1.1: boron trifluoride diethyl etherate; triethylsilane / dichloromethane / 0.08 h / 0 - 20 °C / |Inert atmosphere 2.1: iodine; sodium tetrahydroborate / tetrahydrofuran / 3 h / 0 - 20 °C / |Inert atmosphere 2.2: 0 °C 3.1: tetrabutylammomium bromide; potassium permanganate; acetic acid / dichloromethane; water / 24 h / |Reflux View Scheme