1: PCC / CH2Cl2 / 4 h / Ambient temperature 2: LiBH4, N,N'-dibenzoyl-D-cystine / 2-methyl-propan-2-ol; tetrahydrofuran / 5 h / -78 °C 3: 5 percent / HN3, DEAD, PPh3 / benzene / 3 h / 0 deg C to RT View Scheme

1: PCC / CH2Cl2 / 4 h / Ambient temperature 2: LiBH4, N,N'-dibenzoyl-D-cystine / 2-methyl-propan-2-ol; tetrahydrofuran / 5 h / -78 °C 3: 80 percent / HN3, DEAD, PPh3 / benzene / 3 h / 0 deg C to RT 4: H2 / Pd-C / methanol / 760 Torr / Ambient temperature 5: tetrahydrofuran / 6 h / Ambient temperature 6: imidazole / CH2Cl2 / 3 h / Ambient temperature 7: CF3COOH / CH2Cl2 / 3 h / 0 °C 8: DCC, HOBT / CH2Cl2 / 6 h / 0 deg C to RT 9: TBS-OTf, 2,6-lutidine / CH2Cl2 / 3 h / Ambient temperature 10: DCC, HOBT / CH2Cl2 / 5 h / -5 - 0 °C 11: HF-pyridine / CH2Cl2 / 4 h / Ambient temperature 12: LiOH / tetrahydrofuran; methanol; H2O / 3 h / Ambient temperature 13: DCC, DMAP, DMAP*TFA / CHCl3 / 16 h / Heating View Scheme