Hydrochloric Acid → HCID 69561163, compound

To a mixture of 3-methyl-5-phenylisoxazole-4-carbaldehyde (4.94 g), ethyl diethylphosphonoacetate (6.53 g) and N,N-dimethylformamide (70 ml) was added sodium hydride (60%, oil, 1.13 g) at 0° C., and the mixture was stirred at room temperature for 3 hr. The reaction mixture was poured into dilute hydrochloric acid, and the mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with saturated brine, dried (MgSO4) and concentrated. The residue was subjected to silica gel column chromatography, and a yellow oil was obtained from a fraction eluted with ethyl acetate-hexane (1:4, volume ratio). A mixture of the obtained yellow oil, 2N hydrochloric acid (50 ml) and acetic acid (50 ml) was refluxed for 3 hr. The reaction mixture was concentrated, and water was added to the residue. The obtained colorless crystals were filtrated to give (E)-3-(3-methyl-5-phenyl-4-isoxazolyl)propenoic acid (4.02 g, yield 93%). The crystals were recrystallized from ethyl acetate-hexane. melting point: 173–174° C.

1. extractionthe mixture was extracted with ethyl acetate
2. washThe ethyl acetate layer was washed with saturated brine
3. dry with materialdried (MgSO4)
4. concentrationconcentrated
5. customa yellow oil was obtained from a fraction
6. washeluted with ethyl acetate-hexane (1:4, volume ratio)
7. additionA mixture of the obtained yellow oil, 2N hydrochloric acid (50 ml) and acetic acid (50 ml)
8. temperaturewas refluxed for 3 hr
9. concentrationThe reaction mixture was concentrated
10. additionwater was added to the residue
11. filtrationThe obtained colorless crystals were filtrated

ORD record

ord-6f0e9402f5224bfcb693f75b1e80c44d

Source dataset

uspto-grants-2006_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07022725B2