rac-7,7′,9,9′-Tetra­phenyl-9a,9a′-bi(7,8,9,9a-tetra­hydro-6aH-penta­leno[1,2,3-ij]naphthalen-8-one)

Zhang, X.; Ye, J.; Gong, W.; Lin, Y.; Ning, G.

doi:10.1107/S1600536812014146

organic compounds

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ISSN: 2056-9890

Volume 68| Part 5| May 2012| Page o1329

doi:10.1107/S1600536812014146

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rac-7,7′,9,9′-Tetraphenyl-9a,9a′-bi(7,8,9,9a-tetrahydro-6aH-pentaleno[1,2,3-ij]naphthalen-8-one)

Xiangdong Zhang,^a Junwei Ye,^a Weitao Gong,^a Yuan Lin ^a and Guiling Ning ^a ^*

^aState Key Laboratory of Fine Chemicals and School of Chemical Engineering, Dalian University of Technology, Dalian 116012, People's Republic of China
^*Correspondence e-mail: ninggl@dlut.edu.cn

(Received 8 March 2012; accepted 1 April 2012; online 6 April 2012)

The racemic title compound, C₅₄H₃₈O₂, consists of two C-linked pentaleno[1,2,3-ij]naphthalenone moieties, the crowded aryl ring substitution on the cyclopentane rings forcing the two segments to assume a conformation which has pseudo-twofold rotational symmetry, with a dihedral angle between the naphthalene substituent groups of 55.30 (8)°. In each segment, the two phenyl rings have different conformational orientations, with inter-ring dihedral angles of 34.7 (2) and 49.63 (16)°. Each cyclopentane ring has the same relative configuration in its four chiral centres and together with the fused naphthalene ring assumes an overall chair-like conformation.

Related literature

For photoluminescence properties of naphthalene compounds, see: Cai et al. (2010 ); Haneline et al. (2002 ); Koning et al. (2003 ); Tsubaki et al. (2006 ). For a related structure, see: Dyker (1993 ).

Experimental

Crystal data

C₅₄H₃₈O₂
M_r = 718.84
Monoclinic, P 2₁ /c
a = 14.325 (3) Å
b = 13.448 (3) Å
c = 19.914 (4) Å
β = 101.449 (5)°
V = 3759.9 (14) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 275 K
0.23 × 0.22 × 0.19 mm

Data collection

Bruker CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.983, T_max = 0.986
42062 measured reflections
8342 independent reflections
4812 reflections with I > 2σ(I)
R_int = 0.051

Refinement

R[F² > 2σ(F²)] = 0.066
wR(F²) = 0.161
S = 1.05
8342 reflections
505 parameters
H-atom parameters constrained
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Data collection: SMART (Bruker, 1997 ); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812014146/zs2187sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812014146/zs2187Isup2.hkl

checkCIF report

Comment top

Naphthalene derivatives have attracted considerable attention because of their superb photoluminescence (PL) performance (Cai et al., 2010; Haneline et al., 2002; Koning et al., 2003; Tsubaki et al., 2006). The investigation of structures of nonplanar naphthalene derivatives therefore constitutes a significant thrust in PL materials research. In the present study, a naphthalene and phenyl substituted cyclopentanone compound C₅₄H₃₈O₂ has been synthesized and its crystal structure is reported here. A similar structure with half the skeleton of the title compound has been reported (Dyker, 1993).

The racemic title compound (Fig. 1) consists of two C-linked 2,5-diphenyl-3,4-naphthylcyclopentan-1-one moieties, the linking bond [C3—C3' = 1.578 (3) Å] being elongated due to the steric crowding afforded by the aryl ring substituents on the cyclopentane rings. The two segments assume a conformation which gives the molecule pseudo–twofold rotational symmetry, with a dihedral angle between the naphthalene groups of 55.30 (8)°. The torsion angle C4—C3—C3'—C4' about the C—C bridge is -63.8 (2)°. In each segment, the two phenyl rings have different conformational orientations, with inter-ring dihedral angles of 34.7 (2) and 49.63 (16)°. Each cyclopentane ring has the same relative configuration in its four chiral centres [C2(S, C3(S, C4(S, C5(R and C2'(S, C3'(S, C4'(S, C5'(R] and together with the naphthalene ring give an overall chair-like conformation. As expected there are no significant intermolecular interactions, giving simple unassociated molecular stacks (Figs. 2 and 3).

Related literature top

For photoluminescence properties of naphthalene compounds, see: Cai et al. (2010); Haneline et al. (2002); Koning et al. (2003); Tsubaki et al. (2006). For a related structure, see: Dyker (1993);

Experimental top

The title compound was prepared by a coupling reaction with 2,5-diphenyl-3-hydroxyl-3,4-naphthocyclopentan-1-one. This ketone (0.38 g, 1 mmol) and Me₃SiCl (0.61 g, 6 mmol) were dissolved in 10 ml of dry toluene and a suspension of 0.9 g (6 mmol) of NaI in 1 ml of anhydrous CH₃CN was added. The system was stirred at room temperature with light-avoidance for 8 h. When the reactant was exhausted, the reaction was cooled to 273 K and quenched with 10 ml of water. The mixture was extracted with diethyl ether, and the organic fraction was washed with aqueous sodium thiosulfate and brine in sequence, and evaporated under reduced pressure to give the crude product which was purified by flash chromatography (eluent: dichloromethane/petroleum ether, 1:5) to give title compound (0.23 g). Colorless crystals were obtained from a dichloromethane solution layered with methanol after a few days.

