1,4-Bis[(2,6-dimethoxy­phen­yl)ethyn­yl]benzene

Ono, K.; Tsukamoto, K.; Tomura, M.; Saito, K.

doi:10.1107/S1600536808013664

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 64| Part 6| June 2008| Page o1069

doi:10.1107/S1600536808013664

Open

access

1,4-Bis[(2,6-dimethoxyphenyl)ethynyl]benzene

Katsuhiko Ono,^a ^* Kenichi Tsukamoto,^a Masaaki Tomura ^b and Katsuhiro Saito ^a

^aDepartment of Materials Science and Engineering, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan, and ^bInstitute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan
^*Correspondence e-mail: ono.katsuhiko@nitech.ac.jp

(Received 2 May 2008; accepted 8 May 2008; online 14 May 2008)

The title compound, C₂₆H₂₂O₄, is a derivative of 1,4-bis(phenylethynyl)benzene substituted by four methoxy groups at the terminal benzene rings. The asymmetric unit consists of two half-molecules; one centrosymmetric molecule is planar but the other is non-planar, with dihedral angles of 67.7 (1)° between the central benzene ring and the terminal benzene rings. In the crystal structure, molecules form a zigzag molecular network due to π–π [the interplanar and centroid–centroid distances between the benzene rings are 3.50 (1) and 3.57 (1) Å, respectively] and C—H⋯π interactions (2.75 Å). Introduction of the four methoxy groups results in the supramolecular architecture.

Related literature

The synthetic research of ethynylated aromatic compounds has attracted considerable attention because of interest in their molecular structures (Bunz et al., 1999 ; Kawase et al., 2003 ), optical properties (Beeby et al., 2002 ; Bunz, 2000 ) and molecular electronics (Tour, 2000 ). 1,4-Bis(phenylethynyl)benzene is used as a building block in applications such as liquid-crystalline materials (Dai et al., 1999 ) and electron-conducting molecular wires (Moore et al., 2006 ). For related molecular structures, including a 1,4-bis(phenylethynyl)benzene system, see: Watt et al. (2004 ); Li et al. (1998 ); Filatov & Petrukhina (2005 ).

Experimental

Crystal data

C₂₆H₂₂O₄
M_r = 398.44
Monoclinic, P 2₁ /c
a = 12.391 (4) Å
b = 10.313 (3) Å
c = 16.611 (5) Å
β = 95.323 (4)°
V = 2113.5 (11) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 173 (1) K
0.47 × 0.35 × 0.10 mm

Data collection

Rigaku/MSC Mercury CCD diffractometer
Absorption correction: none
16248 measured reflections
4775 independent reflections
4206 reflections with I > 2σ(I)
R_int = 0.028

Refinement

R[F² > 2σ(F²)] = 0.055
wR(F²) = 0.120
S = 1.12
4775 reflections
271 parameters
H-atom parameters constrained
Δρ_max = 0.20 e Å⁻³
Δρ_min = −0.16 e Å⁻³

Data collection: CrystalClear (Rigaku/MSC, 2001 ); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SIR2004 (Burla et al., 2005 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: PLATON (Spek, 2003 ) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808013664/xu2425sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808013664/xu2425Isup2.hkl

checkCIF report

Comment top

The synthetic research of ethynylated aromatic compounds has attracted considerable attention because of interests in their molecular structures (Bunz et al., 1999; Kawase et al., 2003), optical properties (Beeby et al., 2002; Bunz, 2000) and molecular electronics (Tour, 2000). Among these ethynylated aromatic compounds, 1,4-bis(phenylethynyl)benzene derivatives have been extensively studied. These compounds have stiff, linear molecular structures and are used as building blocks in the applications such as liquid-crystalline materials (Dai et al., 1999) and electron-conducting molecular wires (Moore et al., 2006). According to the X-ray crystallographic analyses of 1,4-bis(phenylethynyl)benzene, the molecules crystallize in two crystal forms with the P1 and Pbcn space groups (Watt et al., 2004; Li et al., 1998). In both crystals, the molecules are linear and planar. In P1, the molecules are aggregated by the face-to-edge interactions based on C—H···π contacts (2.74–2.89 Å). In Pbcn, the molecules form π-dimers with an intermolecular distance of 3.49 Å. The π-dimers are aggregated by the face-to-face interactions based on π···π contacts (3.45 Å) and the face-to-edge interactions based on C—H···π contacts (benzene ring) (2.85–2.88 Å) and C—H···π contacts (C≡C bond) (2.79–2.87 Å). Furthermore, the X-ray crystallographic analysis carried out on 1,4-bis(p-tolylethynyl)benzene in P2₁/c (Filatov & Petrukhina, 2005) again showed the molecule to be linear and planar. The molecules are stacked along the b axis to form a column with intermolecular distances of 3.51 and 3.56 Å. This result indicates that the introduction of two methyl groups to the terminal benzene rings provides the modification of molecular assembly. With regard to this, we investigated the molecular and crystal structure of the title compound, (I), which is a derivative substituted by four methoxy groups at the terminal benzene rings.

