1: n-butyllithium / hexane; tetrahydrofuran / 1 h / -70 - -60 °C 2: Na2HPO4, 5percent sodium amalgam / methanol / 0 deg C, 15 h, then RT, 3 h 3: PPTS / aq. ethanol / 1 h / 50 °C 4: LiAlH4 / tetrahydrofuran / 1.5 h / Heating 5: diethyl ether; tetrahydrofuran / 0.05 h / Irradiation 6: ethanol / 1 h / Heating View Scheme

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

pyridinium p-toluenesulfonate in dichloromethane

1: pyridine / 2 h / Ambient temperature 2: potassium t-butoxide / dimethylformamide / 4 h / Ambient temperature 3: WO3, 50percent NaOH, 30percent H2O2 / H2O; ethanol / 0.67 h / 60 - 75 °C 4: 92 percent / PPTS / CH2Cl2 / 4 h / Ambient temperature 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

1: potassium t-butoxide / dimethylformamide / 4 h / Ambient temperature 2: WO3, 50percent NaOH, 30percent H2O2 / H2O; ethanol / 0.67 h / 60 - 75 °C 3: 92 percent / PPTS / CH2Cl2 / 4 h / Ambient temperature View Scheme

2: 90 percent / pyridine 3: 91 percent / potassium tert-butylate / dimethylformamide 4: 99 percent / Na2WO4, H2O2 / 70 °C 5: 95 percent / pyridinium p-toluenesulphonate / CH2Cl2 View Scheme

1: 92 percent / NaH / dimethylsulfoxide / Ambient temperature 2: 93 percent / diethyl ether / -20 °C 4: 90 percent / pyridine 5: 91 percent / potassium tert-butylate / dimethylformamide 6: 99 percent / Na2WO4, H2O2 / 70 °C 7: 95 percent / pyridinium p-toluenesulphonate / CH2Cl2 View Scheme

1: 93 percent / diethyl ether / -20 °C 3: 90 percent / pyridine 4: 91 percent / potassium tert-butylate / dimethylformamide 5: 99 percent / Na2WO4, H2O2 / 70 °C 6: 95 percent / pyridinium p-toluenesulphonate / CH2Cl2 View Scheme

1: 25 percent / tert-butylhydroperoxide, titanium(IV) isopropoxyde, D-(-)-dibutyl tartarate / CH2Cl2 / -20 °C 2: 92 percent / NaH / dimethylsulfoxide / Ambient temperature 3: 93 percent / diethyl ether / -20 °C 5: 90 percent / pyridine 6: 91 percent / potassium tert-butylate / dimethylformamide 7: 99 percent / Na2WO4, H2O2 / 70 °C 8: 95 percent / pyridinium p-toluenesulphonate / CH2Cl2 View Scheme