1: With n-butyllithium in tetrahydrofuran; hexane T=-78°C; 2.5 h; 2: With boric acid trimethyl ester in tetrahydrofuran; hexane T=20°C; 8 h; 3: With hydrogenchloride; water in tetrahydrofuran; hexane 1 h;

1: With n-butyllithium in tetrahydrofuran T=-78°C; 0.75 h; 2: With boric acid trimethyl ester in tetrahydrofuran T=-78°C; 1 h; 3: With hydrogenchloride T=20°C; 1 h;

1.1: 77 percent / K2CO3 / acetonitrile / Heating 2.1: BuLi / tetrahydrofuran; hexane / -78 °C 2.2: B(OMe)3 / tetrahydrofuran; hexane / -78 - 20 °C View Scheme