1: 100 percent / MeONa / methanol / 0.5 h 2: 1.) NaH / 1.) THF, RT, 30 min, 2.) THF, RT, 3 h 3: NaN3 / dimethylformamide / 3 h / 60 °C 4: H2 / 10percent Pd/C / ethanol / 12 h / Ambient temperature View Scheme

1: 97.2 percent / K2CO3 / methanol / 2.5 h / Ambient temperature 2: 80.8 percent / Ph3P, diethyl azidocarboxylate / tetrahydrofuran / 2.5 h / Ambient temperature 3: 96.7 percent / NaOMe / methanol / 1 h / Ambient temperature View Scheme