1: 1.) n-butyllithium / 1.) tetrahydrofuran, hexane, 2 h, room temperature, 2.) reflux, 18 h, THF 2: 100 percent / PPTS / ethanol / 6 h / Heating 3: 96 percent / dimethylsulfoxide, triethylamine / diethyl ether / 4.5 h / Ambient temperature 4: 100 percent / 0.17 h / 600 °C 5: 92 percent / palladium acetate, p-benzoquinone / acetonitrile / 6 h / Ambient temperature View Scheme