1: Al(i-PrO)3 / 0.75 h / 130 - 140 °C 2: 550 mg / SnCl4 / CH2Cl2; nitromethane / 4 h / -78 - 20 °C 3: 81 percent / NMO; H2O / OsO4 / tetrahydrofuran; 2-methyl-propan-2-ol / 24 h / 20 °C 4: NCS; Me2S; Et3N / CH2Cl2 / 2.5 h / -40 - 20 °C 5: 24 mg / TfOH / CH2Cl2 / 24 h / 0 °C 6: 75 percent / aluminum hydride / tetrahydrofuran / 2.5 h / 0 °C View Scheme