Analysis of geometric parameters and packing considerations for triphenylboroxine derivatives, with tris(penta­fluoro­phen­yl)boroxine as an example

Mol­ecules of the title compound [systematic name: 2,4,6-(penta­fluorophenyl)-1,3,5,2,4,6-trioxatriborinane], C₁₈B₃F₁₅O₃, are located on crystallographic twofold rotation axes which run through the boroxine and one of the penta­fluoro­phenyl rings. The boroxine ring (r.m.s. deviation = 0.027 Å) and the penta­fluoro­phenyl rings (r.m.s. deviations = 0.004 and 0.001 Å) are essentially planar. The dihedral angles between the boroxine and the two symmetry-independent benzene rings are 8.64 (10) and 8.74 (12)°. The two benzene rings are mutually coparallel [dihedral angle = 0.80 (11)°]. The packing shows planes of mol­ecules parallel to (01), with an inter­planar spacing of 2.99 Å. Within these planes, all the mol­ecules are oriented in the same direction, whereas in neighbouring planes the direction is inverted. Short B...F contacts of 3.040 (2) and 3.1624 (12) Å occur between planes. The geometric parameters of the boroxine ring in the title compound agree well with those of comparable boroxine structures, while the packing reveals some striking similarities and differences.

S1. Comment

It has been known for decades that the Si—Si bond in halosubstituted disilanes can be cleaved in the presence of a Lewis base (Meyer-Wegner et al., 2011). The reactivity of Si₂Cl₆ has been studied mostly with a focus on its behaviour towards neutral N and P donors, yet some reactions of Si₂Cl₆ with anionic nucleophiles have also been described (Meyer-Wegner et al., 2009). Recently, we have discovered that the reaction of Si₂Cl₆ with two equivalents of Na[SitBu₃] (Lerner, 2005) leads to several products such as neopentasilane Si₅Cl₁₂ and the tetrasilatetrahedrane Si₄(SitBu₃)₄ (Meyer-Wegner et al., 2009), but no substitution product [(tBu₃Si)SiCl₂SiCl₂(SitBu₃); Bolte & Lerner 2011] was formed thereby. The title boroxine, (I), was obtained by the reaction of the Lewis acid tris(pentafluorophenyl)borane monohydrate with Si₂Cl₆. In this study, we describe the molecular and crystal structure of (I). Single crystals were isolated from the reaction solution on cooling from 453 K to room temperature.

Boronic acids, RB(OH)₂ (R = alkyl or aryl), can be readily converted to the corresponding boroxines, (RBO)₃. Although the B centres in boroxines possess a higher Lewis acidity than the C atoms in arenes, X-ray structure analysis provides evidence for the existence of a π-ring system in boroxines. Owing to significant differences in both the steric and electronic properties of the ligands of boroxines, different crystal-packing patterns have been found in their crystal structures (Boese et al., 1987).

The molecule of (I) (Fig. 1) is located on a crystallographic twofold rotation axis running through the boroxine ring and one of the pentafluorophenyl rings. The boroxine (r.m.s. deviation = 0.027 Å) and pentafluorophenyl rings (r.m.s. deviations = 0.004 and 0.001 Å) are essentially planar. The dihedral angles between the boroxine ring and the two symmetry-independent benzene rings are 8.64 (10) and 8.74 (12)°. The two benzene rings are mutually coparallel [dihedral angle = 0.80 (11)°]. The packing (Fig. 2) shows planes of molecules parallel to (201) with an interplanar spacing of 2.99 Å. Within each plane, all the molecules are oriented in the same direction, whereas in neighbouring planes the direction is inverted (Fig. 3). There is no π–π stacking but it is noteworthy that short B···F distances occur between two planes [B1···F5ⁱⁱ = 3.040 (2) and B2···F13ⁱⁱⁱ = 3.1624 (12) Å; symmetry codes: (ii) x, -y + 1, z - 1/2; (iii) x, -y + 2, z - 1/2]. The F atom is located almost directly over the B atom (Fig. 3).

Boroxines with alkyl substituents such as (EtBO)₃ form columns in their crystal structures in which the boroxine rings stack above each other, with each B atom being surrounded by the O atoms of the two neighbouring layers (Fig. 4) (Beckett et al., 1997). Between these layers there are short intermolecular B···O contacts of 3.462 Å. In contrast, boroxines with aryl substituents tend to form, in most cases, a layer structure in the solid state in which the boroxine rings are located between two arene rings of neighbouring layers (Fig. 5) (Brock et al., 1987). Generally, X-ray structure analyses of boroxines provide evidence for the existence of a π-ring system (Haberecht et al., 2005).

