1-(2-Methyl-5-phenyl-3-thien­yl)-2-(3-methyl-5-phenyl-2-thien­yl)-3,3,4,4,5,5-hexa­fluoro­cyclo­pent-1-ene: a novel photochromic hybrid diaryl­ethene

The title compound, C₂₇H₁₈F₆S₂, a novel photochromic hybrid diaryl­ethene derivative containing 2- and 3-thienyl substituents, is one of the most promising photochromic candidates with shorter wavelength for optical storage and other optoelectronic devices. In the crystal structure, the mol­ecule adopts a photoactive antiparallel conformation. The distance between the two reactive C atoms, i.e. the ring C atoms to which the methyl groups are attached, is 3.430 (4) Å. The dihedral angles between the thienyl and adjacent phenyl rings are 26.8 (2) and 33.98 (9)°.

S1. Comment

Photochromism is referred to as a photoinduced reversible transformation of a chemical species between two isomeric forms having different absorption spectra (Brown, 1971; Dürr & Bouas-Laurent, 1990). Photochromic compounds have attracted much attention because of their potential uses for optical memory, photo-optical switching and display devices (Takami & Irie, 2004). Of all the photochromic compounds, diarylethene derivatives are the most promising candidates for optical memories and other optoelectronic devices because of their good thermal stability, high sensitivity, fast response and high fatigue resistance (Irie, 2000; Tian & Yang, 2004). For application to a full color display and for increasing the optical storage density, it is indispensable to prepare red and yellow developing diarylethene derivatives (Takami & Irie, 2004). One approach to shorten the absorption wavelength of diarylethene is to attach thiophene rings to the ethene moiety at the 2-position (Uchida et al., 1998). For diarylethene, the absorption spectrum depends on the substituent and the π conjugation length. Compared with the closed-ring isomer bis(3-thienyl)ethane, where the π conjugation extends throughout the whole molecule, the π conjugation in the closed-ring isomer bis(2-thienyl)ethane is localized in a cyclohexadiene structure, so that it has a shorter absorption wavelength (Sun et al., 2003). Although many photochromic diarylethene have been reported, they are mainly symmetric diarylethene derivatives with both aryl substituents attached through either their 2- or 3-positions (Irie, 2000; Tian & Yang, 2004; Pu et al., 2004; Pu, Yang & Wang et al., 2005; Pu, Yang & Yan, 2005; Pu, Liu & Yan, 2005); diarylethenes with aryl substituents attached through a mixture of their 2- or 3-positions and which absorb at a short wavelength (400–500 nm) (Sun et al., 2003; Takami & Irie, 2004) are very rare. Therefore, it is desirable to develop diarylethene derivatives of this type for short wavelength memories. In the present paper, the structure of the title compound, 1-(2-methyl-5-phenyl-3-thienyl)-2-(3-methyl-5-phenyl-2-thienyl)-3,3,4,4,5,5- hexafluorocyclopent-1-ene, (Ia), is presented.

The molecule shows a photoactive anti-parallel conformation (Fig. 1). The two thiophene moieties are linked by the C1═C2 double bond, with the S1-containing thiophene ring attached to the ethylene moiety via the 2-position and the S2-containing thiophene ring attached via the 3-position. The two methyl groups are located on different sides of the double bond and are trans with repsect to the thiophene planes. Such a conformation is crucial for the compound to exhibit photochromic and photoinduced properties (Woodward & Hoffmann, 1970). The dihedral angle between the thiophene and adjacent benzene ring is 33.98 (9)° for the C10–C15 benzene ring and 26.8 (2)° for the C21–C26 benzene ring. The distance between the two reactive C atoms (C7···C17) is 3.430 (4) Å, which is short enough, theoretically, for the reaction to take place in the crystalline phase (Ramamurthy & Venkatesan, 1987).

