1: 48 percent / diethyl ether / 1.) 0 deg C, 0.5 h, 2.) r.t., overnight 2: 85 percent / Et3N / CH2Cl2 / 1.) 0 deg C, 2 h, 2.) r.t., 4 h 3: 77 percent / 1 N HCl / tetrahydrofuran / 12 h / 60 °C 4: 80 percent / Et3N / tetrahydrofuran / 3 h / -70 °C 5: 75 percent / pyridine / 12 h / 70 - 80 °C 6: 90 percent / NaN3 / dimethylformamide / 36 h / 100 °C 7: 98 percent / NaOMe / methanol / 2 h / Ambient temperature View Scheme

lithium aluminium tetrahydride; sodium hexamethyldisilazane in tetrahydrofuran T=20°C; 8 h;