trifluoroacetic acid T=0°C; 2 h;

hydrogenchloride T=85°C; 16 h; Inert atmosphere;

1.1: 98 percent / Et3N / tetrahydrofuran / -15 - 20 °C 2.1: n-BuLi / tetrahydrofuran / 1 h / 0 °C 2.2: 50 percent / tetrahydrofuran / 1 h 3.1: 340 mg / trifluoroacetic acid / 0.67 h View Scheme

1.1: sodium / dioxane / 15 h / Heating 1.2: 93 percent / dioxane; tetrahydrofuran / 19 h / 20 °C 2.1: trifluoroacetic acid / 2 h / 0 °C 2.2: 90 percent / aq. ammonia / CHCl3 / 0.17 h / 20 °C View Scheme

1: With lithium in tetrahydrofuran 2: With hydrogenchloride T=100°C; 17 h;

1.1: n-BuLi / tetrahydrofuran / 1 h / 0 °C 1.2: 50 percent / tetrahydrofuran / 1 h 2.1: 340 mg / trifluoroacetic acid / 0.67 h View Scheme

1: tetrahydrofuran / 3 h 2: hydrogenchloride / 16 h / 85 °C / |Inert atmosphere View Scheme

1: tetrahydrofuran / 3 h 2: hydrogenchloride / 16 h / 85 °C / |Inert atmosphere View Scheme

1.1: 82 percent / borane-tetrahydrofuran complex / tetrahydrofuran / 3 h / 0 - 20 °C 2.1: 92 percent / pyridine / CH2Cl2 / 4 h / 0 °C 3.1: sodium / dioxane / 15 h / Heating 3.2: 93 percent / dioxane; tetrahydrofuran / 19 h / 20 °C 4.1: trifluoroacetic acid / 2 h / 0 °C 4.2: 90 percent / aq. ammonia / CHCl3 / 0.17 h / 20 °C View Scheme

1.1: 94 percent / triethylamine / CH2Cl2 / 2.5 h / 0 °C 2.1: 82 percent / borane-tetrahydrofuran complex / tetrahydrofuran / 3 h / 0 - 20 °C 3.1: 92 percent / pyridine / CH2Cl2 / 4 h / 0 °C 4.1: sodium / dioxane / 15 h / Heating 4.2: 93 percent / dioxane; tetrahydrofuran / 19 h / 20 °C 5.1: trifluoroacetic acid / 2 h / 0 °C 5.2: 90 percent / aq. ammonia / CHCl3 / 0.17 h / 20 °C View Scheme