1: 80 percent / CrO3, pyridine / CH2Cl2 / 1 h / 14 - 25 °C 2: 42 percent / K2CO3, 18-crown-6 / benzene / 0.67 h / 56 °C 3: 97 percent / NaBH4, CeCl3*7H2O / methanol / 0.17 h / 0 - 5 °C 4: 100 percent / Et3N / CH2Cl2 / 0.17 h / -5 - 0 °C 5: 74 percent / LiN3, P(NMe2)3 / dimethylsulfoxide / Ambient temperature 6: H2 / Lindlar's catalyst / butan-1-ol / 3 h / 760 Torr 7: Et3N / butan-1-ol / 20 h / Heating 8: conc. HCl / 42 h / Ambient temperature 9: 70 percent / liquid NH3 / methanol / 18 h / 60 °C 10: 50 percent / 1 M BCl3 / CH2Cl2; hexane / 2.5 h / -75 °C View Scheme