1: 53 percent / n-BuLi / tetrahydrofuran; hexamethylphosphoric acid triamide / 1.) 0 deg C, 4 h; 2.) 27 deg C, 40 h 2: 83 percent / hydrogen / Pd/BaSO4 / methanol / 30 h 3: 93 percent / oxalic acid / acetone; H2O / 1 h / 60 °C 4: 62 percent / n-BuLi / tetrahydrofuran / 1 h / -78 °C 5: 69 percent / 7 h / Heating 6: 47 percent Chromat. / Al2O3 / benzene / 1 h / Heating View Scheme

1: 83 percent / hydrogen / Pd/BaSO4 / methanol / 30 h 2: 93 percent / oxalic acid / acetone; H2O / 1 h / 60 °C 3: 62 percent / n-BuLi / tetrahydrofuran / 1 h / -78 °C 4: 69 percent / 7 h / Heating 5: 47 percent Chromat. / Al2O3 / benzene / 1 h / Heating View Scheme

1: 62 percent / n-BuLi / tetrahydrofuran / 1 h / -78 °C 2: 69 percent / 7 h / Heating 3: 47 percent Chromat. / Al2O3 / benzene / 1 h / Heating View Scheme

1: 93 percent / oxalic acid / acetone; H2O / 1 h / 60 °C 2: 62 percent / n-BuLi / tetrahydrofuran / 1 h / -78 °C 3: 69 percent / 7 h / Heating 4: 47 percent Chromat. / Al2O3 / benzene / 1 h / Heating View Scheme

1: 69 percent / 7 h / Heating 2: 47 percent Chromat. / Al2O3 / benzene / 1 h / Heating View Scheme

aluminum oxide in benzene 1 h; Heating;

lithium aluminium tetrahydride in diethyl ether T=-40°C; 1.5 h;