1: copper dichloride; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride / N,N-dimethyl-formamide / 22 h / 0 - 20 °C 2: sodium hydroxide; water / tetrahydrofuran / 18 h / 20 °C View Scheme

1: benzotriazol-1-ol; diisopropyl-carbodiimide; copper dichloride / N,N-dimethyl-formamide / 5 h / 0 - 20 °C 2: sodium hydroxide; water / tetrahydrofuran / 18 h / 20 °C 3: benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine / dichloromethane / 6 h / 20 °C / |Cooling with ice 4: sodium hydrogencarbonate; potassium bromide; 2,2,6,6-tetramethyl-1-piperidinyloxy, free radical; sodium hypochlorite / dichloromethane / 20 h / 20 °C / |Cooling with ice View Scheme