1: WO3, 50percent NaOH, 30percent H2O2 / H2O; ethanol / 0.67 h / 60 - 75 °C 2: 92 percent / PPTS / CH2Cl2 / 4 h / Ambient temperature 3: n-butyllithium / hexane; tetrahydrofuran / 1 h / -70 - -60 °C 4: Na2HPO4, 5percent sodium amalgam / methanol / 0 deg C, 15 h, then RT, 3 h 5: PPTS / aq. ethanol / 1 h / 50 °C 6: LiAlH4 / tetrahydrofuran / 1.5 h / Heating 7: diethyl ether; tetrahydrofuran / 0.05 h / Irradiation 8: ethanol / 1 h / Heating View Scheme

1: 99 percent / Na2WO4, H2O2 / 70 °C 2: 95 percent / pyridinium p-toluenesulphonate / CH2Cl2 3: 1) lithium diisopropylamide / 1) THF, -78 deg C 4: 52 percent / 5percent Na-Hg, Na2HPO4 / 0 °C 5: 95 percent / 95percent ethanol / pyridinium p-toluenesulphonate / 40 °C 6: irradiation followed by thermal isomerization View Scheme

1: WO3, 50percent NaOH, 30percent H2O2 / H2O; ethanol / 0.67 h / 60 - 75 °C 2: 92 percent / PPTS / CH2Cl2 / 4 h / Ambient temperature View Scheme

sodium tungstate; dihydrogen peroxide T=70°C;

Multi-step reaction with 5 steps 1: 99 percent / Na2WO4, H2O2 / 70 °C2: 95 percent / pyridinium p-toluenesulphonate / CH2Cl2 3: 1) lithium diisopropylamide / 1) THF, -78 deg C4: 52 percent / 5percent Na-Hg, Na2HPO4 / 0 °C5: 95 percent / 95percent ethanol / pyridinium p-toluenesulphonate / 40 °C