potassium hydroxide; hydrazine hydrate in ethanol 1 h; Heating;

phosphoric acid T=170 - 180°C; 12 h;

2: 95 percent / hydrazine hydrate, KOH / ethanol / 1 h / Heating View Scheme

1: 83 percent / 98percent H2SO4 / benzene / 48 h / Heating 2: 81 percent / K2CO3 anhydr. / acetone / 2 h / Heating 3: 60 percent / Na / toluene; ethanol / 11 h / Heating 4: sodium borohydride / methanol / 0.5 h / Ambient temperature 5: 95 percent / 85percent phosphoric acid / 12 h / 170 - 180 °C View Scheme

1: 60 percent / Na / toluene; ethanol / 11 h / Heating 2: sodium borohydride / methanol / 0.5 h / Ambient temperature 3: 95 percent / 85percent phosphoric acid / 12 h / 170 - 180 °C View Scheme

1: sodium borohydride / methanol / 0.5 h / Ambient temperature 2: 95 percent / 85percent phosphoric acid / 12 h / 170 - 180 °C View Scheme

1: 81 percent / K2CO3 anhydr. / acetone / 2 h / Heating 2: 60 percent / Na / toluene; ethanol / 11 h / Heating 3: sodium borohydride / methanol / 0.5 h / Ambient temperature 4: 95 percent / 85percent phosphoric acid / 12 h / 170 - 180 °C View Scheme

in N,N-dimethyl-formamide T=208°C; 10 h;