In order to compare the molecular and crystal structures of (I) with similar compounds, a Cambridge Structural Database (CSD, Version 5.33 of November 2011, plus one update; Allen, 2002) substructure search for boroxine rings with each B atom connected to a cyclic three-coordinated C atom was undertaken and yielded 17 hits. All rings are essentially planar, with a mean absolute B—O—B—O torsion angle of 3(2)° and a maximum absolute torsion angle of 6.5°. The mean B—O distance over all six B—O bonds in all hits was 1.379 (7) Å. The mean O—B—O angle is 118.4 (9)°, whereas the B—O—B angle has a mean value of 121.5 (9)°.

In (I), the mean absolute B—O—B—O torsion angle is 4(2)°, with a maximum value of -6.5 (2)° for B2—O2—B1—O1. The B—O distances range from 1.364 (2) Å for B1—O2 to 1.3713 (19) Å for B1—O1. In contrast with the structures retrieved from the database, the B—O—B and O—B—O angles in (I) have almost the same values [B1—O1—B1ⁱ = 119.82 (18), B1—O2—B2 = 120.13 (14), O2—B1—O1 = 119.81 (14) and O2—B2—O2ⁱ = 119.8 (2)°; symmetry code: (i) -x, y, -z + 1/2].

Four compounds from the database search are very similar to (I) and merit further investigation. It is remarkable that neither triphenylboroxine [FIPDOX (Boese et al., 1987), FIPDOX01 (Brock et al., 1987) and FIPDOX02 (Bolte, 2004)], 2,4,6-tris(4-bromophenyl)boroxine [LUKKAD (Avent et al., 2002), LUKKAD01 (Jones & Zerbe, 2004) and LUKKAD02 (Bhuvanesh et al., 2005)], tris(p-tolyl)boroxine [NIBGOU (Beckett et al., 1997) and NIBGOU01 (Haberecht et al., 2005)] nor 1,3,5-trimesitylboroxine [SOKLAF (Neumüller & Gahlmann, 1991), SOKLAF01 (Anulewicz-Ostrowska et al., 2000) and SOKLAF02 (Franz et al., 2009)] is isomorphous with (I).

1,3,5-Trimesitylboroxine (SOKLAF) has a completely different packing pattern from (I), which is most probably due to the fact that the mesityl residues are significantly twisted out of the plane of the boroxine ring (35.8 and 40.6°). As a result, this structure will not be discussed in detail.

Although triphenylboroxine (FIPDOX) features a rather planar molecule (r.m.s. deviation for all non-H atoms = 0.178 Å), the crystal packing shows neither planes of coparallel molecules nor any π-stacking. There are only some weak C—H···π contacts in the range 2.93–3.44 Å. The planar boroxine ring (r.m.s. deviation = 0.035 Å) forms dihedral angles of 6.5, 11.9 and 11.6° with the attached phenyl rings.

Tris(p-tolyl)boroxine (NIBGOU) crystallizes, like (I), in the monoclinic space group C2/c with rather different cell parameters [a = 22.591 (2), b = 13.269 (4), c = 6.839 (1) Å, β = 106.82 (2) and V = 1962.3 ų]. As in (I), molecules of NIBGOU are located on a crystallographic twofold rotation axis. The planar boroxine ring (r.m.s. deviation for all non-H atoms = 0.001 Å) forms dihedral angles of 9.3 and 1.9° with the attached phenyl rings; the r.m.s. deviation for all non-H atoms is 0.062 Å. Nevertheless, the packing of the molecules is, on the one hand, similar to that in (I), i.e. the molecules form layers parallel to (201) with an interplanar spacing of 3.25 Å (Fig. 6). The difference in the packing pattern, on the other hand, is that in NIBGOU the boroxine rings are stacked above a benzene ring (Fig. 5). This kind of stacking of rings is not observed in (I), where B···F contacts are found.

