933 | 0.202767 | 0.0237* | |
H2c17 | 0.878734 | −0.406582 | 0.151001 | 0.0237* | |
H1c18 | 1.045087 | −0.496526 | 0.194607 | 0.0374* | |
H2c18 | 1.0643 | −0.467761 | 0.125628 | 0.0374* | |
H3c18 | 1.129027 | −0.40502 | 0.183155 | 0.0374* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.02583 (19) | 0.01681 (17) | 0.01032 (15) | −0.00304 (13) | −0.00175 (12) | 0.00162 (11) |
S2 | 0.01991 (17) | 0.01504 (16) | 0.01128 (14) | −0.00217 (12) | −0.00074 (12) | −0.00097 (11) |
C1 | 0.0103 (5) | 0.0125 (5) | 0.0098 (5) | 0.0012 (5) | 0.0014 (4) | 0.0000 (4) |
C2 | 0.0115 (5) | 0.0123 (6) | 0.0092 (5) | −0.0010 (4) | 0.0004 (4) | −0.0008 (4) |
C3 | 0.0122 (5) | 0.0129 (6) | 0.0120 (5) | 0.0029 (5) | 0.0038 (4) | 0.0003 (4) |
C4 | 0.0166 (6) | 0.0134 (6) | 0.0110 (5) | 0.0024 (5) | 0.0035 (4) | −0.0001 (4) |
C5 | 0.0250 (7) | 0.0187 (6) | 0.0125 (6) | 0.0033 (5) | 0.0074 (5) | 0.0022 (5) |
C6 | 0.0224 (7) | 0.0193 (7) | 0.0214 (6) | 0.0003 (6) | 0.0101 (5) | 0.0056 (5) |
C7 | 0.0187 (6) | 0.0175 (7) | 0.0231 (7) | −0.0042 (5) | 0.0049 (5) | 0.0023 (5) |
C8 | 0.0156 (6) | 0.0162 (6) | 0.0146 (6) | 0.0003 (5) | 0.0022 (5) | 0.0008 (5) |
C9 | 0.0130 (6) | 0.0111 (6) | 0.0117 (5) | 0.0005 (5) | 0.0027 (4) | 0.0015 (4) |
C10 | 0.0175 (6) | 0.0122 (6) | 0.0106 (5) | −0.0006 (5) | 0.0030 (4) | 0.0013 (4) |
C11 | 0.0235 (7) | 0.0146 (6) | 0.0163 (6) | 0.0021 (5) | 0.0082 (5) | 0.0002 (5) |
C12 | 0.0178 (6) | 0.0177 (6) | 0.0245 (7) | 0.0048 (5) | 0.0105 (5) | 0.0043 (5) |
C13 | 0.0120 (6) | 0.0175 (6) | 0.0271 (7) | 0.0003 (5) | 0.0050 (5) | 0.0022 (5) |
C14 | 0.0145 (6) | 0.0147 (6) | 0.0180 (6) | −0.0001 (5) | 0.0024 (5) | −0.0022 (5) |
C15 | 0.0290 (7) | 0.0199 (7) | 0.0106 (5) | 0.0004 (6) | 0.0001 (5) | 0.0012 (5) |
C16 | 0.0430 (10) | 0.0410 (10) | 0.0196 (7) | −0.0122 (8) | −0.0125 (7) | 0.0072 (7) |
C17 | 0.0197 (7) | 0.0189 (7) | 0.0198 (6) | −0.0047 (5) | 0.0004 (5) | 0.0044 (5) |
C18 | 0.0253 (8) | 0.0228 (8) | 0.0443 (10) | −0.0013 (7) | 0.0018 (7) | 0.0133 (7) |
S1—C4 | 1.7652 (13) | C11—C12 | 1.3849 (19) |
S2—C10 | 1.7810 (13) | C11—H1c11 | 0.96 |
C1—C1i | 1.5373 (16) | C12—C13 | 1.382 (2) |
C1—C3 | 1.5076 (18) | C12—H1c12 | 0.96 |
C1—H1c1 | 0.96 | C13—C14 | 1.3901 (19) |
C2—C9 | 1.5072 (18) | C13—H1c13 | 0.96 |
C2—H1c2 | 0.96 | C14—H1c14 | 0.96 |
C3—C4 | 1.4115 (17) | C15—C16 | 1.521 (2) |
C3—C8 | 1.3905 (17) | C15—H1c15 | 0.96 |
C4—C5 | 1.4000 (19) | C15—H2c15 | 0.96 |
C5—C6 | 1.3852 (19) | C16—H1c16 | 0.96 |
C5—H1c5 | 0.96 | C16—H2c16 | 0.96 |
C6—C7 | 1.381 (2) | C16—H3c16 | 0.96 |
C6—H1c6 | 0.96 | C17—C18 | 1.514 (2) |
C7—C8 | 1.391 (2) | C17—H1c17 | 0.96 |
C7—H1c7 | 0.96 | C17—H2c17 | 0.96 |
C8—H1c8 | 0.96 | C18—H1c18 | 0.96 |
C9—C10 | 1.4057 (17) | C18—H2c18 | 0.96 |
