234082-35-0

67-56-1

65055-17-6

234082-35-0

Example 1 Preparation of methyl 3-chloro-4-fluorobenzoate In a 250 mL four-necked round-bottomed flask assembled with a mechanical stirrer, condenser tube and thermometer, 86.5 g of 3-chloro-4-fluorobenzoyl chloride was added. 28.1 g of anhydrous methanol was added slowly through a constant pressure dropping funnel. The reaction was exothermic and the temperature was raised to 60 °C spontaneously. The titration rate of methanol was controlled to maintain the reaction temperature at about 60 °C. The reaction mixture was stirred for 1 hour and the excess methanol was removed by distillation. A final 80 g of yellow oily material was obtained as methyl 3-chloro-4-fluorobenzoate in 97.29% yield.