1: 98.6 percent / O3 / CH2Cl2 / 0.25 h / -78 °C 2: 101 mg / 2.5N NaOH / methanol / 12 h / Heating 3: 116 mg / triethylamine / butan-1-ol / 40 h / Heating 4: 1.) acetic anhydride, 2.) NH3(gas) / 1.) room temperature, 2 h, 2.) methanol, 45 deg C, 16 h 5: 80 percent / 2M HCl / methanol / 16 h / Ambient temperature View Scheme