1.1: TFAA; 2,4,6-collidine / acetonitrile / 0.17 h / 0 °C 2.1: aq. K2CO3 / acetonitrile / 0.5 h / 20 °C 2.2: aq. NaBH4 / acetonitrile / 1 h / 20 °C 3.1: 81 percent / 4 Angstroem molecular sieves; Celite; PCC / CH2Cl2 / 3 h / 20 °C 4.1: 96 percent / n-BuLi / tetrahydrofuran; hexane / 0.5 h / 0 °C 5.1: 93 percent / H2 / Pd/Al2O3 / tetrahydrofuran / 4 h / 20 °C / 37503 Torr View Scheme