selenium(IV) oxide in acetic acid 48 h; Heating;

1: potassium tert-butoxide / tetrahydrofuran / 14 h / Ambient temperature 2: 70 percent / ammonium acetate / acetic acid; tetrahydrofuran / 4 h / Heating 3: 85 percent / 1.) nickel(II) dichloride hexahydrate 2.)sodium borohydride / ethanol / 1.) 10 min, rt 2.) reflux, 12 h 4: 13 percent / selenium dioxide / acetic acid / 48 h / Heating View Scheme

1: potassium tert-butoxide / tetrahydrofuran / 14 h / Ambient temperature 2: 70 percent / ammonium acetate / acetic acid; tetrahydrofuran / 4 h / Heating 3: 85 percent / 1.) nickel(II) dichloride hexahydrate 2.)sodium borohydride / ethanol / 1.) 10 min, rt 2.) reflux, 12 h 4: 13 percent / selenium dioxide / acetic acid / 48 h / Heating View Scheme

1: tetrakis(triphenylphosphine)palladium(0) / toluene / 72 h / 90 °C 2: HCl / 60 °C View Scheme

1: 1) n-BuLi / 1) Et2O, hexane, THF, -78 deg C, 2) THF, -78 deg C, 5 min 2: 1) NaH / 2) HMPA, r.t., 20 min 3: Mg-monoperoxyphthalate / methanol / 1 h / Ambient temperature 4: 1) n-BuLi / 1) Et2O, hexane, THF, -78 deg C, 2) THF, -78 deg C, 5 min 5: 1) n-BuLi / 1) Et2O-hexane-THF, -78 deg C, 5-10 min, 2) -78 deg C View Scheme

1: 1) n-BuLi / 1) Et2O, hexane, THF, -78 deg C, 2) THF, -78 deg C, 5 min 2: 1) NaH / 2) HMPA, r.t., 20 min 3: Mg-monoperoxyphthalate / methanol / 1 h / Ambient temperature 4: 1) n-BuLi / 1) Et2O, hexane, THF, -78 deg C, 2) THF, -78 deg C, 5 min 5: 1) n-BuLi / 1) Et2O-hexane-THF, -78 deg C, 5-10 min, 2) -78 deg C View Scheme

1: Mg-monoperoxyphthalate / methanol / 1 h / Ambient temperature 2: 1) n-BuLi / 1) Et2O, hexane, THF, -78 deg C, 2) THF, -78 deg C, 5 min 3: 1) n-BuLi / 1) Et2O-hexane-THF, -78 deg C, 5-10 min, 2) -78 deg C View Scheme

1: 1) n-BuLi / 1) Et2O, hexane, THF, -78 deg C, 2) THF, -78 deg C, 5 min 2: 1) n-BuLi / 1) Et2O-hexane-THF, -78 deg C, 5-10 min, 2) -78 deg C View Scheme

n-butyllithium 1) Et2O-hexane-THF, -78 deg C, 5-10 min, 2) -78 deg C; Multistep reaction;