7,11,15,28-Tetra­methyl-1,21,23,25-tetra­kis(2-phenyl­ethyl)resorcin[4]arene ethyl acetate clathrate

Mc Kay, M.G.; Friedrich, H.B.; Maguire, G.E.M.

doi:10.1107/S160053680705711X

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 64| Part 1| January 2008| Page o98

https://doi.org/10.1107/S160053680705711X

Open

access

7,11,15,28-Tetramethyl-1,21,23,25-tetrakis(2-phenylethyl)resorcin[4]arene ethyl acetate clathrate

Michael G. Mc Kay,^a Holger B. Friedrich ^a and Glenn E. M. Maguire ^a ^*

^aSchool of Chemistry, University of KwaZulu-Natal, Durban 4041, South Africa
^*Correspondence e-mail: maguireg@ukzn.ac.za

(Received 18 October 2007; accepted 8 November 2007; online 6 December 2007)

The title compound, C₆₈H₆₄O₈·C₄H₈O₂, is a new resorcin[4]arene cavitand synthetic precursor, obtained by alkylation of a previously reported resorcin[4]arene. The additional alkyl bridges significantly rigidify the structure and enforce a `bowl' shape on the molecular cavity. In the crystal structure, the molecule lies on a crystallographic mirror plane, and a single ethyl acetate molecule (also lying on the mirror plane) is present within the compound cavity, illustrating the host capabilities of the molecule.

Related literature

For related literature, see: Cram et al. (1988 ); Eisler et al. (2002 ); Friedrich et al. (2007 ); Piepers & Kellog (1978 ); Roman et al. (1999 ); Sebo et al. (2000 ).

Experimental

Crystal data

C₆₈H₆₄O₈·C₄H₈O₂
M_r = 1097.30
Orthorhombic, P n m a
a = 24.3288 (4) Å
b = 20.6279 (4) Å
c = 11.7828 (2) Å
V = 5913.22 (18) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 173 (2) K
0.39 × 0.27 × 0.19 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: none
49448 measured reflections
5981 independent reflections
3934 reflections with I > 2σ(I)
R_int = 0.062

Refinement

R[F² > 2σ(F²)] = 0.063
wR(F²) = 0.209
S = 1.04
5981 reflections
455 parameters
131 restraints
H-atom parameters constrained
Δρ_max = 1.16 e Å⁻³
Δρ_min = −0.55 e Å⁻³

Data collection: APEX2 (Bruker, 2005 ); cell refinement: SAINT-NT (Bruker, 2005); data reduction: SAINT-NT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: SHELXTL (Bruker, 1997 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S160053680705711X/bi2251sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S160053680705711X/bi2251Isup2.hkl

checkCIF report

Comment top

The title compound is obtained by alkylation of the hydroxyl groups of a resorcin[4]arene octol material whose structure has been previously reported (Friedrich et al., 2007). The alkylating agent, CH₂BrCl, results in the formation of four OCH₂O ether bridges between the four aromatic units of the resorcin[4]arene starting material (Fig. 1). The bridges rigidify the molecular structure, fixing the compound in a "bowl" shape (Fig. 2) with an enforced cavity that can accommodate guest molecules.

The 2-phenylethyl "feet" of the compound are orientated such that the aromatic rings are arranged in an edge-to-face manner. Such C—H···π interactions have also been observed in the resorcin[4]arene octol precursor (Friedrich et al., 2007). Interestingly, only two of the feet orientate in such a manner (Fig. 3). The presence of the ethyl acetate molecule within the molecular cavity forces the remaining two aromatic units apart, disrupting complete C—H···π interaction comparable to that as seen for the precursor. Similar disruption has also been reported previously for related structures.

Related literature top

For related literature, see: Cram et al. (1988); Eisler et al. (2002); Friedrich et al. (2007); Piepers & Kellog (1978); Roman et al. (1999); Sebo et al. (2000).

Experimental top

The synthesis of the resorcin[4]arene octol precursor can proceed via two different synthetic approaches. The older protocol as set out by Cram et al. (1988) involves heating a solution of the resorcin[4]arene starting material and the CH₂BrCl in the presence of K₂CO₃ at atmospheric pressure. Reaction proceeds over a number of days, often accompanied by addition of further equivalents of the alkylating reagent. However, since CH₂BrCl is volatile and boils at 341 K, the reaction temperature is limited to a range between 333 and 343 K. This results in yields of 40–60%. More recently, Roman et al. (1999) reported a procedure which made use of a sealed tube as a reaction vessel, heated to 361 K. The reagents are heated in the presence of Cs₂CO₃, which is used instead of K₂CO₃ due to the templating ability of the caesium cation, which aids in the formation of macrocyclic assemblies such as cavitands (Piepers & Kellog, 1978). Under these conditions, yields are in excess of 80%; indeed, the use of the protocol of Kaifer et al. in the synthesis of the resorcin[4]arene octol precursor gave a yield of 92%.

To prepare the title compound (Scheme 2): dry resorcin[4]arene octol (1.00 g, 1.66 mmol) and Cs₂CO₃ (3.00 g, 9.21 mmol) were added with stirring to dry DMSO (10 ml) in a pressure tube (ACE pressure tube, Aldrich). To the resulting pink solution, CH₂BrCl (3.00 ml, 46.0 mmol) was added followed by further DMSO (10 ml). The tube was sealed and heated at 360 K for 16 h. After cooling to room temperature, the tube contents were poured into 2% HCl (200 ml) and the voluminous solid formed was filtered and washed with water. The cream coloured solid was chromatographed on silica gel using a mobile phase of 70:30 hexane-ethyl acetate (R_f = 0.59). The fractions collected were concentrated on a rotary evaporator to yield a cream coloured solid. The solid was stirred in methanol overnight, and filtered to yield the product as a white powder (0.97 g, 92%, m.p. 418–420 K). Crystals suitable for X-ray diffraction analysis were grown by slow liquid diffusion of methanol into a solution of the title compound in 1:1 ethyl acetate:hexane.

