Synthesis
In a reaction tube, 262 mg of ethyl p-iodobenzoate (MW = 262.04, 1.0 mmol) was added, followed by 153 mg of sodium salt of methyl ketene sulfonate (MW = 102.09, 1.2 mmol, 80%), 28 mg of sodium salt of L-proline (MW = 137.05, 0.2 mmol), 19 mg of CuI (MW = 190.45, 0.1 mmol), 2 ml of DMSO as a solvent, under the protection of nitrogen, the reaction was carried out in an oil bath at 80 for 36 h. Cooling, 4 ml of water was added, and each time it was extracted with 10 ml of ethyl acetate, and repeated three times, and the extract was washed with saturated saline water, dried with anhydrous sodium sulfate, and then filtered, and the filtrate was distilled under reduced pressure, and separated over silica gel columns (the eluent petroleum ether: ethyl acetate = 3: 1 ), obtained 158 mg product 4-methylsulfonylbenzoic acid methyl ester, yield 77%.
