1: tetrabutyl ammonium fluoride / tetrahydrofuran / 2 h / 20 °C 2: 2,2,6,6-tetramethyl-1-piperidinyloxy, free radical; sodium hypochlorite; sodium bromide; sodium hydrogencarbonate / dichloromethane / 2 h / 0 °C View Scheme

1: tetrabutyl ammonium fluoride / tetrahydrofuran / 2 h / 20 °C 2: 2,2,6,6-tetramethyl-1-piperidinyloxy, free radical; sodium hypochlorite; sodium bromide; sodium hydrogencarbonate / dichloromethane / 2 h / 0 °C 3: 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; benzotriazol-1-ol; triethylamine / acetonitrile / 24 h / 0 - 20 °C 4: hydrogenchloride / water; methanol View Scheme