1: With n-butyllithium in tetrahydrofuran; hexane T=0°C; 2 h; 2: With boric acid trimethyl ester in tetrahydrofuran; hexane T=0 - 20°C; 3: With ammonium chloride in tetrahydrofuran; hexane; water T=20°C; 1 h;

1.1: 80 percent / NaH / 5 h / 0 °C 2.1: n-butyllithium / tetrahydrofuran; hexane / 2 h / 0 °C 2.2: B(OCH3)3 / tetrahydrofuran; hexane / 0 - 20 °C 2.3: 44 percent / NH4Cl / tetrahydrofuran; hexane; H2O / 1 h / 20 °C View Scheme