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular conformation and atom numbering scheme for the title compound, showing 30% probability displacement ellipsoids.
	Fig. 2. The stacking mode of the title compound.
	Fig. 3. A view of the molecular stacks of the title compound extending along the c axis.

rac-7,7',9,9'-Tetraphenyl-9a,9a'-bi(7,8,9,9a-tetrahydro-6aH- pentaleno[1,2,3-ij]naphthalen-8-one) top

Crystal data top

C₅₄H₃₈O₂	F(000) = 1512
M_r = 718.84	D_x = 1.270 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 42062 reflections
a = 14.325 (3) Å	θ = 2.6–27.7°
b = 13.448 (3) Å	µ = 0.08 mm⁻¹
c = 19.914 (4) Å	T = 275 K
β = 101.449 (5)°	Block, colorless
V = 3759.9 (14) Å³	0.23 × 0.22 × 0.19 mm
Z = 4

Data collection top

Bruker CCD area-detector diffractometer	8342 independent reflections
Radiation source: fine-focus sealed tube	4812 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.051
ϕ and ω scans	θ_max = 27.7°, θ_min = 2.6°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −18→18
T_min = 0.983, T_max = 0.986	k = −15→17
42062 measured reflections	l = −25→22

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)] = 0.066	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.161	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0377P)² + 2.9173P] where P = (F_o² + 2F_c²)/3
8342 reflections	(Δ/σ)_max < 0.001
505 parameters	Δρ_max = 0.21 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³

Crystal data top

C₅₄H₃₈O₂	V = 3759.9 (14) Å³
M_r = 718.84	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 14.325 (3) Å	µ = 0.08 mm⁻¹
b = 13.448 (3) Å	T = 275 K
c = 19.914 (4) Å	0.23 × 0.22 × 0.19 mm
β = 101.449 (5)°

