1: 87 percent / pyridinium chlorochromate / CH2Cl2 / 2 h / 15 °C 2: 92 percent / 3percent NaOH / ethanol / 0.17 h / 15 °C 3: 100 percent 4: 65 percent / NaBH4 / methanol / 2 h / 65 °C 5: 85 percent / active manganese dioxide / hexane / 0.5 h / 0 °C View Scheme