1: With N,N,N',N',tetramethyl-ethylenediamine; lithium diisopropyl amide in tetrahydrofuran; n-heptane; tert-butyl methyl ether; ethylbenzene T=-50 - -40°C; 74 h; 2: With 1,2,2-trichloro-1,1,2-trichloro-ethane in tetrahydrofuran; n-heptane; tert-butyl methyl ether; ethylbenzene T=-46 - -40°C; 68 h;

1.1: HCOONH4 / Pd/C / octan-1-ol / 6 h / 45 °C 2.1: BuLi; i-Pr2NH / tetrahydrofuran; hexane / 2 h / -75 °C 2.2: 68 percent / 1,1,2-trichloro-1,2,2-trifluoroethane / tetrahydrofuran; hexane / 1 h View Scheme

1.1: 71 percent / KF; tetramethylammonium chloride / dimethylsulfoxide / 6 h / 125 °C 2.1: HCOONH4 / Pd/C / octan-1-ol / 6 h / 45 °C 3.1: BuLi; i-Pr2NH / tetrahydrofuran; hexane / 2 h / -75 °C 3.2: 68 percent / 1,1,2-trichloro-1,2,2-trifluoroethane / tetrahydrofuran; hexane / 1 h View Scheme

1.1: 72 percent / aq. CuSO4 / Heating 2.1: BuLi / tetrahydrofuran; hexane 2.2: 78 percent / 1,1,2-trichloro-1,2,2-trifluoroethane / tetrahydrofuran; hexane 3.1: 71 percent / KF; tetramethylammonium chloride / dimethylsulfoxide / 6 h / 125 °C 4.1: HCOONH4 / Pd/C / octan-1-ol / 6 h / 45 °C 5.1: BuLi; i-Pr2NH / tetrahydrofuran; hexane / 2 h / -75 °C 5.2: 68 percent / 1,1,2-trichloro-1,2,2-trifluoroethane / tetrahydrofuran; hexane / 1 h View Scheme

1.1: 87 percent / hydrazine monohydrate / ethanol / 20 h / Heating 2.1: 72 percent / aq. CuSO4 / Heating 3.1: BuLi / tetrahydrofuran; hexane 3.2: 78 percent / 1,1,2-trichloro-1,2,2-trifluoroethane / tetrahydrofuran; hexane 4.1: 71 percent / KF; tetramethylammonium chloride / dimethylsulfoxide / 6 h / 125 °C 5.1: HCOONH4 / Pd/C / octan-1-ol / 6 h / 45 °C 6.1: BuLi; i-Pr2NH / tetrahydrofuran; hexane / 2 h / -75 °C 6.2: 68 percent / 1,1,2-trichloro-1,2,2-trifluoroethane / tetrahydrofuran; hexane / 1 h View Scheme

1.1: BuLi / tetrahydrofuran; hexane 1.2: 78 percent / 1,1,2-trichloro-1,2,2-trifluoroethane / tetrahydrofuran; hexane 2.1: 71 percent / KF; tetramethylammonium chloride / dimethylsulfoxide / 6 h / 125 °C 3.1: HCOONH4 / Pd/C / octan-1-ol / 6 h / 45 °C 4.1: BuLi; i-Pr2NH / tetrahydrofuran; hexane / 2 h / -75 °C 4.2: 68 percent / 1,1,2-trichloro-1,2,2-trifluoroethane / tetrahydrofuran; hexane / 1 h View Scheme

1.1: BuLi / tetrahydrofuran; hexane / 20 h / -75 °C 1.2: 87 percent / tetrahydrofuran; hexane 2.1: 88 percent / H2; ammonium formate / Pd/C / ethanol / 6 h / 50 °C View Scheme

in tetrahydrofuran; methanol Reflux;

1.1: BuLi; 2,2,6,6-tetramethylpiperidine / tetrahydrofuran; hexane / 0.17 h / -75 °C 1.2: 71 percent / tetrahydrofuran; hexane 2.1: 89 percent / H2; ammonium formate / Pd/C / ethanol / 6 h View Scheme

1: 3-fluoro-4-chloro pyridine With n-butyllithium in tetrahydrofuran; hexane T=-75°C; 20 h; 2: carbon dioxide in tetrahydrofuran; hexane