1.1: DIBAL-H / tetrahydrofuran; hexane / 2 h / -78 °C 2.1: tetrahydrofuran / 80 °C 2.2: 0.473 g / PhLi / tetrahydrofuran / 0.67 h 3.1: p-toluenesulfonic acid monohydrate / methanol / 4 h / 50 °C 4.1: aq. NaIO4 / CH2Cl2 / 0.75 h 5.1: 0.269 g / NaBH4 / methanol / 1 h / 0 °C 6.1: 92 percent / Bu4NF / tetrahydrofuran / 1 h / 20 °C View Scheme