1: 92 percent / methanolic NH3 / 16 h / Ambient temperature 2: 82 percent / AgNO3, pyridine / tetrahydrofuran / 3.5 h / Ambient temperature 3: 85 percent / DMAP / acetonitrile / 28 h / Ambient temperature 4: 90 percent / Bu3SnH, 2,2'-azobis(2-methylpropionitrile) / benzene / 0.33 h / Heating 5: 83 percent / aq. AcOH / 1 h / Ambient temperature 6: 1) hydrazine, 2) Raney Ni / 1) 90 min, reflux, 2) aq. EtOH, reflux, 2 h View Scheme

ammonia 16 h; Ambient temperature;

1: 86 percent / NH3/MeOH / 48 h / Ambient temperature 2: 1.) hydrazine, 2.) Raney-Ni / 1.) 90 deg C, 1 h, 2.) EtOH, reflux, 1 h View Scheme