hydrogen; triethylamine; palladium on activated charcoal in N,N-dimethyl-formamide; acetonitrile 3 h; Ambient temperature;

1: 79 percent / tetrahydrofuran / 8 h / Heating 2: 100 percent / H2 / 10 percent Pd/C / tetrahydrofuran / 3 h / Ambient temperature 3: 84 percent / Et3N / CH2Cl2 / 1 h / 0 °C 4: 48 percent / Cs2CO3 / dimethylformamide / 16 h / 760 Torr / Ambient temperature 5: 90 percent / H2, Et3N / 10 percent Pd/C / acetonitrile; dimethylformamide / 3 h / Ambient temperature View Scheme

1: 84 percent / Et3N / CH2Cl2 / 1 h / 0 °C 2: 48 percent / Cs2CO3 / dimethylformamide / 16 h / 760 Torr / Ambient temperature 3: 90 percent / H2, Et3N / 10 percent Pd/C / acetonitrile; dimethylformamide / 3 h / Ambient temperature View Scheme