1: 79 percent / AcOH / tetrahydrofuran / 336 h / 20 °C 2: 56 percent / NaOH / ethanol / 2 h / Heating 3: 56 percent / K2CO3 / methanol / 0.17 h / Heating 4: Et3N / CH2Cl2 / 0.75 h / 0 °C 5: NaCl / dimethylformamide / 0.08 h / 120 °C 6: 99 percent / concd. HCl / 1.5 h / Heating 7: EtOCOCl, Et3N / acetone / 0.17 h / -5 °C 8: aq. NaN3 / acetone / 0.5 h / 0 °C 9: toluene / 1.5 h / Heating 10: 8 N HCl / 0.17 h / Heating 11: methanol / 14 h / 20 °C View Scheme

1: 79 percent / AcOH / tetrahydrofuran / 336 h / 20 °C 2: 56 percent / NaOH / ethanol / 2 h / Heating 3: 57 percent / K2CO3 / methanol / 0.17 h / Heating 4: Et3N / CH2Cl2 / 0.75 h / 0 °C 5: NaCl / dimethylformamide / 0.08 h / 120 °C 6: 73 percent / concd. HCl / 1.5 h / Heating 7: EtOCOCl, Et3N / acetone / 0.17 h / -5 °C 8: aq. NaN3 / acetone / 0.5 h / 0 °C 9: toluene / 1.5 h / Heating 10: 8 N HCl / 0.17 h / Heating 11: 76 percent / methanol / 14 h / 20 °C View Scheme