NIBGOU01 is a polymorph of NIBGOU. It crystallizes in the orthorhombic space group Pmn2₁ with the molecules located on a crystallographic mirror plane. The boroxine ring is again planar (r.m.s. deviation = 0.019 Å) and forms dihedral angles of 5.7 and 4.2° with the attached benzene rings. Again, the molecules form planes with boroxine rings stacked above benzene rings (Fig. 7), but there are different layers of molecules parallel to (021) and (021). The dihedral angle between the layers is 86.1° and the interplanar spacing is 3.33 Å.

Molecules of 2,4,6-tris(4-bromophenyl)boroxine (LUKKAD) show crystallographic mirror symmetry. The boroxine ring is planar (r.m.s. deviation = 0.016 Å) and makes dihedral angles of 2.9 and 5.4° with the benzene rings. The packing of the molecules resembles a herringbone pattern, with molecules in planes parallel to (401) and (401) (Fig. 8). The dihedral angle between these planes is 88.1° and the interplanar spacing is 3.37 Å. In this case, stacking of boroxine with benzene rings is observed (Fig. 9). The centroid-to-centroid distance is 3.51 Å.

In conclusion, it can be said that aryl-substituted boroxine rings tend to adopt a planar molecular structure. The aryl rings are only twisted out of the boroxine plane if bulky substituents in the ortho position of the aryl substituents avoid coplanarity of the aryl and boroxine rings. The phenyl-, p-bromophenyl-, tolyl- and pentafluorophenyl-substituted boroxines are located on a crystallographic symmetry element, either on a mirror plane or on a twofold rotation axis. Whereas the crystal packing of triphenylboroxine does not reveal any stacking, the molecules of p-bromophenyl-, tolyl- and pentafluorophenylboroxine show a layer structure. However, the kind of stacking is different depending on the substitution pattern of the boroxine ring. In p-bromophenyl- and tolylboroxine, the boroxine rings are stacked above the benzene rings, whereas in pentafluorophenylboroxine no stacks of rings occur but short B···F interactions are found. This is the reason for the different packing pattern of (I) compared with the other boroxines discussed. On the other hand, the alkylsubstituted compound, triethylboroxine, shows perfect boroxine–boroxine stacks.

Related literature

For related literature, see: Allen (2002); Anulewicz-Ostrowska, Luliński, Serwatowski & Suwińska (2000); Avent et al. (2002); Beckett et al. (1997); Bhuvanesh et al. (2005); Boese et al. (1987); Bolte (2004); Bolte & Lerner (2011); Brock et al. (1987); Franz et al. (2009); Haberecht et al. (2005); Jones & Zerbe (2004); Lerner (2005); Meyer-Wegner, Nadj, Bolte, Auner, Wagner, Holthausen & Lerner (2011); Meyer-Wegner, Scholz, Sänger, Schödel, Bolte, Wagner & Lerner (2009); Neumüller & Gahlmann (1991).

S2. Experimental

Tris(pentafluorophenyl)borane monohydrate (0.32 g, 0.60 mmol) and hexachlorodisilane (0.1 ml, 0.57 mmol) were dissolved in C₆D₆ (0.5 ml). The reaction mixture was heated to 453 K for 24 h in a sealed NMR tube. After the reaction mixture had been cooled from 453 K to room temperature, single crystals of the title compound, (I), were obtained (yield 20%).

S3. Refinement

The very strong 402 reflection is unfortunately missing from the data set because it was not measured.

Computing details

Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA (Stoe & Cie, 2001); data reduction: X-AREA (Stoe & Cie, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures

	Fig. 1. A perspective view of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. [Symmetry code: (A) -x, y, -z + 1/2.]
	Fig. 2. A packing diagram for (I), viewed in the ac plane.
	Fig. 3. A partial packing diagram for (I), showing two coparallel planes. The molecules in one plane are drawn with full bonds and those in the second plane with open bonds. The view direction is onto the (201) plane. Cell boundaries have been omitted for clarity.
	Fig. 4. A partial packing diagram for triethylboroxine, viewed perpendicular to the boroxine ring. H atoms have been omitted for clarity. [Symmetry codes: (A) -x + y + 2, -x + 1, z; (B) -y + 1, x - y - 1, z; (C) -x + 2, -y, -z; (D) x - y, x - 1, -z; (E) y + 1, -x + y + 1, -z.]
	Fig. 5. A partial packing diagram for tris(p-tolyl)boroxine, viewed perpendicular to the boroxine ring. H atoms have been omitted for clarity. [Symmetry codes: (A) -x, y, z; (B) x, y, z + 1; (C) -x, y, z + 1.]
	Fig. 6. A packing diagram for the monoclinic form of tris(p-tolyl)boroxine (NIBGOU; Beckett et al., 1997), viewed in the ac plane. H atoms have been omitted for clarity.
	Fig. 7. A packing diagram for the orthorhombic form of tris(p-tolyl)boroxine (NIBGOU01; Haberecht et al., 2005), viewed in the (021) plane. H atoms have been omitted for clarity.
	Fig. 8. A packing diagram for tris(p-bromo)boroxine (LUKKAD; Avent et al., 2002), viewed in the ac plane. H atoms have been omitted for clarity.
	Fig. 9. A partial packing diagram for tris(p-bromo)boroxine (LUKKAD; Avent et al., 2002). H atoms have been omitted for clarity. Centroid-to-centroid distances are drawn as dashed lines.

