1.1: n-butyllithium / tetrahydrofuran / 1 h / -20 °C 1.2: 2.5 h / 23 °C 2.1: dysprosium(III) trifluoromethanesulfonate / toluene / 1 h / 23 - 80 °C View Scheme

1.1: n-butyllithium / tetrahydrofuran / 1 h / -20 °C 1.2: 2.5 h / 23 °C 2.1: dysprosium(III) trifluoromethanesulfonate / toluene / 1 h / 23 - 80 °C View Scheme

1: 1.) n-BuLi, TMEDA / 1.) THF, 0 deg C to rt, 2 h, 2.) THF, -78 deg C, 4 h, rt, overnight 2: 75 percent / HCl / CHCl3 / Ambient temperature; other reagent, solvent, temperature View Scheme

1: 1.) n-BuLi, TMEDA / 1.) THF, 0 deg C to rt, 2 h, 2.) THF, -78 deg C, 4 h, rt, overnight 2: 75 percent / HCl / CHCl3 / Ambient temperature; other reagent, solvent, temperature View Scheme