Reaktion #49199

Reaktionsgleichung

lithium borohydride

ethyl ester

4-Hydroxy-pyrrolidine-1,3-dicarboxylic acid 1-benzyl ester 3-ethyl ester

→

3-Hydroxy-4-hydroxymethyl-pyrrolidine-1-carboxylic acid benzyl ester

Lösungsmittel

tetrahydrofuran

THF

MeOH CHCl3

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONAfter the addition the reaction mixture
2. 2
   Sonstigewas brought to room temperature
3. 3
   SonstigeThe reaction mixture was evaporated to dryness
4. 4
   workup.ADDITIONTo the residue 3N HCl (40 mL) was added slowly
5. 5
   workup.STIRRINGAfter stirring for 30 mins the product
6. 6
   Extraktionwas extracted with dichloromethane (3×75 mL)
7. 7
   WaschenThe combined organic layer was washed with brine
8. 8
   Trocknendried over sodium sulfate
9. 9
   FiltrationOrganic layer was filtered
10. 10
    Sonstigeevaporated to dryness
11. 11
    SonstigeCompound 74 was purified by column chromatography first
12. 12
    Waschenby eluting with dichloromethane/methanol (5%) (1.98 g, 85%)

Vorschrift

To the solution of lithium borohydride (0.305 g, 13 mmol) in anhydrous tetrahydrofuran (25 mL) was added a solution of ethyl ester 73 (2.69 g, 9.2 mmol) in THF (25 mL) over a period of 30 mins at 0° C. After the addition the reaction mixture was brought to room temperature and stirred further under argon. The completion of the reaction was ascertained by TLC after 4 h. (Rf=0.3 in 10% MeOH/CHCl3). The reaction mixture was evaporated to dryness and cooled to 0° C. To the residue 3N HCl (40 mL) was added slowly. After stirring for 30 mins the product was extracted with dichloromethane (3×75 mL). The combined organic layer was washed with brine and dried over sodium sulfate. Organic layer was filtered and evaporated to dryness. Compound 74 was purified by column chromatography first by eluting with dichloromethane/methanol (5%) (1.98 g, 85%).

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