2,4,6-(pentafluorophenyl)-1,3,5,2,4,6-trioxatriborinane

Crystal data

C18B3F15O3	F(000) = 1128
Mr = 581.61	Dx = 2.152 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 7640 reflections
a = 16.825 (2) Å	θ = 3.3–25.9°
b = 13.1810 (13) Å	µ = 0.24 mm^−1
c = 8.1049 (12) Å	T = 173 K
β = 92.846 (12)°	Block, colourless
V = 1795.2 (4) Å^3	0.28 × 0.28 × 0.26 mm
Z = 4

Data collection

Stoe IPDS II two-circle diffractometer	1680 independent reflections
Radiation source: Genix 3D IµS microfocus X-ray source	1358 reflections with I > 2σ(I)
Genix 3D multilayer optics monochromator	Rint = 0.072
ω scans	θmax = 25.6°, θmin = 3.9°
Absorption correction: multi-scan (X-AREA; Stoe & Cie, 2001)	h = −20→20
Tmin = 0.935, Tmax = 0.939	k = −14→16
9608 measured reflections	l = −9→9

Refinement

Refinement on F^2	0 restraints
Least-squares matrix: full	Primary atom site location: structure-invariant direct methods
R[F^2 > 2σ(F^2)] = 0.037	Secondary atom site location: difference Fourier map
wR(F^2) = 0.103	w = 1/[σ^2(Fo^2) + (0.0652P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.05	(Δ/σ)max = 0.001
1680 reflections	Δρmax = 0.29 e Å^−3
179 parameters	Δρmin = −0.21 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. 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
O1	0.0000	0.62084 (12)	0.2500	0.0182 (4)
O2	0.04622 (7)	0.77635 (8)	0.36481 (12)	0.0189 (3)
B1	0.04931 (10)	0.67300 (13)	0.3599 (2)	0.0155 (4)
B2	0.0000	0.82835 (19)	0.2500	0.0153 (5)
C1	0.11008 (9)	0.61392 (12)	0.47666 (18)	0.0163 (4)
C2	0.16741 (9)	0.66333 (13)	0.57830 (18)	0.0176 (4)
C3	0.22325 (9)	0.61229 (13)	0.67765 (19)	0.0202 (4)
C4	0.22299 (9)	0.50767 (13)	0.67950 (19)	0.0187 (4)
C5	0.16718 (9)	0.45549 (13)	0.58341 (18)	0.0189 (4)
C6	0.11228 (9)	0.50805 (12)	0.48533 (17)	0.0160 (4)
C11	0.0000	0.94716 (16)	0.2500	0.0152 (5)
C12	0.05463 (9)	1.00388 (13)	0.34613 (17)	0.0165 (4)
C13	0.05548 (9)	1.10877 (13)	0.34735 (19)	0.0192 (4)
C14	0.0000	1.16107 (17)	0.2500	0.0198 (5)
