Ethyl 2-hydr­oxy-5-oxo-4-phenyl-2,3,4,5-tetra­hydro­pyrano[3,2-c]chromene-2-carboxyl­ate

Wei Zhang; Guangcun Zhang; Bailin Li; Yifeng Wang

doi:10.1107/S1600536809028311

. 2009 Jul 25;65(Pt 8):o1969. doi: 10.1107/S1600536809028311

Ethyl 2-hydroxy-5-oxo-4-phenyl-2,3,4,5-tetrahydropyrano[3,2-c]chromene-2-carboxylate

Wei Zhang ^a, Guangcun Zhang ^a, Bailin Li ^a,^b, Yifeng Wang ^a,^*

PMCID: PMC2977402 PMID: 21583645

Abstract

The main structural unit of the title compoud, C₂₁H₁₈O₆, is a fused three-ring group consisting of coumarin and tetrahydropyrane ring systems. Two C atoms of the tetrahydropyran ring are displaced by 0.295 (3) and −0.360 (2) Å from the mean plane of coumarin ring. The dihedral angle between the phenyl and coumarin rings is 73.94 (3)°. Intermolecular O—H⋯O hydrogen bonds are present in the crystal structure.

Related literature

For the synthesis of (E)-ethyl 2-oxo-4-phenylbut-3-enoate, see: Vaijayanthi & Chadha (2007 ▶).

Experimental

Crystal data

C₂₁H₁₈O₆
M _r = 366.37
Monoclinic,
a = 5.4988 (2) Å
b = 14.9975 (5) Å
c = 21.342 (1) Å
β = 98.5487 (13)°
V = 1740.48 (12) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 296 K
0.41 × 0.39 × 0.14 mm

Data collection

Rigaku R-AXIS RAPID diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 2005 ▶) T _min = 0.954, T _max = 0.986
16523 measured reflections
3422 independent reflections
2568 reflections with F ² > 2σ(F ²)
R _int = 0.026

Refinement

R[F ² > 2σ(F ²)] = 0.035
wR(F ²) = 0.080
S = 1.00
3422 reflections
246 parameters
H-atom parameters constrained
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.19 e Å⁻³

Data collection: PROCESS-AUTO (Rigaku, 2006 ▶); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku, 2007 ▶); program(s) used to solve structure: SHELXL97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶); software used to prepare material for publication: CrystalStructure.

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809028311/pk2181sup1.cif

e-65-o1969-sup1.cif^{(20.7KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809028311/pk2181Isup2.hkl

e-65-o1969-Isup2.hkl^{(167.9KB, hkl)}

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

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H101⋯O2ⁱ	0.82	2.30	2.9198 (15)	132
O1—H101⋯O5	0.82	2.17	2.6628 (17)	119

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Symmetry code: (i) Inline graphic .

Acknowledgments

We are grateful for the help of Professor Jian-Ming Gu of Zhejiang University.

supplementary crystallographic information

Comment

Coumarin derivatives are widely distributed in nature and are used as versatile intermediates in organic and natural product synthesis. Moreover, this class of compound possess a wide range of biological activities, including anticoagulant and HIV protease inhibition properties. The title compound, which is readily synthesized from commercially available 4-hydroxycoumarin and (E)-ethyl 2-oxo- 4-phenylbut-3-enoate, can act as an intermediate in organic and natural product synthesis. In this article, the crystal structure of the title compound, ethyl 2-hydroxy-5-oxo-4-phenyl-2,3,4,5-tetrahydropyrano[3,2- c]chromene-2-carboxylate was described (Fig. 1). The main structural unit is a three-ring group consisting of a coumarin ring and a tetrahydropyrane. Two carbon atoms of the tetrahydropyrane structure are not coplanar with the coumarin backbone: one carbon atom lies 0.295 (3) Å from the mean plane of coumarin ring and the other lies 0.360 (2) Å from the plane in opposite direction. The dihedral angle between benzene and coumarin rings is 73.94 (3) °. The distance from O1 of the hydroxyl group to coumarin plane is 1.664 (2) Å. In addition, intermolecular O—H···O hydrogen bonds in the crystal are observed (Fig. 2).

Experimental

The title compound was synthesized by treating (E)-ethyl 2-oxo-4-phenylbut-3-enoate (2.04 g,10 mmol) with 4-hydroxycoumarin (1.62 g, 10 mmol) in the presence of triethylamine as a catalyst in dichloromethane (30 ml) under stirring at room temperature for 24 h. The solvent was distilled under vacuum, and the residue was purified by flash column chromatography (silica gel, Hex/AcOEt, v/v, 3:1) giving the title compound (3.3 g, 90%). The compound (E)-ethyl 2-oxo-4-phenylbut-3-enoate was obtained from commercially available benzaldehyde by condensation with pyruvic acid and subsequent esterification with ethanol. Suitable crystals of the title compound were obtained by slow evaporation of dichloromethane solution at room temperature.