1.1: 1-hydroxy-pyrrolidine-2,5-dione; dicyclohexyl-carbodiimide / ethyl acetate / 8 h / 0 - 20 °C 1.2: 0.08 h 2.1: triphenylphosphine; diethylazodicarboxylate / dichloromethane / 10 h / 0 - 20 °C / |Inert atmosphere 3.1: tert-butylmagnesium bromide; copper(I) bromide dimethylsulfide complex / tetrahydrofuran / 0.25 h / -20 - -5 °C / |Inert atmosphere 3.2: 0.08 h 4.1: tetrabutyl ammonium fluoride / tetrahydrofuran / 2 h / 20 °C 5.1: 2,2,6,6-tetramethyl-1-piperidinyloxy, free radical; sodium hypochlorite; sodium bromide; sodium hydrogencarbonate / dichloromethane / 2 h / 0 °C View Scheme