Single crystals of (I) were grown by recrystallization from dichloromethane. These produce a structure in P2₁/c that shows two crystallographically independent molecules, each possessing an inversion centre (Fig. 1). One molecule is planar and strained at the C≡C bonds. The other molecule is a linear, nonplanar structure with a dihedral angle of 67.7 (1)° between the central benzene ring and the terminal benzene rings. The C≡C bond lengths are 1.200 (2) Å (C7—C8) and 1.199 (2) Å (C20—C21). These values are analogous to those of 1,4-bis(phenylethynyl)benzene (1.202–1.205 Å). The C≡C—C bond angles are 173.1 (2)° (C1—C7—C8), 174.3 (2)° (C7—C8—C9), 178.6 (2)° (C14—C20—C21) and 178.7 (2)° (C20—C21—C22). The bond angles of C1—C7—C8 and C7—C8—C9 are strained as compared to those of 1,4-bis(phenylethynyl)benzene (176.9°–179.5°). Both the molecules alternately arrange to form a zigzag molecular chain due to the π···π and C—H···π interactions (Fig. 2). The terminal benzene rings overlap each other to form a π-stacking (Fig. 3). The interplanar and centroid-centroid distances between the benzene rings are 3.50 (1) and 3.57 (1) Å, respectively. The C—H···π contact between the H26C atom and the C8 atom is observed (2.75 Å). This contact affords the strained structure at the C≡C bonds between the C7 and C8 atoms. Furthermore, the four methoxy groups lock the benzene dimer to provide the zigzag molecular network (Fig. 4). Thus, the introduction of four methoxy groups to the terminal benzene rings forms a supramolecular architecture of 1,4-bis(phenylethynyl)benzene.

In summary, we studied the molecular and crystal structure of 1,4-bis[(2,6-dimethoxyphenyl)ethynyl]benzene, which is a 1,4-bis(phenylethynyl)benzene derivative substituted by four methoxy groups at the terminal benzene rings. The methoxy groups fixed a π-stacking geometry between the terminal benzene rings resulting in the formation of the zigzag molecular network. The introduction of methoxy groups provided a supramolecular architecture of 1,4-bis(phenylethynyl)benzene.

Related literature top

The synthetic research of ethynylated aromatic compounds has attracted considerable attention because of interest in their molecular structures (Bunz et al., 1999; Kawase et al., 2003), optical properties (Beeby et al., 2002; Bunz, 2000) and molecular electronics (Tour, 2000). 1,4-Bis(phenylethynyl)benzene is used as a building block in the applications such as liquid-crystalline materials (Dai et al., 1999) and electron-conducting molecular wires (Moore et al., 2006). For related molecular structures, including a 1,4-bis(phenylethynyl)benzene system, see: Watt et al. (2004); Li et al. (1998); Filatov & Petrukhina (2005).

