1: pyridine / 1.) 1 h; 2.) -10 deg C, 2 d 2: 77 percent / sodium azide / dimethylformamide / 3 h / 90 - 95 °C 3: 89 percent / pyridine, 29percent aq. NH4OH / 3 h / 55 °C View Scheme

1: pyridine / 1.) 1 h; 2.) -10 deg C, 2 d 2: 77 percent / sodium azide / dimethylformamide / 3 h / 90 - 95 °C 3: 89 percent / pyridine, 29percent aq. NH4OH / 3 h / 55 °C 4: 90 percent / 5percent Pd/C, H2 / ethanol / 18 h / Ambient temperature View Scheme