Hydrochloric Acid → HCID 22221159, compound

To a solution of diethyl malonate (3.55 g) in tetrahydrofuran (50 ml) was gradually added sodium hydride (60%, oil, 710 mg) at 0° C. The mixture was stirred for 10 min and a solution of 4-chloromethyl-5-(4,5-dichloro-2-thienyl)isoxazole (2.38 g) in tetrahydrofuran (50 ml) was added dropwise at 0° C. The mixture was stirred at room temperature for 15 hr. The reaction mixture was poured into water, acidified with 2N hydrochloric acid and extracted with ethyl acetate. The ethyl acetate layer was washed with saturated brine, dried (MgSO4) and concentrated. The residue was dissolved in a mixture of 6N hydrochloric acid (60 ml) and acetic acid (90 ml), and the solution was heated under reflux for 8 hr. The reaction mixture was concentrated, and water was added to the residue to give colorless crystals (2.04 g, yield 79%) of 3-[5-(4,5-dichloro-2-thienyl)-4-isoxazolyl]propionic acid. The crystals were recrystallized from ethyl acetate-hexane to give a colorless prism. melting point: 142–143° C.

1. customat 0° C
2. stirringThe mixture was stirred at room temperature for 15 hr
3. extractionextracted with ethyl acetate
4. washThe ethyl acetate layer was washed with saturated brine
5. dry with materialdried (MgSO4)
6. concentrationconcentrated
7. dissolutionThe residue was dissolved in a mixture of 6N hydrochloric acid (60 ml) and acetic acid (90 ml)
8. temperaturethe solution was heated
9. temperatureunder reflux for 8 hr
10. concentrationThe reaction mixture was concentrated
11. additionwater was added to the residue

ORD record

ord-7c7bd169ad4840e29f88eedbbac00ea8

Source dataset

uspto-grants-2006_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07022725B2