1.1: isopropylmagnesium chloride / tetrahydrofuran; diethyl ether / 2 h / -10 °C 1.2: tetrahydrofuran; diethyl ether / -78 °C 1.3: 54 percent / aq.HCl / H2O / pH 1 2.1: 72 percent / hydrogen; triethylamine / palladium on charcoal / methanol / 2 h / 25 °C / 760 Torr View Scheme

phosphorus tribromide T=150°C; 0.75 h;

1: 86 percent / bromine; potassium acetate / acetic acid / 2 h / 80 °C 2: 77 percent / phosphorus tribromide / 0.75 h / 150 °C View Scheme

1: 70 percent / aq. hydrogen peroxide / H2O; tetrahydrofuran / 2 h / 80 °C 2: 86 percent / bromine; potassium acetate / acetic acid / 2 h / 80 °C 3: 77 percent / phosphorus tribromide / 0.75 h / 150 °C View Scheme

hydrazine hydrate in ethanol