1.1: potassium carbonate / acetone / 0.08 h / |Inert atmosphere 1.2: 5 h / |Reflux 2.1: Lipase AK "AMANO" / hexane / 48 h / |Inert atmosphere 3.1: potassium hydroxide; water / methanol / |Reflux 4.1: hydrogen fluoride / acetonitrile; water / -20 - 20 °C View Scheme