1: 19.3 percent / HCO2H / CH2Cl2 / 2.5 h / 0 °C / various acid catalysts 2: 46.2 percent / 30percent H2O2 / methanol / 0.17 h / 0 °C 3: 93 percent / CCl4 / 16 h / Heating 4: 88.5 percent / thionyl chloride, pyridine / CH2Cl2 / 0.08 h / 0 °C 5: 90.6 percent / 1N KOH / methanol / 4 h / Ambient temperature 6: 12.1 percent / pyridinium chlorochromate / CH2Cl2 / 2 h / Ambient temperature View Scheme

formic acid in dichloromethane T=0°C; 2.5 h;

1: 19.3 percent / HCO2H / CH2Cl2 / 2.5 h / 0 °C / various acid catalysts 2: 46.2 percent / 30percent H2O2 / methanol / 0.17 h / 0 °C 3: 93 percent / CCl4 / 16 h / Heating 4: 88.5 percent / thionyl chloride, pyridine / CH2Cl2 / 0.08 h / 0 °C 5: 90.6 percent / 1N KOH / methanol / 4 h / Ambient temperature 6: 27.4 percent / chromium trioxide-pyridine complex / 1 h / Ambient temperature 7: 39.1 percent / pyridine / 2.5 h / Heating View Scheme