1: KOH / ethanol; H2O / 0.67 h / Heating 2: copper bronze, quinoline / 185 °C 3: K2CO3 / acetonitrile / 24 h / Ambient temperature 4: 1.) C-200 (BaCO3*0.8H2O), 2.) H2O / 1.) THF, 2.) THF, reflux, 1 h 5: KOH / ethanol; H2O / 0.67 h / Heating 6: 44 percent / polyphosphoric acid silyl ester (PPSE) / 5 h / 120 °C View Scheme