sodium hydroxide; potassium permanganate in water 1.5 h; Ambient temperature;

hydrogenchloride in acetic acid 8 h; Heating;

sulfuric acid 1.5 h; Heating;

1: 89 percent / ethanol / 1 h / Ambient temperature 2: 86 percent / 5percent NaHCO3 / H2O / 0.08 h / Heating 3: 94 percent / 5N aq. HCl, 37percent aq. formaldehyde / H2O / 0.5 h / Heating 4: 76 percent / 0.1 N NaOH, 1percent KMnO4 / H2O / 1.5 h / Ambient temperature View Scheme

1: 63 percent / dimethylformamide / 3 h / 180 °C 2: 34 percent / conc. hydrochloric acid / acetic acid / 8 h / Heating View Scheme

1: 76 percent / dimethylformamide / 3 h / 180 °C 2: 34 percent / conc. hydrochloric acid / acetic acid / 8 h / Heating View Scheme

1: 94 percent / 5N aq. HCl, 37percent aq. formaldehyde / H2O / 0.5 h / Heating 2: 76 percent / 0.1 N NaOH, 1percent KMnO4 / H2O / 1.5 h / Ambient temperature View Scheme