Reaktion #2178275

Reaktionsgleichung

sodium hydroxide

tetrahydrofuran

methyl 4-{[2-ethyl-1-(5-fluoro-3-methyl-1-benzofuran-2-yl)butyl]amino}benzoate

sodium hydroxide

sodium hydroxide

→

title compound

Ausbeute 61.0%

4-{[2-ethyl-1-(5-fluoro-3-methyl-1-benzofuran-2-yl)butyl]amino}benzoic acid

Ausbeute 61.0%

Lösungsmittel

ethanol

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe mixture was heated
2. 2
   Temperaturunder reflux for 14 hr
3. 3
   Temperaturwith heating
4. 4
   Temperaturunder reflux for 2 hr
5. 5
   workup.STIRRINGthe mixture was further stirred
6. 6
   Temperaturwith heating
7. 7
   Temperaturunder reflux for 1 hr
8. 8
   EinengenThe reaction mixture was concentrated under reduced pressure, 8N aqueous sodium hydroxide solution (4.0 mL), ethanol (4 mL) and tetrahydrofuran (4 mL)
9. 9
   workup.ADDITIONwere added
10. 10
    workup.STIRRINGthe mixture was further stirred
11. 11
    Temperaturwith heating
12. 12
    Temperaturunder reflux for 1 hr
13. 13
    workup.ADDITION1N hydrochloric acid was added
14. 14
    Extraktionthe mixture was extracted with ethyl acetate
15. 15
    WaschenThe extract was washed with saturated brine
16. 16
    Trocknendried over magnesium sulfate
17. 17
    Einengenconcentrated under reduced pressure
18. 18
    SonstigeThe residue was purified by silica gel column chromatography (hexane-ethyl acetate 100:0-70:30, v/v)

Vorschrift

To a mixture of methyl 4-{[2-ethyl-1-(5-fluoro-3-methyl-1-benzofuran-2-yl)butyl]amino}benzoate (709 mg) synthesized above, tetrahydrofuran (6 mL) and ethanol (6 mL) was added 1N aqueous sodium hydroxide solution (3.7 mL), and the mixture was heated under reflux for 14 hr. 1N Aqueous sodium hydroxide solution (4.0 mL) was added, and the mixture was further stirred with heating under reflux for 2 hr. 8N Aqueous sodium hydroxide solution (2.0 mL) and ethanol (2 mL) were added to the mixture, and the mixture was further stirred with heating under reflux for 1 hr. The reaction mixture was concentrated under reduced pressure, 8N aqueous sodium hydroxide solution (4.0 mL), ethanol (4 mL) and tetrahydrofuran (4 mL) were added, and the mixture was further stirred with heating under reflux for 1 hr. The reaction mixture was allowed to cool to room temperature, 1N hydrochloric acid was added, and the mixture was extracted with ethyl acetate. The extract was washed with saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane-ethyl acetate 100:0-70:30, v/v) to give the title compound (412 mg, 61%) as a colorless amorphous form.

Quelle