F2	0.17075 (6)	0.76455 (7)	0.58242 (11)	0.0254 (3)
F3	0.27688 (6)	0.66311 (8)	0.77170 (12)	0.0292 (3)
F4	0.27584 (6)	0.45778 (8)	0.77636 (12)	0.0269 (3)
F5	0.16568 (6)	0.35375 (7)	0.58790 (11)	0.0267 (3)
F6	0.05967 (6)	0.45201 (7)	0.39554 (12)	0.0216 (3)
F12	0.10979 (5)	0.95806 (8)	0.44444 (12)	0.0219 (3)
F13	0.10867 (6)	1.15963 (8)	0.44324 (12)	0.0276 (3)
F14	0.0000	1.26192 (10)	0.2500	0.0285 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0193 (8)	0.0148 (8)	0.0197 (7)	0.000	−0.0065 (6)	0.000
O2	0.0216 (6)	0.0145 (5)	0.0197 (5)	0.0012 (4)	−0.0069 (4)	0.0005 (4)
B1	0.0161 (9)	0.0141 (8)	0.0163 (8)	0.0001 (6)	0.0006 (7)	−0.0002 (6)
B2	0.0154 (12)	0.0163 (12)	0.0141 (11)	0.000	0.0011 (9)	0.000
C1	0.0154 (8)	0.0169 (8)	0.0164 (7)	−0.0006 (6)	0.0003 (6)	−0.0004 (6)
C2	0.0193 (9)	0.0142 (8)	0.0190 (8)	−0.0004 (6)	−0.0013 (6)	0.0004 (5)
C3	0.0180 (9)	0.0244 (9)	0.0178 (8)	−0.0017 (6)	−0.0032 (6)	−0.0001 (6)
C4	0.0167 (8)	0.0223 (8)	0.0170 (7)	0.0044 (6)	−0.0016 (6)	0.0052 (6)
C5	0.0201 (9)	0.0169 (8)	0.0197 (9)	0.0014 (6)	0.0018 (7)	0.0029 (6)
C6	0.0157 (8)	0.0158 (8)	0.0163 (8)	−0.0009 (5)	−0.0003 (6)	−0.0008 (5)
C11	0.0154 (11)	0.0155 (11)	0.0148 (11)	0.000	0.0004 (8)	0.000
C12	0.0178 (9)	0.0171 (8)	0.0143 (7)	0.0009 (6)	−0.0014 (6)	0.0004 (5)
C13	0.0206 (9)	0.0175 (8)	0.0194 (8)	−0.0041 (6)	−0.0004 (6)	−0.0029 (6)
C14	0.0249 (13)	0.0127 (10)	0.0221 (11)	0.000	0.0041 (9)	0.000
F2	0.0291 (6)	0.0142 (5)	0.0316 (6)	−0.0026 (4)	−0.0112 (4)	−0.0017 (4)
F3	0.0260 (6)	0.0306 (6)	0.0293 (5)	−0.0052 (4)	−0.0151 (4)	−0.0027 (4)
F4	0.0219 (6)	0.0323 (6)	0.0258 (6)	0.0071 (4)	−0.0068 (4)	0.0099 (4)
F5	0.0327 (6)	0.0127 (5)	0.0343 (6)	0.0037 (4)	−0.0036 (4)	0.0040 (4)
F6	0.0230 (6)	0.0151 (5)	0.0260 (5)	−0.0033 (4)	−0.0072 (4)	−0.0022 (4)
F12	0.0205 (5)	0.0196 (5)	0.0246 (5)	0.0009 (4)	−0.0093 (4)	0.0016 (4)
F13	0.0296 (6)	0.0206 (5)	0.0316 (5)	−0.0073 (4)	−0.0100 (4)	−0.0062 (4)
F14	0.0390 (9)	0.0107 (6)	0.0355 (8)	0.000	−0.0014 (6)	0.000

Geometric parameters (Å, º)