Experimental top

The title compound (I) was prepared as follows: Bis(triphenylphosphine)palladium(II) dichloride [Pd(PPh₃)₂Cl₂] (10 mg, 0.014 mmol) was added to a mixture of 1-ethynyl-2,6-dimethoxybenzene (76 mg, 0.47 mmol), 1,4-diiodobenzene (77 mg, 0.23 mmol), and copper(I) iodide (3 mg, 0.014 mmol) in dry DMF (5 ml) and dry triethylamine (5 ml) under nitrogen. The reaction mixture was stirred for 16 h at 80 °C. After removal of the solvent, dichloromethane (30 ml) and aqueous disodium ethylenediaminetetraacetate (Na₂edta) solution (5%, 30 ml) were added. The organic layer was separated and washed with water (30 ml). The organic solution was dried over Na₂SO₄ and concentrated. The residue was separated by column chromatography on silica gel (CH₂Cl₂/hexane = 9: 1) to afford compound (I) (52 mg, 56%) as a yellow powder. Yellow crystals of (I) suitable for X-ray analysis were grown from a dichloromethane solution.

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2001); cell refinement: CrystalClear (Rigaku/MSC, 2001); data reduction: CrystalClear (Rigaku/MSC, 2001); program(s) used to solve structure: SIR2004 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2003) and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. The molecular structures of (I), with atom labels and 50% probability displacement elipsoids for non-H atoms and H atoms are shown as small spheres of arbitrary radii [symmetry codes: (i) 1-x,-y,-z; (ii) 2-x,1-y,1-z].
	Fig. 2. The packing diagram of (I), zigzag molecular chain.
	Fig. 3. The packing diagram of (I), overlap mode.
	Fig. 4. The packing diagram of (I), zigzag network.

1,4-Bis[(2,6-dimethoxyphenyl)ethynyl]benzene top

Crystal data top

C₂₆H₂₂O₄	F(000) = 840
M_r = 398.44	D_x = 1.252 Mg m⁻³
Monoclinic, P2₁/c	Melting point = 528–529 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 12.391 (4) Å	Cell parameters from 5564 reflections
b = 10.313 (3) Å	θ = 3.2–27.5°
c = 16.611 (5) Å	µ = 0.08 mm⁻¹
β = 95.323 (4)°	T = 173 K
V = 2113.5 (11) Å³	Block, yellow
Z = 4	0.47 × 0.35 × 0.10 mm

Data collection top

Rigaku/MSC Mercury CCD diffractometer	4206 reflections with I > 2σ(I)
Radiation source: rotating-anode X-ray tube	R_int = 0.028
Graphite Monochromator monochromator	θ_max = 27.5°, θ_min = 3.2°
Detector resolution: 14.6199 pixels mm^-1	h = −16→11
ϕ and ω scans	k = −13→11
16248 measured reflections	l = −21→21
4775 independent reflections

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) = 0.120	H-atom parameters constrained
S = 1.12	w = 1/[σ²(F_o²) + (0.044P)² + 0.7208P] where P = (F_o² + 2F_c²)/3
4775 reflections	(Δ/σ)_max < 0.001
271 parameters	Δρ_max = 0.20 e Å⁻³
0 restraints	Δρ_min = −0.16 e Å⁻³

Crystal data top

C₂₆H₂₂O₄	V = 2113.5 (11) Å³
M_r = 398.44	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 12.391 (4) Å	µ = 0.08 mm⁻¹
b = 10.313 (3) Å	T = 173 K
c = 16.611 (5) Å	0.47 × 0.35 × 0.10 mm
β = 95.323 (4)°

Data collection top

Rigaku/MSC Mercury CCD diffractometer	4206 reflections with I > 2σ(I)
16248 measured reflections	R_int = 0.028
4775 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.055	0 restraints
wR(F²) = 0.120	H-atom parameters constrained
S = 1.12	Δρ_max = 0.20 e Å⁻³
4775 reflections	Δρ_min = −0.16 e Å⁻³
271 parameters

Special details top

Experimental. IR (KBr, cm^-1): 3002, 2836, 2209, 1582, 1514, 1474, 1429, 1300, 1258, 1113, 1034, 843, 772, 718; ¹H NMR (CDCl₃, δ p.p.m.): 3.92 (s, 12H), 6.56 (d, J = 8.4 Hz, 4H), 7.25 (t, J = 8.4 Hz, 2H), 7.54 (s, 4H); ¹³C NMR (CDCl₃, δ p.p.m.): 56.1, 83.5, 97.8, 101.5, 103.5, 123.4, 130.0, 131.5, 161.5; MS (EI): m/z 399 (M⁺ + 1), 161.

