174649-09-3

124-63-0

168828-82-8

174649-09-3

To a 1L solution of dichloromethane containing 132.8 g of (R)-3-[3-fluoro-4-(4-morpholinyl)phenyl]-5-hydroxymethyl-2-oxazolidinone and 87.1 g of triethylamine was slowly added 74 g of methanesulfonyl chloride at 0°C under nitrogen protection. The reaction mixture was stirred at 0 °C for 30 min and then gradually warmed up to room temperature. A white solid precipitated during the reaction. Subsequently, a solvent mixture consisting of 1.75 L of water, 6.50 L of dichloromethane and 1 L of ethyl acetate was added to the reaction system and stirring was continued for 30 minutes. Upon completion of the reaction, the white solid product was collected by filtration. A final product of 140 g was obtained with a yield of 105.42% (w/w).