GENERAL PROCEDURE: L-aminopropanol (78 μL, 1 mmol) was added to a solution of cesium carbonate (33 mg, 0.1 mmol) in dimethylsulfoxide-d6 (1 mL) in a polytetrafluoroethylene tube. The PTFE tubing containing the reaction mixture was loaded into a 30 mL high-pressure reactor. The autoclave was frozen with liquid nitrogen (-196 °C) before connecting to a vacuum line to remove air. After the mixture was vacuum evaporated at -196°C and warmed to room temperature, the autoclave was charged with carbon dioxide (3 atm). The autoclave was stirred at 150 °C for 24 hours. Upon completion of the reaction, the reaction mixture was analyzed by 1H NMR to determine the crude product yield, which was calculated based on the ratio between the product and the internal standard (N,N-dimethylformamide). Subsequently, dimethyl sulfoxide-d6 was removed by distillation under vacuum; then, the slurry product was purified by silica gel column chromatography (eluent: hexane/ethyl acetate, 3:1) to afford the target product, (S)-4-methyloxazolidin-2-one, as a colorless oil with an isolated yield of 36% (36.4 mg, 0.36 mmol).
