Boron trifluoride etherate → (R)-1-(N-Benzyloxycarbonylpyrrolidin-2-yl)-3-hydroxypropene

HRID 744155Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 744155
[CH2:1]([O:8][C:9]([N:11]1[CH2:15][CH2:14][CH2:13][C@@H:12]1[CH:16]=[CH:17][C:18](OCC)=[O:19])=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.B(F)(F)F.CCOCC.[H-].C([Al+]CC(C)C)C(C)C>O1CCCC1>[CH2:1]([O:8][C:9]([N:11]1[CH2:15][CH2:14][CH2:13][C@@H:12]1[CH:16]=[CH:17][CH2:18][OH:19])=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Komponenten

5

Edukt 3

HCID 8000Boron trifluoride etherateHCID 21225700DiisobutylaluminumhydrideHCID 53843981(R)-ethyl 3-(N-benzyloxycarbonylpyrrolidin-2-yl)-2-propenoate

Produkt 1

HCID 54485243(R)-1-(N-Benzyloxycarbonylpyrrolidin-2-yl)-3-hydroxypropeneAusbeute 52,6 %

Reagenzien, Katalysatoren, Lösungsmittel 1

HCID 8028TetrahydrofuranLösungsmittel

Versuchsvorschrift

To a stirred solution of (R)-ethyl 3-(N-benzyloxycarbonylpyrrolidin-2-yl)-2-propenoate (574 g) in tetrahydrofuran (5.7 L) at about -78° C. was added boron trifluoride etherate (295.4 g) and then diisobutylaluminum hydride (1.5M in toluene, 3.91 L, 3.1 eq) added (over two hours) maintaining the temperature below -62° C. The resulting solution was stirred (between -78° and -62° C.) for three hours and then quenched into aqueous citric acid solution (2 kg citric acid in 5 L water plus 4 L ice) over about 40 minutes. The phases were separated and the aqueous phase extracted with ethyl acetate (2×2.1 L). The combined organic solution was dried (over magnesium sulphate) and evaporated, then the residual oil purified by chromatography through silica gel, eluting with mixed ethyl acetate/hexane (9:1 to 4:1) to give the title compound as an oil (260 g), as produced in Example 12A (as an alternative, the residual oil can be purified by chromatography through silica gel eluting with ethyl acetate:hexane (1:1)).

Aufarbeitung

  1. temperaturemaintaining the temperature below -62° C
  2. customquenched into aqueous citric acid solution (2 kg citric acid in 5 L water plus 4 L ice) over about 40 minutes
  3. customThe phases were separated
  4. extractionthe aqueous phase extracted with ethyl acetate (2×2.1 L)
  5. dry with materialThe combined organic solution was dried (over magnesium sulphate)
  6. customevaporated
  7. customthe residual oil purified by chromatography through silica gel
  8. washeluting with mixed ethyl acetate/hexane (9:1 to 4:1)

Quellen und Nachweise

ORD-Eintrag
ord-864d11da6cd942458c7b2d4a00441500
Quelldatensatz
uspto-grants-1996_09
Patentnummer
US05559129

Notizen zur Reaktion

Wird geladen…