1: in methanol T=130°C; 0.75 h; 2: With sulfuric acid in methanol T=80 - 85°C; 4 h; 3: With sodium carbonate in methanol; water T=20°C; Cooling with ice;

1.1: phosphorus oxytribromide / 14 h / 140 °C 1.2: 0 °C 1.3: 0 °C 2.1: methanol / 0.75 h / 130 °C 2.2: 4 h / 80 - 85 °C 2.3: 20 °C / Cooling with ice View Scheme