zinc(II) chloride; lithium diisopropyl amide in tetrahydrofuran; diethyl ether T=-10°C;

1: 93 percent / potassium carbonate / methanol; H2O / 3 h 2: 90 percent / lithium diisopropylamide, HMPA / tetrahydrofuran / -78 deg C -> room temperature, overnight 3: 1.) DIBAL-H, 2.) 6percent aq. sulfuric acid / 1.) toluene, hexane, 0 deg C, 3 h, 2.) room temperature, 1 h 4: lithium diisopropylamide, anhydrous zinc chloride / tetrahydrofuran; diethyl ether / -10 °C View Scheme

1: 90 percent / lithium diisopropylamide, HMPA / tetrahydrofuran / -78 deg C -> room temperature, overnight 2: 1.) DIBAL-H, 2.) 6percent aq. sulfuric acid / 1.) toluene, hexane, 0 deg C, 3 h, 2.) room temperature, 1 h 3: lithium diisopropylamide, anhydrous zinc chloride / tetrahydrofuran; diethyl ether / -10 °C View Scheme

1: 68 percent / lithium aluminium hydride / diethyl ether / 20 h / Heating 2: 93 percent / potassium carbonate / methanol; H2O / 3 h 3: 90 percent / lithium diisopropylamide, HMPA / tetrahydrofuran / -78 deg C -> room temperature, overnight 4: 1.) DIBAL-H, 2.) 6percent aq. sulfuric acid / 1.) toluene, hexane, 0 deg C, 3 h, 2.) room temperature, 1 h 5: lithium diisopropylamide, anhydrous zinc chloride / tetrahydrofuran; diethyl ether / -10 °C View Scheme

1: 1.) DIBAL-H, 2.) 6percent aq. sulfuric acid / 1.) toluene, hexane, 0 deg C, 3 h, 2.) room temperature, 1 h 2: lithium diisopropylamide, anhydrous zinc chloride / tetrahydrofuran; diethyl ether / -10 °C View Scheme

1: 249 g / n-butyllithium / hexane; tetrahydrofuran / 2 h 2: 68 percent / lithium aluminium hydride / diethyl ether / 20 h / Heating 3: 93 percent / potassium carbonate / methanol; H2O / 3 h 4: 90 percent / lithium diisopropylamide, HMPA / tetrahydrofuran / -78 deg C -> room temperature, overnight 5: 1.) DIBAL-H, 2.) 6percent aq. sulfuric acid / 1.) toluene, hexane, 0 deg C, 3 h, 2.) room temperature, 1 h 6: lithium diisopropylamide, anhydrous zinc chloride / tetrahydrofuran; diethyl ether / -10 °C View Scheme