Structure description top

For related literature, see: Cram et al. (1988); Eisler et al. (2002); Friedrich et al. (2007); Piepers & Kellog (1978); Roman et al. (1999); Sebo et al. (2000).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT-NT (Bruker, 2005); data reduction: SAINT-NT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXTL (Bruker, 1997).

Figures top

	Fig. 1. A view of one quarter of the cyclic tetramer. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as spheres of arbitrary radii. Dashed bonds indicate links to the neighbouring units.
	Fig. 2. The molecular structure with displacement ellipsoids drawn at the 50% probability level. H atoms are omitted. The "bowl" shape of the molecule is evident, with the ethyl acetate molecule present as a guest in the molecular cavity.
	Fig. 3. The relative orientation of the feet in neighbouring resorcin[4]arene units. Displacement ellipsoids are drawn at the 10% probability level. The inclusion of the ethyl acetate solvent molecule between aromatic groups is shown. H atoms are omitted.
	Fig. 4. The formation of the title compound.

7,11,15,28-Tetramethyl-1,21,23,25-tetrakis(2-phenylethyl)-2,20:3,19- dimetheno-1H,21H,23H,25H-bis[1,3]dioxocino[5,4 - i:5',4'-i']benzo[1,2 - d:5,4 - d'] bis[1,3]benzodioxocin stereoisomer top

Crystal data top

C₆₈H₆₄O₈·C₄H₈O₂	D_x = 1.233 Mg m⁻³ D_m = 1.233 Mg m⁻³ D_m measured by ?
M_r = 1097.30	Melting point: 419 K
Orthorhombic, Pnma	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2n	Cell parameters from 8201 reflections
a = 24.3288 (4) Å	θ = 2.2–27.7°
b = 20.6279 (4) Å	µ = 0.08 mm⁻¹
c = 11.7828 (2) Å	T = 173 K
V = 5913.22 (18) Å³	Block, colourless
Z = 4	0.39 × 0.27 × 0.19 mm
F(000) = 2336

Data collection top

Bruker APEXII CCD diffractometer	3934 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.062
Graphite monochromator	θ_max = 26.0°, θ_min = 1.7°
phi and ω scans	h = −29→30
49448 measured reflections	k = −25→25
5981 independent reflections	l = −14→14

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)] = 0.063	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.209	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.132P)² + 1.0228P] where P = (F_o² + 2F_c²)/3
5981 reflections	(Δ/σ)_max < 0.001
455 parameters	Δρ_max = 1.16 e Å⁻³
131 restraints	Δρ_min = −0.55 e Å⁻³

Crystal data top

C₆₈H₆₄O₈·C₄H₈O₂	V = 5913.22 (18) Å³
M_r = 1097.30	Z = 4
Orthorhombic, Pnma	Mo Kα radiation
a = 24.3288 (4) Å	µ = 0.08 mm⁻¹
b = 20.6279 (4) Å	T = 173 K
c = 11.7828 (2) Å	0.39 × 0.27 × 0.19 mm

Data collection top

Bruker APEXII CCD diffractometer	3934 reflections with I > 2σ(I)
49448 measured reflections	R_int = 0.062
5981 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.063	131 restraints
wR(F²) = 0.209	H-atom parameters constrained
S = 1.04	Δρ_max = 1.16 e Å⁻³
5981 reflections	Δρ_min = −0.55 e Å⁻³
455 parameters

