1: 82 percent / Br2 2: 60 percent / KOH / methanol / Ambient temperature 3: 83 percent / Zn(BH4)2 / benzene; diethyl ether / 0.5 h / Ambient temperature View Scheme

1: toluene-4-sulfonic acid / 14 h / 20 °C 2: N-bromosuccinmide / water; acetone / 72 h / 20 °C 3: pyridine / 4-(N,N-dimethlyamino)pyridine / dichloromethane / 12 h / 20 °C 4: bromine; acetic acid / 48 h / 20 °C 5: potassium hydroxide / methanol / 20 °C 6: toluene-4-sulfonic acid / 20 °C 7: zinc(II) chloride; sodium tetrahydroborate / diethyl ether View Scheme

1: hydrogenchloride / Reflux 2: pyridine / 4-(N,N-dimethlyamino)pyridine / dichloromethane / 12 h / 20 °C 3: bromine; acetic acid / 48 h / 20 °C 4: potassium hydroxide / methanol / 20 °C 5: toluene-4-sulfonic acid / 20 °C 6: zinc(II) chloride; sodium tetrahydroborate / diethyl ether View Scheme

1: N-bromosuccinmide / water; acetone / 72 h / 20 °C 2: pyridine / 4-(N,N-dimethlyamino)pyridine / dichloromethane / 12 h / 20 °C 3: bromine; acetic acid / 48 h / 20 °C 4: potassium hydroxide / methanol / 20 °C 5: toluene-4-sulfonic acid / 20 °C 6: zinc(II) chloride; sodium tetrahydroborate / diethyl ether View Scheme