1: 95 percent / ethanol / 1 h / Ambient temperature 2: 78 percent / potassium carbonate / dimethylformamide / 2 h / 140 - 150 °C 3: 86 percent / conc. H2SO4 / H2O; acetic acid / 1.5 h / Heating View Scheme

1: toluene / 2 h / 0 - 20 °C 2: sodium hydride / N,N-dimethyl-formamide / 90 °C View Scheme

1: aq. ethanol / 2 h / 0 °C 2: 95 percent / NaH / 1,2-dimethoxy-ethane / 1 h / 0 °C 3: 1.) O3 2.) Me2S / 1.) MeOH, CH2Cl2, -78 deg C, 1h 2.) -78 deg C --> RT 4: NaH / dimethylformamide / 30 °C 5: 80 percent / 2N aq. HCl / tetrahydrofuran / 5 h / Heating 6: 79 percent / dimethylsulfoxide / 16 h / 70 °C View Scheme

1: 77 percent / triethylamine / CH2Cl2 / 1 h / Ambient temperature 2: 66 percent / anhydrous potassium carbonate / dimethylformamide / 4 h / 130 °C 3: 100 percent / K2CO3 / ethanol; H2O / 2 h / Heating 4: 2.) 1 N aq. HCl / 1.) pyridine, reflux, 5.5 h View Scheme

1: 95 percent / ethanol / 1 h / Ambient temperature 2: 78 percent / potassium carbonate / dimethylformamide / 2 h / 140 - 150 °C View Scheme