1.1: NaBH4 / methanol / 1.5 h / 0 - 20 °C 2.1: 0.638 g / sulfuric acid / 0.5 h / Heating 3.1: O3 / CH2Cl2 / 0.03 h / -78 °C 3.2: 73 percent / dimethyl sulfide / CH2Cl2 / 20 h / -78 - 20 °C 4.1: 100 percent / NaOH / H2O / 1 h / 20 °C 5.1: 73 percent / CuO; potassium carbonate / pyridine / 4 h / Heating View Scheme