1: pyridinium p-toluenesulfonate / toluene / 2 h / 90 °C / |Inert atmosphere 2: lithium hydroxide hydrate / methanol; tetrahydrofuran / 0.5 h / 20 °C / |Inert atmosphere 3: boron tribromide / dichloromethane / -78 - 20 °C / |Inert atmosphere View Scheme

<b>Multi-step reaction with 7 steps<br /> </b>1: AlCl₃, aluminium chloride / dichloromethane / 2 h / 0 - 20 &deg;C / |Inert atmosphere<br />2: sodium hydride / paraffin oil / 90 &deg;C / |Inert atmosphere<br />3: sodium tetrahydroborate / methanol / 1 h / 0 - 20 &deg;C / |Inert atmosphere<br />4: pyridinium p-toluenesulfonate / toluene / |Inert atmosphere; |Reflux; |Dean-Stark<br />5: diisobutylaluminium hydride / dichloromethane; toluene / 3 h / -78 &deg;C / |Inert atmosphere<br />6: triphenylphosphine; diethylazodicarboxylate / tetrahydrofuran / 1.5 h / -78 - 20 &deg;C / |Inert atmosphere<br />7: AD-mix-βreg;; methanesulfonamide; osmium(VIII) oxide / dichloromethane; #tert!-butyl alcohol; water / 72 h / 20 &deg;C / |Inert atmosphere<br /> <br /> &nbsp;

<b>Multi-step reaction with 4 steps<br /> </b>1: pyridinium p-toluenesulfonate / toluene / |Inert atmosphere; |Reflux; |Dean-Stark<br />2: diisobutylaluminium hydride / dichloromethane; toluene / 3 h / -78 &deg;C / |Inert atmosphere<br />3: triphenylphosphine; diethylazodicarboxylate / tetrahydrofuran / 1.5 h / -78 - 20 &deg;C / |Inert atmosphere<br />4: AD-mix-βreg;; methanesulfonamide; osmium(VIII) oxide / dichloromethane; #tert!-butyl alcohol; water / 72 h / 20 &deg;C / |Inert atmosphere<br /> <br /> &nbsp;