Data collection top

Bruker CCD area-detector diffractometer	8342 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	4812 reflections with I > 2σ(I)
T_min = 0.983, T_max = 0.986	R_int = 0.051
42062 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.066	0 restraints
wR(F²) = 0.161	H-atom parameters constrained
S = 1.05	Δρ_max = 0.21 e Å⁻³
8342 reflections	Δρ_min = −0.20 e Å⁻³
505 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
O1	0.44413 (13)	0.31609 (14)	0.25183 (10)	0.0548 (5)
O1'	0.14712 (15)	0.08762 (17)	−0.05330 (12)	0.0808 (7)
C1	0.36038 (18)	0.30516 (18)	0.22892 (12)	0.0412 (6)
C1'	0.16606 (19)	0.1682 (2)	−0.02781 (15)	0.0553 (7)
C2	0.31861 (17)	0.22012 (18)	0.18147 (12)	0.0424 (6)
H2	0.3620	0.2062	0.1503	0.051*
C2'	0.25646 (18)	0.18987 (19)	0.02529 (13)	0.0458 (6)
H2'	0.2660	0.1355	0.0587	0.055*
C3	0.22333 (16)	0.26340 (18)	0.13837 (12)	0.0388 (6)
C3'	0.23484 (17)	0.28710 (18)	0.06285 (12)	0.0402 (6)
C4	0.20277 (17)	0.36262 (18)	0.17678 (12)	0.0400 (6)
H4	0.2057	0.4205	0.1474	0.048*
C4'	0.13773 (18)	0.32998 (19)	0.01889 (12)	0.0444 (6)
H4'	0.0882	0.3299	0.0465	0.053*
C5	0.28023 (17)	0.37074 (18)	0.24304 (12)	0.0408 (6)
H5	0.2544	0.3381	0.2794	0.049*
C5'	0.10759 (19)	0.2619 (2)	−0.04458 (14)	0.0549 (7)
H5'	0.1307	0.2942	−0.0823	0.066*
C6	0.31185 (18)	0.12745 (18)	0.22407 (13)	0.0423 (6)
C6'	0.34115 (18)	0.1922 (2)	−0.00976 (13)	0.0463 (6)
C7	0.3683 (2)	0.0463 (2)	0.21658 (16)	0.0584 (7)
H7	0.4090	0.0493	0.1856	0.070*
C7'	0.4174 (2)	0.1298 (2)	0.01212 (16)	0.0647 (8)
H7'	0.4168	0.0868	0.0486	0.078*
C8	0.3647 (2)	−0.0398 (2)	0.2549 (2)	0.0776 (10)
H8	0.4020	−0.0944	0.2488	0.093*
C8'	0.4955 (2)	0.1306 (3)	−0.0199 (2)	0.0807 (10)
H8'	0.5467	0.0884	−0.0044	0.097*
C9	0.3061 (2)	−0.0439 (3)	0.30166 (19)	0.0764 (10)
H9	0.3040	−0.1013	0.3274	0.092*
C9'	0.4979 (2)	0.1925 (3)	−0.0738 (2)	0.0768 (10)
H9'	0.5499	0.1921	−0.0953	0.092*
C10	0.2513 (2)	0.0357 (2)	0.31033 (15)	0.0602 (8)
H10	0.2119	0.0328	0.3422	0.072*
C10'	0.4226 (2)	0.2553 (3)	−0.09590 (15)	0.0642 (8)
H10'	0.4237	0.2982	−0.1323	0.077*
C11	0.2539 (2)	0.1205 (2)	0.27215 (13)	0.0510 (7)
H11	0.2160	0.1744	0.2787	0.061*
C11'	0.3453 (2)	0.2549 (2)	−0.06445 (13)	0.0549 (7)
H11'	0.2947	0.2977	−0.0802	0.066*
C12	0.13540 (17)	0.19949 (19)	0.13976 (12)	0.0431 (6)
C12'	0.30568 (18)	0.37184 (19)	0.06057 (12)	0.0428 (6)
C13	0.1127 (2)	0.1028 (2)	0.12165 (15)	0.0569 (7)
H13	0.1555	0.0628	0.1045	0.068*
C13'	0.40160 (19)	0.3802 (2)	0.08404 (13)	0.0501 (7)
H13'	0.4362	0.3274	0.1067	0.060*
C14	0.0239 (2)	0.0648 (3)	0.12933 (17)	0.0703 (9)
H14	0.0086	−0.0004	0.1160	0.084*
C14'	0.4475 (2)	0.4701 (2)	0.07354 (15)	0.0624 (8)
H14'	0.5128	0.4754	0.0896	0.075*
C15	−0.0401 (2)	0.1193 (3)	0.15528 (16)	0.0685 (9)
H15	−0.0984	0.0915	0.1587	0.082*
C15'	0.3997 (2)	0.5494 (2)	0.04072 (16)	0.0661 (9)
H15'	0.4323	0.6077	0.0354	0.079*
C16	−0.0753 (2)	0.2827 (3)	0.20793 (16)	0.0697 (9)
H16	−0.1352	0.2624	0.2138	0.084*
C16'	0.2416 (3)	0.6173 (2)	−0.02160 (16)	0.0712 (9)
H16'	0.2672	0.6786	−0.0299	0.085*
C17	−0.0424 (2)	0.3745 (3)	0.22916 (16)	0.0728 (10)
H17	−0.0803	0.4154	0.2503	0.087*
C17'	0.1474 (3)	0.5996 (2)	−0.04458 (16)	0.0733 (10)
H17'	0.1098	0.6497	−0.0681	0.088*
C18	0.0470 (2)	0.4105 (2)	0.22040 (14)	0.0599 (8)
H18	0.0673	0.4739	0.2351	0.072*
C18'	0.1045 (2)	0.5084 (2)	−0.03424 (14)	0.0624 (8)
H18'	0.0400	0.4979	−0.0512	0.075*
C19	0.10300 (17)	0.3502 (2)	0.18994 (13)	0.0453 (6)
C19'	0.15998 (19)	0.4353 (2)	0.00136 (12)	0.0477 (6)
C20	−0.01890 (19)	0.2181 (2)	0.17719 (14)	0.0567 (8)
C20'	0.3014 (2)	0.5432 (2)	0.01489 (14)	0.0567 (7)
C21	0.07006 (17)	0.2551 (2)	0.16821 (13)	0.0451 (6)
C21'	0.25666 (19)	0.45336 (19)	0.02589 (12)	0.0444 (6)
C22	0.30952 (17)	0.47445 (19)	0.26837 (13)	0.0458 (6)
C22'	0.0013 (2)	0.2486 (3)	−0.06871 (15)	0.0640 (8)
C23	0.3551 (2)	0.5379 (2)	0.23124 (17)	0.0648 (8)
H23	0.3667	0.5175	0.1891	0.078*
C23'	−0.0474 (3)	0.3071 (3)	−0.12167 (17)	0.0907 (12)
H23'	−0.0141	0.3523	−0.1433	0.109*
C24	0.3837 (2)	0.6309 (2)	0.2554 (2)	0.0819 (11)
H24	0.4149	0.6724	0.2296	0.098*
C24'	−0.1452 (3)	0.2986 (5)	−0.1425 (2)	0.1201 (19)
H24'	−0.1773	0.3395	−0.1772	0.144*
C25	0.3669 (3)	0.6630 (3)	0.3166 (3)	0.0902 (13)
H25	0.3866	0.7260	0.3327	0.108*
C25'	−0.1948 (3)	0.2307 (5)	−0.1127 (3)	0.122 (2)
H25'	−0.2602	0.2243	−0.1278	0.147*
C26	0.3203 (3)	0.6012 (3)	0.3549 (2)	0.0913 (12)
H26	0.3081	0.6227	0.3967	0.110*
C26'	−0.1475 (3)	0.1711 (4)	−0.0598 (3)	0.1068 (15)