Special details top

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	Occ. (<1)
C1	0.21767 (10)	0.05927 (12)	−0.0930 (2)	0.0315 (6)
C2	0.20814 (10)	0.07645 (12)	0.0196 (2)	0.0303 (5)
C3	0.16055 (10)	0.10805 (11)	0.05431 (19)	0.0281 (5)
C4	0.12187 (10)	0.12419 (11)	−0.02821 (19)	0.0282 (5)
H4	0.0899	0.1475	−0.0064	0.034*
C5	0.12871 (10)	0.10715 (12)	−0.1421 (2)	0.0296 (5)
C6	0.17667 (10)	0.07484 (12)	−0.1710 (2)	0.0325 (6)
C7	0.26893 (11)	0.02447 (15)	−0.1284 (2)	0.0429 (7)
H7A	0.2680	0.0168	−0.2104	0.064*	0.50
H7B	0.2712	−0.0171	−0.0885	0.064*	0.50
H7C	0.3011	0.0510	−0.1094	0.064*	0.50
H7D	0.2922	0.0170	−0.0617	0.064*	0.50
H7E	0.2890	0.0509	−0.1837	0.064*	0.50
H7F	0.2591	−0.0172	−0.1628	0.064*	0.50
C8	0.20493 (11)	0.09993 (15)	−0.3597 (2)	0.0408 (7)
H8A	0.2284	0.0775	−0.4161	0.049*
H8B	0.2283	0.1311	−0.3179	0.049*
C9	0.08732 (10)	0.12684 (12)	−0.2322 (2)	0.0317 (6)
H9	0.0892	0.0936	−0.2938	0.038*
C10	0.16631 (14)	0.2500	−0.4127 (3)	0.0384 (9)
C11	0.14567 (10)	0.19219 (14)	−0.36868 (19)	0.0341 (6)
C12	0.10640 (9)	0.19097 (13)	−0.28304 (19)	0.0312 (6)
C13	0.08815 (13)	0.2500	−0.2412 (3)	0.0286 (7)
H13	0.0620	0.2500	−0.1812	0.034*
C14	0.20920 (17)	0.2500	−0.5051 (3)	0.0487 (11)
H14A	0.2431	0.2699	−0.4765	0.073*	0.50
H14B	0.1957	0.2748	−0.5703	0.073*	0.50
H14C	0.2168	0.2053	−0.5285	0.073*	0.50
C15	0.26710 (13)	0.2500	0.2326 (3)	0.0304 (8)
C16	0.23792 (9)	0.19246 (12)	0.22008 (18)	0.0279 (5)
C17	0.18192 (9)	0.19104 (11)	0.19712 (18)	0.0260 (5)
C18	0.15503 (13)	0.2500	0.1853 (3)	0.0266 (7)
H18	0.1168	0.2500	0.1684	0.032*
C19	0.32741 (15)	0.2500	0.2608 (3)	0.0411 (9)
H19A	0.3402	0.2052	0.2698	0.062*	0.50
H19B	0.3334	0.2738	0.3318	0.062*	0.50
H19C	0.3479	0.2710	0.1994	0.062*	0.50
C20	0.28457 (10)	0.10094 (13)	0.1404 (2)	0.0343 (6)
H20A	0.2923	0.1328	0.0797	0.041*
H20B	0.3194	0.0783	0.1584	0.041*
C21	0.15301 (9)	0.12615 (12)	0.17830 (19)	0.0278 (5)
H21	0.1734	0.0931	0.2239	0.033*
C22	0.02798 (10)	0.12884 (12)	−0.1903 (2)	0.0352 (6)
H22A	0.0254	0.1599	−0.1264	0.042*
H22B	0.0043	0.1452	−0.2523	0.042*
C23	0.00637 (11)	0.06397 (14)	−0.1517 (3)	0.0493 (8)
H23A	0.0018	0.0354	−0.2185	0.059*
H23B	0.0336	0.0436	−0.1005	0.059*
C24	−0.04747 (11)	0.06929 (13)	−0.0909 (3)	0.0411 (7)
C25	−0.04889 (13)	0.08805 (16)	0.0217 (3)	0.0550 (8)
H25	−0.0153	0.0962	0.0603	0.066*
C26	−0.09799 (15)	0.09521 (18)	0.0792 (3)	0.0638 (9)
H26	−0.0979	0.1084	0.1565	0.077*
C27	−0.14716 (14)	0.08316 (18)	0.0247 (3)	0.0644 (9)
H27	−0.1811	0.0880	0.0638	0.077*
C28	−0.14632 (13)	0.06401 (17)	−0.0874 (4)	0.0638 (10)
H28	−0.1799	0.0552	−0.1256	0.077*
C29	−0.09712 (12)	0.05752 (14)	−0.1446 (3)	0.0496 (7)
H29	−0.0973	0.0448	−0.2221	0.060*
C30	0.09333 (10)	0.12443 (13)	0.21862 (19)	0.0315 (6)
H30A	0.0728	0.1603	0.1824	0.038*
H30B	0.0763	0.0831	0.1942	0.038*
C31	0.0885 (2)	0.1305 (6)	0.3468 (3)	0.046 (3)	0.461 (5)
H31A	0.1150	0.1004	0.3826	0.055*	0.461 (5)
H31B	0.0989	0.1751	0.3692	0.055*	0.461 (5)
C32	0.0316 (5)	0.1161 (4)	0.393 (2)	0.048 (2)	0.461 (5)
C33	−0.0079 (3)	0.1621 (4)	0.3928 (8)	0.077 (2)	0.461 (5)
H33	0.0007	0.2041	0.3648	0.092*	0.461 (5)
C34	−0.0606 (3)	0.1497 (5)	0.4325 (10)	0.093 (3)	0.461 (5)
H34	−0.0881	0.1823	0.4277	0.112*	0.461 (5)
C35	−0.0726 (4)	0.0909 (6)	0.4783 (12)	0.093 (3)	0.461 (5)
H35	−0.1069	0.0837	0.5144	0.112*	0.461 (5)
C36	−0.0355 (3)	0.0434 (4)	0.4718 (9)	0.096 (3)	0.461 (5)
H36	−0.0452	0.0009	0.4959	0.115*	0.461 (5)
C37	0.0170 (3)	0.0552 (4)	0.4304 (8)	0.077 (2)	0.461 (5)
H37	0.0431	0.0210	0.4280	0.092*	0.461 (5)
C31A	0.0893 (2)	0.1308 (5)	0.3470 (3)	0.049 (3)	0.539 (5)
H31C	0.1101	0.0949	0.3823	0.058*	0.539 (5)
H31D	0.1071	0.1719	0.3701	0.058*	0.539 (5)
C32A	0.0310 (4)	0.1300 (4)	0.3930 (18)	0.049 (2)	0.539 (5)
C33A	0.0156 (2)	0.1708 (4)	0.4765 (5)	0.0705 (18)	0.539 (5)
H33A	0.0416	0.2008	0.5057	0.085*	0.539 (5)
C34A	−0.0371 (3)	0.1703 (4)	0.5210 (6)	0.088 (2)	0.539 (5)
H34A	−0.0471	0.2007	0.5781	0.105*	0.539 (5)
C35A	−0.0746 (3)	0.1265 (6)	0.4831 (9)	0.081 (2)	0.539 (5)
H35A	−0.1099	0.1236	0.5172	0.097*	0.539 (5)
C36A	−0.0609 (2)	0.0877 (5)	0.3972 (7)	0.088 (2)	0.539 (5)
H36A	−0.0874	0.0582	0.3680	0.105*	0.539 (5)
C37A	−0.0088 (2)	0.0896 (4)	0.3497 (6)	0.076 (2)	0.539 (5)
H37A	−0.0004	0.0626	0.2866	0.091*	0.539 (5)
C38	0.2894 (2)	0.2500	−0.1267 (4)	0.0743 (16)
C39	0.22971 (16)	0.2500	−0.1041 (3)	0.0427 (9)
H39A	0.2233	0.2500	−0.0220	0.064*
