1.1: sulfuric acid; water / diethyl ether / 2 h / 20 °C / pH 2.5 2.1: lithium aluminium tetrahydride / diethyl ether / -10 - 20 °C 3.1: hydrogenchloride; water / diethyl ether / 4 h / 20 °C 4.1: potassium tert-butylate / tetrahydrofuran / 0.5 h / 20 °C 4.2: 0 - 20 °C View Scheme

1: sulfuric acid; water / diethyl ether / 2 h / 20 °C / pH 2.5 2: lithium aluminium tetrahydride / diethyl ether / -10 - 20 °C 3: hydrogenchloride; water / diethyl ether / 4 h / 20 °C View Scheme