Isobutyrophenone → Ethyl 4-methyl-3-phenylpentanoate

Under a nitrogen atmosphere, ethyl trimethylsilylethylacetate (5.19 g) was added at −78° C. to a solution of a lithium diisopropylamide/tetrahydrofuran solution (1.5 M, 21.6 mL) added to tetrahydrofuran solution (100 mL). After 20 minutes, a tetrahydrofuran solution (10 ml) of isobutyrophenone (4.0 g) was added thereto, and the temperature of the mixture was naturally returned to room temperature. After stirring 18 hours, sodium bisulfate monohydrate (0.6 g) was added and the mixture was stirred. Further, after 10 minutes, the organic layer was separated by adding a 0.2N hydrochloric acid solution (250 mL) and ethyl acetate (200 mL) thereto. The resulting organic layer was washed with water and brine, and dried over anhydrous magnesium sulfate. After filtering off the drying agent, the mixture was evaporated. 756 Mg among the resulting crude product (7.9 g) was dissolved in methanol (5 mL), a catalytic amount of 10% palladium carbon (9.5 mg) was added, and the mixture was stirred under hydrogen atmosphere. After 4 hours, the catalyst was filtered off, and the filtrate was concentrated. The resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate system), to give the title compound as a colorless oil (350 mg).

1. customwas naturally returned to room temperature
2. stirringthe mixture was stirred
3. waitFurther, after 10 minutes
4. customthe organic layer was separated
5. additionby adding a 0.2N hydrochloric acid solution (250 mL) and ethyl acetate (200 mL)
6. washThe resulting organic layer was washed with water and brine
7. dry with materialdried over anhydrous magnesium sulfate
8. filtrationAfter filtering off the drying agent
9. customthe mixture was evaporated
10. dissolution756 Mg among the resulting crude product (7.9 g) was dissolved in methanol (5 mL)
11. additiona catalytic amount of 10% palladium carbon (9.5 mg) was added
12. stirringthe mixture was stirred under hydrogen atmosphere
13. waitAfter 4 hours
14. filtrationthe catalyst was filtered off
15. concentrationthe filtrate was concentrated
16. customThe resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate system)

ORD-Eintrag

ord-cb9c73b52b334282a9d8a990b46be56d

Quelldatensatz

uspto-grants-2005_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06906072B1