Bis(methyl­tri-o-tolyl­phospho­nium) octa­iodide

In the crystal structure of the title compound, 2C₂₂H₂₄P⁺·I₈^2-, the I₈^2- anion is located on a crystallographic inversion centre and consists of two tri-iodide anions linked by di-iodine at angles of 89.92 (4)° to form a planar `Z'-shaped dianion. The octa­iodides are linked via long-range inter­actions [3.877 (11) Å] into infinite polyiodide ribbons. This is the first example of a structure containing an [(o-tol­yl)₃PMe]⁺ cation, and the C_Me-P-C-C_Me torsion angles of -54.0 (11), -51.3 (11) and -48.2 (11)° indicate that the configuration is exo₃.

S1. Comment

The octaiodide anion is a member of the dianionic polyiodide series I_2n+2^2-, whose first three members would be expected to consist of a di-iodine combined, respectively, with two iodide anions, an iodide and tri-iodide and two tri-iodide anions. The tetra-iodide is the most frequently encountered polyiodide in the I_2n+2^2- series and in all cases the I₄^2- anion is linear. No intermolecular I···I contacts less than 4 Å have been observed in these compounds (Kloo & Svensson, 2003). To date no structure containing an undisordered I₆^2- has been reported. It is therefore somewhat surprising that several I₈^2--containing structures are known. The first I₈^2- ion was determined by Havinga et al. (1954) in Cs₂I₈. Generally an I₈^2- ion consists of two I₃^- ions that interact with an I₂ molecule to form `Z'-shaped [(I<sub>3</sub><sup>-</sup>)<sub>2</sub>.(I<sub>2</sub>)]. This geometry, which includes out-stretched (`S'-shaped) or slightly deformed forms, is the predominating geometry for all structurally characterized octaiodide ions.

In the title structure, {2[(o-tolyl)₃PMe]⁺ + I₈^2-}, the I₈^2- has a `Z' shape (Fig. 1). The bonding distances in the octaiodide indicate that it is made up of two tri-iodide anions and a di-iodine molecule (Table 1). Although the `Z' angle is 81° in the inorganic Cs₂I₈, the `Z' angle of 89.92 (4)° in the current structure is the most acute seen in structures containing organic cations. In the title molecule the I<sub>8</sub><sup>2-</sup> `Z' is completely flat with the two I₃^- units configured trans to one another. In other words, the torsion angle defined by the angle between the two I₃^- ions when projected down the I₂ bond is 180°, as required by the centre of inversion that relates them. This is the configuration seen in all known I₈^2- ions except for the tris(1,10-phenanthroline)iron(II) complex, C₃₆H₂₄FeN₆²⁺, I₈^2- (-82.1°) (Horn et al., 2001) and the dihydrogen(2.2.2)cryptand, C₁₈H₃₈N₂ O₆²⁺, I₈^2- (-99.3°) (Grafe-Kavoosian et al., 1998). It is interesting that the central torsion angle is either 180° or close to 90°.

Each I₈^2- anion in the present structure associates with two adjacent anions via long contacts of 3.977 (1) Å to form infinite polyiodide ribbons along [100] (Fig. 2). Interestingly this is the first example where the long-range interactions between I₈^2- ions involve both the I₃^- and I₂ moieties. In all other cases, where interionic interactions occur between I₈^2- units, only the I₃^- ions are involved. When only one iodine in each I₃^- ion takes part in long-range interactions, a helical (Horn et al., 2001) or branched (Kuhn et al., 2000) chain is produced. When both terminal I₃^- iodine atoms are employed, puckered sheets result (Grafe-Kavoosian et al., 1998; Kuz'mina et al., 2000). Although the number of long-range I···I interactions are the same in the title structure as they are in the puckered sheets, involvement of the central I₂ gives lower conformational freedom, leading to flat ribbons.

