triphenylphosphine; diethylazodicarboxylate in tetrahydrofuran

1: NaBH4 / methanol / 1 h / -4 °C 2: methanesulfonyl chloride, triethylamine / CH2Cl2 / -20 deg C to r.t. 3: 95 percent / LiAlH4 / tetrahydrofuran / 1 h 4: 1) diisopropylamine/n-BuLi / 1) THF, hexane, HMPA, -20 deg C, 2 h 2) -78 deg C, 1 h 5: 70 percent / HgCl2, CaCO3 / acetonitrile; H2O / 1 h / 50 °C View Scheme

1: NaBH4 / methanol / 1 h / -4 °C 2: methanesulfonyl chloride, triethylamine / CH2Cl2 / -20 deg C to r.t. View Scheme

1: NaBH4 / methanol / 1 h / -4 °C 2: methanesulfonyl chloride, triethylamine / CH2Cl2 / -20 deg C to r.t. 3: 95 percent / LiAlH4 / tetrahydrofuran / 1 h 4: 1) diisopropylamine/n-BuLi / 1) THF, hexane, HMPA, -20 deg C, 2 h 2) -78 deg C, 1 h View Scheme