1: 90 percent / sodium hydride / tetrahydrofuran / 4 h / Ambient temperature 2: 100 percent / toluene-4-sulphonic acid / benzene / 0.03 h / Heating View Scheme

Multi-step reaction with 4 steps 1: 44 percent / CH2Cl2 / 20 h / 25 °C2: 90 percent / aq. H2O2 (30 percent), acetic acid / 1 h / 20 °C3: 100 percent / aq. HI (57 percent) / benzene / 2 h4: 68 percent / Me3SiCl, Zn / tetrahydrofuran / Heating  

Multi-step reaction with 5 steps 1: 95 percent / glacial acetic acid, DDQ / diethyl ether / 1.) 0 deg C, 1 h, 2.) 25 deg C, 2 h2: 44 percent / CH2Cl2 / 20 h / 25 °C3: 90 percent / aq. H2O2 (30 percent), acetic acid / 1 h / 20 °C4: 100 percent / aq. HI (57 percent) / benzene / 2 h5: 68 percent / Me3SiCl, Zn / tetrahydrofuran / Heating