Hydrochloric Acid → (4s,5s)-4-Benzyl-5-methyl-2-oxazolidinone

Temperature

0 °C

5.5 ml of water was added to 0.50 g (2.40 mmol) of (2S,3S)-2-benzyl-3-hydroxybutanohydrazide (optical purity: >99.9%e.e.; anti/syn>99/1), and the mixture was cooled to 0° C. A 0.30 g (2.88 mmol) of 35% HCl was added thereto dropwise. After the addition, then an aqueous solution of 0.20 g (2.88 mmol) of sodium nitrite dissolved in 1.0 ml of water was further added thereto dropwise slowly. After the reaction mixture was stirred for 1 hour at that temperature, the thus prepared reaction mixture was added to 10 ml of warm water (50° C.) dropwise over 0.5 hour. After the addition, the mixture was further stirred for 1 hour, cooled to room temperature, and then extracted thrice with a 10 ml portion of toluene. The extracted toluene was then concentrated to give 0.33 g of a crude product. The crude product was subjected to column chromatography (hexane/ethyl acetate=1/1 by volume) to obtain 0.25 g (52%) of the title compound. Melting point: 115.5° C. Optical purity: >99.9%e.e. anti/syn>99/1

1. additionAfter the addition
2. additionwas further added
3. customthe thus prepared reaction mixture
4. additionAfter the addition
5. stirringthe mixture was further stirred for 1 hour
6. temperaturecooled to room temperature
7. extractionextracted thrice with a 10 ml portion of toluene
8. concentrationThe extracted toluene was then concentrated
9. customto give 0.33 g of a crude product

ORD record

ord-e8e9e72dc3db451e9d5ffd9cb5d664ce

Source dataset

uspto-grants-2002_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06403804B1