1: 76 percent / KOH / methanol / 4 h / Heating 2: 53 percent / t-BuONa; 1,1'-bis(diphenylphosphino)ferrocine / Pd2(dba)3 / toluene / 17 h / 100 °C 3: 61 percent / Na2CO3 / Pd(OAc)2 / dimethylformamide / Heating View Scheme

sulfuric acid in water 3 h; Heating;