H39B	0.2131	0.2112	−0.1378	0.064*
C40	0.3641 (3)	0.2500	−0.2541 (6)	0.159 (5)
H40	0.3816	0.2111	−0.2208	0.190*
C41	0.3703 (4)	0.2500	−0.3809 (6)	0.131 (3)
H41A	0.4096	0.2500	−0.3991	0.197*
H41B	0.3531	0.2112	−0.4132	0.197*
O1	0.18418 (7)	0.05391 (9)	−0.28283 (14)	0.0395 (5)
O2	0.16347 (7)	0.13445 (10)	−0.41755 (14)	0.0413 (5)
O3	0.26603 (7)	0.13439 (8)	0.23871 (14)	0.0326 (4)
O4	0.24595 (7)	0.05531 (8)	0.10003 (14)	0.0337 (4)
O5	0.30466 (17)	0.2500	−0.2313 (3)	0.1016 (15)
O6	0.3238 (2)	0.2500	−0.0520 (5)	0.223 (5)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0301 (13)	0.0327 (13)	0.0318 (13)	0.0041 (10)	0.0041 (10)	−0.0017 (10)
C2	0.0305 (12)	0.0308 (12)	0.0296 (12)	0.0014 (10)	−0.0035 (10)	0.0013 (10)
C3	0.0303 (12)	0.0295 (12)	0.0245 (12)	−0.0034 (10)	0.0016 (10)	−0.0013 (10)
C4	0.0278 (12)	0.0301 (12)	0.0267 (12)	−0.0002 (10)	0.0031 (10)	−0.0021 (10)
C5	0.0297 (13)	0.0323 (13)	0.0269 (12)	−0.0018 (10)	−0.0012 (10)	−0.0050 (10)
C6	0.0368 (14)	0.0347 (13)	0.0260 (12)	0.0013 (11)	0.0017 (10)	−0.0081 (10)
C7	0.0418 (15)	0.0517 (17)	0.0351 (14)	0.0139 (13)	0.0023 (12)	−0.0069 (13)
C8	0.0334 (14)	0.0619 (19)	0.0272 (13)	0.0097 (12)	0.0024 (11)	−0.0095 (13)
C9	0.0267 (12)	0.0423 (14)	0.0260 (12)	−0.0013 (10)	−0.0026 (10)	−0.0098 (10)
C10	0.0302 (19)	0.071 (3)	0.0140 (15)	0.000	−0.0018 (14)	0.000
C11	0.0295 (13)	0.0571 (17)	0.0155 (11)	0.0039 (11)	−0.0042 (9)	−0.0055 (11)
C12	0.0247 (12)	0.0508 (16)	0.0180 (11)	0.0003 (10)	−0.0069 (9)	−0.0043 (10)
C13	0.0234 (16)	0.043 (2)	0.0195 (15)	0.000	−0.0005 (13)	0.000
C14	0.043 (2)	0.079 (3)	0.0242 (18)	0.000	0.0088 (17)	0.000
C15	0.0264 (17)	0.046 (2)	0.0186 (16)	0.000	0.0009 (13)	0.000
C16	0.0303 (12)	0.0368 (13)	0.0165 (11)	0.0041 (10)	−0.0006 (9)	0.0011 (9)
C17	0.0282 (12)	0.0357 (13)	0.0141 (10)	−0.0017 (10)	0.0019 (9)	0.0006 (9)
C18	0.0245 (16)	0.0385 (19)	0.0167 (15)	0.000	0.0016 (12)	0.000
C19	0.0290 (19)	0.053 (2)	0.041 (2)	0.000	−0.0064 (16)	0.000
C20	0.0271 (12)	0.0414 (15)	0.0346 (13)	0.0056 (11)	−0.0004 (10)	0.0007 (11)
C21	0.0288 (12)	0.0323 (13)	0.0223 (11)	0.0006 (10)	0.0015 (9)	0.0031 (10)
C22	0.0292 (13)	0.0400 (14)	0.0363 (14)	−0.0018 (11)	−0.0026 (11)	−0.0073 (11)
C23	0.0362 (15)	0.0434 (17)	0.068 (2)	−0.0046 (12)	0.0020 (14)	−0.0102 (15)
C24	0.0340 (14)	0.0331 (14)	0.0563 (18)	−0.0047 (11)	−0.0008 (13)	0.0004 (13)
C25	0.0474 (18)	0.060 (2)	0.058 (2)	−0.0049 (15)	−0.0041 (15)	0.0011 (16)
C26	0.067 (2)	0.069 (2)	0.056 (2)	−0.0032 (18)	0.0135 (18)	0.0028 (17)
C27	0.0484 (19)	0.064 (2)	0.081 (3)	−0.0070 (16)	0.0186 (18)	0.0097 (19)
C28	0.0338 (16)	0.068 (2)	0.090 (3)	−0.0104 (15)	−0.0009 (17)	0.000 (2)
C29	0.0420 (16)	0.0476 (17)	0.0592 (19)	−0.0079 (13)	−0.0026 (14)	−0.0054 (14)
C30	0.0292 (13)	0.0404 (14)	0.0249 (12)	−0.0038 (11)	0.0008 (10)	0.0008 (10)
C31	0.033 (4)	0.085 (8)	0.020 (7)	−0.019 (4)	−0.001 (4)	−0.015 (6)
C32	0.034 (3)	0.081 (4)	0.031 (4)	−0.010 (3)	0.005 (3)	0.003 (5)
C33	0.056 (4)	0.097 (4)	0.079 (5)	0.010 (3)	0.024 (4)	0.021 (4)
C34	0.048 (4)	0.133 (6)	0.098 (6)	0.019 (4)	0.020 (4)	0.027 (5)
C35	0.053 (4)	0.148 (6)	0.079 (6)	−0.011 (4)	0.019 (4)	0.029 (6)
C36	0.067 (4)	0.117 (5)	0.102 (6)	−0.023 (3)	0.023 (4)	0.044 (5)
C37	0.060 (4)	0.091 (4)	0.079 (5)	−0.007 (3)	0.022 (4)	0.028 (4)
C31A	0.038 (4)	0.075 (7)	0.033 (7)	0.000 (4)	0.008 (4)	0.010 (5)
C32A	0.033 (3)	0.082 (4)	0.030 (4)	−0.002 (3)	0.003 (3)	0.006 (4)
C33A	0.041 (3)	0.129 (5)	0.042 (3)	0.010 (3)	−0.001 (2)	−0.019 (3)
C34A	0.048 (3)	0.163 (6)	0.053 (4)	0.017 (3)	0.008 (3)	−0.021 (4)
C35A	0.036 (3)	0.150 (6)	0.058 (4)	0.010 (3)	0.011 (3)	0.013 (4)
C36A	0.038 (3)	0.130 (6)	0.095 (5)	−0.014 (3)	0.010 (3)	−0.008 (4)
C37A	0.048 (3)	0.097 (5)	0.083 (4)	−0.017 (3)	0.019 (3)	−0.018 (3)
C38	0.059 (3)	0.119 (5)	0.046 (3)	0.000	−0.006 (2)	0.000
C39	0.047 (2)	0.046 (2)	0.035 (2)	0.000	−0.0041 (17)	0.000
C40	0.076 (5)	0.308 (15)	0.092 (6)	0.000	0.006 (4)	0.000
C41	0.134 (7)	0.119 (7)	0.140 (8)	0.000	0.055 (6)	0.000
O1	0.0422 (11)	0.0478 (11)	0.0286 (9)	0.0067 (8)	0.0018 (8)	−0.0136 (8)
O2	0.0390 (10)	0.0638 (13)	0.0210 (8)	0.0101 (9)	−0.0026 (7)	−0.0125 (8)
O3	0.0328 (9)	0.0400 (10)	0.0249 (8)	0.0070 (7)	−0.0022 (7)	0.0038 (7)
O4	0.0351 (9)	0.0342 (9)	0.0317 (9)	0.0057 (7)	−0.0045 (7)	0.0020 (7)
O5	0.065 (2)	0.173 (5)	0.067 (3)	0.000	0.004 (2)	0.000
O6	0.074 (3)	0.515 (16)	0.081 (4)	0.000	−0.010 (3)	0.000

