1.1: sodium hydride / tetrahydrofuran; mineral oil / 2.5 h / 0 - 23 °C / |Inert atmosphere 1.2: 12 h / 23 °C / |Inert atmosphere 2.1: 2,2,6,6-tetramethyl-1-piperidinyloxy, free radical; sodium hydrogencarbonate; potassium bromide; NaClO / dichloromethane; water / 0.25 h / 0 °C / |Inert atmosphere 3.1: tetrahydrofuran; diethyl ether / 0.17 h / -78 °C / |Inert atmosphere View Scheme