1: 75 percent / trifluoroacetic acid, H2O, methanol / 12 h 2: 1.) O3, 2.) dimethyl sulfide / 1.) CH3OH, -78 deg. C, 20 min. ; 2.) CH3OH, rt View Scheme

1: 96 percent / trifluoroacetic acid / H2O; methanol / 14 h / Ambient temperature 2: 1) O3; 2) triphenylphosphine / 1) MeOH, -78 deg C, 20 min; 2) MeOH, CH2Cl2, -78 deg C, 90 min 3: 65 mg / ethanol / 5 h / 5 °C View Scheme

1: 1) NaH / tetrahydrofuran; dimethylsulfoxide / 1) reflux, 3 hr, 2) reflux, 2 hr 2: 2N H2SO4 / dioxane / 2 h / 110 °C 3: Pb(OAc)4 / benzene / 0.17 h / 22 °C 4: LiAlH4 / diethyl ether / 3 h / 22 °C 5: H2, 1percent HCl / Pd / methanol / 22 °C / 1520 Torr View Scheme