1: 47 percent / NaBH4 / ethanol / 0.5 h / 0 °C 2: 57 percent / Et3N / CH2Cl2 / 0.5 h / 20 °C 3: 90 percent / DBU / toluene / 48 h / Heating 4: 4.93 g / aq. NaOH / ethanol / 15 h / 20 °C 5: Et3N / acetone / 0.5 h / 20 °C 6: aq. NaN3 / acetone / 1 h / 0 °C 7: benzene / 3 h / Heating 8: 2.05 g / aq. HCl / tetrahydrofuran View Scheme

1: 47 percent / NaBH4 / ethanol / 0.5 h / 0 °C 2: 57 percent / Et3N / CH2Cl2 / 0.5 h / 20 °C 3: 90 percent / DBU / toluene / 48 h / Heating View Scheme