1: 4-(N,N-dimethlyamino)pyridine; triethylamine / dichloromethane / 12 h / 20 °C 2: methanol / 2.5 h / 20 °C 3: 4-(N,N-dimethlyamino)pyridine; triethylamine / dichloromethane / 12 h / 20 °C 4: silica gel / chloroform; ethyl acetate / 0.25 h 5: AZADO; [bis(acetoxy)iodo]benzene / dichloromethane / 4 h / 20 °C 6: hydrogen fluoride / water; acetonitrile / 1.5 h / 20 °C 7: pyridine; dichlorotriphenylphosphorane / acetonitrile / 2 h / 20 °C View Scheme