1.1: sodium tetrahydroborate; boron trifluoride diethyl etherate / tetrahydrofuran / 31 - 35 °C 1.2: 30 - 65 °C 2.1: isopropyl alcohol; water / Reflux 3.1: sodium carbonate / dichloromethane; water 3.2: 14 - 20 °C 4.1: hydrogenchloride; sodium tetrahydroborate / water / 32 - 38 °C 4.2: Reflux 5.1: sodium hydroxide; sodium carbonate / dichloromethane; water 5.2: Raney nickel View Scheme

1.1: sodium tetrahydroborate; boron trifluoride diethyl etherate / tetrahydrofuran / 31 - 35 °C 1.2: 30 - 65 °C 2.1: isopropyl alcohol; water / Reflux 3.1: sodium carbonate / dichloromethane; water 3.2: 14 - 20 °C 4.1: hydrogenchloride; sodium tetrahydroborate / water / 32 - 38 °C 4.2: Reflux 5.1: sodium hydroxide; sodium carbonate / dichloromethane; water 5.2: Raney nickel 6.1: triethylamine / dichloromethane / 0.75 h / 0 - 20 °C View Scheme

<b>Multi-step reaction with 2 steps<br /> </b>1.1: potassium hydroxide; water / methanol / Inert atmosphere; Reflux<br />1.2: pH 1 - 2<br />2.1: toluene / 0 - 10 &deg;C<br />2.2: 50 - 60 &deg;C<br /> <br /> &nbsp;

<b>Multi-step reaction with 4 steps<br /> </b>1.1: sulfuric acid / 120 - 125 &deg;C / Inert atmosphere<br />2.1: potassium carbonate / acetone / Reflux<br />3.1: potassium hydroxide; water / methanol / Inert atmosphere; Reflux<br />3.2: pH 1 - 2<br />4.1: toluene / 0 - 10 &deg;C<br />4.2: 50 - 60 &deg;C<br /> <br /> &nbsp;

<b>Multi-step reaction with 4 steps<br /> </b>1.1: sulfuric acid / 120 - 125 &deg;C / Inert atmosphere<br />2.1: potassium carbonate / acetone / Reflux<br />3.1: potassium hydroxide; water / methanol / Inert atmosphere; Reflux<br />3.2: pH 1 - 2<br />4.1: toluene / 0 - 10 &deg;C<br />4.2: 50 - 60 &deg;C<br /> <br /> &nbsp;