(R)-(+)-4-HYDROXY-2-PYRROLIDINONE

In a 250mL four-necked flask, add 70mL of water and 2.5mL of triethylamine, stir well, and reduce the temperature to 5~10C. Add 5g of 2,4-dioxopyrrolidine hydrochloride under stirring, and add 2.77g of potassium borohydride. Add 5g of 2,4-dioxopyrrolidine hydrochloride under stirring, add potassium borohydride 2.77g. Hold at 5 for 0.5h, warm up to 25 and hold for 1h, concentrate under reduced pressure with a water bath temperature of 80, and concentrate to dryness. Add 5mL of methanol fusion crystallization at 20-25 overnight, filtration, washed with 10mL of methanol, dried in a vacuum at 50 dry 0.5h, the crude 3.42g, the content of 83.91% (mass fraction), folding purity yield of 69.23%. Chiral split preparation (R)-4-hydroxy-2-pyrrolidone.