1.1: lithium aluminium tetrahydride / diethyl ether / 2.5 h / |Inert atmosphere 2.1: toluene-4-sulfonic acid; sodium sulfate / acetone / 72 h / 40 °C 3.1: n-butyllithium / tetrahydrofuran / 0.75 h / -78 °C / |Inert atmosphere 3.2: 1 h / -78 °C / |Inert atmosphere 4.1: sodium tetrahydroborate / ethanol / 0.5 h / 0 °C 5.1: hydrogenchloride / tetrahydrofuran / 20 °C 6.1: sodium tetrahydroborate / ethanol / 0.5 h View Scheme

1.1: toluene-4-sulfonic acid; sodium sulfate / acetone / 72 h / 40 °C 2.1: n-butyllithium / tetrahydrofuran / 0.75 h / -78 °C / |Inert atmosphere 2.2: 1 h / -78 °C / |Inert atmosphere 3.1: sodium tetrahydroborate / ethanol / 0.5 h / 0 °C 4.1: hydrogenchloride / tetrahydrofuran / 20 °C 5.1: sodium tetrahydroborate / ethanol / 0.5 h View Scheme

1.1: n-butyllithium / tetrahydrofuran / 0.75 h / -78 °C / |Inert atmosphere 1.2: 1 h / -78 °C / |Inert atmosphere 2.1: sodium tetrahydroborate / ethanol / 0.5 h / 0 °C 3.1: hydrogenchloride / tetrahydrofuran / 20 °C 4.1: sodium tetrahydroborate / ethanol / 0.5 h View Scheme

1: sodium tetrahydroborate / ethanol / 0.5 h / 0 °C 2: hydrogenchloride / tetrahydrofuran / 20 °C 3: sodium tetrahydroborate / ethanol / 0.5 h View Scheme

1: hydrogenchloride / tetrahydrofuran / 20 °C 2: sodium tetrahydroborate / ethanol / 0.5 h View Scheme

potassium carbonate in acetone 12 h; Reflux;

sodium hydroxide Heating;

sodium hydroxide Heating;