1: 76.6 percent / DIEA / CH2Cl2 / 3 h / Ambient temperature 2: 1.) NaH / 1.) DMF, 0 deg C, 1.5 h, 2.) DMF, 40 deg C, 12 h 3: 76.8 percent / H2, HCl / Raney Ni / ethanol / 1.5 h / Ambient temperature 4: 75 percent / DMAP / pyridine / 2 h / 0 °C 5: Tl2CO3, Pd<P(C6H5)3>4 / benzene / 23 h / Ambient temperature 6: nBuNF, HMPA, 4 Angstroem molecular sieves / tetrahydrofuran / 8 h / Ambient temperature 7: MnO2 / CH2Cl2 / 1 h / Heating View Scheme

1: 1.) NaH / 1.) DMF, 0 deg C, 1.5 h, 2.) DMF, 40 deg C, 12 h 2: 76.8 percent / H2, HCl / Raney Ni / ethanol / 1.5 h / Ambient temperature 3: 75 percent / DMAP / pyridine / 2 h / 0 °C 4: Tl2CO3, Pd<P(C6H5)3>4 / benzene / 23 h / Ambient temperature 5: nBuNF, HMPA, 4 Angstroem molecular sieves / tetrahydrofuran / 8 h / Ambient temperature 6: MnO2 / CH2Cl2 / 1 h / Heating View Scheme

1: 76.8 percent / H2, HCl / Raney Ni / ethanol / 1.5 h / Ambient temperature 2: 75 percent / DMAP / pyridine / 2 h / 0 °C 3: Tl2CO3, Pd<P(C6H5)3>4 / benzene / 23 h / Ambient temperature 4: nBuNF, HMPA, 4 Angstroem molecular sieves / tetrahydrofuran / 8 h / Ambient temperature 5: MnO2 / CH2Cl2 / 1 h / Heating View Scheme

manganese(IV) oxide in dichloromethane 1 h; Heating;

1: 75 percent / DMAP / pyridine / 2 h / 0 °C 2: Tl2CO3, Pd<P(C6H5)3>4 / benzene / 23 h / Ambient temperature 3: nBuNF, HMPA, 4 Angstroem molecular sieves / tetrahydrofuran / 8 h / Ambient temperature 4: MnO2 / CH2Cl2 / 1 h / Heating View Scheme

1: Tl2CO3, Pd<P(C6H5)3>4 / benzene / 23 h / Ambient temperature 2: nBuNF, HMPA, 4 Angstroem molecular sieves / tetrahydrofuran / 8 h / Ambient temperature 3: MnO2 / CH2Cl2 / 1 h / Heating View Scheme