The C_Me—P—C—C_Me torsion angle values of C22—P1—C1—C2, -54.0 (11)°, C22—P1—C8—C9, -51.3 (11)°, and C22—P1—C15—C16, -48.2 (11)° confirm that the configuration is exo₃, which is as expected for a tri-o-tolylphosphine moiety with a small apical substituent cf. (o-tolyl)₃P═O, which is also exo₃ and whose corresponding torsion angles fall in the range 33.8 to 52.4° with an average value of 45.9°. See Howell et al. (1992) for a previous example of the exo notation being used in tris(ortho-tolyl) derivatives of P, As and Si. The larger torsion angles in the title cation reflect the slightly larger size of CH₃ relative to O and must be at the upper limit for the exo₃ configuration. The increased size of the apical substituent in (o-tolyl)₃P═S flips the structure to an exo₂ configuration even though, according to Pauling, CH₃ has a larger Van der Waals' radius than S. This is because H atoms of the ortho-CH₃ groups nestle between the H atoms of the apical CH₃, effectively reducing the Van der Waals' radius of the methyl group.

Related literature

For related literature, see: Kuz'mina Palkina Savinkina Kozlova Kuznetsov (2000); Grafe-Kavoosian et al. (1998); Havinga et al. (1954); Horn et al. (2001); Howell et al. (1992); Kloo & Svensson (2003); Kuhn et al. (2000).

S2. Experimental

Equimolar quantities of methyliodide and tri-o-tolylphosphine were reacted in dry dichloromethane at room temperature. The containers were stoppered but further precautions to protect the sample from the atmosphere were deemed unnecessary. Anhydrous dichloromethane (25 ml) was added to a dry Rotaflo tube. To this solution was added (o-CH₃C₆H₄)₃P (1.005 g, 3.30 mmol) which rapidly dissolved. Iodomethane (0.60 ml, 9.91 mol) was added slowly over a period of several minutes. After 5 min a white solid gradually formed and the reaction was left to stir for a further 24 h. The solid was then isolated using standard Schlenk techniques and dried in vacuo for 2 h to yield 1.394 g of a solid (94.6% yield). Analysis calculated for C₂₂H₂₄PI₄: C 59.2, H 5.4, I 28.5%; found: C 59.1, H 5.3, I 28.1%. For recrystallization, the compound was dissolved in CH₂Cl₂. Iodine was added to the solution, [which was] dissolved in dichloromethane in a 2:1 molar ratio. The solution was allowed to stand for 4 d to allow dark-red crystals to form by slow evaporation: 2[(o-tolyl)₃PCH₃]⁺ + 2I^- + 3I₂ → 2[(o-tolyl)₃PCH₃]⁺+ I₈^-2.

S3. Refinement

H atoms were constrained to chemically reasonable positions, with C—H bond lengths set at 0.95 Å for phenyl and at 0.98 Å for methyl groups. U_iso(H) values were set at 1.2 times the U_eq values of the attached C atoms in phenyl rings and at 1.5 times the U_eq value for methyl H atoms. The largest peaks remaining in the difference map have electron densities of 4.7 and 3.6 e Å^-3. They are arranged linearly on either side of I4 at distances of 2.924 and 2.964 Å, forming an I₃^- shape. No credible twin model was found, and no indication of spot splitting could be seen in the X-ray images. It was therefore concluded that the best explanation for the residual electron density was a minor secondary phase that had intergrown with the primary structure.

Computing details

Data collection: COLLECT (Nonius, 1998); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 1999) and publCIF (Westrip, 2010).

Figures

	Fig. 1. View of the methyltri-o-tolylphosphonium cation and the centrosymmetric octaiodide dianion, including the atom-labelling scheme. [Symmetry code: (i) -x + 1, -y, -z + 1.]
	Fig. 2. The octaiodide anions linked into a polyiodide ribbon viewed down the crystallographic b axis.