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 (Å²) top

	x	y	z	U_iso*/U_eq
C1	0.78035 (10)	−0.11242 (15)	0.26308 (8)	0.0283 (3)
C2	0.78339 (11)	−0.21811 (16)	0.31655 (9)	0.0316 (3)
C3	0.86038 (12)	−0.22279 (19)	0.38320 (10)	0.0417 (4)
H3	0.8632	−0.2949	0.4189	0.050*
C4	0.93251 (13)	−0.1214 (2)	0.39674 (10)	0.0476 (5)
H4	0.9849	−0.1250	0.4422	0.057*
C5	0.93074 (12)	−0.0146 (2)	0.34601 (10)	0.0437 (4)
H5	0.9809	0.0542	0.3567	0.052*
C6	0.85420 (11)	−0.00986 (16)	0.27909 (9)	0.0332 (3)
C7	0.70162 (11)	−0.10222 (14)	0.19462 (8)	0.0269 (3)
C8	0.63967 (11)	−0.08077 (13)	0.13629 (8)	0.0270 (3)
C9	0.56837 (10)	−0.04176 (13)	0.06729 (8)	0.0238 (3)
C10	0.47959 (11)	−0.11676 (14)	0.03736 (8)	0.0274 (3)
H10	0.4653	−0.1967	0.0628	0.033*
C11	0.58769 (11)	0.07592 (14)	0.02880 (8)	0.0269 (3)
H11	0.6476	0.1281	0.0484	0.032*
C12	0.70206 (18)	−0.4179 (2)	0.35277 (12)	0.0591 (5)
H12A	0.6438	−0.4770	0.3325	0.089*
H12B	0.6878	−0.3857	0.4063	0.089*
H12C	0.7714	−0.4643	0.3568	0.089*
C13	0.90402 (17)	0.2050 (2)	0.24194 (13)	0.0617 (6)
H13A	0.8873	0.2678	0.1983	0.093*
H13B	0.9815	0.1843	0.2460	0.093*
H13C	0.8854	0.2423	0.2931	0.093*
C14	0.70955 (10)	0.10378 (14)	0.44408 (9)	0.0280 (3)
C15	0.70353 (11)	0.00310 (15)	0.50009 (10)	0.0333 (3)
C16	0.62828 (13)	−0.09645 (16)	0.48519 (11)	0.0414 (4)
H16	0.6247	−0.1658	0.5225	0.050*
C17	0.55901 (13)	−0.09237 (17)	0.41523 (12)	0.0451 (4)
H17	0.5071	−0.1597	0.4054	0.054*
C18	0.56229 (12)	0.00605 (17)	0.35890 (10)	0.0401 (4)
H18	0.5134	0.0065	0.3114	0.048*
C19	0.63847 (11)	0.10420 (14)	0.37318 (9)	0.0302 (3)
C20	0.78731 (11)	0.20559 (14)	0.45872 (9)	0.0281 (3)
C21	0.85122 (11)	0.29250 (14)	0.46985 (9)	0.0287 (3)
C22	0.92644 (10)	0.39768 (13)	0.48466 (8)	0.0251 (3)
C23	0.91450 (11)	0.48457 (15)	0.54763 (9)	0.0311 (3)
H23	0.8561	0.4744	0.5803	0.037*
C24	1.01269 (11)	0.41447 (15)	0.43720 (9)	0.0320 (3)
H24	1.0215	0.3561	0.3941	0.038*
C25	0.76768 (17)	−0.0831 (2)	0.62854 (14)	0.0679 (7)
H25A	0.8233	−0.0663	0.6732	0.102*
H25B	0.7787	−0.1696	0.6063	0.102*
H25C	0.6958	−0.0787	0.6485	0.102*
C26	0.58057 (15)	0.21684 (19)	0.25079 (11)	0.0494 (5)
H26A	0.5990	0.2945	0.2209	0.074*
H26B	0.5055	0.2231	0.2644	0.074*
H26C	0.5886	0.1399	0.2173	0.074*
O1	0.70668 (9)	−0.31087 (11)	0.29821 (6)	0.0383 (3)
O2	0.84253 (9)	0.08962 (12)	0.22507 (7)	0.0428 (3)
