1: 59 percent / p-TsNHNH2, AcOH / CH2Cl2 / 1.) -20 deg C, 20 h, 2.) room temperature, 4 h 2: 78.7 percent / tetrahydrofuran / 1 h / 0 °C 3: 63.9 percent / LiNH2, NH3 / tetrahydrofuran / 5 h / -33 °C 4: l.) CF3CO2H, (CF3CO)2O, 2.) 10percent KOH / 1.) -18 deg C, 2 h; 2.) EtOH, room temerature, 4 h View Scheme