3-Boc-2,2-dimethyloxazolidine-4-carboxaldehyde, (S)-(-)- → tert-butyl (4S)-4-[(1R)-1-hydroxyprop-2-en-1-yl]-2,2-dimethyl-1,3-oxazolidine-3-carboxylate

HRID 2200834Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 2200834
[C:1]([O:5][C:6]([N:8]1[C@H:12]([CH:13]=[O:14])[CH2:11][O:10][C:9]1([CH3:16])[CH3:15])=[O:7])([CH3:4])([CH3:3])[CH3:2].[CH:17]([Mg]Br)=[CH2:18]>C1COCC1>[C:1]([O:5][C:6]([N:8]1[C@H:12]([C@H:13]([OH:14])[CH:17]=[CH2:18])[CH2:11][O:10][C:9]1([CH3:16])[CH3:15])=[O:7])([CH3:4])([CH3:3])[CH3:2]

Komponenten

4

Edukt 2

HCID 1798243-Boc-2,2-dimethyloxazolidine-4-carboxaldehyde, (S)-(-)-HCID 178418507HCID 178418507, Verbindung

Produkt 1

HCID 10777541tert-butyl (4S)-4-[(1R)-1-hydroxyprop-2-en-1-yl]-2,2-dimethyl-1,3-oxazolidine-3-carboxylateAusbeute 62 %

Reagenzien, Katalysatoren, Lösungsmittel 1

HCID 8028TetrahydrofuranLösungsmittel2×

Reaktionsbedingungen

Temperatur
-78 °C

Versuchsvorschrift

To a −78° C. solution of (S)-Garner aldehyde (3, 7.0 g, 30.5 mmol) in dry THF (50 mL) under N2 was slowly added vinylmagnesium bromide (92 mL, 92 mmol, a 1 M solution in THF) via cannula. After the cloudy yellow solution was stirred for 2 h at −78° C., it was warmed to 0° C., and the reaction was quenched with saturated aqueous NH4Cl solution (60 mL). The product was extracted with Et2O (2×60 mL). The combined organic layers were washed with brine (60 mL), dried (Na2SO4), and concentrated. The mixture of erythro and threo diastereomers was separated by column chromatography by gravity (hexane/EtOAc 5:1) to afford 4 (4.8 g, 62%) and its C3-epimer 4a (0.8 g, 10.2%). Compound 4: [α]25D −37.7° (c 1.8, CHCl3); Rf 0.26 (EtOAc/hexane 1:3); 1H NMR (CDCl3) δ 1.48 (s, 3H), 1.50 (s, 9H), 1.58 (s, 3H), 3.91 (m, 2H), 3.98 (m, 1H), 4.25 (m, 1H), 4.39 (m, 1H), 5.24 (m, 1H), 5.38 (m, 1H), 5.85 (m, 1H); 13C NMR (CDCl3) δ 24.2, 26.3, 28.3, 61.8, 64.4, 73.3, 81.4, 94.4, 116.1, 117.8, 137.6, 155.0; ESI-HRMS [M+Na]+ C13H23NO4Na calcd for m/z 280.1525, found 280.1519.

Aufarbeitung

  1. customTo a −78° C.
  2. temperatureit was warmed to 0° C.
  3. customthe reaction was quenched with saturated aqueous NH4Cl solution (60 mL)
  4. extractionThe product was extracted with Et2O (2×60 mL)
  5. washThe combined organic layers were washed with brine (60 mL)
  6. dry with materialdried (Na2SO4)
  7. concentrationconcentrated
  8. additionThe mixture of erythro and threo diastereomers
  9. customwas separated by column chromatography by gravity (hexane/EtOAc 5:1)

Quellen und Nachweise

ORD-Eintrag
ord-049369a942de431fabd6a234eb0a5b15
Quelldatensatz
uspto-grants-2016_06
Patentnummer
US09359389B2

Notizen zur Reaktion

Wird geladen…