O3	0.77520 (9)	0.01165 (12)	0.56704 (7)	0.0462 (3)
O4	0.65148 (8)	0.20675 (11)	0.32338 (6)	0.0374 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0245 (6)	0.0386 (8)	0.0220 (7)	0.0056 (6)	0.0025 (5)	−0.0012 (6)
C2	0.0286 (7)	0.0411 (9)	0.0249 (7)	0.0099 (6)	0.0010 (5)	0.0001 (6)
C3	0.0373 (8)	0.0587 (11)	0.0279 (8)	0.0169 (8)	−0.0038 (6)	0.0035 (7)
C4	0.0310 (8)	0.0764 (14)	0.0334 (9)	0.0144 (8)	−0.0082 (6)	−0.0078 (9)
C5	0.0270 (7)	0.0650 (12)	0.0391 (9)	−0.0019 (7)	0.0031 (6)	−0.0161 (9)
C6	0.0294 (7)	0.0447 (9)	0.0263 (7)	0.0011 (6)	0.0077 (6)	−0.0052 (7)
C7	0.0307 (7)	0.0261 (7)	0.0240 (7)	0.0023 (5)	0.0028 (5)	0.0014 (5)
C8	0.0315 (7)	0.0251 (7)	0.0244 (7)	0.0023 (5)	0.0021 (5)	0.0016 (6)
C9	0.0260 (6)	0.0248 (7)	0.0206 (6)	0.0037 (5)	0.0023 (5)	−0.0001 (5)
C10	0.0320 (7)	0.0230 (7)	0.0272 (7)	−0.0013 (5)	0.0023 (5)	0.0050 (5)
C11	0.0267 (6)	0.0255 (7)	0.0278 (7)	−0.0030 (5)	−0.0006 (5)	0.0005 (6)
C12	0.0762 (13)	0.0491 (12)	0.0504 (12)	−0.0019 (10)	−0.0032 (10)	0.0238 (9)
C13	0.0676 (12)	0.0600 (13)	0.0596 (13)	−0.0301 (10)	0.0166 (10)	−0.0093 (10)
C14	0.0229 (6)	0.0256 (7)	0.0358 (8)	−0.0026 (5)	0.0049 (5)	−0.0056 (6)
C15	0.0274 (6)	0.0305 (8)	0.0426 (9)	−0.0034 (6)	0.0054 (6)	−0.0011 (7)
C16	0.0392 (8)	0.0315 (8)	0.0552 (11)	−0.0087 (7)	0.0129 (7)	−0.0013 (8)
C17	0.0361 (8)	0.0408 (10)	0.0597 (11)	−0.0162 (7)	0.0118 (8)	−0.0179 (9)
C18	0.0286 (7)	0.0485 (10)	0.0432 (9)	−0.0069 (7)	0.0033 (6)	−0.0195 (8)
C19	0.0254 (6)	0.0314 (8)	0.0343 (8)	0.0004 (5)	0.0056 (6)	−0.0098 (6)
C20	0.0256 (6)	0.0285 (7)	0.0300 (7)	0.0002 (5)	0.0012 (5)	−0.0003 (6)
C21	0.0274 (6)	0.0284 (7)	0.0295 (7)	−0.0016 (5)	−0.0018 (5)	0.0024 (6)
C22	0.0245 (6)	0.0252 (7)	0.0244 (7)	−0.0023 (5)	−0.0042 (5)	0.0049 (5)
C23	0.0289 (7)	0.0376 (8)	0.0271 (7)	−0.0072 (6)	0.0044 (5)	−0.0015 (6)
C24	0.0325 (7)	0.0346 (8)	0.0289 (7)	−0.0055 (6)	0.0031 (6)	−0.0072 (6)
C25	0.0531 (11)	0.0773 (16)	0.0714 (14)	−0.0161 (10)	−0.0051 (10)	0.0420 (13)
C26	0.0521 (10)	0.0511 (11)	0.0417 (10)	0.0142 (8)	−0.0138 (8)	−0.0071 (8)
O1	0.0445 (6)	0.0364 (6)	0.0326 (6)	0.0021 (5)	−0.0033 (5)	0.0101 (5)
O2	0.0515 (7)	0.0427 (7)	0.0349 (6)	−0.0140 (5)	0.0081 (5)	−0.0049 (5)
O3	0.0429 (6)	0.0470 (7)	0.0468 (7)	−0.0138 (5)	−0.0057 (5)	0.0164 (6)
O4	0.0366 (5)	0.0418 (7)	0.0326 (6)	0.0005 (5)	−0.0035 (4)	−0.0025 (5)

