1: 82 percent / dimethylformamide / Ambient temperature; overnight 2: 89 percent / p-toluenesulphonic acid / CH2Cl2; methanol / 3 h / Ambient temperature 3: 88 percent / aq. hydrochloric acid / 0.5 h / Heating View Scheme

1: benzene; dimethylformamide / 18 h / -15 - 20 °C 2: toluene-p-sulphonic acid / methanol; CH2Cl2 3: HCl / 0.5 h / Heating View Scheme

1: 82 percent / dimethylformamide / Ambient temperature; overnight 2: 89 percent / p-toluenesulphonic acid / CH2Cl2; methanol / 3 h / Ambient temperature 3: 88 percent / aq. hydrochloric acid / 0.5 h / Heating View Scheme

1: benzene; dimethylformamide / 18 h / -15 - 20 °C 2: toluene-p-sulphonic acid / methanol; CH2Cl2 3: HCl / 0.5 h / Heating View Scheme

1: Et3N / CH2Cl2 / Ambient temperature 2: H2 / Raney Ni / dioxane 3: H+ 4: NH3(l) / 18 h / Ambient temperature 5: aq. HCl / 0.08 h View Scheme