반응 #428552

반응 방정식

1,3,5-Trioxane

DIPEA

Intermediate ( 2a )

(S)-4-Benzyl-3-(4-methylpentanoyl)oxazolidin-2-one

→

intermediate ( 2b )

수율 98.3%

(S)-4-Benzyl-3-((R)-2-hydroxymethyl-4-methylpentanoyl)oxazolidin-2-one

수율 98.3%

용매

DCM

DCM

DCM

DCM

반응 조건

후처리

1. 1
   workup.STIRRINGstirred for 15 minutes
2. 2
   workup.STIRRINGthe mixture was stirred for 75 minutes
3. 3
   workup.STIRRINGthe mixture stirred at 0° C. for 5 hours
4. 4
   기타The reaction was then quenched with 250 mL of saturated ammonium chloride
5. 5
   workup.ADDITIONWater and DCM were added
6. 6
   추출the aqueous phase was extracted twice more with DCM
7. 7
   건조dried over MgSO4
8. 8
   여과filtered
9. 9
   농축concentrated
10. 10
    기타The resulting material was purified by silica gel chromatography (0-60% EtOAc:hexanes)

실험 절차

Intermediate (2a) (14.5 g, 46.3 mmol) was dissolved in DCM (151 mL, 2.4 mol) and stirred at 0° C. under nitrogen. 1 M titanium tetrachloride in DCM (48.6 mL) was added and stirred for 15 minutes. DIPEA (8.9 mL, 51.0 mmol) was added dropwise at 0° C. and the mixture was stirred for 75 minutes. 1,3,5-Trioxane (4.6 g, 51.0 mmol) in DCM (30 mL) was then added. After 10 minutes a second equivalent of 1 M titanium tetrachloride in DCM (48.6 mL) was added and the mixture stirred at 0° C. for 5 hours. The reaction was then quenched with 250 mL of saturated ammonium chloride. Water and DCM were added, and the aqueous phase was extracted twice more with DCM. The organic layers were combined, dried over MgSO4, filtered and concentrated. The resulting material was purified by silica gel chromatography (0-60% EtOAc:hexanes) to provide intermediate (2b) (13.9 g).

출처