1: boron trichloride / dichloromethane / 22 h / 0 - 20 °C / |Inert atmosphere 2: sodium dithionite; lithium hydroxide hydrate / water; tetrahydrofuran / 9 h / 20 °C / |Inert atmosphere View Scheme

1: pyridinium p-toluenesulfonate / methanol; tetrahydrofuran / 21.5 h / 20 °C / |Inert atmosphere 2: boron trifluoride diethyl etherate / dichloromethane / 2 h / 0 °C / |Inert atmosphere 3: copper(l) iodide; caesium acetate; caesium carbonate / dimethyl sulfoxide / 3 h / 90 °C / |Inert atmosphere; |Glovebox 4: thiophenol / acetonitrile / 4 h / 20 °C / |Inert atmosphere 5: sodium cyanoborohydride / acetic acid / 1 h / 20 °C / |Inert atmosphere 6: 4-(N,N-dimethlyamino)pyridine / acetic acid; dichloromethane / 5 h / 20 °C / |Inert atmosphere 7: boron trichloride / dichloromethane / 22 h / 0 - 20 °C / |Inert atmosphere 8: sodium dithionite; lithium hydroxide hydrate / water; tetrahydrofuran / 9 h / 20 °C / |Inert atmosphere View Scheme