Reaction #49190

Reaction equation

lithium borohydride

ethyl ester

1-(6-Benzyloxycarbonylamino-hexanoyl)-4-hydroxy-pyrrolidine-3-carboxylic acid ethyl ester

→

[6-(3-Hydroxy-4-hydroxymethyl-pyrrolidin-1-yl)-6-oxo-hexyl]-carbamic acid benzyl ester

Solvents

tetrahydrofuran

THF

MeOH CHCl3

Conditions

Workup

1. 1
   workup.ADDITIONAfter the addition the reaction mixture
2. 2
   Otherwas brought to room temperature
3. 3
   OtherThe 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
   Extractionwas extracted with dichloromethane (3×75 mL)
7. 7
   WashThe combined organic layer was washed with brine
8. 8
   Dryingdried over sodium sulfate
9. 9
   FiltrationOrganic layer was filtered
10. 10
    Otherevaporated to dryness
11. 11
    OtherCompound 63 was purified by column chromatography first
12. 12
    Washby eluting with dichloromethane/methanol (5%) (3.2 g, 92%)

Procedure

To the solution of lithium borohydride (0.305 g, 13 mmol) in anhydrous tetrahydrofuran (25 mL) was added a solution of ethyl ester 62 (3.74 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=0.4 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 63 was purified by column chromatography first by eluting with dichloromethane/methanol (5%) (3.2 g, 92%).

Source