Reaktion #87986

Reaktionsgleichung

methyl 7-((5R)-3,3-difluoro-5-((E)-4-methyl-3-oxooct-1-en-6-yn-1-yl)-2-oxopyrrolidin-1-yl)heptanoate

cerium chloride heptahydrate

Sodium borohydride

→

title compound

Ausbeute 87.6%

methyl 7-((5R)-3,3-difluoro-5-((E)-3-hydroxy-4-methyloct-1-en-6-yn-1-yl)-2-oxopyrrolidin-1-yl)heptanoate

Ausbeute 87.6%

Lösungsmittel

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeTo a −40° C.
2. 2
   workup.STIRRINGthe reaction was stirred for 3 hours
3. 3
   Sonstigequenched with equal parts water and saturated ammonium chloride
4. 4
   Temperaturwarmed to room temperature
5. 5
   ExtraktionThe reaction mixture was extracted with ethyl acetate
6. 6
   TrocknenThe combined organic phase was dried over sodium sulfate
7. 7
   Einengenconcentrated to a cloudy white oil
8. 8
   SonstigeThe residue was purified by silica gel chromatography
9. 9
   WaschenElution with methanol-dichloromethane (1:200 v:v)

Vorschrift

To a −40° C. solution consisting of methyl 7-((5R)-3,3-difluoro-5-((E)-4-methyl-3-oxooct-1-en-6-yn-1-yl)-2-oxopyrrolidin-1-yl)heptanoate (76 mg, 0.20 mmol) in methanol (5 mL) was added cerium chloride heptahydrate (75 mg, 0.20 mmol) in one portion. The reaction mixture was stirred for 15 minutes, and cooled to −78° C. for 20 minutes. Sodium borohydride (15 mg, 0.40 mmol) was added and the reaction was stirred for 3 hours, quenched with equal parts water and saturated ammonium chloride and warmed to room temperature. The reaction mixture was extracted with ethyl acetate. The combined organic phase was dried over sodium sulfate and concentrated to a cloudy white oil. The residue was purified by silica gel chromatography. Elution with methanol-dichloromethane (1:200 v:v) to afford the title compound (70 mg) as a clear oil. Rf 0.50 (solvent system: 5:95 v/v methanol:dichloromethane).

Quelle