To a solution of 6,6-bis-(4-fluoro-phenyl)-1-[4-(3,4,5,-trimethoxy-benzoyl)-piperazin-1-yl]-hex-5-en-1-one (1.3 g, 2.3 mmol) in dry THF (20 ml) was added NaBH4 (22 mg, 0.58 mmol) followed by dropwise addition of BF3.Et2O (0.2 ml, 1.43 mmol). The resulting mixture stirred at r.t. for 3 hrs and excess NaBH4 decomposed by addition of water(0.1 ml). The mixture was then oxidized by adding 3M NaOH (0.3 ml) followed by addition of H2O2 (0.5 ml, 3 mmol). After stirring for 1.5 hrs at 30-40° C., the mixture was washed with brine (30 ml). The organic layer dried over MgSO4 and evaporated. The residue was purified by column chromatography using EtOAc:hexane (3:1) to give the desired product in 64% yield.