Geometric parameters (Å, º) top

C1—C2	1.392 (3)	C23—C24	1.497 (4)
C1—C6	1.394 (3)	C23—H23A	0.990
C1—C7	1.498 (3)	C23—H23B	0.990
C2—C3	1.390 (3)	C24—C25	1.382 (4)
C2—O4	1.391 (3)	C24—C29	1.385 (4)
C3—C4	1.394 (3)	C25—C26	1.382 (4)
C3—C21	1.519 (3)	C25—H25	0.950
C4—C5	1.397 (3)	C26—C27	1.380 (5)
C4—H4	0.950	C26—H26	0.950
C5—C6	1.387 (3)	C27—C28	1.379 (5)
C5—C9	1.519 (3)	C27—H27	0.950
C6—O1	1.398 (3)	C28—C29	1.380 (4)
C7—H7A	0.980	C28—H28	0.950
C7—H7B	0.980	C29—H29	0.950
C7—H7C	0.980	C30—C31	1.521 (4)
C7—H7D	0.980	C30—C31A	1.522 (4)
C7—H7E	0.980	C30—H30A	0.990
C7—H7F	0.980	C30—H30B	0.990
C8—O1	1.406 (3)	C31—C32	1.517 (5)
C8—O2	1.410 (3)	C31—H31A	0.990
C8—H8A	0.990	C31—H31B	0.990
C8—H8B	0.990	C32—C33	1.349 (13)
C9—C12	1.525 (4)	C32—C37	1.378 (13)
C9—C22	1.526 (3)	C33—C34	1.388 (7)
C9—H9	1.000	C33—H33	0.950
C10—C11	1.394 (3)	C34—C35	1.360 (12)
C10—C11ⁱ	1.394 (3)	C34—H34	0.950
C10—C14	1.508 (5)	C35—C36	1.334 (12)
C11—C12	1.390 (3)	C35—H35	0.950
C11—O2	1.392 (3)	C36—C37	1.389 (7)
C12—C13	1.387 (3)	C36—H36	0.950
C13—C12ⁱ	1.387 (3)	C37—H37	0.950
C13—H13	0.950	C31A—C32A	1.517 (5)
C14—H14A	0.980	C31A—H31C	0.990
C14—H14B	0.980	C31A—H31D	0.990
C14—H14C	0.980	C32A—C33A	1.350 (13)
C15—C16	1.391 (3)	C32A—C37A	1.375 (13)
C15—C16ⁱ	1.391 (3)	C33A—C34A	1.384 (7)
C15—C19	1.505 (5)	C33A—H33A	0.950
C16—C17	1.389 (3)	C34A—C35A	1.360 (12)
C16—O3	1.397 (3)	C34A—H34A	0.950
C17—C18	1.388 (3)	C35A—C36A	1.332 (12)
C17—C21	1.528 (3)	C35A—H35A	0.950
C18—C17ⁱ	1.388 (3)	C36A—C37A	1.388 (7)
C18—H18	0.950	C36A—H36A	0.950
C19—H19A	0.980	C37A—H37A	0.950
C19—H19B	0.980	C38—O6	1.213 (7)
C19—H19C	0.980	C38—O5	1.286 (6)
C20—O4	1.412 (3)	C38—C39	1.477 (6)
C20—O3	1.422 (3)	C39—H39A	0.980
C20—H20A	0.990	C39—H39B	0.980
C20—H20B	0.990	C40—O5	1.470 (8)
C21—C30	1.528 (3)	C40—C41	1.503 (5)
C21—H21	1.000	C40—H40	0.990
C22—C23	1.508 (4)	C41—H41A	0.980
C22—H22A	0.990	C41—H41B	0.980
C22—H22B	0.990