In fact, the crystal of (Ia) shows photochromic reaction in accordance with the expected ring closure, forming (Ib) (see scheme). Upon irradiation with light of wavelength 254 nm, the colorless crystal of (Ia) rapidly turned red. When observed under polarized light, the intensity of the red color changed on rotation of the crystalline sample. This phenomenon suggested that the closed-ring isomers were regularly oriented in the crystal and that the photochromic reaction took place in the crystal lattice (Yamamoto et al., 2003). When the red crystal was dissolved in hexane, the solution turned red and the absorption maximum was observed at 501 nm, as for the closed-ring isomer (Ib). The red color of the crystal disappeared upon irradiation with light of wavelength 500 nm or daylight, and the absorption spectrum of the solution containing the colorless crystal was the same as that of the open-ring isomer (Ia), with the maximum absorption at 292 nm.

S2. Experimental

The novel title photochromic diarylethene (Ia) was derived originally from 2-methylthiophene, (1), and 3-methylthiophene, (6) (see reaction scheme). The reaction was carried out in six steps: (i) 3,5-dibromo-2-methylthiophene, (2) (50.7 g, 198.1 mmol), was obtained in 81.2% yield by bromizing (1) (24.0 g, 244.8 mmol) in acetic acid at 273 K; (ii) 3-bromo-2-methyl-5-thienylboronic acid, (3) (12.0 g, 54.3 mmol), was prepared in 85.5% yield in the presence of compound (2) (16.3 g, 63.7 mmol), n-BuLi/hexane solution (2.5 mol l⁻¹, 65 mmol) and tri-n-butylborate (18.8 ml, 68.9 mmol) at 195 K under a nitrogen atmosphere; (iii) 3-bromo-2-methyl-5-phenylthiophene, (4) (6.3 g, 24.9 mmol), was prepared in 70% yield by reacting (3) (7.8 g, 35.3 mmol) with 1-bromobenzene (5.6 g, 35.7 mmol) in the presence of Pd(PPh₃)₄ (0.9 g) and Na₂CO₃ (2 mol l⁻¹, 130 mmol) in tetrahydrofuran (THF, 120 ml) for 15 h at 343 K; (iv) (2-methyl-5-phenyl-3-thienyl)perfluorocyclopent-1-ene, (5) (2.4 g, 6.5 mmol), was synthesized in 53% yeild according to the procedure of Peters et al. (2003) from (4) (3.1 g, 12.3 mmol), n-BuLi/hexane solution (2.5 mol l⁻¹, 12.3 mmol) and perfluorocyclopentene (1.7 ml, 12.5 mmol); (v) 4-methyl-2-phenylthiophene, (7) (4.6 g, 26.4 mmol), was prepared in 67% yield by reacting (6) (3.9 g, 39.7 mmol) with 1-bromobenzene (6.2 g, 39.7 mmol) according to the procedure of Pu, Liu & Yan (2005); (vi) 2.8 ml of n-BuLi/hexane solution (2.5 mol l⁻¹, 7.0 mmol) was added slowly at 273 K under a nitrogen atmosphere to a stirred THF solution (50 ml) containing compound (7) (1.2 g, 6.9 mmol). After 30 min, compound (5) (2.4 g, 6.5 mmol) was added and the mixture was stirred for 3 h at this temperature. The reaction mixture was extracted with ether, evaporated in vacuo and purifed by column chromatography (hexane) to give the title compound (Ia) (1.9 g, 3.6 mmol) in 56% yield. Crystals of (Ia) were grown from a chloroform solution by slow evaporation (m.p. 403.2–403.5 K). Analysis calculated for C₂₇H₁₈F₆S₂ (%): C 62.30, H 3.49; found: C 62.44, H 3.57. ¹H NMR (400 MHz, CDCl₃): δ 1.794 (s, 3H), 2.014 (s, 3H), 7.073 (s, 1H, thiophene H), 7.284 (s, 1H, thiophene H), 7.301–7.341 (t, 2H, J = 8.0 Hz, benzene H), 7.369–7.407 (t, 4H, J = 7.6 Hz, benzene H), 7.543–7.587 (m, 4H, J = 8.8 Hz, benzene H). ¹⁹F NMR (400 MHz, CDCl₃): δ 109.33 (2 F), 109.50 (2 F), 131.42 (2 F).

