Water → 5-Methoxy-3-methyl-1-benzofuran-2-carbaldehyde

To a solution (100 mL) of methyl 5-methoxy-3-methyl-1-benzofuran-2-carboxylate (5.00 g) in tetrahydrofuran was added lithium aluminum hydride (862 mg) at 0° C., and the mixture was stirred for 1.5 hr. Water (860 μL) was added to quench the reaction, 1N aqueous sodium hydroxide solution (860 μL) was added, and the mixture was stirred at room temperature for 1 hr. The resulting insoluble material was filtered off, and the filtrate was concentrated under reduced pressure to give a pale-yellow solid. To a solution of the obtained solid in tetrahydrofuran (80 mL) was added active manganese dioxide (21.2 g), and the mixture was stirred at 50° C. overnight. Manganese dioxide was filtered off, and the filtrate was concentrated under reduced pressure to give the title object compound (3.41 g, 79%) as a brown solid.

1. customto quench
2. customthe reaction, 1N aqueous sodium hydroxide solution (860 μL)
3. additionwas added
4. stirringthe mixture was stirred at room temperature for 1 hr
5. filtrationThe resulting insoluble material was filtered off
6. concentrationthe filtrate was concentrated under reduced pressure
7. customto give a pale-yellow solid
8. stirringthe mixture was stirred at 50° C. overnight
9. filtrationManganese dioxide was filtered off
10. concentrationthe filtrate was concentrated under reduced pressure

ORD-Eintrag

ord-373e48e3eac844048cf3f8866d6fd109

Quelldatensatz

uspto-grants-2013_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08436043B2