1: 96 percent / pyridine / CH2Cl2 / 0.5 h / 0 °C 2: 89 percent / tetrahydrofuran / 3 h / 80 °C 3: 98 percent / NaOMe / methanol / 6 h / Ambient temperature 4: H2 / Raney nickel / ethyl acetate / 18 h / Ambient temperature 5: Na, NH3 / tetrahydrofuran / 1.5 h / -40 °C View Scheme