1: pyridine / 2 h / 20 °C 2: aq. NH4OH / 0.25 h / 20 °C View Scheme

ammonium hydroxide in methanol 0.5 h; Yield given;

1: pyridine / acetonitrile / 1 h / 4 °C 2: 91 g / AcOH / methanol / 48 h / -20 °C View Scheme

2: aq. ammonium hydroxide / methanol 3: 99 percent / pyridine; DMAP 4: 84 percent / H2O / acetonitrile / 9.5 h / 0 - 20 °C 5: 92 percent / tri-n-butyltin hydride; 2,2'-azobisisobutyronitrile / toluene / 0.83 h / 95 °C 6: 100 percent / tetra-n-butylammonium fluoride / tetrahydrofuran / 0 °C 7: 100 percent / aq. ammonia / methanol View Scheme

With  pyridine T=25°C; 2 h;