S3. Refinement

Methyl H atoms were positioned geometrically (C—H = 0.96 Å) and refined as riding, with free rotation about the C—C bond and with U_iso(H) = 1.5U_eq(C). Ring-attached H atoms were also positioned geometrically (C—H = 0.93 Å) and were refined as riding, with U_iso(H) = 1.2U_eq(C).

Computing details

Data collection: XSCANS (Bruker, 1997); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXTL (Bruker, 1997); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Figures

Fig. 1. The structure of (Ia), drawn with 35% probability displacement ellipsoids, showing the atomic numbering scheme.

1-(2-Methyl-5-phenyl-3-thienyl)-2-(3-methyl-5-phenyl-2-thienyl)-3,3,4,4,5,5- hexafluorocyclopent-1-ene

Crystal data

C27H18F6S2	F(000) = 1064
Mr = 520.53	Dx = 1.449 Mg m^−3
Monoclinic, P21/c	Melting point = 403.2–403.5 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 11.5406 (12) Å	Cell parameters from 36 reflections
b = 9.2179 (7) Å	θ = 5.1–12.6°
c = 22.432 (2) Å	µ = 0.28 mm^−1
β = 90.263 (8)°	T = 295 K
V = 2386.3 (4) Å^3	Prism, colorless
Z = 4	0.6 × 0.5 × 0.4 mm

Data collection

Bruker P4 diffractometer	Rint = 0.028
Radiation source: fine-focus sealed tube	θmax = 25.0°, θmin = 1.8°
Graphite monochromator	h = −13→1
ω scans	k = −10→1
5525 measured reflections	l = −26→26
4201 independent reflections	3 standard reflections every 97 reflections
3121 reflections with I > 2σ(I)	intensity decay: none

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.054	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.112	H-atom parameters constrained
S = 1.02	w = 1/[σ^2(Fo^2) + (0.001P)^2 + 2.7P] where P = (Fo^2 + 2Fc^2)/3
4201 reflections	(Δ/σ)max < 0.001
318 parameters	Δρmax = 0.48 e Å^−3
0 restraints	Δρmin = −0.34 e Å^−3

Special details

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. The ride model of methyl H atoms is 137 through SHELXL sets the model 33 automatically. The parameters in the full-matrix least-square refinement are 318, which including 315 parameters (9 times 35 non-hydrogen atoms), two rotation parameters for two methyl groups and a overall scale factor.

The C4—F4 bond distance [1.306 (4) Å] is shorter than the other C-F distances [1.334 (4)–1.350 (4) Å], and the C4—C5 bond length [1.508 (5) Å] is shorter than the C3—C4 [1.534 (5) Å]. These variations in the bond lengths may correspond to low precision of the present study.

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 (Ų)

