sulfuric acid in ethylene glycol dimethyl ether 72 h; Heating;

1: 68 percent / pyridinium tosylate / CH2Cl2 / 6 h / Ambient temperature 2: 63 percent / t-BuOK / 2-methyl-propan-2-ol / 8 h 3: NaOMe, TiCl3, aq. CH3COONH4 / methanol; tetrahydrofuran / 1 h 4: pyridine / tetrahydrofuran / 3.5 h 5: t-BuOK / benzene; 2-methyl-propan-2-ol / 2 h / Ambient temperature 6: 6 M HCl, glac. AcOH, O2 / 5 h / Heating View Scheme

1: 63 percent / t-BuOK / 2-methyl-propan-2-ol / 8 h 2: NaOMe, TiCl3, aq. CH3COONH4 / methanol; tetrahydrofuran / 1 h 3: pyridine / tetrahydrofuran / 3.5 h 4: t-BuOK / benzene; 2-methyl-propan-2-ol / 2 h / Ambient temperature 5: 6 M HCl, glac. AcOH, O2 / 5 h / Heating View Scheme

hydrogenchloride; oxygen; acetic acid 5 h; Heating; Yield given;