1: Et3N / tetrahydrofuran; H2O / 1 h / Ambient temperature 2: 3 percent / O3 / CH2Cl2 / -78 °C 3: 60 percent / n-BuLi / tetrahydrofuran / -78 deg C, 2 min -> 0 deg C, 1 h 4: Jones reagent 5: KOH / 24 h / Ambient temperature View Scheme