1: 1.) NaOH / 1.) ethanol, RT, 1 h, 2.) ether, acetone 2: 96 percent / CrO3, aq. H2SO4 / acetone / 0.83 h View Scheme

1: 70 percent / NaOMe / 24 h / 20 °C 2: 80 percent / MnO2 / CH2Cl2 / 24 h / 20 °C View Scheme

1: 70 percent / NaOMe / 24 h / 20 °C 2: 54 percent / NBS / CCl4 / 5 h / Heating View Scheme

1: 67 percent / sodium methoxide / 18 h / Ambient temperature 2: 86 percent / manganese dioxide / CH2Cl2 / 3 h / Heating 3: 1.) acetic acid, Br2 / 2.) DMF, 70 deg C, 1.5 h View Scheme

1: 67 percent / sodium methoxide / 18 h / Ambient temperature 2: 86 percent / manganese dioxide / CH2Cl2 / 3 h / Heating 3: 1.) acetic acid, Br2 / 2.) DMF, 70 deg C, 3 h 4: 16 h / 80 °C View Scheme