1: 55 percent / 1.5 M n-butyllithium / tetrahydrofuran; hexane / 1 h / 0 °C 2: 77 percent / NaH / tetrahydrofuran / 3 h / 25 °C 3: 1.) 1 M diisobutylaluminum hydride; 2.) silica / 1.) hexane, -78 deg C, 1 h; 2.) ether, 4 deg C, 15 h View Scheme