1: sodium hydroxide / toluene; water / 4.95 h / 20 - 47 °C / Inert atmosphere; Industry scale 2: isopropyl alcohol; water / 25 °C / Reflux; Inert atmosphere; Industry scale; Resolution of racemate 3: sodium hydroxide / toluene; water / 40 - 47 °C / Industry scale; Inert atmosphere View Scheme