n-butyllithium in tetrahydrofuran; N,N,N',N',N'',N''-hexamethylphosphoric triamide; hexane 1.) -40 deg C; 2.) reflux, 30 h;

1: 80 percent / Amberlyst A15 / CH2Cl2 / 2 h / Ambient temperature 2: 82 percent / BuLi, NaI / tetrahydrofuran / 1.) -80 deg C to room temperature, 2.) room temperature, 3 d View Scheme