H26'	−0.1808	0.1246	−0.0392	0.128*
C27	0.2920 (2)	0.5070 (2)	0.33056 (15)	0.0643 (8)
H27	0.2609	0.4654	0.3563	0.077*
C27'	−0.0500 (2)	0.1820 (3)	−0.0381 (2)	0.0796 (10)
H27'	−0.0185	0.1433	−0.0019	0.095*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0416 (11)	0.0534 (12)	0.0663 (12)	−0.0047 (9)	0.0033 (9)	0.0017 (10)
O1'	0.0679 (14)	0.0671 (15)	0.1050 (18)	−0.0086 (12)	0.0112 (12)	−0.0422 (14)
C1	0.0422 (15)	0.0393 (14)	0.0415 (13)	−0.0041 (11)	0.0070 (11)	0.0061 (11)
C1'	0.0504 (16)	0.0584 (19)	0.0589 (17)	−0.0060 (14)	0.0153 (13)	−0.0190 (15)
C2	0.0439 (14)	0.0398 (14)	0.0457 (14)	−0.0009 (12)	0.0139 (11)	−0.0013 (12)
C2'	0.0501 (15)	0.0422 (15)	0.0458 (14)	0.0008 (12)	0.0113 (12)	−0.0050 (12)
C3	0.0388 (13)	0.0362 (13)	0.0424 (13)	−0.0013 (11)	0.0103 (10)	−0.0029 (11)
C3'	0.0422 (14)	0.0370 (13)	0.0418 (13)	−0.0014 (11)	0.0093 (11)	−0.0041 (11)
C4	0.0438 (14)	0.0372 (14)	0.0391 (13)	0.0001 (11)	0.0085 (10)	−0.0005 (11)
C4'	0.0438 (14)	0.0475 (15)	0.0417 (13)	0.0018 (12)	0.0077 (11)	−0.0050 (12)
C5	0.0430 (13)	0.0402 (14)	0.0404 (13)	−0.0050 (11)	0.0113 (11)	−0.0011 (11)
C5'	0.0537 (16)	0.0622 (19)	0.0471 (15)	−0.0011 (14)	0.0054 (12)	−0.0112 (14)
C6	0.0451 (14)	0.0334 (13)	0.0458 (14)	−0.0012 (11)	0.0025 (11)	−0.0004 (11)
C6'	0.0472 (15)	0.0460 (15)	0.0459 (14)	0.0026 (12)	0.0100 (12)	−0.0120 (13)
C7	0.0517 (17)	0.0484 (17)	0.075 (2)	0.0056 (14)	0.0110 (14)	0.0065 (15)
C7'	0.0641 (19)	0.0612 (19)	0.071 (2)	0.0147 (16)	0.0173 (16)	−0.0021 (16)
C8	0.070 (2)	0.0497 (19)	0.112 (3)	0.0177 (17)	0.014 (2)	0.018 (2)
C8'	0.062 (2)	0.077 (2)	0.105 (3)	0.0181 (19)	0.023 (2)	−0.007 (2)
C9	0.074 (2)	0.055 (2)	0.097 (3)	−0.0004 (18)	0.009 (2)	0.0269 (19)
C9'	0.061 (2)	0.085 (3)	0.091 (3)	−0.0031 (19)	0.0328 (19)	−0.018 (2)
C10	0.0663 (19)	0.0526 (18)	0.0603 (18)	−0.0105 (16)	0.0094 (15)	0.0125 (15)
C10'	0.0635 (19)	0.077 (2)	0.0558 (17)	−0.0107 (18)	0.0203 (15)	−0.0122 (16)
C11	0.0588 (17)	0.0430 (15)	0.0518 (16)	−0.0023 (13)	0.0121 (13)	0.0050 (13)
C11'	0.0514 (16)	0.0658 (19)	0.0474 (15)	0.0002 (14)	0.0095 (13)	−0.0074 (14)
C12	0.0431 (14)	0.0419 (14)	0.0442 (14)	−0.0050 (12)	0.0083 (11)	0.0044 (12)
C12'	0.0473 (15)	0.0423 (15)	0.0406 (13)	−0.0064 (12)	0.0131 (11)	−0.0057 (12)
C13	0.0577 (17)	0.0462 (17)	0.0664 (18)	−0.0127 (14)	0.0116 (14)	−0.0028 (14)
C13'	0.0538 (16)	0.0534 (17)	0.0460 (15)	−0.0045 (14)	0.0167 (12)	−0.0005 (13)
C14	0.065 (2)	0.061 (2)	0.081 (2)	−0.0229 (17)	0.0041 (17)	0.0055 (18)
C14'	0.0587 (18)	0.069 (2)	0.0630 (18)	−0.0216 (16)	0.0197 (15)	−0.0025 (17)
C15	0.0510 (18)	0.077 (2)	0.075 (2)	−0.0225 (17)	0.0071 (16)	0.0205 (19)
C15'	0.089 (2)	0.0524 (19)	0.0639 (19)	−0.0241 (18)	0.0311 (17)	−0.0038 (16)
C16	0.0465 (17)	0.103 (3)	0.0613 (19)	−0.0004 (19)	0.0151 (15)	0.013 (2)
C16'	0.115 (3)	0.0438 (18)	0.0616 (19)	−0.0006 (19)	0.033 (2)	0.0073 (16)
C17	0.0518 (18)	0.107 (3)	0.063 (2)	0.019 (2)	0.0195 (15)	−0.002 (2)
C17'	0.109 (3)	0.054 (2)	0.0602 (19)	0.021 (2)	0.0232 (19)	0.0123 (16)
C18	0.0530 (17)	0.070 (2)	0.0572 (17)	0.0113 (15)	0.0114 (14)	−0.0083 (15)
C18'	0.076 (2)	0.063 (2)	0.0487 (16)	0.0175 (17)	0.0138 (15)	0.0059 (15)
C19	0.0390 (14)	0.0543 (17)	0.0427 (14)	0.0057 (12)	0.0086 (11)	0.0020 (12)
C19'	0.0604 (17)	0.0467 (16)	0.0372 (13)	0.0046 (13)	0.0131 (12)	−0.0011 (12)
C20	0.0436 (15)	0.074 (2)	0.0522 (16)	−0.0029 (15)	0.0086 (13)	0.0191 (15)
C20'	0.084 (2)	0.0453 (17)	0.0466 (15)	−0.0068 (16)	0.0260 (15)	−0.0025 (13)
C21	0.0368 (13)	0.0523 (16)	0.0457 (14)	−0.0018 (12)	0.0068 (11)	0.0094 (13)
C21'	0.0596 (17)	0.0410 (15)	0.0359 (13)	−0.0038 (13)	0.0173 (12)	−0.0022 (11)
C22	0.0409 (14)	0.0418 (15)	0.0520 (15)	0.0010 (12)	0.0028 (11)	−0.0026 (13)
C22'	0.0517 (17)	0.080 (2)	0.0557 (18)	0.0043 (17)	−0.0005 (14)	−0.0268 (17)
C23	0.069 (2)	0.0473 (17)	0.080 (2)	−0.0124 (15)	0.0178 (17)	−0.0042 (16)
C23'	0.075 (2)	0.133 (4)	0.057 (2)	0.021 (2)	−0.0047 (18)	−0.013 (2)
C24	0.069 (2)	0.0457 (19)	0.126 (3)	−0.0097 (17)	0.006 (2)	0.000 (2)
C24'	0.071 (3)	0.192 (6)	0.082 (3)	0.038 (3)	−0.021 (2)	−0.039 (3)
C25	0.078 (3)	0.044 (2)	0.132 (4)	0.0008 (18)	−0.019 (2)	−0.028 (2)
C25'	0.053 (3)	0.178 (6)	0.128 (4)	0.009 (3)	−0.002 (3)	−0.079 (4)
C26	0.106 (3)	0.074 (3)	0.083 (3)	0.015 (2)	−0.007 (2)	−0.040 (2)
C26'	0.059 (2)	0.115 (4)	0.148 (4)	−0.011 (2)	0.022 (3)	−0.057 (3)
C27	0.073 (2)	0.061 (2)	0.0580 (18)	0.0023 (16)	0.0109 (15)	−0.0106 (16)
C27'	0.055 (2)	0.087 (3)	0.095 (3)	−0.0116 (19)	0.0107 (18)	−0.028 (2)

