(1SR,2RS,3SR,5SR,6RS)-6-[(Z)-1-Acet­oxy-2-phenyl­ethen­yl]-3-eth­oxy-2-phenyl­bicyclo­[3.1.0]hexan-1-yl acetate

Wen-Xiang Hu; Gao Xu; Guo-Qiang Wei

doi:10.1107/S1600536811001760

. 2011 Jan 29;67(Pt 2):o512. doi: 10.1107/S1600536811001760

(1SR,2RS,3SR,5SR,6RS)-6-[(Z)-1-Acetoxy-2-phenylethenyl]-3-ethoxy-2-phenylbicyclo[3.1.0]hexan-1-yl acetate

Wen-Xiang Hu ^a,^*, Gao Xu ^a, Guo-Qiang Wei ^a

PMCID: PMC3051501 PMID: 21523163

Abstract

The molecule of the title compound, C₂₆H₂₈O₅, is chiral with five stereogenic centres; however, the centrosymmetric triclinic group gives a racemic crystal. The fused ring system adopta boat conformation in which the cyclopropane ring plane is roughly perpendicular to the styryl group plane, forming a dihedral angle of 74.78 (19)°. The dihedral angle between the two benzene rings is 77.24 (6)°.

Related literature

For related structures, see: Li et al. (2008 ▶); Zhang et al. (2008 ▶). For general backgound to the bicyclo[3.1.0]hexane unit, see: Donaldson (2001 ▶); Ezzitouni & Marquez (1997 ▶); Hanessian et al. (1995 ▶); Monn et al. (1997 ▶).

Experimental

Crystal data

C₂₆H₂₈O₅
M _r = 420.48
Triclinic,
a = 5.8585 (14) Å
b = 12.368 (3) Å
c = 15.852 (4) Å
α = 73.170 (6)°
β = 88.967 (9)°
γ = 81.761 (7)°
V = 1087.7 (4) Å³
Z = 2
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 103 K
0.43 × 0.37 × 0.10 mm

Data collection

Rigaku AFC10/Saturn724+ diffractometer
10211 measured reflections
4888 independent reflections
2841 reflections with I > 2σ(I)
R _int = 0.053

Refinement

R[F ² > 2σ(F ²)] = 0.048
wR(F ²) = 0.076
S = 0.94
4888 reflections
277 parameters
H-atom parameters constrained
Δρ_max = 0.58 e Å⁻³
Δρ_min = −0.32 e Å⁻³

Data collection: CrystalClear (Rigaku, 2008) ▶; cell refinement: CrystalClear ▶; data reduction: CrystalClear ▶; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: DIAMOND (Brandenburg, 1999 ▶); software used to prepare material for publication: publCIF (Westrip, 2010 ▶).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811001760/kp2298sup1.cif

e-67-0o512-sup1.cif^{(23KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536811001760/kp2298Isup2.hkl

e-67-0o512-Isup2.hkl^{(239.4KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

This work was supported by the National Natural Science Foundation of China (No. 20872095). Special thanks are given to Dr Huang Xiaogen and Dr Chen Zili for their generous help.

supplementary crystallographic information

Comment

Small-ring compounds and their derivatives arouse considerable interest because their energy content relative to their acyclic counterparts often results in unexpected properties. Bicyclo[3.1.0]hexane, which contained a cyclopropane unit, is an important structural element in a wide range of naturally occurring compounds (Hanessian et al., 1995; Donaldson, 2001), and as a privileged unit in medicinal chemistry (Monn et al., 1997; Ezzitouni et al., 1997) since it possesses unique stereochemical and electronic properties in conjunction with high metabolic stability. In this paper, we will report the structure of the title compound, a new polysubstituted bicyclo[3.1.0]hexane compound, which was simply prepared from the gold catalysed reaction of vinyl ether with propargylic ester.

The title molecule (Fig.1), is mainly composed of two fused rings A (C1—C5—C6), and B (C1—C2—C3—C4—C5). The ring B has an envelope conformation, C3 and ring A lie to the same side of the plane defined by C1—C2—C4—C5. The ring A is roughly perpendicular to the styryl group and almost parallels the cyclopentane-attached benzene ring. The dihedral angle between ring A and the styryl group is 74.782 (99)°, while the dihedral angle data between two benzene rings is 77.235 (58)°.

Experimental

Under an atmosphere of nitrogen, IprAuNTf₂(12.92 mg, 0.0141 mmol) was added to a solution of 3-phenyl-1-propyn-3-yl acetate (98.46 mg, 0.565 mmol) and vinyl ethyl ether (0.8 ml) in 11 ml dry 1,2-dichloroethane. After stirring for 3 h, the solution was concentrated in vacuo. The crude product was purified by flash chromatography on silica gel (diethyl ether:n-hexane = 1:20) to give the title compound as a white solid, which was then recrystallized from EtOAc and pentane (EtOAc:pentane = 1:9) to afford a colourless platee-like crystals.