[H-].[Na+].[OH:3][C:4]1[CH:14]=[CH:13][C:7]([C:8]([O:10][CH2:11][CH3:12])=[O:9])=[CH:6][C:5]=1[I:15].C1OCCOCCOCCOCCOC1.[C:31]1([CH2:37][CH:38]=[CH:39][CH2:40]Br)[CH:36]=[CH:35][CH:34]=[CH:33][CH:32]=1.Cl>C1COCC1>[I:15][C:5]1[CH:6]=[C:7]([CH:13]=[CH:14][C:4]=1[O:3][CH2:40]/[CH:39]=[CH:38]/[CH2:37][C:31]1[CH:36]=[CH:35][CH:34]=[CH:33][CH:32]=1)[C:8]([O:10][CH2:11][CH3:12])=[O:9]To a suspension of NaH (0.82 g, 20.5 mmol) in THF (40 ml), a solution of ethyl 4-hydroxy-3-iodo-benzoate (5.0 g, 17.1 mmol) in THF (40 ml), then 15-crown-5 (4.0 ml, 25.6 mmol) and finally a solution of 4-phenylbut-2-enyl bromide (5.41 g, 25.6 mmol) in THF (50 ml) were added subsequently at 0° C. The reaction mixture was kept under stirring at room temperature for 10 minutes and then warmed to 50° C. for 6 h. After equilibration at room temperature, 3 N HCl was added (30 ml) and the mixture poured into a separatory funnel. The organic layer was separated and the aqueous layer extracted with ethyl acetate (3×30 ml). The collected organic layers were washed with saturated aqueous sodium chloride and dried over sodium sulfate. The solvent was eliminated with a rotary evaporator. The residue was purified by flash chromatography on silica gel (petroleum ether/ethyl acetate=95/5) affording 5.94 g of the title compound (82% yield).
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