After addition of tetrabutylammonium fluoride (a 1M tetrahydrofuran solution, 0.978 ml, 0.978 mmol) to a solution of 2-[5-(t-butyldimethylsilyloxy)-1-[(4-chlorophenyl)sulfonyl]-1-methylpentyl]-1,4-difluorobenzene (164 mg, 0.326 mmol) in tetrahydrofuran (4 ml), the mixture was stirred at room temperature for 3 hours. The reaction mixture was diluted with diethyl ether, washed successively with saturated ammonium chloride, water and brine, dried over MgSO4, and then concentrated. The residue thus obtained was purified by medium-pressure chromatography on a silica gel column (50% ethyl acetate-hexane), whereby the title compound (122 mg, 96%) was obtained as a colorless oil.
