General procedure for the synthesis of 2,3-dichloroanisole from 2,3-dichlorophenol and dimethyl sulfate: 2,3-dichlorophenol (20.0 g, 122.7 mmol) was placed in a reaction flask, 120 mL of acetone was added to dissolve it, followed by the addition of potassium carbonate (18.7 g, 135.0 mmol), and magnetically stirred for 0.5 hours. Then dimethyl sulfate (17.0 g, 135.0 mmol) was slowly added dropwise through a dropping funnel and heated to 60°C and refluxed for 3 hours. The progress of the reaction was monitored by thin layer chromatography (TLC) (unfolding agent: petroleum ether/ethyl acetate=5:1, Rf=0.8). After completion of the reaction, it was cooled to room temperature, potassium carbonate was removed by filtration with a pump and the filter cake was washed with acetone. After evaporation to remove acetone, ethyl acetate and saturated sodium bicarbonate solution were added sequentially, and the organic phase was washed twice each time with saturated aqueous sodium chloride solution, and then the organic phase was dried with anhydrous sodium sulfate. After filtration, the solvent was evaporated under reduced pressure to give 2,3-dichloroanisole. The product was a colorless oil with a yield of 21.5 g and 99.1%.
