1: With diisobutylaluminium hydride in tetrahydrofuran; toluene T=-78 - 23°C; 18 h; 2: With hydrogenchloride; water in tetrahydrofuran; toluene T=0 - 23°C; 1 h;

1.1: bromine; acetic acid / methanol / 2 h / 20 °C / Cooling with ice 2.1: hydrogenchloride; sodium nitrite / water / 0.5 h / 0 °C 2.2: 4 h / 0 - 50 °C 3.1: diisobutylaluminium hydride / toluene; tetrahydrofuran / -78 - 20 °C 3.2: 1 h / 20 °C View Scheme

1.1: hydrogenchloride; sodium nitrite / water / 0.5 h / 0 °C 1.2: 4 h / 0 - 50 °C 2.1: diisobutylaluminium hydride / toluene; tetrahydrofuran / -78 - 20 °C 2.2: 1 h / 20 °C View Scheme

1.1: hydrogenchloride; sodium nitrite / water / 0.5 h / 0 °C 1.3: 4 h / 0 - 50 °C 2.1: diisobutylaluminium hydride / toluene; tetrahydrofuran / -78 - 20 °C 2.2: 0 - 20 °C View Scheme

sodium chlorite; sodium dihydrogenphosphate; 2-methyl-but-2-ene in water; tert-butyl alcohol T=23°C; 0.5 h;