Geometric parameters (Å, º) top

C1—C2	1.404 (2)	C14—C15	1.401 (2)
C1—C6	1.408 (2)	C14—C19	1.404 (2)
C1—C7	1.4318 (19)	C14—C20	1.4306 (19)
C2—O1	1.3630 (19)	C15—O3	1.3601 (19)
C2—C3	1.394 (2)	C15—C16	1.394 (2)
C3—C4	1.380 (3)	C16—C17	1.380 (3)
C3—H3	0.9500	C16—H16	0.9500
C4—C5	1.386 (3)	C17—C18	1.384 (3)
C4—H4	0.9500	C17—H17	0.9500
C5—C6	1.394 (2)	C18—C19	1.389 (2)
C5—H5	0.9500	C18—H18	0.9500
C6—O2	1.362 (2)	C19—O4	1.3614 (19)
C7—C8	1.1996 (19)	C20—C21	1.199 (2)
C8—C9	1.4382 (18)	C21—C22	1.4364 (19)
C9—C10	1.3979 (19)	C22—C23	1.396 (2)
C9—C11	1.4026 (19)	C22—C24	1.3964 (19)
C10—C11ⁱ	1.3821 (19)	C23—C24ⁱⁱ	1.385 (2)
C10—H10	0.9500	C23—H23	0.9500
C11—C10ⁱ	1.3821 (19)	C24—C23ⁱⁱ	1.385 (2)
C11—H11	0.9500	C24—H24	0.9500
C12—O1	1.433 (2)	C25—O3	1.423 (2)
C12—H12A	0.9800	C25—H25A	0.9800
C12—H12B	0.9800	C25—H25B	0.9800
C12—H12C	0.9800	C25—H25C	0.9800
C13—O2	1.427 (2)	C26—O4	1.4284 (19)
C13—H13A	0.9800	C26—H26A	0.9800
C13—H13B	0.9800	C26—H26B	0.9800
C13—H13C	0.9800	C26—H26C	0.9800

C2—C1—C6	119.00 (13)	C19—C14—C20	120.04 (13)
C2—C1—C7	122.39 (13)	O3—C15—C16	124.64 (15)
C6—C1—C7	118.55 (13)	O3—C15—C14	115.09 (13)
O1—C2—C3	124.40 (15)	C16—C15—C14	120.27 (15)
O1—C2—C1	115.23 (12)	C17—C16—C15	118.74 (16)
C3—C2—C1	120.37 (15)	C17—C16—H16	120.6
C4—C3—C2	119.23 (16)	C15—C16—H16	120.6
C4—C3—H3	120.4	C16—C17—C18	122.47 (15)
C2—C3—H3	120.4	C16—C17—H17	118.8
C3—C4—C5	121.97 (15)	C18—C17—H17	118.8
C3—C4—H4	119.0	C17—C18—C19	118.76 (15)
C5—C4—H4	119.0	C17—C18—H18	120.6
C4—C5—C6	118.97 (16)	C19—C18—H18	120.6
C4—C5—H5	120.5	O4—C19—C18	125.39 (14)
C6—C5—H5	120.5	O4—C19—C14	114.32 (12)
O2—C6—C5	125.10 (15)	C18—C19—C14	120.29 (15)
O2—C6—C1	114.47 (13)	C21—C20—C14	178.63 (16)
C5—C6—C1	120.43 (15)	C20—C21—C22	178.69 (16)
C8—C7—C1	173.14 (15)	C23—C22—C24	118.91 (12)
C7—C8—C9	174.33 (15)	C23—C22—C21	120.06 (12)
C10—C9—C11	118.60 (12)	C24—C22—C21	121.03 (13)
C10—C9—C8	122.25 (13)	C24ⁱⁱ—C23—C22	120.42 (13)
C11—C9—C8	119.15 (12)	C24ⁱⁱ—C23—H23	119.8
C11ⁱ—C10—C9	120.72 (13)	C22—C23—H23	119.8
C11ⁱ—C10—H10	119.6	C23ⁱⁱ—C24—C22	120.68 (13)
C9—C10—H10	119.6	C23ⁱⁱ—C24—H24	119.7
C10ⁱ—C11—C9	120.68 (13)	C22—C24—H24	119.7
C10ⁱ—C11—H11	119.7	O3—C25—H25A	109.5
C9—C11—H11	119.7	O3—C25—H25B	109.5
O1—C12—H12A	109.5	H25A—C25—H25B	109.5
O1—C12—H12B	109.5	O3—C25—H25C	109.5
H12A—C12—H12B	109.5	H25A—C25—H25C	109.5
O1—C12—H12C	109.5	H25B—C25—H25C	109.5
H12A—C12—H12C	109.5	O4—C26—H26A	109.5
H12B—C12—H12C	109.5	O4—C26—H26B	109.5
O2—C13—H13A	109.5	H26A—C26—H26B	109.5
O2—C13—H13B	109.5	O4—C26—H26C	109.5
H13A—C13—H13B	109.5	H26A—C26—H26C	109.5
O2—C13—H13C	109.5	H26B—C26—H26C	109.5
H13A—C13—H13C	109.5	C2—O1—C12	117.87 (13)
H13B—C13—H13C	109.5	C6—O2—C13	118.48 (14)
C15—C14—C19	119.45 (13)	C15—O3—C25	117.46 (14)
C15—C14—C20	120.51 (13)	C19—O4—C26	118.12 (13)