	x	y	z	Uiso*/Ueq
S1	0.43985 (8)	0.83464 (10)	0.08103 (4)	0.0710 (3)
S2	0.02356 (8)	0.87436 (12)	0.25513 (4)	0.0770 (3)
F1	−0.01608 (19)	1.1433 (3)	0.04472 (11)	0.1085 (8)
F2	0.0842 (3)	1.2709 (2)	0.10576 (10)	0.1125 (9)
F3	0.1261 (2)	1.1816 (4)	−0.03445 (10)	0.1261 (10)
F4	0.2209 (2)	1.3214 (2)	0.02240 (14)	0.1335 (11)
F5	0.2883 (3)	1.0098 (3)	−0.02831 (10)	0.1220 (10)
F6	0.3712 (2)	1.1345 (3)	0.04002 (13)	0.1186 (9)
C1	0.2282 (3)	0.9704 (3)	0.07132 (13)	0.0553 (7)
C2	0.1334 (3)	1.0228 (3)	0.09859 (12)	0.0530 (7)
C3	0.0910 (3)	1.1580 (4)	0.06841 (14)	0.0642 (8)
C4	0.1780 (3)	1.1906 (4)	0.01869 (15)	0.0683 (9)
C5	0.2691 (3)	1.0739 (4)	0.02420 (15)	0.0682 (9)
C6	0.2903 (3)	0.8341 (3)	0.08036 (13)	0.0581 (8)
C7	0.2463 (3)	0.6975 (4)	0.08751 (15)	0.0647 (8)
C8	0.3347 (3)	0.5899 (4)	0.09395 (14)	0.0688 (9)
H8A	0.3200	0.4914	0.0987	0.083*
C9	0.4449 (3)	0.6498 (4)	0.09227 (14)	0.0639 (8)
C10	0.5572 (3)	0.5742 (4)	0.09679 (14)	0.0659 (9)
C11	0.6526 (3)	0.6382 (4)	0.12324 (16)	0.0755 (10)
H11A	0.6464	0.7318	0.1384	0.091*
C12	0.7568 (3)	0.5660 (5)	0.12758 (18)	0.0905 (12)
H12A	0.8204	0.6104	0.1455	0.109*
C13	0.7661 (4)	0.4279 (6)	0.10528 (19)	0.1006 (15)
H13A	0.8361	0.3783	0.1084	0.121*
C14	0.6726 (4)	0.3624 (5)	0.07839 (19)	0.1029 (15)
H14A	0.6797	0.2692	0.0630	0.123*
C15	0.5675 (3)	0.4347 (4)	0.07413 (16)	0.0834 (11)
H15A	0.5041	0.3899	0.0562	0.100*
C16	0.1203 (3)	0.6570 (4)	0.08699 (19)	0.0873 (12)
H16A	0.0761	0.7337	0.0689	0.131*
H16B	0.0944	0.6423	0.1271	0.131*
H16C	0.1098	0.5692	0.0646	0.131*
C17	0.1244 (3)	0.9177 (4)	0.20208 (13)	0.0623 (8)
C18	0.0724 (2)	0.9715 (3)	0.15163 (13)	0.0542 (7)
C19	−0.0532 (2)	0.9804 (3)	0.15608 (13)	0.0549 (7)
H19A	−0.1017	1.0166	0.1264	0.066*
C20	−0.0910 (3)	0.9278 (4)	0.21046 (14)	0.0605 (8)
C21	−0.2111 (3)	0.9176 (4)	0.23147 (14)	0.0633 (8)
C22	−0.2444 (3)	0.8152 (4)	0.27343 (16)	0.0762 (10)
H22A	−0.1897	0.7510	0.2887	0.091*
C23	−0.3573 (3)	0.8074 (5)	0.29269 (18)	0.0913 (12)
H23A	−0.3777	0.7392	0.3213	0.110*
C24	−0.4394 (3)	0.8988 (6)	0.2702 (2)	0.0977 (14)
H24A	−0.5156	0.8927	0.2831	0.117*
C25	−0.4091 (3)	0.9981 (5)	0.2292 (2)	0.1023 (14)
H25A	−0.4653	1.0600	0.2137	0.123*
C26	−0.2953 (3)	1.0102 (4)	0.20939 (19)	0.0860 (11)
H26A	−0.2759	1.0804	0.1814	0.103*
C27	0.2497 (3)	0.8990 (5)	0.21745 (15)	0.0806 (11)
H27A	0.2951	0.9673	0.1952	0.121*
H27B	0.2737	0.8021	0.2077	0.121*
H27C	0.2610	0.9155	0.2593	0.121*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0640 (5)	0.0664 (5)	0.0827 (6)	0.0047 (4)	0.0102 (4)	0.0003 (5)
