1: 74 percent / tetrahydrofuran / 0.25 h / -10 °C 2: 83 percent / aq. trifluoroacetic acid / CH2Cl2 / 0.08 h / 20 °C 3: 95 percent / pyridine / 2 h 4: 94 percent / triethylamine / CH2Cl2 / 0.08 h / 20 °C 5: 61 percent / tetrakis(triphenylphosphane)palladium(0) / tetrahydrofuran / 48 h / Heating 6: 92 percent / phosphoryl chloride / 0.25 h / 50 °C 7: 83 percent / aluminum(III) chloride; tBuNH2-BH3 / CH2Cl2 / 0.5 h / Heating View Scheme

1: 74 percent / tetrahydrofuran / 0.25 h / -10 °C 2: 83 percent / aq. trifluoroacetic acid / CH2Cl2 / 0.08 h / 20 °C 3: 95 percent / pyridine / 2 h 4: 94 percent / triethylamine / CH2Cl2 / 0.08 h / 20 °C 5: 61 percent / tetrakis(triphenylphosphane)palladium(0) / tetrahydrofuran / 48 h / Heating View Scheme