Reaktion #157856

Reaktionsgleichung

cyclobutanone

(5R)-5-[(E)-2-(5-Bromo-6-methoxypyridin-2-yl)-2-(4-tert-butylphenyl)ethenyl]-1-(2,4-dimethoxybenzyl)pyrrolidin-2-one

ammonium chloride

n-butyllithium

→

5-{2-(4-tert-butylphenyl)-2-[5-(1-hydroxycyclobutyl)-6-methoxypyridin-2-yl]ethenyl}-1-(2,4-dimethoxybenzyl)pyrrolidin-2-one

Lösungsmittel

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGThe mixture was stirred for further 30 minutes
2. 2
   Extraktionfollowed by extraction with ethyl acetate
3. 3
   TrocknenThe organic layer was dried over sodium sulfate
4. 4
   Sonstigethe solvent was evaporated under reduced pressure
5. 5
   SonstigeThe residue was purified by silica gel column chromatography (hexane:ethyl acetate=4:1→1:1)

Vorschrift

(5R)-5-[(E)-2-(5-Bromo-6-methoxypyridin-2-yl)-2-(4-tert-butylphenyl)ethenyl]-1-(2,4-dimethoxybenzyl)pyrrolidin-2-one obtained in Reference Example 4-42(1) (100 mg) was dissolved in tetrahydrofuran (5 mL), and n-butyllithium was added at −78° C. After stirring for 30 minutes, cyclobutanone was added dropwise. The mixture was stirred for further 30 minutes and then an ammonium chloride solution was added to the reaction solution, followed by extraction with ethyl acetate. The organic layer was dried over sodium sulfate, and then the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane:ethyl acetate=4:1→1:1) to give 5-{2-(4-tert-butylphenyl)-2-[5-(1-hydroxycyclobutyl)-6-methoxypyridin-2-yl]ethenyl}-1-(2,4-dimethoxybenzyl)pyrrolidin-2-one (EZ mixture) (35 mg).

Quelle