1.1: diisobutylaluminium hydride 2.1: sec.-butyllithium / tetrahydrofuran; cyclohexane / 1 h / -78 °C / |Inert atmosphere 2.2: -78 - 20 °C / |Inert atmosphere 3.1: tetrahydrofuran / 20 °C / |Inert atmosphere 4.1: NaBO3*4H2O / tetrahydrofuran; water / 2 h / 20 °C / |Inert atmosphere View Scheme