1: diisobutylaluminium hydride / tetrahydrofuran; toluene / 2 h / 20 °C / Inert atmosphere 2: sodium hydride / N,N-dimethyl-formamide; mineral oil / 2 h / 20 °C / Inert atmosphere 3: trifluoroacetic acid / dichloromethane / 4 h / 0 °C / Inert atmosphere View Scheme

1.1: diisobutylaluminium hydride / tetrahydrofuran; toluene / 2 h / 20 °C / Inert atmosphere 2.1: sodium hydride / N,N-dimethyl-formamide; mineral oil / 20 °C / Inert atmosphere 3.1: trifluoroacetic acid / dichloromethane / 20 °C / Inert atmosphere 3.2: Saturated solution View Scheme