1.1: triethylamine / dichloromethane / -10 °C 2.1: tetra(n-butyl)ammonium hydrogensulfate; sodium azide / N,N-dimethyl-formamide / 36 h / 90 °C 3.1: triethylamine; hydrogen / palladium 10 on activated carbon / ethanol; water / 16 h / 3102.97 Torr 4.1: potassium hydroxide / water; tetrahydrofuran; methanol / 10 h / 0 °C 4.2: 10 h / 0 - 20 °C 5.1: triethylamine; 2-hydroxy-pyridine / 48 h / 90 °C 6.1: trifluoroacetic acid / dichloromethane / 3 h / 20 °C View Scheme

1: palladium on activated charcoal; hydrogen / methanol / 60 h / 2844.39 Torr 2: triethylamine / dichloromethane / 1.17 h / 20 °C 3: sodium azide / N,N-dimethyl-formamide / 25 h / 80 °C 4: propionic acid / 2 h / 110 °C 5: triethylamine / dichloromethane / 0.33 h / 20 °C 6: triethylamine / 1,2-dichloro-ethane / 21 h / 80 °C 7: water; dihydrogen peroxide; lithium hydroxide hydrate / tetrahydrofuran / 144 h / 55 °C View Scheme