Hydrochloric Acid → 2-Benzofurancarboxaldehyde, 3-methyl-

To a solution (40 mL) of ethyl 3-methyl-1-benzofuran-2-carboxylate (2.00 g) in tetrahydrofuran was added dropwise 1.5M diisobutylaluminum hydride toluene solution (19.6 mL) at 0° C., and the mixture was stirred for 2 hr. 1N Hydrochloric acid was added to quench the reaction, and the mixture was extracted with ethyl acetate. The extract was washed with saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure to give a white solid. To a solution (40 mL) of the obtained solid in dichloromethane was added Dess-Martin periodinane (4.96 g) at 0° C., and the mixture was stirred at room temperature overnight. Saturated sodium sulfite aqueous solution was added to quench the reaction, and the mixture was extracted with ethyl acetate. The extract was washed with saturated aqueous sodium hydrogen carbonate solution and saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate:hexane=1:9, volume ratio) to give the title object compound (753 mg, 48%) as a white solid.

1. customto quench
2. customthe reaction
3. extractionthe mixture was extracted with ethyl acetate
4. washThe extract was washed with saturated brine
5. dry with materialdried over magnesium sulfate
6. concentrationconcentrated under reduced pressure
7. customto give a white solid
8. stirringthe mixture was stirred at room temperature overnight
9. customto quench
10. customthe reaction
11. extractionthe mixture was extracted with ethyl acetate
12. washThe extract was washed with saturated aqueous sodium hydrogen carbonate solution and saturated brine
13. dry with materialdried over magnesium sulfate
14. concentrationconcentrated under reduced pressure
15. customThe residue was purified by silica gel column chromatography (ethyl acetate:hexane=1:9, volume ratio)

ORD-Eintrag

ord-9938c5c3c940443dba6d2ab343448f3d

Quelldatensatz

uspto-grants-2013_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08436043B2