Bis(methyltri-o-tolylphosphonium) octaiodide

Crystal data

2C22H24P^+·I8^2^−	Z = 1
Mr = 1653.96	F(000) = 766
Triclinic, P1	Dx = 2.131 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 9.6680 (2) Å	Cell parameters from 5850 reflections
b = 12.3567 (3) Å	θ = 1.0–27.5°
c = 12.8186 (4) Å	µ = 4.90 mm^−1
α = 62.364 (1)°	T = 100 K
β = 76.410 (1)°	Prism, colourless
γ = 73.073 (1)°	0.15 × 0.1 × 0.1 mm
V = 1288.83 (6) Å^3

Data collection

Nonius KappaCCD diffractometer	4776 independent reflections
Radiation source: Enraf–Nonius FR590	3762 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0
Detector resolution: 9 pixels mm^-1	θmax = 25.5°, θmin = 3.1°
CCD rotation images, thick slices scans	h = 0→11
Absorption correction: multi-scan (Blessing, 1995)	k = −13→14
Tmin = 0.527, Tmax = 0.640	l = −14→15
4776 measured reflections

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)] = 0.069	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.183	H-atom parameters constrained
S = 1.15	w = 1/[σ^2(Fo^2) + (0.0697P)^2 + 33.6613P] where P = (Fo^2 + 2Fc^2)/3
4776 reflections	(Δ/σ)max = 0.01
247 parameters	Δρmax = 4.65 e Å^−3
0 restraints	Δρmin = −2.84 e Å^−3

Special details

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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.

Highest peak 4.65 at 0.8008 0.0396 0.3150 [1.58 A from I3] Deepest hole -2.84 at 0.8106 0.0962 0.2631 [0.88 A from I3]