C6—C1—C2—O1	177.73 (12)	O3—C15—C16—C17	179.04 (15)
C7—C1—C2—O1	0.57 (19)	C14—C15—C16—C17	−1.2 (2)
C6—C1—C2—C3	−1.7 (2)	C15—C16—C17—C18	0.8 (2)
C7—C1—C2—C3	−178.89 (13)	C16—C17—C18—C19	0.3 (2)
O1—C2—C3—C4	−178.42 (14)	C17—C18—C19—O4	179.83 (14)
C1—C2—C3—C4	1.0 (2)	C17—C18—C19—C14	−0.8 (2)
C2—C3—C4—C5	0.1 (2)	C15—C14—C19—O4	179.83 (12)
C3—C4—C5—C6	−0.4 (2)	C20—C14—C19—O4	−0.16 (18)
C4—C5—C6—O2	179.10 (14)	C15—C14—C19—C18	0.4 (2)
C4—C5—C6—C1	−0.4 (2)	C20—C14—C19—C18	−179.56 (13)
C2—C1—C6—O2	−178.13 (12)	C15—C14—C20—C21	−160 (7)
C7—C1—C6—O2	−0.85 (18)	C19—C14—C20—C21	20 (7)
C2—C1—C6—C5	1.4 (2)	C14—C20—C21—C22	91 (11)
C7—C1—C6—C5	178.71 (13)	C20—C21—C22—C23	2 (7)
C2—C1—C7—C8	171.6 (11)	C20—C21—C22—C24	−179 (100)
C6—C1—C7—C8	−5.6 (12)	C24—C22—C23—C24ⁱⁱ	−0.2 (2)
C1—C7—C8—C9	−13 (2)	C21—C22—C23—C24ⁱⁱ	179.38 (13)
C7—C8—C9—C10	−158.3 (14)	C23—C22—C24—C23ⁱⁱ	0.2 (2)
C7—C8—C9—C11	21.2 (15)	C21—C22—C24—C23ⁱⁱ	−179.37 (14)
C11—C9—C10—C11ⁱ	0.1 (2)	C3—C2—O1—C12	2.6 (2)
C8—C9—C10—C11ⁱ	179.59 (13)	C1—C2—O1—C12	−176.88 (14)
C10—C9—C11—C10ⁱ	−0.1 (2)	C5—C6—O2—C13	−7.5 (2)
C8—C9—C11—C10ⁱ	−179.60 (12)	C1—C6—O2—C13	171.99 (14)
C19—C14—C15—O3	−179.60 (13)	C16—C15—O3—C25	−4.4 (2)
C20—C14—C15—O3	0.4 (2)	C14—C15—O3—C25	175.75 (16)
C19—C14—C15—C16	0.6 (2)	C18—C19—O4—C26	1.0 (2)
C20—C14—C15—C16	−179.42 (14)	C14—C19—O4—C26	−178.37 (13)

Symmetry codes: (i) −x+1, −y, −z; (ii) −x+2, −y+1, −z+1.

