1: pyridine / CH2Cl2 2: 19 percent / CH3COOK / 6 h / 120 °C 3: 93 percent / 1 N KOH / ethanol / 24 h / Ambient temperature 4: 78 percent / borontrifluoride / 0.33 h / 80 °C 5: Na2Cr2O7*2H2O, conc. AcOH, conc. H2SO4 / H2O / 2 h / Ambient temperature View Scheme

1: pyridine / CH2Cl2 2: 19 percent / CH3COOK / 6 h / 120 °C 3: 93 percent / 1 N KOH / ethanol / 24 h / Ambient temperature 4: 78 percent / borontrifluoride / 0.33 h / 80 °C 5: Na2Cr2O7*2H2O, conc. AcOH, conc. H2SO4 / H2O / 2 h / Ambient temperature 6: 37 percent / NaBH4 / toluene; methanol / 4 h / Ambient temperature View Scheme

1: pyridine / CH2Cl2 2: 19 percent / CH3COOK / 6 h / 120 °C 3: 93 percent / 1 N KOH / ethanol / 24 h / Ambient temperature 4: 78 percent / borontrifluoride / 0.33 h / 80 °C 5: Na2Cr2O7*2H2O, conc. AcOH, conc. H2SO4 / H2O / 2 h / Ambient temperature 6: 37 percent / NaBH4 / toluene; methanol / 4 h / Ambient temperature 7: 1 N KOH / methanol / 5 h / 80 °C View Scheme