1: 95 percent / glacial acetic acid, DDQ / diethyl ether / 1.) 0 deg C, 1 h, 2.) 25 deg C, 2 h 2: 44 percent / CH2Cl2 / 20 h / 25 °C 3: 90 percent / aq. H2O2 (30 percent), acetic acid / 1 h / 20 °C 4: 100 percent / aq. HI (57 percent) / benzene / 2 h 5: 68 percent / Me3SiCl, Zn / tetrahydrofuran / Heating 6: 90 percent / sodium hydride / tetrahydrofuran / 4 h / Ambient temperature 7: 100 percent / toluene-4-sulphonic acid / benzene / 0.03 h / Heating View Scheme

1: 95 percent / DDQ 2: 1.) PhSeCl; 2.) 30percent H2O2-AcOH / 1.) CH2Cl2, RT, 20 h 3: 57percent HI 4: 30 percent / Mg / tetrahydrofuran / 10 °C 5: p-TSA / benzene / 0.03 h / Heating View Scheme

With  acetic acid; 2,3-dicyano-5,6-dichloro-p-benzoquinone in  diethyl ether  1.) 0 deg C, 1 h, 2.) 25 deg C, 2 h;   

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