Experimental details

Crystal data
Chemical formula	C₂₆H₂₂O₄
M_r	398.44
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	173
a, b, c (Å)	12.391 (4), 10.313 (3), 16.611 (5)
β (°)	95.323 (4)
V (Å³)	2113.5 (11)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.47 × 0.35 × 0.10

Data collection
Diffractometer	Rigaku/MSC Mercury CCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	16248, 4775, 4206
R_int	0.028
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.055, 0.120, 1.12
No. of reflections	4775
No. of parameters	271
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.20, −0.16

Computer programs: CrystalClear (Rigaku/MSC, 2001), SIR2004 (Burla et al., 2005), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2003) and Mercury (Macrae et al., 2006), WinGX (Farrugia, 1999).

Acknowledgements

This work was supported by a Grant-in-Aid for Scientific Research (grant No. 19550034) from the Ministry of Education, Culture, Sports, Science and Technology, Japan. The authors thank the Instrument Center of the Institute for Molecular Science for the X-ray structure analysis.

References

Beeby, A., Findlay, K., Low, P. J. & Marder, T. B. (2002). J. Am. Chem. Soc. 124, 8280–8284. Web of Science CrossRef PubMed CAS Google Scholar
Bunz, U. H. F. (2000). Chem. Rev. 100, 1605–1644. Web of Science CrossRef PubMed CAS Google Scholar
Bunz, U. H. F., Rubin, Y. & Tobe, Y. (1999). Chem. Soc. Rev. 28, 107–119. Web of Science CrossRef CAS Google Scholar
Burla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G. L., De Caro, L., Giacovazzo, C., Polidori, G. & Spagna, R. (2005). J. Appl. Cryst. 38, 381–388. Web of Science CrossRef CAS IUCr Journals Google Scholar
Dai, C., Nguyen, P., Marder, T. B., Scott, A. J., Clegg, W. & Viney, C. (1999). Chem. Commun. pp. 2493–2494. Web of Science CSD CrossRef Google Scholar
Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838. CrossRef CAS IUCr Journals Google Scholar
Filatov, A. S. & Petrukhina, M. A. (2005). Acta Cryst. C61, o193–o194. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Kawase, T., Seirai, Y., Darabi, H. R., Oda, M., Sarakai, Y. & Tashiro, K. (2003). Angew. Chem. Int. Ed. 42, 1621–1624. Web of Science CSD CrossRef CAS Google Scholar
Li, H., Powell, D. R., Firman, T. K. & West, R. (1998). Macromolecules, 31, 1093–1098. Web of Science CSD CrossRef CAS Google Scholar
Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453–457. Web of Science CrossRef CAS IUCr Journals Google Scholar
Moore, A. M., Dameron, A. A., Mantooth, B. A., Smith, R. K., Fuchs, D. J., Ciszek, J. W., Maya, F., Yao, Y., Tour, J. M. & Weiss, P. S. (2006). J. Am. Chem. Soc. 128, 1959–1967. Web of Science CrossRef PubMed CAS Google Scholar
Rigaku/MSC (2001). CrystalClear. Rigaku Corporation, Tokyo, Japan. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2003). J. Appl. Cryst. 36, 7–13. Web of Science CrossRef CAS IUCr Journals Google Scholar
Tour, J. M. (2000). Acc. Chem. Res. 33, 791–804. Web of Science CrossRef PubMed CAS Google Scholar
Watt, S. W., Dai, C., Scott, A. J., Burke, J. M., Thomas, R. Ll., Collings, J. C., Viney, C., Clegg, W. & Marder, T. B. (2004). Angew. Chem. Int. Ed. 43, 3061–3063. Web of Science CSD CrossRef CAS Google Scholar