1: 96 percent / H2, NaOAc / 10percent Pd/C / methanol / 18 h 2: 1.) LDA / 1.) THF, hexane, -78 deg C, 30 min, 2.) THF, 30 min 3: DMAP / CH2Cl2 / 2 h / Ambient temperature 4: DBU / toluene / 3 h / 80 °C 5: 58 percent / 3.75 M aq. NaOH / aq. ethanol / 4 h View Scheme

hydrogen; sodium acetate; palladium on activated charcoal in methanol 18 h;

1: 96 percent / H2, NaOAc / 10percent Pd/C / methanol / 18 h 2: 1.) LDA / 1.) THF, hexane, -78 deg C, 30 min, 2.) THF, 30 min 3: DMAP / CH2Cl2 / 2 h / Ambient temperature 4: DBU / toluene / 3 h / 80 °C View Scheme