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
C1	−0.0514 (13)	0.6483 (10)	0.2440 (10)	0.027 (2)
C2	−0.1762 (12)	0.7405 (11)	0.2010 (10)	0.028 (2)
C3	−0.2969 (14)	0.7014 (12)	0.1980 (11)	0.036 (3)
H3	−0.3818	0.7623	0.169	0.043*
C4	−0.2957 (15)	0.5768 (13)	0.2360 (11)	0.038 (3)
H4	−0.3792	0.5521	0.2344	0.046*
C5	−0.1704 (16)	0.4878 (13)	0.2770 (13)	0.043 (3)
H5	−0.1677	0.4022	0.3008	0.052*
C6	−0.0494 (14)	0.5222 (11)	0.2836 (11)	0.031 (3)
H6	0.0339	0.4603	0.3148	0.038*
C7	−0.1839 (15)	0.8778 (11)	0.1541 (13)	0.040 (3)
H7A	−0.1376	0.9092	0.0719	0.059*
H7B	−0.1331	0.8921	0.2028	0.059*
H7C	−0.286	0.9217	0.1569	0.059*
C8	0.0676 (12)	0.7516 (10)	0.3600 (10)	0.026 (2)
C9	0.1674 (12)	0.8064 (10)	0.3740 (10)	0.028 (2)
C10	0.1244 (14)	0.8526 (11)	0.4603 (11)	0.034 (3)
H10	0.1893	0.8896	0.4721	0.041*
C11	−0.0093 (15)	0.8463 (12)	0.5290 (11)	0.039 (3)
H11	−0.0349	0.8796	0.5862	0.046*
C12	−0.1059 (13)	0.7920 (11)	0.5153 (11)	0.032 (3)
H12	−0.1978	0.7878	0.5623	0.038*
C13	−0.0660 (13)	0.7431 (11)	0.4308 (11)	0.031 (3)
H13	−0.1305	0.7037	0.4216	0.038*
C14	0.3155 (13)	0.8166 (12)	0.3027 (12)	0.034 (3)
H14A	0.3566	0.7425	0.287	0.05*
H14B	0.3801	0.8225	0.3476	0.05*
H14C	0.3058	0.8915	0.2274	0.05*
C15	0.2541 (13)	0.5491 (10)	0.2975 (11)	0.031 (3)
C16	0.3251 (14)	0.4933 (11)	0.2217 (11)	0.033 (3)
C17	0.4397 (14)	0.3890 (11)	0.2652 (12)	0.035 (3)
H17	0.4921	0.3486	0.2158	0.042*
C18	0.4783 (14)	0.3438 (10)	0.3781 (11)	0.032 (3)
H18	0.5568	0.274	0.4043	0.038*
C19	0.4037 (14)	0.3992 (12)	0.4519 (12)	0.040 (3)
H19	0.4285	0.3669	0.5299	0.048*
C20	0.2936 (13)	0.5011 (11)	0.4123 (11)	0.031 (2)
H20	0.2425	0.5403	0.463	0.037*
C21	0.2909 (15)	0.5379 (12)	0.0958 (12)	0.039 (3)
H21A	0.1863	0.5726	0.092	0.058*
H21B	0.3192	0.4672	0.0744	0.058*
H21C	0.3452	0.6025	0.0403	0.058*
C22	0.1675 (14)	0.8032 (11)	0.1074 (11)	0.036 (3)
H22A	0.1892	0.7682	0.0492	0.054*
H22B	0.2551	0.8249	0.1117	0.054*
H22C	0.0897	0.8784	0.0832	0.054*
I1	0.46014 (8)	0.16783 (8)	0.08788 (7)	0.0357 (2)
I2	0.13654 (8)	0.17991 (7)	0.14356 (7)	0.0318 (2)