Geometric parameters (Å, º) top

O1—C1	1.205 (3)	C13—C14	1.407 (4)
O1'—C1'	1.204 (3)	C13—H13	0.9300
C1—C5	1.518 (3)	C13'—C14'	1.412 (4)
C1—C2	1.528 (3)	C13'—H13'	0.9300
C1'—C5'	1.514 (4)	C14—C15	1.354 (4)
C1'—C2'	1.529 (4)	C14—H14	0.9300
C2—C6	1.521 (3)	C14'—C15'	1.362 (4)
C2—C3	1.573 (3)	C14'—H14'	0.9300
C2—H2	0.9800	C15—C20	1.413 (4)
C2'—C6'	1.515 (3)	C15—H15	0.9300
C2'—C3'	1.567 (3)	C15'—C20'	1.402 (4)
C2'—H2'	0.9800	C15'—H15'	0.9300
C3—C12	1.530 (3)	C16—C17	1.360 (5)
C3—C3'	1.578 (3)	C16—C20	1.405 (4)
C3—C4	1.594 (3)	C16—H16	0.9300
C3'—C12'	1.533 (3)	C16'—C17'	1.358 (5)
C3'—C4'	1.597 (3)	C16'—C20'	1.416 (4)
C4—C19	1.512 (3)	C16'—H16'	0.9300
C4—C5	1.550 (3)	C17—C18	1.412 (4)
C4—H4	0.9800	C17—H17	0.9300
C4'—C19'	1.508 (4)	C17'—C18'	1.405 (5)
C4'—C5'	1.551 (3)	C17'—H17'	0.9300
C4'—H4'	0.9800	C18—C19	1.364 (4)
C5—C22	1.514 (3)	C18—H18	0.9300
C5—H5	0.9800	C18'—C19'	1.370 (4)
C5'—C22'	1.514 (4)	C18'—H18'	0.9300
C5'—H5'	0.9800	C19—C21	1.402 (4)
C6—C7	1.383 (4)	C19'—C21'	1.395 (4)
C6—C11	1.389 (4)	C20—C21	1.412 (4)
C6'—C7'	1.378 (4)	C20'—C21'	1.406 (4)
C6'—C11'	1.388 (4)	C22—C23	1.376 (4)
C7—C8	1.394 (4)	C22—C27	1.383 (4)
C7—H7	0.9300	C22'—C27'	1.375 (5)
C7'—C8'	1.394 (4)	C22'—C23'	1.388 (5)
C7'—H7'	0.9300	C23—C24	1.373 (4)
C8—C9	1.373 (5)	C23—H23	0.9300
C8—H8	0.9300	C23'—C24'	1.385 (5)
C8'—C9'	1.363 (5)	C23'—H23'	0.9300
C8'—H8'	0.9300	C24—C25	1.358 (5)
C9—C10	1.359 (4)	C24—H24	0.9300
C9—H9	0.9300	C24'—C25'	1.363 (7)
C9'—C10'	1.372 (5)	C24'—H24'	0.9300
C9'—H9'	0.9300	C25—C26	1.387 (5)
C10—C11	1.375 (4)	C25—H25	0.9300
C10—H10	0.9300	C25'—C26'	1.388 (7)
C10'—C11'	1.375 (4)	C25'—H25'	0.9300
C10'—H10'	0.9300	C26—C27	1.388 (5)
C11—H11	0.9300	C26—H26	0.9300
C11'—H11'	0.9300	C26'—C27'	1.385 (5)
C12—C13	1.371 (4)	C26'—H26'	0.9300
C12—C21	1.402 (3)	C27—H27	0.9300
C12'—C13'	1.365 (3)	C27'—H27'	0.9300
C12'—C21'	1.407 (3)

