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

<b>Multi-step reaction with 2 steps<br /> </b>1: 95.5 percent / K₂CO₃ / dimethylformamide / 12.5 h / 60 - 70 &deg;C<br />2: 96.6 percent / POCl₃ / CH₂Cl₂ / 6 h / Ambient temperature<br /> <br /> &nbsp;

<b>Multi-step reaction with 4 steps<br /> </b>1: 94.6 percent / K₂CO₃ / dimethylformamide / 6 h / 60 - 65 &deg;C<br />2: 73.6 percent / HCOOH, 30percent aq. H₂O₂ / 3.5 h / 0 - 5 &deg;C<br />3: 95.5 percent / K₂CO₃ / dimethylformamide / 12.5 h / 60 - 70 &deg;C<br />4: 96.6 percent / POCl₃ / CH₂Cl₂ / 6 h / Ambient temperature<br /> <br /> &nbsp;