(3R,3aR,6R,6aR)-Hexa­hydro­furo[3,2-b]furan-3,6-diyl dibenzoate

Piccialli, V.; Zaccaria, S.; Borbone, N.; Centore, R.; Tuzi, A.

doi:10.1107/S1600536813021612

organic compounds

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ISSN: 2056-9890

Volume 69| Part 9| September 2013| Pages o1396-o1397

doi:10.1107/S1600536813021612

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(3R,3aR,6R,6aR)-Hexahydrofuro[3,2-b]furan-3,6-diyl dibenzoate

Vincenzo Piccialli,^a ^* Sabrina Zaccaria,^a Nicola Borbone,^b Roberto Centore ^a and Angela Tuzi ^a ^*

^aDipartimento di Scienze Chimiche, Università degli Studi di Napoli 'Federico II', Complesso di Monte S. Angelo, Via Cinthia, 80126 Napoli, Italy, and ^bDipartimento di Farmacia, Università degli Studi di Napoli 'Federico II', Via D. Montesano 49, 80131 Napoli, Italy
^*Correspondence e-mail: vinpicci@unina.it, angela.tuzi@unina.it

(Received 24 July 2013; accepted 2 August 2013; online 7 August 2013)

The title compound, C₂₀H₁₈O₆, prepared from D-mannitol by a two-step procedure, is a functionalized fused bis-tetrahydrofuran. In the central fragment, consisting of two fused tetrahydrofuran rings, one O atom and its two adjacent C atoms, a methylene and a bridgehead C atom, are disordered over two sets of sites with an occupancy ratio of 0.735 (9):0.265 (9). In the major component, the ring containing the disordered O atom is a half-chair conformation with twisted methylene and benzoate-substituted C atoms, whereas the other ring has a half-chair or T-form conformation. In the minor component, the ring with the disordered O atom has an envelope conformation, with the O atom as the flap, and the other ring has a half-chair conformation, with the O atom and the other bridgehead CH atom being twisted. The two aromatic rings are inclined to one another by 20.00 (12)°. In the crystal, adjacent molecules are linked via C—H⋯π interactions, forming chains propagating along [010].

Related literature

For the use of carbohydrates in the synthesis of complex natural chiral substances, see: Hanessian (1993 ). For mannitol as a chiral reagent and for its biologically active derivatives, see: Babjak et al. (2002 ); Masaki et al. (1999 ); Lohray et al. (1999 ). For oxidative processes mediated by transition of oxo-species, see: Piccialli, Oliviero et al. (2013 ); Piccialli, Tuzi et al. (2013 ); Piccialli, D'Errico et al. (2013 ); Piccialli et al. (2012 ). For the synthesis of the title compound, see: Hockett et al. (1946 ).

Experimental

Crystal data

C₂₀H₁₈O₆
M_r = 354.34
Monoclinic, P 2₁
a = 10.0914 (15) Å
b = 8.2388 (11) Å
c = 10.7592 (10) Å
β = 108.913 (10)°
V = 846.24 (19) Å³
Z = 2
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 173 K
0.50 × 0.20 × 0.10 mm

Data collection

Bruker–Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ) T_min = 0.950, T_max = 0.990
7903 measured reflections
2059 independent reflections
1757 reflections with I > 2σ(I)
R_int = 0.033

Refinement

R[F² > 2σ(F²)] = 0.035
wR(F²) = 0.073
S = 1.11
2059 reflections
263 parameters
12 restraints
H-atom parameters constrained
Δρ_max = 0.14 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C15–C20 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1A⋯Cgⁱ	0.99	2.60	3.419 (3)	149
Symmetry code: (i) x, y+1, z.

Data collection: COLLECT (Nonius, 1999 ); cell refinement: DIRAX/LSQ (Duisenberg et al., 2000 ); data reduction: EVALCCD (Duisenberg et al., 2003 ); program(s) used to solve structure: SIR97 (Altomare et al., 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ); software used to prepare material for publication: WinGX (Farrugia, 2012).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536813021612/yk2098sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813021612/yk2098Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813021612/yk2098Isup3.cml

