[CH:1]1([C:6]2[CH:11]=[CH:10][C:9]([C:12](=[O:14])[CH3:13])=[CH:8][CH:7]=2)[CH2:5][CH2:4][CH2:3][CH2:2]1.II.[CH2:17]([O:19][C:20](=[O:23])[CH2:21]Br)[CH3:18].Cl>C1C=CC=CC=1.[Zn]>[OH:14][C:12]([C:9]1[CH:8]=[CH:7][C:6]([CH:1]2[CH2:5][CH2:4][CH2:3][CH2:2]2)=[CH:11][CH:10]=1)([CH3:13])[CH2:21][C:20]([O:19][CH2:17][CH3:18])=[O:23]
To a refluxing mixture of 4′-cyclopentylacetophenone (17 g), I2 (5 mg) and Zn dust (12 g) in benzene (150 ml) was added ethylbromoacetate (11 ml) dropwise over 30 minutes. The mixture was refluxed for next 45 min and then cooled to room temperature. It was acidified with 10% aqueous HCl solution (150 ml) and organic layer was separated out. The organic layer was washed with water, dried (Na2SO4) and concentrated. The crude product was purified by column chromatography on silica gel to furnish 22 g (88.1% yield) of ethyl 3-hydroxy-3-(4′-cyclopentylphenyl)-butanoate (2a) as oil.
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