[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([Cl:8])=[CH:4][C:3]=1[CH2:9][CH2:10][CH2:11][CH2:12][C:13]([O:15]C)=[O:14].[Li+].[OH-]>C1COCC1.CO>[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([Cl:8])=[CH:4][C:3]=1[CH2:9][CH2:10][CH2:11][CH2:12][C:13]([OH:15])=[O:14]Methyl 5-(2,5-Dichlorophenyl)pentanoate (1.10 g, 4.2 mmol) was dissolved in 20 ml THF and 7 mL methanol. 1 N LiOH (12 mL) was added dropwise and the reaction was stirred at room temperature for 2 days. The reaction was worked-up by acidification with 2 N HCl and removal of most of the THF and methanol on a rotary evaporator followed by extraction of the aqueous residue with ethyl acetate. The organic phase was washed with water and saturated brine, dried over sodium sulfate and concentrated to a residue. Flash chromatography (silica gel; hexane/toluene (19/1) with 1% acetic acid) of the residue gave 725 mg (70%) of a white solid.
Wird geladen…