C2—C1—C6	116.8 (2)	C23—C22—H22B	108.8
C2—C1—C7	121.7 (2)	C9—C22—H22B	108.8
C6—C1—C7	121.5 (2)	H22A—C22—H22B	107.7
C3—C2—O4	119.8 (2)	C24—C23—C22	112.6 (2)
C3—C2—C1	122.6 (2)	C24—C23—H23A	109.1
O4—C2—C1	117.3 (2)	C22—C23—H23A	109.1
C2—C3—C4	118.0 (2)	C24—C23—H23B	109.1
C2—C3—C21	119.9 (2)	C22—C23—H23B	109.1
C4—C3—C21	122.1 (2)	H23A—C23—H23B	107.8
C3—C4—C5	122.0 (2)	C25—C24—C29	117.8 (3)
C3—C4—H4	119.0	C25—C24—C23	120.1 (3)
C5—C4—H4	119.0	C29—C24—C23	122.1 (3)
C6—C5—C4	117.2 (2)	C26—C25—C24	121.5 (3)
C6—C5—C9	121.0 (2)	C26—C25—H25	119.2
C4—C5—C9	121.7 (2)	C24—C25—H25	119.2
C5—C6—C1	123.4 (2)	C27—C26—C25	120.1 (3)
C5—C6—O1	119.4 (2)	C27—C26—H26	119.9
C1—C6—O1	117.2 (2)	C25—C26—H26	119.9
C1—C7—H7A	109.5	C28—C27—C26	119.0 (3)
C1—C7—H7B	109.5	C28—C27—H27	120.5
H7A—C7—H7B	109.5	C26—C27—H27	120.5
C1—C7—H7C	109.5	C27—C28—C29	120.6 (3)
H7A—C7—H7C	109.5	C27—C28—H28	119.7
H7B—C7—H7C	109.5	C29—C28—H28	119.7
C1—C7—H7D	109.5	C28—C29—C24	121.1 (3)
H7A—C7—H7D	141.1	C28—C29—H29	119.5
H7B—C7—H7D	56.3	C24—C29—H29	119.5
H7C—C7—H7D	56.3	C31—C30—C21	112.4 (3)
C1—C7—H7E	109.5	C31A—C30—C21	111.6 (3)
H7A—C7—H7E	56.3	C31—C30—H30A	109.1
H7B—C7—H7E	141.1	C31A—C30—H30A	109.3
H7C—C7—H7E	56.3	C21—C30—H30A	109.1
H7D—C7—H7E	109.5	C31—C30—H30B	109.1
C1—C7—H7F	109.5	C31A—C30—H30B	109.7
H7A—C7—H7F	56.3	C21—C30—H30B	109.1
H7B—C7—H7F	56.3	H30A—C30—H30B	107.9
H7C—C7—H7F	141.1	C32—C31—C30	114.2 (10)
H7D—C7—H7F	109.5	C32—C31—H31A	108.7
H7E—C7—H7F	109.5	C30—C31—H31A	108.7
O1—C8—O2	113.3 (2)	C32—C31—H31B	108.7
O1—C8—H8A	108.9	C30—C31—H31B	108.7
O2—C8—H8A	108.9	H31A—C31—H31B	107.6
O1—C8—H8B	108.9	C33—C32—C37	117.3 (5)
O2—C8—H8B	108.9	C33—C32—C31	120.8 (10)
H8A—C8—H8B	107.7	C37—C32—C31	121.8 (9)
C5—C9—C12	107.77 (19)	C32—C33—C34	121.8 (7)
C5—C9—C22	114.1 (2)	C32—C33—H33	119.1
C12—C9—C22	113.1 (2)	C34—C33—H33	119.1
C5—C9—H9	107.2	C35—C34—C33	119.7 (7)
C12—C9—H9	107.2	C35—C34—H34	120.2
C22—C9—H9	107.2	C33—C34—H34	120.2
C11—C10—C11ⁱ	117.6 (3)	C36—C35—C34	119.2 (6)
C11—C10—C14	121.18 (15)	C36—C35—H35	120.4
C11ⁱ—C10—C14	121.18 (15)	C34—C35—H35	120.4
C12—C11—O2	119.9 (2)	C35—C36—C37	120.8 (7)
C12—C11—C10	122.2 (2)	C35—C36—H36	119.6
O2—C11—C10	117.8 (2)	C37—C36—H36	119.6
C13—C12—C11	117.6 (2)	C32—C37—C36	120.6 (7)
C13—C12—C9	121.6 (2)	C32—C37—H37	119.7
C11—C12—C9	120.7 (2)	C36—C37—H37	119.7
C12ⁱ—C13—C12	122.8 (3)	C32A—C31A—C30	114.5 (9)
C12ⁱ—C13—H13	118.6	C32A—C31A—H31C	108.6
C12—C13—H13	118.6	C30—C31A—H31C	108.6
C10—C14—H14A	109.5	C32A—C31A—H31D	108.6
C10—C14—H14B	109.5	C30—C31A—H31D	108.6
H14A—C14—H14B	109.5	H31C—C31A—H31D	107.6
C10—C14—H14C	109.5	C33A—C32A—C37A	116.9 (5)
H14A—C14—H14C	109.5	C33A—C32A—C31A	120.9 (9)
H14B—C14—H14C	109.5	C37A—C32A—C31A	122.2 (9)
C16—C15—C16ⁱ	117.2 (3)	C32A—C33A—C34A	122.0 (7)
C16—C15—C19	121.41 (15)	C32A—C33A—H33A	119.0
C16ⁱ—C15—C19	121.41 (15)	C34A—C33A—H33A	119.0
C17—C16—C15	122.6 (2)	C35A—C34A—C33A	120.1 (7)
C17—C16—O3	119.5 (2)	C35A—C34A—H34A	119.9
C15—C16—O3	117.7 (2)	C33A—C34A—H34A	119.9
C18—C17—C16	117.6 (2)	C36A—C35A—C34A	118.8 (5)
C18—C17—C21	122.4 (2)	C36A—C35A—H35A	120.6
C16—C17—C21	119.9 (2)	C34A—C35A—H35A	120.6
C17ⁱ—C18—C17	122.4 (3)	C35A—C36A—C37A	121.2 (7)
C17ⁱ—C18—H18	118.8	C35A—C36A—H36A	119.4
C17—C18—H18	118.8	C37A—C36A—H36A	119.4
C15—C19—H19A	109.5	C32A—C37A—C36A	120.7 (7)
C15—C19—H19B	109.5	C32A—C37A—H37A	119.6
H19A—C19—H19B	109.5	C36A—C37A—H37A	119.6
C15—C19—H19C	109.5	O6—C38—O5	119.8 (5)
H19A—C19—H19C	109.5	O6—C38—C39	123.1 (5)
H19B—C19—H19C	109.5	O5—C38—C39	117.1 (4)
O4—C20—O3	112.75 (19)	C38—C39—H39A	109.5
O4—C20—H20A	109.0	C38—C39—H39B	109.4
O3—C20—H20A	109.0	H39A—C39—H39B	109.5
O4—C20—H20B	109.0	O5—C40—C41	106.3 (6)
O3—C20—H20B	109.0	O5—C40—H40	110.6
H20A—C20—H20B	107.8	C41—C40—H40	110.5
C3—C21—C30	114.09 (19)	C40—C41—H41A	108.4
C3—C21—C17	107.41 (18)	C40—C41—H41B	110.0
C30—C21—C17	114.4 (2)	H41A—C41—H41B	109.5
C3—C21—H21	106.8	C6—O1—C8	116.5 (2)
C30—C21—H21	106.8	C11—O2—C8	117.04 (19)
C17—C21—H21	106.8	C16—O3—C20	116.33 (17)
C23—C22—C9	113.8 (2)	C2—O4—C20	117.43 (18)
C23—C22—H22A	108.8	C38—O5—C40	117.2 (5)
C9—C22—H22A	108.8