checkCIF report

Comment top

Carbohydrate-based synthons have been used in a number of syntheses of complex natural chiral substances (Hanessian, 1993). Manipulation of the oxygenation pattern and stereochemistry of simple sugars proved to be a powerful mean to use nature-generated chirality. In this context D-mannitol plays an important role as a readily available chiral building block in organic synthesis (Babjak et al., 2002). In addition, mannitol and its derivatives are widely used as chiral reagents and chiral auxiliaries (Masaki et al., 1999) and can be transformed into biologically active and pharmaceutically important compounds (Lohray et al., 1999). As a continuation of our interest in oxidative processes mediated by transition metals oxo-species (Piccialli, Oliviero, Borbone et al., 2013; Piccialli, Tuzi, Oliviero et al., 2013; Piccialli, D'Errico, Borbone et al., 2013; Piccialli et al., 2012) we were interested in the synthesis and reactivity of functionalized fused bis-tetrahydrofurans.

In the title compound, molecule consists of two cis–fused tetrahydrofurane rings substituted at C2 and C5 positions (Fig.1). A local C₂ symmetry of the molecule is observed at the junction. Tetrahydrofurane rings are disordered in two different positions (occupancy factor refined to 0.735 (9) for the A position and 0.265 (9) for the B position). Both disordered O1/C1/C2/C3A/C4 and O1/C1/C2/C3B/C4 rings adopt an envelope conformation with O1 at the flap. The disordered O2A/C3A/C4/C5/C6A and O2B/C3B/C4/C5/C6B rings are both in the envelope conformation that differ for the atom at the flap (C6A and O2B, respectively). The molecule of the title compound does not contain strong H–bonding donor and the crystal packing is stabilized by normal weak intermolecular interactions.

Related literature top

For the use of carbohydrate in the synthesis of complex natural chiral substances, see: Hanessian (1993). For mannitol as chiral reagent and its biologically active derivatives, see: Babjak et al. (2002); Masaki et al. (1999); Lohray et al. (1999). For oxidative processes mediated by transition of oxo-species, see: Piccialli, Oliviero, Borbone et al. (2013); Piccialli, Tuzi, Oliviero et al. (2013); Piccialli, D'Errico, Borbone et al. (2013); Piccialli, Zaccaria, Oliviero et al. (2012). For the synthesis of the compound, see: Hockett et al. (1946).

Experimental top

The title compound was prepared according to a two-steps procedure starting from D-mannitol. Treatment of the latter with benzoyl chloride in pyridine for 16 h, followed by reaction with catalytic amounts of p-toluenesulfonic acid in 1,1,2,2-tetrachloroethane at reflux (Hockett et al., 1946) led to title compound as an amorphous white powder, after chromatography (CHCl₃ to CHCl₃–MeOH, 95:5). The whole process consists of a double migration of the primary benzoates to the adjacent alcoholic functions followed by double water elimination and bis-cyclization (C1/C4 and C3/C6 ether ring closure). Recrystallization from methanol gave elongated white crystals suitable for X-ray analysis.

1,4:3,6-dianhydro-2,5-di-O-benzoyl-D-mannitol: ¹H-NMR (200 MHz, CDCl₃) δ 8.10 (4H, d, J = 7.0 Hz), 7.58 (2H, t, J = 7.3 Hz), 7.45 (4H, t, J = 7.3 Hz), 5.42–5.27 (m, 2H), 4.95–4.83 (m, 2H), 4.15 (2H, dd, J = 9.4, 6.3 Hz), 4.02 (2H, dd, J = 9.4, 6.7 Hz); ¹³C-NMR (50 MHz, CDCl₃) δ 165.9, 133.2, 129.8, 129.4, 128.4, 80.6, 74.1, 70.7.

Computing details top

Data collection: COLLECT (Nonius, 1999); cell refinement: DIRAX/LSQ (Duisenberg et al., 2000); data reduction: EVALCCD (Duisenberg et al., 2003); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top

Fig. 1. ORTEP view of the title compound, with the atom labelling scheme. Thermal ellipsoids are drawn at 30% probability level. The disordered part with the minor occupancy factor is drawn by dashed lines.

