1: boron tribromide / dichloromethane / 1.5 h / 23 °C / Inert atmosphere 2: sodium hydride / tetrahydrofuran / 14 h / 23 °C / Inert atmosphere 3: CHIRALPAK OJ-H (2 cm x 25 cm) / methanol; carbon dioxide; diethylamine / resolution of racemate; Supercritical conditions View Scheme