C6—C1—C2—C3	−0.5 (4)	C5—C9—C22—C23	−62.8 (3)
C7—C1—C2—C3	−179.2 (2)	C12—C9—C22—C23	173.6 (2)
C6—C1—C2—O4	173.5 (2)	C9—C22—C23—C24	169.1 (2)
C7—C1—C2—O4	−5.2 (4)	C22—C23—C24—C25	−79.7 (4)
O4—C2—C3—C4	−175.4 (2)	C22—C23—C24—C29	98.6 (3)
C1—C2—C3—C4	−1.6 (4)	C29—C24—C25—C26	−0.3 (5)
O4—C2—C3—C21	6.9 (3)	C23—C24—C25—C26	178.1 (3)
C1—C2—C3—C21	−179.3 (2)	C24—C25—C26—C27	0.4 (5)
C2—C3—C4—C5	2.7 (3)	C25—C26—C27—C28	0.0 (5)
C21—C3—C4—C5	−179.6 (2)	C26—C27—C28—C29	−0.6 (5)
C3—C4—C5—C6	−1.8 (4)	C27—C28—C29—C24	0.7 (5)
C3—C4—C5—C9	−177.9 (2)	C25—C24—C29—C28	−0.3 (4)
C4—C5—C6—C1	−0.4 (4)	C23—C24—C29—C28	−178.7 (3)
C9—C5—C6—C1	175.8 (2)	C3—C21—C30—C31	169.4 (5)
C4—C5—C6—O1	176.8 (2)	C17—C21—C30—C31	−66.4 (6)
C9—C5—C6—O1	−7.0 (4)	C3—C21—C30—C31A	169.6 (5)
C2—C1—C6—C5	1.5 (4)	C17—C21—C30—C31A	−66.1 (5)
C7—C1—C6—C5	−179.8 (2)	C31A—C30—C31—C32	176 (100)
C2—C1—C6—O1	−175.8 (2)	C21—C30—C31—C32	−168.8 (7)
C7—C1—C6—O1	2.9 (4)	C30—C31—C32—C33	−82.8 (17)
C6—C5—C9—C12	−83.5 (3)	C30—C31—C32—C37	93 (2)
C4—C5—C9—C12	92.5 (3)	C37—C32—C33—C34	2 (3)
C6—C5—C9—C22	150.1 (2)	C31—C32—C33—C34	178.7 (13)
C4—C5—C9—C22	−33.9 (3)	C32—C33—C34—C35	3 (2)
C11ⁱ—C10—C11—C12	−0.8 (5)	C33—C34—C35—C36	−8 (2)
C14—C10—C11—C12	179.6 (3)	C34—C35—C36—C37	7 (2)
C11ⁱ—C10—C11—O2	175.83 (17)	C33—C32—C37—C36	−3 (3)
C14—C10—C11—O2	−3.8 (4)	C31—C32—C37—C36	−179.8 (13)
O2—C11—C12—C13	−176.9 (2)	C35—C36—C37—C32	−1 (2)
C10—C11—C12—C13	−0.4 (4)	C31—C30—C31A—C32A	−15 (67)
O2—C11—C12—C9	7.2 (3)	C21—C30—C31A—C32A	179.6 (6)
C10—C11—C12—C9	−176.3 (2)	C30—C31A—C32A—C33A	−138.5 (14)
C5—C9—C12—C13	−92.7 (3)	C30—C31A—C32A—C37A	39.3 (17)
C22—C9—C12—C13	34.3 (3)	C37A—C32A—C33A—C34A	3 (2)
C5—C9—C12—C11	83.1 (3)	C31A—C32A—C33A—C34A	−179.1 (10)
C22—C9—C12—C11	−149.9 (2)	C32A—C33A—C34A—C35A	2.0 (16)
C11—C12—C13—C12ⁱ	1.6 (5)	C33A—C34A—C35A—C36A	−4.9 (15)
C9—C12—C13—C12ⁱ	177.53 (19)	C34A—C35A—C36A—C37A	2.7 (17)
C16ⁱ—C15—C16—C17	−0.6 (4)	C33A—C32A—C37A—C36A	−5 (2)
C19—C15—C16—C17	178.2 (3)	C31A—C32A—C37A—C36A	176.9 (11)
C16ⁱ—C15—C16—O3	−176.47 (16)	C35A—C36A—C37A—C32A	2.5 (17)
C19—C15—C16—O3	2.2 (4)	C5—C6—O1—C8	84.0 (3)
C15—C16—C17—C18	0.7 (4)	C1—C6—O1—C8	−98.7 (3)
O3—C16—C17—C18	176.6 (2)	O2—C8—O1—C6	−92.1 (3)
C15—C16—C17—C21	176.8 (2)	C12—C11—O2—C8	−82.9 (3)
O3—C16—C17—C21	−7.3 (3)	C10—C11—O2—C8	100.4 (3)
C16—C17—C18—C17ⁱ	−0.9 (4)	O1—C8—O2—C11	91.4 (3)
C21—C17—C18—C17ⁱ	−176.90 (17)	C17—C16—O3—C20	84.4 (3)
C2—C3—C21—C30	−147.6 (2)	C15—C16—O3—C20	−99.6 (3)
C4—C3—C21—C30	34.7 (3)	O4—C20—O3—C16	−91.5 (2)
C2—C3—C21—C17	84.5 (3)	C3—C2—O4—C20	−83.6 (3)
C4—C3—C21—C17	−93.1 (3)	C1—C2—O4—C20	102.3 (3)
C18—C17—C21—C3	91.1 (3)	O3—C20—O4—C2	91.1 (2)
C16—C17—C21—C3	−84.8 (2)	O6—C38—O5—C40	0.0
C18—C17—C21—C30	−36.6 (3)	C39—C38—O5—C40	180.0
C16—C17—C21—C30	147.5 (2)	C41—C40—O5—C38	180.0