(3R,3aR,6R,6aR)-Hexahydrofuro[3,2-b]furan-3,6-diyl dibenzoate top

Crystal data top

C₂₀H₁₈O₆	F(000) = 372
M_r = 354.34	D_x = 1.391 Mg m⁻³
Monoclinic, P2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 446 reflections
a = 10.0914 (15) Å	θ = 3.8–23.5°
b = 8.2388 (11) Å	µ = 0.10 mm⁻¹
c = 10.7592 (10) Å	T = 173 K
β = 108.913 (10)°	Block, white
V = 846.24 (19) Å³	0.50 × 0.20 × 0.10 mm
Z = 2

Data collection top

Bruker–Nonius KappaCCD diffractometer	2059 independent reflections
Radiation source: normal-focus sealed tube	1757 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.033
Detector resolution: 9 pixels mm^-1	θ_max = 27.5°, θ_min = 3.2°
CCD rotation images, thick slices scans	h = −12→13
Absorption correction: multi-scan (SADABS; Bruker, 2001)	k = −10→9
T_min = 0.950, T_max = 0.990	l = −13→13
7903 measured 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)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.073	H-atom parameters constrained
S = 1.11	w = 1/[σ²(F_o²) + (0.0287P)² + 0.1292P] where P = (F_o² + 2F_c²)/3
2059 reflections	(Δ/σ)_max = 0.001
263 parameters	Δρ_max = 0.14 e Å⁻³
12 restraints	Δρ_min = −0.20 e Å⁻³

Crystal data top

C₂₀H₁₈O₆	V = 846.24 (19) Å³
M_r = 354.34	Z = 2
Monoclinic, P2₁	Mo Kα radiation
a = 10.0914 (15) Å	µ = 0.10 mm⁻¹
b = 8.2388 (11) Å	T = 173 K
c = 10.7592 (10) Å	0.50 × 0.20 × 0.10 mm
β = 108.913 (10)°

Data collection top

Bruker–Nonius KappaCCD diffractometer	2059 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2001)	1757 reflections with I > 2σ(I)
T_min = 0.950, T_max = 0.990	R_int = 0.033
7903 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.035	12 restraints
wR(F²) = 0.073	H-atom parameters constrained
S = 1.11	Δρ_max = 0.14 e Å⁻³
2059 reflections	Δρ_min = −0.20 e Å⁻³
263 parameters

