1.1: (Me3Si)2NNa / tetrahydrofuran / 1.5 h 1.2: tetrahydrofuran / 16 h / -20 - 20 °C 2.1: 42.86 g / diethyl ether 3.1: H2 / 10 percent Pd/C / ethyl acetate 4.1: TsOH / methanol / 20 °C 5.1: 95 percent / NaOH / methanol / 24 h / Heating View Scheme