1: 96 percent / NaBH4, NaOH / methanol / 12 h 2: 92 percent / 85percent H2SO4 / 2 h / 110 - 120 °C 3: 1.) O3, 2.) 35percent aq. H2O2, 5percent aq. NaOH / 1.) CH2Cl2, RT, 24 h, 2.) EtOH, reflux, 24 h View Scheme