S2	0.0613 (5)	0.1065 (8)	0.0631 (5)	0.0027 (5)	0.0000 (4)	0.0155 (5)
F1	0.0784 (14)	0.132 (2)	0.1150 (18)	0.0029 (14)	−0.0168 (13)	0.0573 (16)
F2	0.200 (3)	0.0627 (13)	0.0751 (14)	0.0378 (16)	0.0216 (15)	−0.0033 (11)
F3	0.128 (2)	0.188 (3)	0.0627 (13)	0.033 (2)	−0.0066 (13)	0.0122 (16)
F4	0.144 (2)	0.0561 (14)	0.200 (3)	−0.0172 (15)	0.052 (2)	−0.0084 (16)
F5	0.205 (3)	0.0866 (16)	0.0744 (14)	0.0315 (18)	0.0553 (16)	0.0071 (12)
F6	0.0794 (15)	0.1096 (19)	0.167 (2)	−0.0234 (14)	−0.0012 (15)	0.0543 (18)
C1	0.0616 (18)	0.0500 (17)	0.0542 (16)	−0.0039 (15)	0.0012 (14)	−0.0016 (14)
C2	0.0607 (17)	0.0475 (17)	0.0507 (16)	−0.0003 (14)	−0.0046 (13)	−0.0030 (13)
C3	0.077 (2)	0.058 (2)	0.0582 (18)	0.0062 (17)	−0.0031 (16)	−0.0011 (16)
C4	0.090 (2)	0.053 (2)	0.062 (2)	−0.0079 (18)	−0.0040 (18)	0.0018 (16)
C5	0.077 (2)	0.061 (2)	0.066 (2)	−0.0050 (18)	0.0092 (17)	0.0000 (17)
C6	0.0598 (18)	0.0582 (19)	0.0564 (17)	0.0015 (15)	0.0040 (14)	−0.0036 (15)
C7	0.067 (2)	0.0544 (19)	0.073 (2)	0.0011 (16)	−0.0035 (16)	−0.0011 (16)
C8	0.062 (2)	0.070 (2)	0.075 (2)	0.0116 (17)	−0.0089 (16)	−0.0021 (18)
C9	0.072 (2)	0.062 (2)	0.0584 (18)	0.0123 (17)	−0.0006 (15)	−0.0051 (16)
C10	0.069 (2)	0.071 (2)	0.0572 (18)	0.0137 (18)	0.0036 (16)	0.0013 (16)
C11	0.073 (2)	0.076 (2)	0.078 (2)	0.0125 (19)	0.0024 (18)	0.0028 (19)
C12	0.073 (2)	0.114 (4)	0.085 (3)	0.019 (2)	−0.004 (2)	0.015 (3)
C13	0.094 (3)	0.123 (4)	0.085 (3)	0.050 (3)	0.011 (2)	0.011 (3)
C14	0.128 (4)	0.094 (3)	0.087 (3)	0.047 (3)	0.002 (3)	−0.013 (2)
C15	0.095 (3)	0.079 (3)	0.076 (2)	0.026 (2)	−0.007 (2)	−0.012 (2)
C16	0.076 (2)	0.058 (2)	0.128 (3)	−0.0043 (19)	−0.014 (2)	−0.002 (2)
C17	0.0571 (17)	0.075 (2)	0.0548 (17)	0.0040 (16)	−0.0003 (14)	0.0038 (16)
C18	0.0578 (17)	0.0507 (17)	0.0542 (16)	0.0020 (14)	−0.0036 (13)	−0.0016 (14)
C19	0.0537 (16)	0.0544 (18)	0.0567 (17)	−0.0011 (14)	0.0015 (13)	−0.0084 (14)
C20	0.0545 (17)	0.064 (2)	0.0631 (19)	0.0025 (15)	−0.0060 (14)	−0.0023 (16)
C21	0.0542 (17)	0.069 (2)	0.0665 (19)	0.0000 (16)	−0.0039 (15)	−0.0099 (17)
C22	0.062 (2)	0.089 (3)	0.077 (2)	−0.0048 (19)	0.0007 (17)	0.007 (2)
C23	0.068 (2)	0.118 (4)	0.088 (3)	−0.024 (2)	0.009 (2)	−0.003 (3)
C24	0.059 (2)	0.129 (4)	0.106 (3)	−0.005 (3)	0.009 (2)	−0.025 (3)
C25	0.067 (3)	0.107 (4)	0.133 (4)	0.023 (2)	−0.009 (3)	−0.010 (3)
C26	0.067 (2)	0.084 (3)	0.107 (3)	0.011 (2)	−0.001 (2)	0.002 (2)
C27	0.062 (2)	0.119 (3)	0.060 (2)	0.010 (2)	−0.0061 (16)	0.010 (2)

