Hydrochloric Acid → Methyl 6-benzyloxy-2,4-dimethyl-3,5-dioxohexanoate

Temperatur

0 °C

A solution of methyl 2-methyl-3-oxopentanoate (13.05 g) in THF (100 ml) was added to a suspension of NaH (3.80 g) in THF (100 ml) at 0° C., and after stirring at 0° C. for 15 minutes, 1.63 M n-BuLi (58 ml) was added and the mixture was stirred at 0° C. for 20 minutes to prepare a light yellow dienolate. The reaction solution was cooled to −78° C., a solution of ethyl 2-(benzyloxy)acetate (17.56 g) in THF (30 ml) was added, and the mixture was stirred at −78° C. for 5 minutes and then at 0° C. for one hour. Diluted hydrochloric acid was poured into the reaction solution for quenching, and extraction was performed with AcOEt at near neutral. The organic layer was rinsed with saturated saline and dried with MgSO4, and then filtered and concentrated. The residue was purified by silica gel column chromatography (n-hexane/AcOEt=5/1→3/1) to obtain methyl 6-benzyloxy-2,4-dimethyl-3,5-dioxohexanoate.

1. stirringthe mixture was stirred at 0° C. for 20 minutes
2. customto prepare a light yellow dienolate
3. temperatureThe reaction solution was cooled to −78° C.
4. stirringthe mixture was stirred at −78° C. for 5 minutes
5. waitat 0° C. for one hour
6. customfor quenching
7. extractionextraction
8. washThe organic layer was rinsed with saturated saline
9. dry with materialdried with MgSO4
10. filtrationfiltered
11. concentrationconcentrated
12. customThe residue was purified by silica gel column chromatography (n-hexane/AcOEt=5/1→3/1)

ORD-Eintrag

ord-4ea07f82eb8d470ebf0593cc32acb591

Quelldatensatz

uspto-grants-2003_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06589984B1