trifluoroacetic acid T=20°C; 1 h;

1: 81 percent / potassium carbonate / tetrahydrofuran; ethanol / 72 h / 20 °C 2: 88 percent / NaOH / ethanol; H2O / Heating 3: 71 percent / trifluoroacetic acid / 1 h / 20 °C View Scheme

1: 88 percent / NaOH / ethanol; H2O / Heating 2: 71 percent / trifluoroacetic acid / 1 h / 20 °C View Scheme

4 h; Heating;