1: DCC / CH2Cl2 / 1 h / 0 °C 2: 87 percent / HBr / acetic acid / 0.5 h 3: 52 percent / pyridine / 12 h 4: 77 percent / NaH / dimethylformamide / 0.75 h / 0 °C 5: 39 percent / H2O / 0.17 h / Heating View Scheme

1: DCC / CH2Cl2 / 1 h / 0 °C 2: 87 percent / HBr / acetic acid / 0.5 h 3: 52 percent / pyridine / 12 h 4: 53 percent / PCl5 / CH2Cl2 / 0.08 h 5: 54 percent / Et3N / CH2Cl2 / 12 h 6: 50 percent / potassium t-butoxide / tetrahydrofuran / 1 h / 0 °C View Scheme

1: DCC / CH2Cl2 / 1 h / 0 °C 2: 87 percent / HBr / acetic acid / 0.5 h 3: 52 percent / pyridine / 12 h 4: 53 percent / PCl5 / CH2Cl2 / 0.08 h 5: 59 percent / Et3N / CH2Cl2 / 12 h 6: 22 percent / potassium t-butoxide / tetrahydrofuran / 1 h / 0 °C View Scheme

1: DCC / CH2Cl2 / 1 h / 0 °C 2: 87 percent / HBr / acetic acid / 0.5 h 3: 52 percent / pyridine / 12 h 4: 53 percent / PCl5 / CH2Cl2 / 0.08 h 5: 59 percent / Et3N / CH2Cl2 / 12 h 6: 22 percent / potassium t-butoxide / tetrahydrofuran / 1 h / 0 °C 7: 40 percent / tetrahydrofuran / 1 h View Scheme

1: DCC / CH2Cl2 / 1 h / 0 °C 2: 87 percent / HBr / acetic acid / 0.5 h 3: 92 percent / Et3N / CH2Cl2 / 18 h 4: 65 percent / NaH / dimethylformamide / 1 h / 0 °C 5: 46 percent / 1M hydrochloric acid / acetone / 1 h View Scheme

1: DCC / CH2Cl2 / 1 h / 0 °C 2: 87 percent / HBr / acetic acid / 0.5 h 3: 52 percent / pyridine / 12 h 4: 63 percent / 1M hydrochloric acid / H2O / 3 h / Heating View Scheme

1: DCC / CH2Cl2 / 1 h / 0 °C 2: 87 percent / HBr / acetic acid / 0.5 h 3: 52 percent / pyridine / 12 h 4: 77 percent / NaH / dimethylformamide / 0.75 h / 0 °C View Scheme