1: 51 percent / potassium t-butoxide / 1,2-dimethoxy-ethane; 2-methyl-propan-2-ol 2: 87 percent / n-butyl-lithium, diethylamine / hexane; tetrahydrofuran; hexamethylphosphoric acid triamide / 1.) -78 deg C, 30 min, 2.) room temperature, 1 h 3: 1.) di-isobutylaluminium hydride, 2.) aqueous acetic acid / 1.) toluene 4: 96 percent / toluene-p-sulphonic acid / acetone; H2O / 20 h / 20 °C 5: 87 percent / aqueous potassium hydroxide / methanol 6: 1.) boron trichloride / 1.) dichloromethane, -78 deg C, 1 h, 2.) methanol, - 78 deg C -> room temperature 7: 51 mg / H2 / 5percent Pd-C / ethyl acetate 8: 33 percent / sodium borohydride / methanol / 3 h View Scheme

1: 51 percent / potassium t-butoxide / 1,2-dimethoxy-ethane; 2-methyl-propan-2-ol 2: 87 percent / n-butyl-lithium, diethylamine / hexane; tetrahydrofuran; hexamethylphosphoric acid triamide / 1.) -78 deg C, 30 min, 2.) room temperature, 1 h 3: 1.) di-isobutylaluminium hydride, 2.) aqueous acetic acid / 1.) toluene 4: 96 percent / toluene-p-sulphonic acid / acetone; H2O / 20 h / 20 °C 5: 87 percent / aqueous potassium hydroxide / methanol 6: 1.) boron trichloride / 1.) dichloromethane, -78 deg C, 1 h, 2.) methanol, - 78 deg C -> room temperature 7: 51 mg / H2 / 5percent Pd-C / ethyl acetate View Scheme

1: 51 percent / potassium t-butoxide / 1,2-dimethoxy-ethane; 2-methyl-propan-2-ol 2: 87 percent / n-butyl-lithium, diethylamine / hexane; tetrahydrofuran; hexamethylphosphoric acid triamide / 1.) -78 deg C, 30 min, 2.) room temperature, 1 h 3: 1.) di-isobutylaluminium hydride, 2.) aqueous acetic acid / 1.) toluene 4: 96 percent / toluene-p-sulphonic acid / acetone; H2O / 20 h / 20 °C 5: 87 percent / aqueous potassium hydroxide / methanol 6: 1.) boron trichloride / 1.) dichloromethane, -78 deg C, 1 h, 2.) methanol, - 78 deg C -> room temperature 7: 51 mg / H2 / 5percent Pd-C / ethyl acetate 8: 7 percent / sodium borohydride / methanol / 3 h View Scheme