Special details top

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 > 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)
O1	0.64835 (16)	0.0655 (2)	0.86046 (14)	0.0337 (4)
O3	0.77544 (15)	0.3383 (2)	0.73544 (16)	0.0351 (4)
O4	0.68459 (17)	0.4767 (2)	0.54748 (17)	0.0449 (5)
O5	0.69994 (15)	−0.22410 (18)	0.78559 (13)	0.0282 (3)
O6	0.51687 (15)	−0.2810 (2)	0.85248 (15)	0.0385 (4)
C1	0.6475 (3)	0.2374 (3)	0.8702 (2)	0.0381 (6)
H1A	0.7348	0.2762	0.9366	0.046*
H1B	0.5668	0.2741	0.8961	0.046*
C2	0.6365 (2)	0.3022 (3)	0.7353 (2)	0.0322 (5)
H2	0.5777	0.4027	0.7162	0.039*
C4	0.5552 (2)	0.0247 (3)	0.73299 (19)	0.0252 (4)
H4	0.4576	0.0078	0.7343	0.030*
C5	0.6094 (2)	−0.1245 (3)	0.68230 (19)	0.0267 (5)
H5	0.5316	−0.1890	0.6207	0.032*
C7	0.7845 (2)	0.4329 (3)	0.6365 (2)	0.0305 (5)
C8	0.9319 (2)	0.4765 (3)	0.6514 (2)	0.0278 (4)
C9	0.9560 (2)	0.5661 (3)	0.5518 (2)	0.0339 (5)
H9	0.8800	0.5972	0.4769	0.041*
C10	1.0912 (3)	0.6098 (3)	0.5623 (2)	0.0422 (6)
H10	1.1082	0.6704	0.4938	0.051*
C11	1.2014 (3)	0.5664 (3)	0.6708 (3)	0.0436 (6)
H11	1.2941	0.5973	0.6774	0.052*
C12	1.1774 (2)	0.4781 (4)	0.7702 (3)	0.0459 (6)
H12	1.2537	0.4490	0.8456	0.055*
C13	1.0429 (2)	0.4318 (3)	0.7606 (2)	0.0362 (6)
H13	1.0266	0.3696	0.8286	0.043*
C14	0.6400 (2)	−0.2914 (3)	0.8676 (2)	0.0277 (5)
C15	0.7421 (2)	−0.3791 (3)	0.97809 (19)	0.0271 (5)
C16	0.6933 (2)	−0.4500 (3)	1.0721 (2)	0.0301 (5)
H16	0.5982	−0.4367	1.0668	0.036*
C17	0.7827 (2)	−0.5397 (3)	1.1732 (2)	0.0355 (5)
H17	0.7489	−0.5880	1.2373	0.043*
C18	0.9210 (3)	−0.5593 (3)	1.1812 (2)	0.0391 (6)
H18	0.9822	−0.6218	1.2503	0.047*
C19	0.9706 (2)	−0.4876 (3)	1.0884 (2)	0.0381 (6)
H19	1.0660	−0.5003	1.0945	0.046*
C20	0.8815 (2)	−0.3974 (3)	0.9868 (2)	0.0302 (5)
H20	0.9157	−0.3483	0.9234	0.036*
C3A	0.5619 (7)	0.1641 (7)	0.6404 (6)	0.0262 (11)	0.735 (9)
H3A	0.4650	0.1986	0.5873	0.031*	0.735 (9)
C6A	0.7006 (7)	−0.0439 (7)	0.6118 (7)	0.0287 (14)	0.735 (9)
H6A	0.7949	−0.0213	0.6745	0.034*	0.735 (9)
H6B	0.7108	−0.1161	0.5419	0.034*	0.735 (9)
O2A	0.6338 (4)	0.1033 (3)	0.5563 (3)	0.0297 (9)	0.735 (9)
C3B	0.5953 (15)	0.150 (2)	0.650 (2)	0.040 (6)	0.265 (9)
H3B	0.5162	0.1724	0.5676	0.048*	0.265 (9)
C6B	0.687 (2)	−0.0796 (14)	0.587 (2)	0.039 (6)	0.265 (9)
H6C	0.7746	−0.1422	0.6041	0.047*	0.265 (9)
H6D	0.6276	−0.0933	0.4946	0.047*	0.265 (9)
O2B	0.7130 (10)	0.0860 (10)	0.6220 (9)	0.032 (3)	0.265 (9)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0432 (9)	0.0322 (9)	0.0240 (7)	−0.0038 (7)	0.0085 (6)	−0.0056 (7)
O3	0.0256 (8)	0.0375 (9)	0.0432 (9)	−0.0012 (7)	0.0124 (7)	0.0140 (8)
O4	0.0315 (9)	0.0482 (11)	0.0457 (9)	−0.0019 (8)	−0.0005 (7)	0.0154 (9)
O5	0.0292 (7)	0.0308 (8)	0.0247 (7)	0.0038 (6)	0.0089 (6)	0.0030 (6)
O6	0.0261 (8)	0.0441 (10)	0.0437 (9)	−0.0019 (8)	0.0090 (7)	0.0120 (8)
C1	0.0452 (14)	0.0340 (14)	0.0420 (13)	−0.0139 (11)	0.0237 (11)	−0.0139 (11)
C2	0.0268 (11)	0.0274 (12)	0.0467 (13)	−0.0037 (9)	0.0177 (10)	−0.0038 (11)
C4	0.0222 (10)	0.0274 (11)	0.0261 (10)	−0.0028 (8)	0.0080 (8)	−0.0003 (9)
C5	0.0280 (11)	0.0297 (12)	0.0200 (9)	0.0010 (9)	0.0045 (8)	0.0010 (9)
C7	0.0305 (11)	0.0249 (12)	0.0346 (11)	−0.0017 (9)	0.0087 (9)	0.0018 (10)
C8	0.0292 (10)	0.0259 (11)	0.0286 (10)	−0.0026 (9)	0.0097 (8)	−0.0005 (9)
C9	0.0425 (13)	0.0308 (13)	0.0302 (11)	−0.0025 (11)	0.0140 (10)	0.0022 (10)
C10	0.0555 (15)	0.0351 (14)	0.0491 (14)	−0.0068 (12)	0.0349 (13)	0.0006 (12)
C11	0.0352 (13)	0.0444 (15)	0.0590 (15)	−0.0105 (12)	0.0260 (12)	−0.0118 (14)
C12	0.0294 (12)	0.0591 (18)	0.0469 (14)	−0.0013 (13)	0.0090 (10)	−0.0015 (14)
C13	0.0303 (11)	0.0452 (15)	0.0331 (11)	−0.0011 (11)	0.0103 (9)	0.0079 (11)
C14	0.0308 (11)	0.0235 (11)	0.0280 (10)	−0.0030 (9)	0.0087 (9)	−0.0030 (9)
C15	0.0299 (10)	0.0233 (11)	0.0270 (10)	−0.0002 (9)	0.0076 (8)	−0.0037 (9)
C16	0.0302 (11)	0.0302 (12)	0.0317 (11)	0.0038 (10)	0.0125 (9)	−0.0014 (10)
C17	0.0407 (13)	0.0367 (13)	0.0325 (11)	0.0058 (11)	0.0164 (10)	0.0058 (11)
C18	0.0381 (13)	0.0402 (15)	0.0364 (12)	0.0090 (11)	0.0084 (10)	0.0104 (11)
C19	0.0287 (12)	0.0403 (14)	0.0446 (13)	0.0046 (10)	0.0108 (10)	0.0031 (12)
C20	0.0300 (11)	0.0297 (12)	0.0314 (10)	−0.0010 (9)	0.0107 (9)	0.0004 (10)
C3A	0.027 (2)	0.025 (2)	0.028 (2)	0.0013 (19)	0.012 (2)	0.0032 (17)
C6A	0.034 (2)	0.034 (3)	0.021 (3)	0.009 (2)	0.0130 (18)	0.000 (2)
O2A	0.0313 (19)	0.0332 (13)	0.0277 (15)	0.0016 (10)	0.0137 (15)	0.0044 (10)
C3B	0.041 (7)	0.036 (7)	0.041 (7)	0.006 (4)	0.010 (5)	0.002 (4)
C6B	0.068 (11)	0.029 (7)	0.024 (8)	0.006 (6)	0.020 (7)	−0.009 (6)
O2B	0.026 (5)	0.040 (5)	0.033 (5)	0.001 (3)	0.014 (4)	−0.001 (3)

