1: 96 percent / pyridine / 26 h / 25 °C 2: 27 percent / imidazole / dimethylformamide / 27 h / 25 °C 3: dimethylformamide 4: n-Bu3SnH, AIBN / toluene / Heating 5: TBAF / tetrahydrofuran 6: aq. CH3COOH / Ambient temperature 7: conc. aq. NH3 View Scheme

1: 96 percent / pyridine / 26 h / 25 °C 2: 50 percent / imidazole / dimethylformamide / 27 h / 25 °C 3: dimethylformamide / 100 h / 24 °C 4: n-Bu3SnH, AIBN / toluene / 6 h / Heating 5: TBAF / tetrahydrofuran / 5 h / 22 °C 6: 80percent aq. CH3COOH / 0.5 h / Ambient temperature 7: conc. aq. NH3 / 2 h / 55 °C View Scheme

Multi-step reaction with 3 steps 1: 96 percent / pyridine / 26 h / 25 °C2: 50 percent / imidazole / dimethylformamide / 27 h / 25 °C3: dimethylformamide / 100 h / 24 °C