1: With hydrogen bromide T=20 - 70°C; 0.166667 h; 2: With dihydrogen peroxide in water T=60 - 70°C; 3 h;

1: 56 percent / ZnCl2 / benzene / 32 h / Heating 2: 86 percent / SnCl2*2H2O / ethanol / 1.) reflux, 0.5 h, 2.) room temp., 13 h 3: 1.) NaNO2, 48percent HBF4, 2.) 50percent aq. H3PO2 / 1.) H2O, 0 deg C, 2.5 h, 2.) CHCl3, 24 h, room temp. 4: 69 percent / conc. HCl / ethanol / 75 h / Heating 5: 1.) conc. HCl, NaNO2, 2.) KI / 1.) H2O, 0-5 deg C, 2.) room temp., 22 h 6: 58 percent / powdered Mg / tetrahydrofuran / 1 h / Heating View Scheme

1: 56 percent / ZnCl2 / benzene / 32 h / Heating 2: 86 percent / SnCl2*2H2O / ethanol / 1.) reflux, 0.5 h, 2.) room temp., 13 h 3: 1.) NaNO2, 48percent HBF4, 2.) 50percent aq. H3PO2 / 1.) H2O, 0 deg C, 2.5 h, 2.) CHCl3, 24 h, room temp. 4: 69 percent / conc. HCl / ethanol / 75 h / Heating 5: 1.) conc. HCl, NaNO2, 2.) KI / 1.) H2O, 0-5 deg C, 2.) room temp., 22 h 6: 58 percent / powdered Mg / tetrahydrofuran / 1 h / Heating 7: 1.) diborane, 2.) 3 N aq. NaOH, 30percent H2O2 / 1.) THF, 0 deg C, then 16 h room temp., 2.) 4 h, room temp. 8: 92 percent / benzoquinone, (t-BuO)3Al / benzene / 40 h / Heating View Scheme

1: 56 percent / ZnCl2 / benzene / 32 h / Heating 2: 86 percent / SnCl2*2H2O / ethanol / 1.) reflux, 0.5 h, 2.) room temp., 13 h 3: 1.) NaNO2, 48percent HBF4, 2.) 50percent aq. H3PO2 / 1.) H2O, 0 deg C, 2.5 h, 2.) CHCl3, 24 h, room temp. 4: 69 percent / conc. HCl / ethanol / 75 h / Heating 5: 1.) conc. HCl, NaNO2, 2.) KI / 1.) H2O, 0-5 deg C, 2.) room temp., 22 h 6: 58 percent / powdered Mg / tetrahydrofuran / 1 h / Heating 7: 1.) diborane, 2.) 3 N aq. NaOH, 30percent H2O2 / 1.) THF, 0 deg C, then 16 h room temp., 2.) 4 h, room temp. 8: 56 percent / benzoquinone, (t-BuO)3Al / benzene / 40 h / Heating View Scheme

1: 56 percent / ZnCl2 / benzene / 32 h / Heating 2: 86 percent / SnCl2*2H2O / ethanol / 1.) reflux, 0.5 h, 2.) room temp., 13 h 3: 1.) NaNO2, 48percent HBF4, 2.) 50percent aq. H3PO2 / 1.) H2O, 0 deg C, 2.5 h, 2.) CHCl3, 24 h, room temp. 4: 69 percent / conc. HCl / ethanol / 75 h / Heating View Scheme