Geometric parameters (Å, º) top

O1—C1	1.421 (3)	C11—C12	1.378 (4)
O1—C4	1.429 (2)	C11—H11	0.9500
O3—C7	1.345 (3)	C12—C13	1.381 (3)
O3—C2	1.433 (2)	C12—H12	0.9500
O4—C7	1.199 (3)	C13—H13	0.9500
O5—C14	1.341 (3)	C14—C15	1.485 (3)
O5—C5	1.444 (2)	C15—C20	1.387 (3)
O6—C14	1.203 (3)	C15—C16	1.389 (3)
C1—C2	1.516 (3)	C16—C17	1.381 (3)
C1—H1A	0.9900	C16—H16	0.9500
C1—H1B	0.9900	C17—C18	1.379 (3)
C2—C3B	1.530 (13)	C17—H17	0.9500
C2—C3A	1.551 (5)	C18—C19	1.386 (3)
C2—H2	1.0000	C18—H18	0.9500
C4—C3B	1.50 (2)	C19—C20	1.384 (3)
C4—C5	1.516 (3)	C19—H19	0.9500
C4—C3A	1.536 (7)	C20—H20	0.9500
C4—H4	1.0000	C3A—O2A	1.422 (5)
C5—C6B	1.520 (6)	C3A—H3A	1.0000
C5—C6A	1.522 (4)	C6A—O2A	1.421 (6)
C5—H5	1.0000	C6A—H6A	0.9900
C7—C8	1.489 (3)	C6A—H6B	0.9900
C8—C13	1.385 (3)	C3B—O2B	1.418 (9)
C8—C9	1.386 (3)	C3B—H3B	1.0000
C9—C10	1.380 (3)	C6B—O2B	1.416 (10)
C9—H9	0.9500	C6B—H6C	0.9900
C10—C11	1.373 (4)	C6B—H6D	0.9900
C10—H10	0.9500

