hydrogenchloride in tetrahydrofuran Ambient temperature;

1: 90 percent / n-BuLi / tetrahydrofuran; hexane / 1.) -25 deg C, 2.5 h, 2.) -40 deg C to r.t., overnight 2: 96 percent / n-BuLi / 1.) THF, hexane, -25 deg C, 2.5 h, 2.) HMPA, -78 deg C, 2 h; -78 deg C to r.t., overnight 3: 85 percent / 3 N aq. HCl / tetrahydrofuran / Ambient temperature View Scheme