in toluene T=121°C; 12 h;

1: TBAF / tetrahydrofuran / 1 h / 0 °C 2: pyridine; PBr3 / CH2Cl2 / 0.17 h / 0 °C 3: 1.0 g / toluene / 12 h / 121 °C View Scheme

1.1: NaH / tetrahydrofuran / 0.5 h / 0 °C 1.2: 2.7 g / tetrahydrofuran / 0 - 23 °C 2.1: TBAF / tetrahydrofuran / 1 h / 0 °C 3.1: pyridine; PBr3 / CH2Cl2 / 0.17 h / 0 °C 4.1: 1.0 g / toluene / 12 h / 121 °C View Scheme

1.1: MnO2 / CH2Cl2 / 5 h / 20 °C 2.1: NaH / tetrahydrofuran / 0.5 h / 0 °C 2.2: 2.7 g / tetrahydrofuran / 0 - 23 °C 3.1: TBAF / tetrahydrofuran / 1 h / 0 °C 4.1: pyridine; PBr3 / CH2Cl2 / 0.17 h / 0 °C 5.1: 1.0 g / toluene / 12 h / 121 °C View Scheme

1.1: hexane / -78 °C / |Inert atmosphere 2.1: diisobutylaluminium hydride; zirconocene dichloride / tetrahydrofuran; hexane / 0.5 h / 0 - 23 °C / |Inert atmosphere 2.2: 4 h / 23 °C / |Inert atmosphere 3.1: pyridine; phosphorus tribromide / dichloromethane / 0.17 h / 0 °C / |Inert atmosphere 4.1: toluene / 12 h / 110 °C / |Inert atmosphere View Scheme