I3	−0.16302 (9)	0.16748 (8)	0.21429 (7)	0.0362 (2)
I4	0.49111 (8)	0.03495 (7)	0.38206 (8)	0.0345 (2)
P1	0.1093 (3)	0.6890 (3)	0.2512 (3)	0.0257 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.032 (6)	0.025 (6)	0.024 (5)	−0.001 (5)	−0.009 (5)	−0.009 (5)
C2	0.026 (6)	0.030 (6)	0.033 (6)	−0.004 (5)	−0.003 (5)	−0.017 (5)
C3	0.032 (6)	0.043 (7)	0.034 (7)	−0.005 (5)	0.000 (5)	−0.020 (6)
C4	0.041 (7)	0.047 (8)	0.030 (6)	−0.023 (6)	−0.003 (5)	−0.012 (6)
C5	0.049 (8)	0.035 (7)	0.048 (8)	−0.017 (6)	−0.009 (6)	−0.015 (6)
C6	0.036 (7)	0.031 (6)	0.033 (6)	−0.009 (5)	0.000 (5)	−0.020 (5)
C7	0.043 (7)	0.026 (6)	0.050 (8)	0.008 (5)	−0.019 (6)	−0.019 (6)
C8	0.030 (6)	0.016 (5)	0.032 (6)	−0.007 (4)	−0.002 (5)	−0.011 (4)
C9	0.028 (6)	0.020 (5)	0.032 (6)	0.000 (4)	−0.007 (5)	−0.009 (5)
C10	0.041 (7)	0.027 (6)	0.033 (6)	0.001 (5)	−0.015 (5)	−0.012 (5)
C11	0.044 (7)	0.036 (7)	0.033 (7)	0.004 (6)	−0.006 (6)	−0.019 (6)
C12	0.031 (6)	0.034 (6)	0.028 (6)	0.001 (5)	−0.006 (5)	−0.015 (5)
C13	0.034 (6)	0.025 (6)	0.034 (6)	−0.002 (5)	−0.012 (5)	−0.010 (5)
C14	0.032 (6)	0.031 (6)	0.042 (7)	−0.012 (5)	0.000 (5)	−0.019 (5)
C15	0.036 (6)	0.021 (5)	0.040 (7)	−0.004 (5)	−0.009 (5)	−0.016 (5)
C16	0.036 (7)	0.027 (6)	0.038 (7)	−0.008 (5)	−0.012 (5)	−0.012 (5)
C17	0.037 (7)	0.031 (6)	0.040 (7)	0.000 (5)	−0.004 (5)	−0.022 (6)
C18	0.038 (7)	0.012 (5)	0.043 (7)	0.000 (4)	−0.012 (5)	−0.010 (5)
C19	0.034 (7)	0.037 (7)	0.043 (7)	−0.006 (5)	−0.020 (6)	−0.006 (6)
C20	0.033 (6)	0.026 (6)	0.035 (6)	−0.003 (5)	−0.004 (5)	−0.016 (5)
C21	0.041 (7)	0.038 (7)	0.040 (7)	−0.001 (6)	−0.008 (6)	−0.023 (6)
C22	0.041 (7)	0.023 (6)	0.038 (7)	−0.001 (5)	−0.006 (6)	−0.010 (5)
I1	0.0289 (4)	0.0428 (5)	0.0347 (4)	−0.0060 (3)	−0.0035 (3)	−0.0169 (4)
I2	0.0331 (4)	0.0318 (4)	0.0314 (4)	−0.0057 (3)	−0.0033 (3)	−0.0152 (3)
I3	0.0306 (4)	0.0453 (5)	0.0397 (5)	−0.0087 (3)	−0.0041 (3)	−0.0234 (4)
I4	0.0307 (4)	0.0330 (4)	0.0461 (5)	−0.0078 (3)	−0.0020 (3)	−0.0225 (4)
P1	0.0276 (15)	0.0216 (13)	0.0294 (15)	−0.0054 (11)	−0.0035 (12)	−0.0118 (12)