C1—O1—C4	106.71 (18)	C11—C12—H12	119.9
C7—O3—C2	115.89 (17)	C13—C12—H12	119.9
C14—O5—C5	115.68 (16)	C12—C13—C8	119.7 (2)
O1—C1—C2	106.30 (19)	C12—C13—H13	120.2
O1—C1—H1A	110.5	C8—C13—H13	120.2
C2—C1—H1A	110.5	O6—C14—O5	123.3 (2)
O1—C1—H1B	110.5	O6—C14—C15	124.1 (2)
C2—C1—H1B	110.5	O5—C14—C15	112.60 (17)
H1A—C1—H1B	108.7	C20—C15—C16	119.72 (19)
O3—C2—C1	107.69 (19)	C20—C15—C14	122.18 (19)
O3—C2—C3B	104.2 (5)	C16—C15—C14	118.04 (18)
C1—C2—C3B	101.9 (10)	C17—C16—C15	120.2 (2)
O3—C2—C3A	114.8 (3)	C17—C16—H16	119.9
C1—C2—C3A	104.0 (3)	C15—C16—H16	119.9
O3—C2—H2	110.1	C18—C17—C16	120.0 (2)
C1—C2—H2	110.1	C18—C17—H17	120.0
C3B—C2—H2	121.9	C16—C17—H17	120.0
C3A—C2—H2	110.1	C17—C18—C19	120.0 (2)
O1—C4—C3B	100.9 (7)	C17—C18—H18	120.0
O1—C4—C5	109.53 (17)	C19—C18—H18	120.0
C3B—C4—C5	98.3 (4)	C20—C19—C18	120.2 (2)
O1—C4—C3A	107.1 (3)	C20—C19—H19	119.9
C5—C4—C3A	106.0 (2)	C18—C19—H19	119.9
O1—C4—H4	111.3	C19—C20—C15	119.8 (2)
C3B—C4—H4	124.1	C19—C20—H20	120.1
C5—C4—H4	111.3	C15—C20—H20	120.1
C3A—C4—H4	111.3	O2A—C3A—C4	106.7 (4)
O5—C5—C4	113.31 (16)	O2A—C3A—C2	116.0 (4)
O5—C5—C6B	108.7 (9)	C4—C3A—C2	103.6 (4)
C4—C5—C6B	111.6 (5)	O2A—C3A—H3A	110.1
O5—C5—C6A	107.3 (3)	C4—C3A—H3A	110.1
C4—C5—C6A	99.9 (3)	C2—C3A—H3A	110.1
O5—C5—H5	111.9	O2A—C6A—C5	107.5 (3)
C4—C5—H5	111.9	O2A—C6A—H6A	110.2
C6B—C5—H5	98.5	C5—C6A—H6A	110.2
C6A—C5—H5	111.9	O2A—C6A—H6B	110.2
O4—C7—O3	123.5 (2)	C5—C6A—H6B	110.2
O4—C7—C8	124.4 (2)	H6A—C6A—H6B	108.5
O3—C7—C8	112.14 (18)	C6A—O2A—C3A	107.7 (4)
C13—C8—C9	120.1 (2)	O2B—C3B—C4	106.1 (13)
C13—C8—C7	122.15 (19)	O2B—C3B—C2	110.4 (9)
C9—C8—C7	117.73 (19)	C4—C3B—C2	106.3 (13)
C10—C9—C8	119.5 (2)	O2B—C3B—H3B	111.3
C10—C9—H9	120.3	C4—C3B—H3B	111.3
C8—C9—H9	120.3	C2—C3B—H3B	111.3
C11—C10—C9	120.6 (2)	O2B—C6B—C5	98.6 (6)
C11—C10—H10	119.7	O2B—C6B—H6C	112.0
C9—C10—H10	119.7	C5—C6B—H6C	112.0
C10—C11—C12	120.0 (2)	O2B—C6B—H6D	112.0
C10—C11—H11	120.0	C5—C6B—H6D	112.0
C12—C11—H11	120.0	H6C—C6B—H6D	109.7
C11—C12—C13	120.2 (2)	C6B—O2B—C3B	108.5 (8)