Geometric parameters (Å, º)

S1—C9	1.724 (3)	C13—C14	1.374 (6)
S1—C6	1.726 (3)	C13—H13A	0.9300
S2—C17	1.715 (3)	C14—C15	1.386 (5)
S2—C20	1.727 (3)	C14—H14A	0.9300
F1—C3	1.350 (4)	C15—H15A	0.9300
F2—C3	1.338 (4)	C16—H16A	0.9600
F3—C4	1.334 (4)	C16—H16B	0.9600
F4—C4	1.306 (4)	C16—H16C	0.9600
F5—C5	1.337 (4)	C17—C18	1.371 (4)
F6—C5	1.350 (4)	C17—C27	1.496 (4)
C1—C2	1.346 (4)	C18—C19	1.456 (4)
C1—C6	1.460 (4)	C19—C20	1.385 (4)
C1—C5	1.501 (4)	C19—H19A	0.9300
C2—C18	1.464 (4)	C20—C21	1.469 (4)
C2—C3	1.500 (4)	C21—C26	1.383 (5)
C3—C4	1.534 (5)	C21—C22	1.388 (5)
C4—C5	1.508 (5)	C22—C23	1.376 (5)
C6—C7	1.367 (4)	C22—H22A	0.9300
C7—C8	1.429 (4)	C23—C24	1.363 (6)
C7—C16	1.501 (5)	C23—H23A	0.9300
C8—C9	1.387 (4)	C24—C25	1.346 (6)
C8—H8A	0.9300	C24—H24A	0.9300
C9—C10	1.475 (4)	C25—C26	1.393 (5)
C10—C11	1.380 (5)	C25—H25A	0.9300
C10—C15	1.388 (5)	C26—H26A	0.9300
C11—C12	1.378 (5)	C27—H27A	0.9600
C11—H11A	0.9300	C27—H27B	0.9600
C12—C13	1.372 (6)	C27—H27C	0.9600
C12—H12A	0.9300
C9—S1—C6	91.82 (16)	C14—C13—H13A	119.8
C17—S2—C20	92.92 (15)	C13—C14—C15	120.3 (4)
C2—C1—C6	130.2 (3)	C13—C14—H14A	119.8
C2—C1—C5	110.5 (3)	C15—C14—H14A	119.8
C6—C1—C5	119.3 (3)	C14—C15—C10	119.7 (4)
C1—C2—C18	130.5 (3)	C14—C15—H15A	120.1
C1—C2—C3	110.9 (3)	C10—C15—H15A	120.1
C18—C2—C3	118.6 (3)	C7—C16—H16A	109.5
F2—C3—F1	105.6 (3)	C7—C16—H16B	109.5
F2—C3—C2	112.6 (3)	H16A—C16—H16B	109.5
F1—C3—C2	113.0 (3)	C7—C16—H16C	109.5
F2—C3—C4	110.1 (3)	H16A—C16—H16C	109.5
F1—C3—C4	109.5 (3)	H16B—C16—H16C	109.5
C2—C3—C4	106.1 (3)	C18—C17—C27	130.6 (3)
F4—C4—F3	106.4 (3)	C18—C17—S2	111.2 (2)
F4—C4—C5	112.9 (3)	C27—C17—S2	118.1 (2)
F3—C4—C5	109.8 (3)	C17—C18—C19	113.3 (3)
F4—C4—C3	112.6 (3)	C17—C18—C2	125.3 (3)
F3—C4—C3	110.2 (3)	C19—C18—C2	121.4 (3)
C5—C4—C3	105.0 (3)	C20—C19—C18	111.0 (3)
F5—C5—F6	105.4 (3)	C20—C19—H19A	124.5