O1—C1—C5	126.3 (2)	C13'—C12'—C21'	118.3 (2)
O1—C1—C2	124.3 (2)	C13'—C12'—C3'	132.7 (2)
C5—C1—C2	109.4 (2)	C21'—C12'—C3'	109.0 (2)
O1'—C1'—C5'	126.0 (3)	C12—C13—C14	119.2 (3)
O1'—C1'—C2'	123.5 (3)	C12—C13—H13	120.4
C5'—C1'—C2'	110.4 (2)	C14—C13—H13	120.4
C6—C2—C1	109.19 (19)	C12'—C13'—C14'	119.1 (3)
C6—C2—C3	117.6 (2)	C12'—C13'—H13'	120.4
C1—C2—C3	104.56 (19)	C14'—C13'—H13'	120.4
C6—C2—H2	108.4	C15—C14—C13	122.8 (3)
C1—C2—H2	108.4	C15—C14—H14	118.6
C3—C2—H2	108.4	C13—C14—H14	118.6
C6'—C2'—C1'	109.3 (2)	C15'—C14'—C13'	122.5 (3)
C6'—C2'—C3'	117.0 (2)	C15'—C14'—H14'	118.8
C1'—C2'—C3'	105.6 (2)	C13'—C14'—H14'	118.8
C6'—C2'—H2'	108.2	C14—C15—C20	120.4 (3)
C1'—C2'—H2'	108.2	C14—C15—H15	119.8
C3'—C2'—H2'	108.2	C20—C15—H15	119.8
C12—C3—C2	114.3 (2)	C14'—C15'—C20'	120.1 (3)
C12—C3—C3'	111.90 (19)	C14'—C15'—H15'	119.9
C2—C3—C3'	110.57 (18)	C20'—C15'—H15'	119.9
C12—C3—C4	103.32 (18)	C17—C16—C20	120.2 (3)
C2—C3—C4	105.72 (18)	C17—C16—H16	119.9
C3'—C3—C4	110.64 (19)	C20—C16—H16	119.9
C12'—C3'—C2'	114.3 (2)	C17'—C16'—C20'	120.6 (3)
C12'—C3'—C3	111.93 (19)	C17'—C16'—H16'	119.7
C2'—C3'—C3	110.7 (2)	C20'—C16'—H16'	119.7
C12'—C3'—C4'	103.0 (2)	C16—C17—C18	122.6 (3)
C2'—C3'—C4'	105.83 (19)	C16—C17—H17	118.7
C3—C3'—C4'	110.55 (19)	C18—C17—H17	118.7
C19—C4—C5	113.7 (2)	C16'—C17'—C18'	122.6 (3)
C19—C4—C3	105.17 (19)	C16'—C17'—H17'	118.7
C5—C4—C3	107.35 (19)	C18'—C17'—H17'	118.7
C19—C4—H4	110.2	C19—C18—C17	118.7 (3)
C5—C4—H4	110.2	C19—C18—H18	120.7
C3—C4—H4	110.2	C17—C18—H18	120.7
C19'—C4'—C5'	113.8 (2)	C19'—C18'—C17'	118.5 (3)
C19'—C4'—C3'	105.4 (2)	C19'—C18'—H18'	120.8
C5'—C4'—C3'	107.8 (2)	C17'—C18'—H18'	120.8
C19'—C4'—H4'	109.9	C18—C19—C21	119.2 (2)
C5'—C4'—H4'	109.9	C18—C19—C4	132.1 (3)
C3'—C4'—H4'	109.9	C21—C19—C4	108.6 (2)
C22—C5—C1	115.3 (2)	C18'—C19'—C21'	119.3 (3)
C22—C5—C4	116.9 (2)	C18'—C19'—C4'	131.8 (3)
C1—C5—C4	103.97 (19)	C21'—C19'—C4'	108.9 (2)
C22—C5—H5	106.7	C16—C20—C21	116.7 (3)
C1—C5—H5	106.7	C16—C20—C15	127.5 (3)
C4—C5—H5	106.7	C21—C20—C15	115.9 (3)
C1'—C5'—C22'	116.7 (3)	C15'—C20'—C21'	116.7 (3)
C1'—C5'—C4'	105.0 (2)	C15'—C20'—C16'	127.4 (3)
C22'—C5'—C4'	115.4 (2)	C21'—C20'—C16'	115.9 (3)
C1'—C5'—H5'	106.3	C19—C21—C12	113.6 (2)
C22'—C5'—H5'	106.3	C19—C21—C20	122.6 (3)
C4'—C5'—H5'	106.3	C12—C21—C20	123.7 (3)
C7—C6—C11	117.6 (2)	C19'—C21'—C20'	123.2 (3)
C7—C6—C2	118.8 (2)	C19'—C21'—C12'	113.6 (2)
C11—C6—C2	123.5 (2)	C20'—C21'—C12'	123.2 (3)
C7'—C6'—C11'	117.6 (3)	C23—C22—C27	118.4 (3)
C7'—C6'—C2'	119.9 (3)	C23—C22—C5	121.5 (2)
C11'—C6'—C2'	122.5 (2)	C27—C22—C5	120.2 (2)
C6—C7—C8	120.7 (3)	C27'—C22'—C23'	118.3 (3)
C6—C7—H7	119.7	C27'—C22'—C5'	121.9 (3)
C8—C7—H7	119.7	C23'—C22'—C5'	119.7 (3)
C6'—C7'—C8'	120.6 (3)	C24—C23—C22	121.2 (3)
C6'—C7'—H7'	119.7	C24—C23—H23	119.4
C8'—C7'—H7'	119.7	C22—C23—H23	119.4
C9—C8—C7	119.9 (3)	C24'—C23'—C22'	120.5 (4)
C9—C8—H8	120.0	C24'—C23'—H23'	119.8
C7—C8—H8	120.0	C22'—C23'—H23'	119.8
C9'—C8'—C7'	120.9 (3)	C25—C24—C23	120.6 (4)
C9'—C8'—H8'	119.6	C25—C24—H24	119.7
C7'—C8'—H8'	119.6	C23—C24—H24	119.7
C10—C9—C8	120.1 (3)	C25'—C24'—C23'	120.5 (5)
C10—C9—H9	120.0	C25'—C24'—H24'	119.7
C8—C9—H9	120.0	C23'—C24'—H24'	119.7
C8'—C9'—C10'	119.1 (3)	C24—C25—C26	119.6 (3)
C8'—C9'—H9'	120.4	C24—C25—H25	120.2
C10'—C9'—H9'	120.4	C26—C25—H25	120.2
C9—C10—C11	120.2 (3)	C24'—C25'—C26'	120.0 (4)
C9—C10—H10	119.9	C24'—C25'—H25'	120.0
C11—C10—H10	119.9	C26'—C25'—H25'	120.0
C9'—C10'—C11'	120.3 (3)	C25—C26—C27	119.6 (4)
C9'—C10'—H10'	119.9	C25—C26—H26	120.2
C11'—C10'—H10'	119.9	C27—C26—H26	120.2
C10—C11—C6	121.5 (3)	C27'—C26'—C25'	119.1 (5)
C10—C11—H11	119.3	C27'—C26'—H26'	120.5
C6—C11—H11	119.3	C25'—C26'—H26'	120.5
C10'—C11'—C6'	121.6 (3)	C22—C27—C26	120.6 (3)
C10'—C11'—H11'	119.2	C22—C27—H27	119.7
C6'—C11'—H11'	119.2	C26—C27—H27	119.7
C13—C12—C21	118.0 (2)	C22'—C27'—C26'	121.6 (4)
C13—C12—C3	132.9 (2)	C22'—C27'—H27'	119.2
C21—C12—C3	109.0 (2)	C26'—C27'—H27'	119.2

