Ethyl pyruvate → Ethyl 2-hydroxyiminopropionate

A mixture of ethyl pyruvate (9.50 g), hydroxylamine hydrochloride (6.82 g), sodium acetate (10.1 g) and ethanol (150 ml) was heated under reflux for 17 hours. The reaction mixture was concentrated, and the residue was diluted with water and extracted with ethyl acetate. The ethyl acetate layer was washed with water, dried (MgSO4), and then concentrated. The residual crystals were recrystallized from ethyl acetate-hexane to obtain ethyl E-2-hydroxyiminopropionate (6.33 g, yield 59%) as colorless crystals. m.p. 98-99° C.

1. temperaturewas heated
2. temperatureunder reflux for 17 hours
3. concentrationThe reaction mixture was concentrated
4. additionthe residue was diluted with water
5. extractionextracted with ethyl acetate
6. washThe ethyl acetate layer was washed with water
7. dry with materialdried (MgSO4)
8. concentrationconcentrated
9. customThe residual crystals were recrystallized from ethyl acetate-hexane

ORD record

ord-d0676063145d4f109d3710453fd474dc

Source dataset

uspto-grants-2002_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06495581B1