F5—C5—C1	113.2 (3)	C18—C19—H19A	124.5
F6—C5—C1	110.8 (3)	C19—C20—C21	127.3 (3)
F5—C5—C4	111.2 (3)	C19—C20—S2	111.6 (2)
F6—C5—C4	109.5 (3)	C21—C20—S2	121.1 (2)
C1—C5—C4	106.8 (3)	C26—C21—C22	117.8 (3)
C7—C6—C1	128.8 (3)	C26—C21—C20	120.5 (3)
C7—C6—S1	111.9 (2)	C22—C21—C20	121.7 (3)
C1—C6—S1	119.2 (2)	C23—C22—C21	120.9 (4)
C6—C7—C8	112.7 (3)	C23—C22—H22A	119.6
C6—C7—C16	126.0 (3)	C21—C22—H22A	119.6
C8—C7—C16	121.3 (3)	C24—C23—C22	120.6 (4)
C9—C8—C7	112.0 (3)	C24—C23—H23A	119.7
C9—C8—H8A	124.0	C22—C23—H23A	119.7
C7—C8—H8A	124.0	C25—C24—C23	119.4 (4)
C8—C9—C10	128.0 (3)	C25—C24—H24A	120.3
C8—C9—S1	111.5 (2)	C23—C24—H24A	120.3
C10—C9—S1	120.4 (3)	C24—C25—C26	121.3 (4)
C11—C10—C15	119.0 (3)	C24—C25—H25A	119.3
C11—C10—C9	121.8 (3)	C26—C25—H25A	119.3
C15—C10—C9	119.3 (3)	C21—C26—C25	119.9 (4)
C12—C11—C10	121.2 (4)	C21—C26—H26A	120.1
C12—C11—H11A	119.4	C25—C26—H26A	120.1
C10—C11—H11A	119.4	C17—C27—H27A	109.5
C13—C12—C11	119.5 (4)	C17—C27—H27B	109.5
C13—C12—H12A	120.2	H27A—C27—H27B	109.5
C11—C12—H12A	120.2	C17—C27—H27C	109.5
C12—C13—C14	120.3 (4)	H27A—C27—H27C	109.5
C12—C13—H13A	119.8	H27B—C27—H27C	109.5
C6—C1—C2—C18	10.5 (5)	C6—S1—C9—C10	179.4 (3)
C5—C1—C2—C18	−170.9 (3)	C8—C9—C10—C11	−147.3 (4)
C6—C1—C2—C3	−171.9 (3)	S1—C9—C10—C11	35.1 (4)
C5—C1—C2—C3	6.8 (4)	C8—C9—C10—C15	32.4 (5)
C1—C2—C3—F2	−123.5 (3)	S1—C9—C10—C15	−145.2 (3)
C18—C2—C3—F2	54.5 (4)	C15—C10—C11—C12	−0.2 (5)
C1—C2—C3—F1	117.0 (3)	C9—C10—C11—C12	179.5 (3)
C18—C2—C3—F1	−65.0 (4)	C10—C11—C12—C13	0.0 (6)
C1—C2—C3—C4	−3.0 (3)	C11—C12—C13—C14	0.5 (6)
C18—C2—C3—C4	174.9 (3)	C12—C13—C14—C15	−0.7 (7)
F2—C3—C4—F4	−3.0 (4)	C13—C14—C15—C10	0.5 (6)
F1—C3—C4—F4	112.7 (3)	C11—C10—C15—C14	0.0 (5)
C2—C3—C4—F4	−125.1 (3)	C9—C10—C15—C14	−179.7 (4)
F2—C3—C4—F3	−121.6 (3)	C20—S2—C17—C18	0.0 (3)
F1—C3—C4—F3	−5.9 (4)	C20—S2—C17—C27	177.4 (3)
