thionyl chloride T=50°C; 1 h;

1: 90 percent / hydrazine hydrate, hydrazine dihydrochloride / ethane-1,2-diol / 2 h / 140 °C 2: 100 percent / thionyl chloride / 1 h / 50 °C View Scheme

1: Br2, AcOH / 21 h / Ambient temperature 2: NH2NH2 3: SOCl2 View Scheme