1: 95.5 percent / K2CO3 / dimethylformamide / 12.5 h / 60 - 70 °C 2: 96.6 percent / POCl3 / CH2Cl2 / 6 h / Ambient temperature 3: 92.7 percent / H2 / 5percent Pd/C / methanol / 760 Torr / Ambient temperature 4: 45.7 percent / AcONa / 120 h / Heating 5: 96.5 percent / H2SO4 / acetic acid / 2.5 h / Heating 6: 96.8 percent / K2CO3 / acetone / 7 h / Heating 7: 57.6 percent / CsF / various solvent(s) / 3 h / 190 - 195 °C / Heating 8: 1.) (CF3CO)2O, 30percent aq. H2O2, 2.) NaIO4, 3.) 1percent aq NaHCO3 View Scheme