O1—B1^i	1.3713 (19)	C4—F4	1.3305 (18)
O1—B1	1.3713 (19)	C4—C5	1.374 (2)
O2—B1	1.364 (2)	C5—F5	1.3418 (19)
O2—B2	1.3669 (16)	C5—C6	1.376 (2)
B1—C1	1.566 (2)	C6—F6	1.3396 (18)
B2—O2^i	1.3669 (16)	C11—C12	1.393 (2)
B2—C11	1.566 (3)	C11—C12^i	1.393 (2)
C1—C6	1.398 (2)	C12—F12	1.3370 (18)
C1—C2	1.398 (2)	C12—C13	1.383 (3)
C2—F2	1.3358 (19)	C13—F13	1.3360 (19)
C2—C3	1.381 (2)	C13—C14	1.377 (2)
C3—F3	1.3325 (19)	C14—F14	1.329 (3)
C3—C4	1.379 (3)	C14—C13^i	1.377 (2)
B1^i—O1—B1	119.82 (18)	C5—C4—C3	119.79 (14)
B1—O2—B2	120.13 (14)	F5—C5—C4	119.88 (13)
O2—B1—O1	119.81 (14)	F5—C5—C6	120.39 (14)
O2—B1—C1	120.24 (14)	C4—C5—C6	119.72 (16)
O1—B1—C1	119.93 (15)	F6—C6—C5	116.29 (15)
O2^i—B2—O2	119.8 (2)	F6—C6—C1	120.53 (13)
O2^i—B2—C11	120.10 (10)	C5—C6—C1	123.18 (14)
O2—B2—C11	120.09 (10)	C12—C11—C12^i	115.1 (2)
C6—C1—C2	114.82 (14)	C12—C11—B2	122.47 (10)
C6—C1—B1	122.81 (14)	C12^i—C11—B2	122.46 (10)
C2—C1—B1	122.36 (16)	F12—C12—C13	116.15 (13)
F2—C2—C3	116.45 (14)	F12—C12—C11	120.68 (15)
F2—C2—C1	120.46 (14)	C13—C12—C11	123.17 (14)
C3—C2—C1	123.09 (17)	F13—C13—C14	119.84 (17)
F3—C3—C4	119.93 (14)	F13—C13—C12	120.81 (14)
F3—C3—C2	120.68 (16)	C14—C13—C12	119.34 (15)
C4—C3—C2	119.40 (14)	F14—C14—C13^i	120.04 (11)
F4—C4—C5	120.31 (15)	F14—C14—C13	120.04 (11)
F4—C4—C3	119.89 (14)	C13^i—C14—C13	119.9 (2)
B2—O2—B1—O1	−6.5 (2)	C3—C4—C5—C6	0.4 (2)
B2—O2—B1—C1	172.29 (11)	F5—C5—C6—F6	−1.0 (2)
B1^i—O1—B1—O2	3.25 (10)	C4—C5—C6—F6	−179.83 (13)
B1^i—O1—B1—C1	−175.55 (17)	F5—C5—C6—C1	179.22 (13)
B1—O2—B2—O2^i	3.27 (10)	C4—C5—C6—C1	0.4 (2)
B1—O2—B2—C11	−176.73 (10)	C2—C1—C6—F6	179.07 (13)
O2—B1—C1—C6	175.45 (14)	B1—C1—C6—F6	−2.1 (2)
O1—B1—C1—C6	−5.8 (2)	C2—C1—C6—C5	−1.1 (2)
O2—B1—C1—C2	−5.8 (2)	B1—C1—C6—C5	177.73 (15)
O1—B1—C1—C2	173.04 (13)	O2^i—B2—C11—C12	−169.67 (9)
C6—C1—C2—F2	−179.20 (13)	O2—B2—C11—C12	10.33 (9)
B1—C1—C2—F2	1.9 (2)	O2^i—B2—C11—C12^i	10.33 (9)
C6—C1—C2—C3	1.3 (2)	O2—B2—C11—C12^i	−169.67 (9)
B1—C1—C2—C3	−177.63 (15)	C12^i—C11—C12—F12	179.60 (15)
F2—C2—C3—F3	0.1 (2)	B2—C11—C12—F12	−0.40 (15)
C1—C2—C3—F3	179.68 (14)	C12^i—C11—C12—C13	−0.09 (10)
F2—C2—C3—C4	179.85 (13)	B2—C11—C12—C13	179.91 (10)
C1—C2—C3—C4	−0.6 (2)	F12—C12—C13—F13	−0.4 (2)
F3—C3—C4—F4	0.6 (2)	C11—C12—C13—F13	179.28 (12)
C2—C3—C4—F4	−179.12 (15)	F12—C12—C13—C14	−179.53 (11)
F3—C3—C4—C5	179.45 (15)	C11—C12—C13—C14	0.2 (2)
C2—C3—C4—C5	−0.3 (2)	F13—C13—C14—F14	0.81 (16)
F4—C4—C5—F5	0.4 (2)	C12—C13—C14—F14	179.92 (10)
C3—C4—C5—F5	−178.47 (13)	F13—C13—C14—C13^i	−179.20 (16)
F4—C4—C5—C6	179.22 (13)	C12—C13—C14—C13^i	−0.09 (10)

Symmetry code: (i) −x, y, −z+1/2.