1: 78 percent / dimethylformamide / 4 h / 80 °C 2: 1.) NaH, 2.) BuLi, 3.) Bf3*OEt2, 4.) KF 3: 90 percent / 10percent KOH / ethanol / 3 h / Heating 4: 81 percent / conc. HCl / methanol / 4 h / Heating View Scheme