1.1: sodium hydroxide / ethanol; water / 3 h / Reflux 1.2: 1 h / 160 °C / Inert atmosphere 2.1: lithium aluminium tetrahydride / tetrahydrofuran / 5 h / 0 - 20 °C 3.1: triethylamine / dichloromethane / 1 h / 20 °C 4.1: N,N-dimethyl-formamide / 1 h / 100 °C 5.1: hydrazine / ethanol / 3 h / Reflux 6.1: sodium hydroxide / tetrahydrofuran; water / 1 h / 20 °C View Scheme