C4—O1—C1—C2	−36.6 (2)	C14—C15—C16—C17	176.8 (2)
C7—O3—C2—C1	−164.35 (19)	C15—C16—C17—C18	0.0 (4)
C7—O3—C2—C3B	87.9 (10)	C16—C17—C18—C19	0.6 (4)
C7—O3—C2—C3A	80.4 (4)	C17—C18—C19—C20	−0.6 (4)
O1—C1—C2—O3	−95.8 (2)	C18—C19—C20—C15	−0.1 (4)
O1—C1—C2—C3B	13.5 (5)	C16—C15—C20—C19	0.7 (3)
O1—C1—C2—C3A	26.3 (3)	C14—C15—C20—C19	−176.7 (2)
C1—O1—C4—C3B	43.2 (4)	O1—C4—C3A—O2A	108.9 (3)
C1—O1—C4—C5	146.16 (18)	C3B—C4—C3A—O2A	46 (3)
C1—O1—C4—C3A	31.6 (3)	C5—C4—C3A—O2A	−8.0 (4)
C14—O5—C5—C4	63.8 (2)	O1—C4—C3A—C2	−14.1 (4)
C14—O5—C5—C6B	−171.5 (7)	C3B—C4—C3A—C2	−77 (3)
C14—O5—C5—C6A	173.1 (3)	C5—C4—C3A—C2	−130.9 (3)
O1—C4—C5—O5	23.7 (2)	O3—C2—C3A—O2A	−6.4 (6)
C3B—C4—C5—O5	128.4 (7)	C1—C2—C3A—O2A	−123.8 (4)
C3A—C4—C5—O5	138.9 (3)	C3B—C2—C3A—O2A	−42 (5)
O1—C4—C5—C6B	−99.4 (11)	O3—C2—C3A—C4	110.2 (3)
C3B—C4—C5—C6B	5.3 (13)	C1—C2—C3A—C4	−7.2 (4)
C3A—C4—C5—C6B	15.8 (11)	C3B—C2—C3A—C4	75 (5)
O1—C4—C5—C6A	−90.2 (3)	O5—C5—C6A—O2A	−153.4 (4)
C3B—C4—C5—C6A	14.6 (8)	C4—C5—C6A—O2A	−35.0 (6)
C3A—C4—C5—C6A	25.0 (4)	C6B—C5—C6A—O2A	109 (5)
C2—O3—C7—O4	−5.1 (3)	C5—C6A—O2A—C3A	32.0 (7)
C2—O3—C7—C8	174.68 (19)	C4—C3A—O2A—C6A	−14.5 (6)
O4—C7—C8—C13	175.5 (2)	C2—C3A—O2A—C6A	100.3 (6)
O3—C7—C8—C13	−4.2 (3)	O1—C4—C3B—O2B	84.2 (10)
O4—C7—C8—C9	−3.9 (3)	C5—C4—C3B—O2B	−27.7 (11)
O3—C7—C8—C9	176.4 (2)	C3A—C4—C3B—O2B	−156 (4)
C13—C8—C9—C10	0.2 (4)	O1—C4—C3B—C2	−33.4 (9)
C7—C8—C9—C10	179.6 (2)	C5—C4—C3B—C2	−145.2 (7)
C8—C9—C10—C11	−0.6 (4)	C3A—C4—C3B—C2	87 (3)
C9—C10—C11—C12	0.2 (4)	O3—C2—C3B—O2B	9.7 (18)
C10—C11—C12—C13	0.5 (4)	C1—C2—C3B—O2B	−102.2 (15)
C11—C12—C13—C8	−0.9 (4)	C3A—C2—C3B—O2B	157 (7)
C9—C8—C13—C12	0.5 (4)	O3—C2—C3B—C4	124.4 (6)
C7—C8—C13—C12	−178.9 (2)	C1—C2—C3B—C4	12.4 (9)
C5—O5—C14—O6	5.3 (3)	C3A—C2—C3B—C4	−88 (5)
C5—O5—C14—C15	−174.67 (17)	O5—C5—C6B—O2B	−107.4 (12)
O6—C14—C15—C20	175.5 (2)	C4—C5—C6B—O2B	18.3 (17)
O5—C14—C15—C20	−4.5 (3)	C6A—C5—C6B—O2B	−20 (3)
O6—C14—C15—C16	−1.9 (3)	C5—C6B—O2B—C3B	−37 (2)
O5—C14—C15—C16	178.10 (19)	C4—C3B—O2B—C6B	44.0 (17)
C20—C15—C16—C17	−0.6 (3)	C2—C3B—O2B—C6B	158.7 (14)

Hydrogen-bond geometry (Å, º) top

Cg is the centroid of the C15–C20 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1A···Cgⁱ	0.99	2.60	3.419 (3)	149

Symmetry code: (i) x, y+1, z.

Hydrogen-bond geometry (Å, º) top

Cg is the centroid of the C15–C20 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1A···Cgⁱ	0.99	2.60	3.419 (3)	149

Symmetry code: (i) x, y+1, z.

Acknowledgements

The authors thank the Centro Interdipartimentale di Metodologie Chimico–Fisiche, Università degli Studi di Napoli "Federico II" for X-ray and NMR facilities.

References

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Volume 69| Part 9| September 2013| Pages o1396-o1397

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