1: 91 percent / n-butyllithium / hexane; tetrahydrofuran / -78 to 20 deg C 2: 91 percent / Et3N / bis-triphenylphosphine palladium dichloride / dimethylformamide / 1.5 h / 75 °C 3: 95 percent / H2 / Lindlar's catalyst, quinoline / hexane / 0.75 h 4: 2.) AG 50W-X4 resin / 1.) iso-octane, 4 h, reflux 2.) methanol, CH2Cl2, 24 h, r.t. 5: 80 percent / diethyl ether / 0.33 h / -78 °C View Scheme