Geometric parameters (Å, º)

C1—C6	1.394 (16)	C13—H13	0.95
C1—C2	1.410 (16)	C14—H14A	0.98
C1—P1	1.800 (12)	C14—H14B	0.98
C2—C3	1.402 (17)	C14—H14C	0.98
C2—C7	1.499 (17)	C15—C16	1.387 (18)
C3—C4	1.379 (19)	C15—C20	1.409 (17)
C3—H3	0.95	C15—P1	1.825 (12)
C4—C5	1.39 (2)	C16—C17	1.411 (17)
C4—H4	0.95	C16—C21	1.529 (17)
C5—C6	1.387 (18)	C17—C18	1.387 (18)
C5—H5	0.95	C17—H17	0.95
C6—H6	0.95	C18—C19	1.371 (19)
C7—H7A	0.98	C18—H18	0.95
C7—H7B	0.98	C19—C20	1.363 (17)
C7—H7C	0.98	C19—H19	0.95
C8—C13	1.394 (17)	C20—H20	0.95
C8—C9	1.413 (16)	C21—H21A	0.98
C8—P1	1.806 (11)	C21—H21B	0.98
C9—C10	1.397 (17)	C21—H21C	0.98
C9—C14	1.511 (17)	C22—P1	1.808 (13)
C10—C11	1.383 (19)	C22—H22A	0.98
C10—H10	0.95	C22—H22B	0.98
C11—C12	1.380 (18)	C22—H22C	0.98
C11—H11	0.95	I1—I2	3.0162 (11)
C12—C13	1.401 (17)	I2—I3	2.8511 (11)
C12—H12	0.95	I4—I4^i	2.7663 (17)
C6—C1—C2	120.7 (11)	C9—C14—H14B	109.5
C6—C1—P1	117.9 (9)	H14A—C14—H14B	109.5
C2—C1—P1	121.4 (9)	C9—C14—H14C	109.5
C3—C2—C1	118.0 (11)	H14A—C14—H14C	109.5
C3—C2—C7	118.6 (11)	H14B—C14—H14C	109.5
C1—C2—C7	123.3 (11)	C16—C15—C20	121.0 (11)
C4—C3—C2	121.7 (12)	C16—C15—P1	121.3 (9)
C4—C3—H3	119.1	C20—C15—P1	117.6 (9)
C2—C3—H3	119.1	C15—C16—C17	116.3 (11)
C3—C4—C5	119.0 (12)	C15—C16—C21	125.1 (11)
C3—C4—H4	120.5	C17—C16—C21	118.6 (11)
C5—C4—H4	120.5	C18—C17—C16	122.0 (11)
C6—C5—C4	121.1 (12)	C18—C17—H17	119
C6—C5—H5	119.4	C16—C17—H17	119
C4—C5—H5	119.4	C19—C18—C17	120.4 (11)
C5—C6—C1	119.3 (12)	C19—C18—H18	119.8
C5—C6—H6	120.3	C17—C18—H18	119.8
C1—C6—H6	120.3	C20—C19—C18	119.3 (12)
C2—C7—H7A	109.5	C20—C19—H19	120.4
C2—C7—H7B	109.5	C18—C19—H19	120.4
H7A—C7—H7B	109.5	C19—C20—C15	121.1 (12)
C2—C7—H7C	109.5	C19—C20—H20	119.5
H7A—C7—H7C	109.5	C15—C20—H20	119.5
H7B—C7—H7C	109.5	C16—C21—H21A	109.5
C13—C8—C9	120.9 (10)	C16—C21—H21B	109.5
C13—C8—P1	117.8 (8)	H21A—C21—H21B	109.5
C9—C8—P1	121.3 (9)	C16—C21—H21C	109.5
C10—C9—C8	116.8 (11)	H21A—C21—H21C	109.5
C10—C9—C14	119.1 (11)	H21B—C21—H21C	109.5
C8—C9—C14	124.1 (10)	P1—C22—H22A	109.5
C11—C10—C9	122.4 (12)	P1—C22—H22B	109.5
C11—C10—H10	118.8	H22A—C22—H22B	109.5
C9—C10—H10	118.8	P1—C22—H22C	109.5
C12—C11—C10	120.5 (12)	H22A—C22—H22C	109.5
C12—C11—H11	119.7	H22B—C22—H22C	109.5
C10—C11—H11	119.7	I3—I2—I1	174.42 (4)
C11—C12—C13	118.9 (12)	C1—P1—C22	109.8 (6)
C11—C12—H12	120.6	C1—P1—C8	108.7 (5)
C13—C12—H12	120.6	C22—P1—C8	110.4 (5)
C8—C13—C12	120.5 (11)	C1—P1—C15	109.4 (5)
C8—C13—H13	119.7	C22—P1—C15	109.8 (6)
C12—C13—H13	119.7	C8—P1—C15	108.7 (5)
C9—C14—H14A	109.5
C6—C1—C2—C3	−0.7 (17)	C15—C16—C17—C18	0.8 (18)
P1—C1—C2—C3	179.9 (9)	C21—C16—C17—C18	179.3 (12)
C6—C1—C2—C7	−178.3 (11)	C16—C17—C18—C19	0.8 (19)
P1—C1—C2—C7	2.4 (17)	C17—C18—C19—C20	−1.6 (19)
C1—C2—C3—C4	0.2 (18)	C18—C19—C20—C15	0.8 (19)
C7—C2—C3—C4	177.9 (12)	C16—C15—C20—C19	0.7 (18)
C2—C3—C4—C5	−0.9 (19)	P1—C15—C20—C19	−177.9 (10)
C3—C4—C5—C6	2 (2)	C6—C1—P1—C22	126.6 (9)
C4—C5—C6—C1	−3 (2)	C2—C1—P1—C22	−54.0 (11)
C2—C1—C6—C5	1.9 (18)	C6—C1—P1—C8	−112.6 (10)
P1—C1—C6—C5	−178.7 (10)	C2—C1—P1—C8	66.8 (11)
C13—C8—C9—C10	−0.9 (16)	C6—C1—P1—C15	6.0 (11)
P1—C8—C9—C10	179.7 (8)	C2—C1—P1—C15	−174.6 (10)
C13—C8—C9—C14	178.6 (11)	C13—C8—P1—C1	8.8 (10)
P1—C8—C9—C14	−0.7 (16)	C9—C8—P1—C1	−171.8 (9)
C8—C9—C10—C11	−0.3 (17)	C13—C8—P1—C22	129.3 (9)
C14—C9—C10—C11	−179.9 (11)	C9—C8—P1—C22	−51.3 (11)
C9—C10—C11—C12	0.7 (19)	C13—C8—P1—C15	−110.2 (9)
C10—C11—C12—C13	0.2 (18)	C9—C8—P1—C15	69.2 (10)
C9—C8—C13—C12	1.8 (17)	C16—C15—P1—C1	72.4 (11)
P1—C8—C13—C12	−178.8 (9)	C20—C15—P1—C1	−108.9 (10)
C11—C12—C13—C8	−1.4 (17)	C16—C15—P1—C22	−48.2 (11)
C20—C15—C16—C17	−1.5 (17)	C20—C15—P1—C22	130.5 (10)
P1—C15—C16—C17	177.1 (9)	C16—C15—P1—C8	−169.1 (10)
C20—C15—C16—C21	−180.0 (12)	C20—C15—P1—C8	9.6 (11)
P1—C15—C16—C21	−1.3 (17)

Symmetry code: (i) −x+1, −y, −z+1.