1: 74.8 percent / dimethylformamide / 2 h / 100 °C 2: 75 percent / dimethylformamide / 0.5 h / 25 - 30 °C 3: sodium methoxide / dimethylformamide / 0.5 h / 60 - 65 °C 4: 85 percent / aq. 1 N NaOH / various solvent(s) / 3 h / 25 °C 5: 90 percent / triethylamine / xylene / 0.5 h / 115 - 120 °C View Scheme

triethylamine in benzene Reflux;

potassium carbonate in acetonitrile 8 h; Reflux;