1: 1.) KH, ethanol, 2.) diethyl carbonate / 1.) toluene, reflux, 10 min, 2.) toluene, reflux, 3 h 2: 1.) potassium tert-butoxide / 1.) DME, -78 deg C, 5 min, 2.) DME, a.) -78 deg C, 1.5 h, b.) RT, overnight 3: 100 percent / H2 / Raney nickel / acetic acid / 6 h / 45 °C / 2585.7 Torr 4: NaNO2 / acetic anhydride; acetic acid / 2 h / 0 °C 5: CCl4 / Heating 6: 88 percent / H2SO4 / 1,2-dimethoxy-ethane / 24 h / 50 °C 7: 2.) p-toluenesulfonic acid / 1.) toluene, ref;ux, 30 min, 2.) toluene, reflux, 3 h 8: 41 percent / O2, cupric chloride, dimethylamine / dimethylformamide; H2O View Scheme

toluene-4-sulfonic acid in toluene 20 h; Heating;

1: 1.) K2CO3 / 1.) DMF, 45 deg C, 2.) DMF, 45 deg C, 40 h 2: 89 percent / conc. HCl / acetic acid / 2 h / Heating 3: 93 percent / p-toluenesulfonic acid / toluene / 20 h / Heating View Scheme