tetrabutyl ammonium fluoride in tetrahydrofuran T=55°C; 12 h;

ethylenediamine in methanol 0.0666667 h; Microwave irradiation;

tri-n-butyl-tin hydride in xylene T=130°C; 10 h;

1: With hydrazine hydrate in ethanol; diethylene glycol 1 h; HeatingHuang-Minlon reduction; 2: With potassium hydroxide 2 h; Heating;

1: 56 percent / Et2Zn / toluene / 8 h / Ambient temperature 2: DIBAL / CH2Cl2 3: imidazole / dimethylformamide / 10 h / 55 °C 4: 61 percent / CuBr / chlorobenzene / 4 h / 115 °C 5: 96 percent / aq. NaOH / methanol; tetrahydrofuran 6: 93 percent / Li, NH3 / tetrahydrofuran / 2 h / -78 °C 7: 1.) n-BuLi, ClPO(NMe2)2, 2.) Li, EtNH2 / 1.) THF, HMPA, 2.) THF, t-BuOH, 0 deg C, 3 h 8: 95 percent / (n-Bu)4NF / tetrahydrofuran / 12 h / 55 °C View Scheme

1: imidazole / dimethylformamide / 10 h / 55 °C 2: 61 percent / CuBr / chlorobenzene / 4 h / 115 °C 3: 96 percent / aq. NaOH / methanol; tetrahydrofuran 4: 93 percent / Li, NH3 / tetrahydrofuran / 2 h / -78 °C 5: 1.) n-BuLi, ClPO(NMe2)2, 2.) Li, EtNH2 / 1.) THF, HMPA, 2.) THF, t-BuOH, 0 deg C, 3 h 6: 95 percent / (n-Bu)4NF / tetrahydrofuran / 12 h / 55 °C View Scheme

1: 72 percent / Pb(OAc)4, Cu(OAc)2, pyridine / acetonitrile / 80 °C 2: 56 percent / Et2Zn / toluene / 8 h / Ambient temperature 3: DIBAL / CH2Cl2 4: imidazole / dimethylformamide / 10 h / 55 °C 5: 61 percent / CuBr / chlorobenzene / 4 h / 115 °C 6: 96 percent / aq. NaOH / methanol; tetrahydrofuran 7: 93 percent / Li, NH3 / tetrahydrofuran / 2 h / -78 °C 8: 1.) n-BuLi, ClPO(NMe2)2, 2.) Li, EtNH2 / 1.) THF, HMPA, 2.) THF, t-BuOH, 0 deg C, 3 h 9: 95 percent / (n-Bu)4NF / tetrahydrofuran / 12 h / 55 °C View Scheme

1: 61 percent / CuBr / chlorobenzene / 4 h / 115 °C 2: 96 percent / aq. NaOH / methanol; tetrahydrofuran 3: 93 percent / Li, NH3 / tetrahydrofuran / 2 h / -78 °C 4: 1.) n-BuLi, ClPO(NMe2)2, 2.) Li, EtNH2 / 1.) THF, HMPA, 2.) THF, t-BuOH, 0 deg C, 3 h 5: 95 percent / (n-Bu)4NF / tetrahydrofuran / 12 h / 55 °C View Scheme

1: 1.) n-BuLi, ClPO(NMe2)2, 2.) Li, EtNH2 / 1.) THF, HMPA, 2.) THF, t-BuOH, 0 deg C, 3 h 2: 95 percent / (n-Bu)4NF / tetrahydrofuran / 12 h / 55 °C View Scheme

1: 93 percent / Li, NH3 / tetrahydrofuran / 2 h / -78 °C 2: 1.) n-BuLi, ClPO(NMe2)2, 2.) Li, EtNH2 / 1.) THF, HMPA, 2.) THF, t-BuOH, 0 deg C, 3 h 3: 95 percent / (n-Bu)4NF / tetrahydrofuran / 12 h / 55 °C View Scheme