1: 70 percent / pyridine / 20 h / Ambient temperature 2: 62 percent / dry H2S / pyridine / 15 h / 12 °C / sealed tube 3: 75 percent / Raney Ni / ethanol; H2O / 0.5 h / Heating 4: 67 percent / NH3 (g) / methanol / 10 h / 100 °C / sealed tube View Scheme

With  methylamine T=0 - 5°C; 2 h;  Yield given;   

Multi-step reaction with 3 steps 1: 70 percent / pyridine / 20 h / Ambient temperature2: 62 percent / dry H2S / pyridine / 15 h / 12 °C / sealed tube3: 75 percent / Raney Ni / ethanol; H2O / 0.5 h / Heating  

Multi-step reaction with 2 steps 1: 70 percent / pyridine / 20 h / Ambient temperature2: 62 percent / dry H2S / pyridine / 15 h / 12 °C / sealed tube