1: lithium diethylamide / benzene / Heating 2: pyridine / 1.5 h / Ambient temperature 3: sodium bicarbonate / methanol 4: DIBAL / tetrahydrofuran / 2 h / ice bath 5: 73 percent / tBuOOH, VO(acac)2 / benzene / under standard Sharpless conditions 6: CrO3-pyridine / CH2Cl2 / Ambient temperature 7: silica gel / eluted the column with hexane-ether View Scheme

1: lithium diethylamide / benzene / Heating 2: pyridine / 1.5 h / Ambient temperature 3: sodium bicarbonate / methanol 4: DIBAL / tetrahydrofuran / 2 h / ice bath View Scheme