1: 68 percent / Ba(OH)2*8H2O / methanol; H2O / 4 h / Ambient temperature 2: 56 percent / pyridine / Ambient temperature 3: 94 percent / TsOH / tetrahydrofuran; CH2Cl2 / 2 h / Ambient temperature 4: 96 percent / Ba(OH)2*8H2O / methanol / 1.5 h / Heating 5: 81 percent / Jones reagent / acetone / 0.5 h 6: 73 percent / aq.acetic acid / 15 h / Ambient temperature View Scheme

barium dihydroxide in methanol; water 4 h; Ambient temperature;