O1—C1—C2—C6	80.6 (3)	C2'—C3'—C12'—C13'	−60.7 (4)
C5—C1—C2—C6	−98.4 (2)	C3—C3'—C12'—C13'	66.2 (3)
O1—C1—C2—C3	−152.8 (2)	C4'—C3'—C12'—C13'	−175.0 (3)
C5—C1—C2—C3	28.3 (2)	C2'—C3'—C12'—C21'	118.3 (2)
O1'—C1'—C2'—C6'	73.5 (4)	C3—C3'—C12'—C21'	−114.8 (2)
C5'—C1'—C2'—C6'	−104.6 (3)	C4'—C3'—C12'—C21'	4.0 (2)
O1'—C1'—C2'—C3'	−159.8 (3)	C21—C12—C13—C14	2.8 (4)
C5'—C1'—C2'—C3'	22.1 (3)	C3—C12—C13—C14	179.9 (3)
C6—C2—C3—C12	−5.6 (3)	C21'—C12'—C13'—C14'	0.8 (4)
C1—C2—C3—C12	−126.8 (2)	C3'—C12'—C13'—C14'	179.8 (2)
C6—C2—C3—C3'	−132.9 (2)	C12—C13—C14—C15	−1.3 (5)
C1—C2—C3—C3'	105.9 (2)	C12'—C13'—C14'—C15'	0.0 (4)
C6—C2—C3—C4	107.3 (2)	C13—C14—C15—C20	−1.1 (5)
C1—C2—C3—C4	−13.9 (2)	C13'—C14'—C15'—C20'	−1.0 (5)
C6'—C2'—C3'—C12'	−1.7 (3)	C20—C16—C17—C18	1.4 (5)
C1'—C2'—C3'—C12'	−123.6 (2)	C20'—C16'—C17'—C18'	−0.5 (5)
C6'—C2'—C3'—C3	−129.3 (2)	C16—C17—C18—C19	−0.6 (5)
C1'—C2'—C3'—C3	108.9 (2)	C16'—C17'—C18'—C19'	1.0 (5)
C6'—C2'—C3'—C4'	110.9 (2)	C17—C18—C19—C21	0.2 (4)
C1'—C2'—C3'—C4'	−11.0 (3)	C17—C18—C19—C4	−175.8 (3)
C12—C3—C3'—C12'	165.0 (2)	C5—C4—C19—C18	63.3 (4)
C2—C3—C3'—C12'	−66.4 (2)	C3—C4—C19—C18	−179.5 (3)
C4—C3—C3'—C12'	50.4 (3)	C5—C4—C19—C21	−113.0 (2)
C12—C3—C3'—C2'	−66.2 (2)	C3—C4—C19—C21	4.2 (3)
C2—C3—C3'—C2'	62.4 (2)	C17'—C18'—C19'—C21'	−0.2 (4)
C4—C3—C3'—C2'	179.22 (19)	C17'—C18'—C19'—C4'	−177.5 (3)
C12—C3—C3'—C4'	50.8 (3)	C5'—C4'—C19'—C18'	63.4 (4)
C2—C3—C3'—C4'	179.41 (19)	C3'—C4'—C19'—C18'	−178.8 (3)
C4—C3—C3'—C4'	−63.8 (2)	C5'—C4'—C19'—C21'	−114.1 (2)
C12—C3—C4—C19	−5.3 (2)	C3'—C4'—C19'—C21'	3.7 (3)
C2—C3—C4—C19	−125.6 (2)	C17—C16—C20—C21	−1.8 (4)
C3'—C3—C4—C19	114.6 (2)	C17—C16—C20—C15	176.8 (3)
C12—C3—C4—C5	116.1 (2)	C14—C15—C20—C16	−176.9 (3)
C2—C3—C4—C5	−4.3 (2)	C14—C15—C20—C21	1.8 (4)
C3'—C3—C4—C5	−124.0 (2)	C14'—C15'—C20'—C21'	1.1 (4)
C12'—C3'—C4'—C19'	−4.5 (2)	C14'—C15'—C20'—C16'	−178.5 (3)
C2'—C3'—C4'—C19'	−124.8 (2)	C17'—C16'—C20'—C15'	178.8 (3)
C3—C3'—C4'—C19'	115.2 (2)	C17'—C16'—C20'—C21'	−0.8 (4)
C12'—C3'—C4'—C5'	117.2 (2)	C18—C19—C21—C12	−178.1 (2)
C2'—C3'—C4'—C5'	−3.0 (3)	C4—C19—C21—C12	−1.2 (3)
C3—C3'—C4'—C5'	−123.0 (2)	C18—C19—C21—C20	−0.7 (4)
O1—C1—C5—C22	20.9 (4)	C4—C19—C21—C20	176.2 (2)
C2—C1—C5—C22	−160.2 (2)	C13—C12—C21—C19	175.2 (2)
O1—C1—C5—C4	150.2 (2)	C3—C12—C21—C19	−2.5 (3)
C2—C1—C5—C4	−30.9 (2)	C13—C12—C21—C20	−2.1 (4)
C19—C4—C5—C22	−95.0 (3)	C3—C12—C21—C20	−179.8 (2)
C3—C4—C5—C22	149.1 (2)	C16—C20—C21—C19	1.5 (4)
C19—C4—C5—C1	136.7 (2)	C15—C20—C21—C19	−177.3 (2)
C3—C4—C5—C1	20.8 (2)	C16—C20—C21—C12	178.6 (2)
O1'—C1'—C5'—C22'	29.0 (4)	C15—C20—C21—C12	−0.2 (4)
C2'—C1'—C5'—C22'	−153.0 (2)	C18'—C19'—C21'—C20'	−1.2 (4)
O1'—C1'—C5'—C4'	158.1 (3)	C4'—C19'—C21'—C20'	176.7 (2)
C2'—C1'—C5'—C4'	−23.9 (3)	C18'—C19'—C21'—C12'	−179.1 (2)
C19'—C4'—C5'—C1'	132.4 (2)	C4'—C19'—C21'—C12'	−1.2 (3)
