1: 76 percent / dimethylformamide / 1 h 2: 73 percent / Bu3SnH, α,α'-azobisisobutyronitrile (AIBN) / toluene; acetonitrile / 1 h / Heating 3: 62 percent / LiN3, CF3CO2H / dimethylformamide / 15 h / 120 °C 4: 86 percent / 0.5 N HNO3, I2 / dioxane; CCl4 / 1 h / Ambient temperature 5: 55 percent / methanolic ammonia / 24 h View Scheme

1: 76 percent / dimethylformamide / 1 h 2: 73 percent / Bu3SnH, α,α'-azobisisobutyronitrile (AIBN) / toluene; acetonitrile / 1 h / Heating 3: 62 percent / LiN3, CF3CO2H / dimethylformamide / 15 h / 120 °C 4: 45 percent / methanolic ammonia / 24 h View Scheme