C2—C3—C4—F3	116.3 (3)	C20—S2—C17—C6	−88.3 (3)
F2—C3—C4—C5	120.2 (3)	C7—C6—C17—C18	−104.7 (3)
F1—C3—C4—C5	−124.1 (3)	C1—C6—C17—C18	30.7 (2)
C2—C3—C4—C5	−1.8 (3)	S1—C6—C17—C18	142.6 (2)
C2—C1—C5—F5	−130.5 (3)	C7—C6—C17—C27	101.9 (3)
C6—C1—C5—F5	48.3 (4)	C1—C6—C17—C27	−122.8 (3)
C2—C1—C5—F6	111.3 (3)	S1—C6—C17—C27	−10.9 (3)
C6—C1—C5—F6	−69.9 (4)	C7—C6—C17—S2	−5.8 (4)
C2—C1—C5—C4	−7.8 (4)	C1—C6—C17—S2	129.5 (4)
C6—C1—C5—C4	171.0 (3)	S1—C6—C17—S2	−118.5 (3)
F4—C4—C5—F5	−107.5 (4)	C27—C17—C18—C19	−176.0 (4)
F3—C4—C5—F5	11.0 (4)	S2—C17—C18—C19	0.9 (4)
C3—C4—C5—F5	129.5 (3)	C6—C17—C18—C19	151.1 (3)
F4—C4—C5—F6	8.5 (4)	C27—C17—C18—C2	1.2 (6)
F3—C4—C5—F6	127.1 (3)	S2—C17—C18—C2	178.2 (2)
C3—C4—C5—F6	−114.4 (3)	C6—C17—C18—C2	−31.7 (3)
F4—C4—C5—C1	128.5 (3)	C1—C2—C18—C17	38.9 (5)
F3—C4—C5—C1	−112.9 (3)	C3—C2—C18—C17	−138.6 (3)
C3—C4—C5—C1	5.5 (3)	C1—C2—C18—C19	−144.0 (3)
C2—C1—C6—C7	43.7 (5)	C3—C2—C18—C19	38.5 (4)
C5—C1—C6—C7	−134.8 (4)	C17—C18—C19—C20	−1.7 (4)
C2—C1—C6—S1	−138.0 (3)	C2—C18—C19—C20	−179.0 (3)
C5—C1—C6—S1	43.5 (4)	C18—C19—C20—C21	−179.5 (3)
C2—C1—C6—C17	−20.2 (3)	C18—C19—C20—S2	1.6 (3)
C5—C1—C6—C17	161.3 (3)	C17—S2—C20—C19	−1.0 (3)
C9—S1—C6—C7	−0.9 (3)	C17—S2—C20—C21	−180.0 (3)
C9—S1—C6—C1	−179.5 (2)	C19—C20—C21—C26	−26.0 (5)
C9—S1—C6—C17	97.38 (19)	S2—C20—C21—C26	152.8 (3)
C1—C6—C7—C8	178.6 (3)	C19—C20—C21—C22	153.6 (3)
S1—C6—C7—C8	0.2 (4)	S2—C20—C21—C22	−27.7 (5)
C17—C6—C7—C8	−124.0 (3)	C26—C21—C22—C23	−0.6 (5)
C1—C6—C7—C16	0.6 (6)	C20—C21—C22—C23	179.9 (3)
S1—C6—C7—C16	−177.8 (3)	C21—C22—C23—C24	1.0 (6)
C17—C6—C7—C16	58.0 (4)	C22—C23—C24—C25	−0.5 (7)
C6—C7—C8—C9	0.9 (4)	C23—C24—C25—C26	−0.4 (7)
C16—C7—C8—C9	179.0 (3)	C22—C21—C26—C25	−0.3 (6)
C7—C8—C9—C10	−179.3 (3)	C20—C21—C26—C25	179.2 (4)
C7—C8—C9—S1	−1.5 (4)	C24—C25—C26—C21	0.9 (7)
C6—S1—C9—C8	1.4 (3)