1: 72 percent / NH2-NH2 / ethanol / 4 h / Ambient temperature 2: 82 percent / NaBH4 / ethanol / 4 h / 40 °C 3: 80 percent / p-toluenesulfonic acid / 10percent Pd/C / dioxane / 8 h / 100 °C View Scheme

hydrazine in ethanol 4 h; Ambient temperature;

in ethanol 4 h; Ambient temperature;