C9—C14 | 1.3983 (17) | C18—H3c18 | 0.96 |
C10—C11 | 1.404 (2) | ||
C1i—C1—C3 | 120.87 (10) | C10—C11—H1c11 | 119.48 |
C1i—C1—H1c1 | 120.54 | C12—C11—H1c11 | 119.48 |
C3—C1—H1c1 | 87.75 | C11—C12—C13 | 119.17 (13) |
C9—C2—H1c2 | 96.17 | C11—C12—H1c12 | 120.41 |
C1—C3—C4 | 119.63 (10) | C13—C12—H1c12 | 120.41 |
C1—C3—C8 | 121.97 (11) | C12—C13—C14 | 120.16 (12) |
C4—C3—C8 | 118.26 (11) | C12—C13—H1c13 | 119.92 |
S1—C4—C3 | 117.61 (9) | C14—C13—H1c13 | 119.92 |
S1—C4—C5 | 122.35 (9) | C9—C14—C13 | 122.02 (12) |
C3—C4—C5 | 120.01 (11) | C9—C14—H1c14 | 118.99 |
C4—C5—C6 | 120.15 (12) | C13—C14—H1c14 | 118.99 |
C4—C5—H1c5 | 119.93 | C16—C15—H1c15 | 109.47 |
C6—C5—H1c5 | 119.93 | C16—C15—H2c15 | 109.47 |
C5—C6—C7 | 120.28 (13) | H1c15—C15—H2c15 | 110.86 |
C5—C6—H1c6 | 119.86 | C15—C16—H1c16 | 109.47 |
C7—C6—H1c6 | 119.86 | C15—C16—H2c16 | 109.47 |
C6—C7—C8 | 119.82 (12) | C15—C16—H3c16 | 109.47 |
C6—C7—H1c7 | 120.09 | H1c16—C16—H2c16 | 109.47 |
C8—C7—H1c7 | 120.09 | H1c16—C16—H3c16 | 109.47 |
C3—C8—C7 | 121.43 (12) | H2c16—C16—H3c16 | 109.47 |
C3—C8—H1c8 | 119.29 | C18—C17—H1c17 | 109.47 |
C7—C8—H1c8 | 119.29 | C18—C17—H2c17 | 109.47 |
C2—C9—C10 | 122.54 (10) | H1c17—C17—H2c17 | 103.93 |
C2—C9—C14 | 120.10 (11) | C17—C18—H1c18 | 109.47 |
C10—C9—C14 | 117.37 (11) | C17—C18—H2c18 | 109.47 |
S2—C10—C9 | 122.98 (10) | C17—C18—H3c18 | 109.47 |
S2—C10—C11 | 116.79 (9) | H1c18—C18—H2c18 | 109.47 |
C9—C10—C11 | 120.22 (11) | H1c18—C18—H3c18 | 109.47 |
C10—C11—C12 | 121.03 (12) | H2c18—C18—H3c18 | 109.47 |
Symmetry code: (i) −x+2, y, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C36H40S4 |
Mr | 600.92 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 100 |
a, b, c (Å) | 11.2972 (8), 13.0708 (10), 21.3833 (17) |
β (°) | 98.400 (2) |
V (Å3) | 3123.7 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.33 |
Crystal size (mm) | 0.65 × 0.62 × 0.48 |
Data collection | |
Diffractometer | Bruker APEXII CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2014) |
Tmin, Tmax | 0.80, 0.88 |
No. of measured, independent and observed [I > 3σ(I)] reflections | 31669, 5518, 4606 |
Rint | 0.023 |
(sin θ/λ)max (Å−1) | 0.758 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.041, 0.058, 3.21 |
No. of reflections | 5518 |
No. of parameters | 181 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.57, −0.51 |
Computer programs: APEX2 (Bruker, 2014), SAINT (Bruker, 2014), SUPERFLIP (Palatinus & Chapuis, 2007), JANA2006 (Petříček et al., 2014), XP in SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006), publCIF (Westrip, 2010).
Acknowledgements
The X-ray centre of TU Wien is acknowledged for providing access to the single-crystal diffractometer.
References
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