C3'—C4'—C5'—C1'	16.0 (3)	C15'—C20'—C21'—C19'	−178.0 (2)
C19'—C4'—C5'—C22'	−97.7 (3)	C16'—C20'—C21'—C19'	1.7 (4)
C3'—C4'—C5'—C22'	145.9 (3)	C15'—C20'—C21'—C12'	−0.3 (4)
C1—C2—C6—C7	−113.7 (3)	C16'—C20'—C21'—C12'	179.4 (2)
C3—C2—C6—C7	127.4 (3)	C13'—C12'—C21'—C19'	177.2 (2)
C1—C2—C6—C11	64.2 (3)	C3'—C12'—C21'—C19'	−2.0 (3)
C3—C2—C6—C11	−54.7 (3)	C13'—C12'—C21'—C20'	−0.7 (4)
C1'—C2'—C6'—C7'	−123.1 (3)	C3'—C12'—C21'—C20'	−179.8 (2)
C3'—C2'—C6'—C7'	117.0 (3)	C1—C5—C22—C23	57.1 (3)
C1'—C2'—C6'—C11'	56.2 (3)	C4—C5—C22—C23	−65.6 (3)
C3'—C2'—C6'—C11'	−63.7 (3)	C1—C5—C22—C27	−122.0 (3)
C11—C6—C7—C8	1.6 (4)	C4—C5—C22—C27	115.4 (3)
C2—C6—C7—C8	179.6 (3)	C1'—C5'—C22'—C27'	42.8 (4)
C11'—C6'—C7'—C8'	0.1 (4)	C4'—C5'—C22'—C27'	−81.2 (4)
C2'—C6'—C7'—C8'	179.5 (3)	C1'—C5'—C22'—C23'	−139.5 (3)
C6—C7—C8—C9	−1.3 (5)	C4'—C5'—C22'—C23'	96.5 (3)
C6'—C7'—C8'—C9'	−0.5 (5)	C27—C22—C23—C24	0.8 (4)
C7—C8—C9—C10	0.3 (5)	C5—C22—C23—C24	−178.3 (3)
C7'—C8'—C9'—C10'	0.7 (5)	C27'—C22'—C23'—C24'	0.4 (5)
C8—C9—C10—C11	0.3 (5)	C5'—C22'—C23'—C24'	−177.4 (3)
C8'—C9'—C10'—C11'	−0.7 (5)	C22—C23—C24—C25	−0.6 (5)
C9—C10—C11—C6	0.1 (4)	C22'—C23'—C24'—C25'	−1.9 (6)
C7—C6—C11—C10	−1.0 (4)	C23—C24—C25—C26	−0.1 (6)
C2—C6—C11—C10	−178.9 (2)	C23'—C24'—C25'—C26'	1.6 (7)
C9'—C10'—C11'—C6'	0.3 (4)	C24—C25—C26—C27	0.5 (6)
C7'—C6'—C11'—C10'	−0.1 (4)	C24'—C25'—C26'—C27'	0.1 (7)
C2'—C6'—C11'—C10'	−179.4 (2)	C23—C22—C27—C26	−0.4 (4)
C2—C3—C12—C13	−58.1 (4)	C5—C22—C27—C26	178.7 (3)
C3'—C3—C12—C13	68.5 (4)	C25—C26—C27—C22	−0.2 (5)
C4—C3—C12—C13	−172.4 (3)	C23'—C22'—C27'—C26'	1.3 (5)
C2—C3—C12—C21	119.1 (2)	C5'—C22'—C27'—C26'	179.1 (3)
C3'—C3—C12—C21	−114.2 (2)	C25'—C26'—C27'—C22'	−1.6 (6)
C4—C3—C12—C21	4.8 (3)

Experimental details

Crystal data
Chemical formula	C₅₄H₃₈O₂
M_r	718.84
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	275
a, b, c (Å)	14.325 (3), 13.448 (3), 19.914 (4)
β (°)	101.449 (5)
V (Å³)	3759.9 (14)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.23 × 0.22 × 0.19

Data collection
Diffractometer	Bruker CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.983, 0.986
No. of measured, independent and observed [I > 2σ(I)] reflections	42062, 8342, 4812
R_int	0.051
(sin θ/λ)_max (Å⁻¹)	0.654

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.066, 0.161, 1.05
No. of reflections	8342
No. of parameters	505
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.21, −0.20

Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

This work was supported by the National Natural Science Foundation of China (51003009 and 20772014), the Specialized Research Fund for the Doctoral Program of Higher Education (200801411121) and the Fundamental Research Funds for the Central Universities of China (DUT11LK16).

References

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