Symmetry code: (i) x, −y+1/2, z.

Experimental details

Crystal data
Chemical formula	C₆₈H₆₄O₈·C₄H₈O₂
M_r	1097.30
Crystal system, space group	Orthorhombic, Pnma
Temperature (K)	173
a, b, c (Å)	24.3288 (4), 20.6279 (4), 11.7828 (2)
V (Å³)	5913.22 (18)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.39 × 0.27 × 0.19

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	49448, 5981, 3934
R_int	0.062
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.063, 0.209, 1.04
No. of reflections	5981
No. of parameters	455
No. of restraints	131
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.16, −0.55

Computer programs: APEX2 (Bruker, 2005), SAINT-NT (Bruker, 2005), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEP-3 for Windows (Farrugia, 1997), SHELXTL (Bruker, 1997).

Acknowledgements

The financial support of the DST–NRF Centre of Excellence in Catalysis, c*change, is duly acknowledged. Our thanks go to Dr Manuel Fernandes at the University of the Witwatersrand for performing the data acquisition and structure solution.

References

Bruker (1997). SHELXTL. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Bruker (2005). APEX2 (Version 2.0-1) and SAINT-NT (Version 6.0). Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Cram, D. J., Karbach, S., Kim, H.-E., Knobler, C. B., Maverick, E. F., Ericson, J. L. & Helgeson, R. C. (1988). J. Am. Chem. Soc. 110, 2229–2237. CSD CrossRef CAS Web of Science Google Scholar
Eisler, D., Hong, W., Jennings, M. C. & Pudephatt, R. J. (2002). Organometallics, 21, 3955–3960. Web of Science CSD CrossRef CAS Google Scholar
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Friedrich, H. B., Howie, R. A., Maguire, G. E. M. & Mc Kay, M. G. (2007). Acta Cryst. E63, o4346. Web of Science CSD CrossRef IUCr Journals Google Scholar
Piepers, O. & Kellog, R. M. (1978). J. Chem. Soc. Chem. Commun. pp. 383–384. CrossRef Web of Science Google Scholar
Roman, E., Peinador, C., Mendoza, S. & Kaifer, A. E. (1999). J. Org. Chem. 64, 2577–2578. Web of Science CrossRef CAS Google Scholar
Sebo, L., Diederich, F. & Gramlich, V. (2000). Helv. Chim. Acta, 83, 93–96. CrossRef CAS Google Scholar
Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany. Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.