Ammonium Chloride → (R)-tert-butyl 2-(tert-butyldimethylsilyloxy)-4-(5-fluoro-2-methoxyphenyl)-4-hydroxybutylcarbamate

HRID 1426894Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 1426894
[Si:1]([O:8][C@H:9]1[CH2:13][N:12]([C:14]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[O:15])[C:11](=[O:21])[CH2:10]1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].[F:22][C:23]1[CH:24]=[CH:25][C:26]([O:31][CH3:32])=[C:27]([Mg]Br)[CH:28]=1.[BH4-].[Na+].[NH4+].[Cl-]>C1COCC1.CO>[Si:1]([O:8][C@H:9]([CH2:10][CH:11]([C:25]1[CH:24]=[C:23]([F:22])[CH:28]=[CH:27][C:26]=1[O:31][CH3:32])[OH:21])[CH2:13][NH:12][C:14](=[O:15])[O:16][C:17]([CH3:20])([CH3:19])[CH3:18])([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2]

Komponenten

7

Edukt 4

HCID 25517Ammonium ChlorideHCID 4311764Sodium borohydrideHCID 11220792(R)-1-Boc-4-[(tert-butyldimethylsilyl)oxy]pyrrolidin-2-oneHCID 178491810HCID 178491810, Verbindung

Produkt 1

HCID 67470707(R)-tert-butyl 2-(tert-butyldimethylsilyloxy)-4-(5-fluoro-2-methoxyphenyl)-4-hydroxybutylcarbamateAusbeute 57 %

Reagenzien, Katalysatoren, Lösungsmittel 2

HCID 887MethanolLösungsmittelHCID 8028TetrahydrofuranLösungsmittel2×

Reaktionsbedingungen

Temperatur
0 °C

Versuchsvorschrift

To a solution of (R)-tert-butyl 4-(tert-butyldimethylsilyloxy)-2-oxopyrrolidine-1-carboxylate (6.00 g, 19.0 mmol) in THF (36 mL) at 0° C. was added a 0.5 M solution of (5-fluoro-2-methoxyphenyl)magnesium bromide in THF (50.0 mL, 25.0 mmol). The resulting mixture was stirred at 0° C. for 30 minutes, then treated with MeOH (60 mL) and NaBH4 (0.966 g, 25.2 mmol). After stirring at 0° C. for an additional 30 minutes, the reaction mixture was poured into saturated aqueous NH4Cl (40 mL) and extracted with EtOAc (2×50 mL). The combined organic layers were washed with brine, dried over MgSO4, filtered, and concentrated under reduced pressure to give the crude material which was purified by silica column chromatography, eluting with 0-2% MeOH/DCM to afford (R)-tert-butyl 2-(tert-butyldimethylsilyloxy)-4-(5-fluoro-2-methoxyphenyl)-4-hydroxybutylcarbamate (which was assumed to be a mixture of the syn and anti isomers), (4.81 g, 57.0% yield). 1H NMR (CDCl3) δ 7.20 (m, 1H), 6.90 (m, 1H), 6.77 (m, 1H), 5.12 (m, 1H), 4.10 (m, 1H), 3.82 (m, 3H), 3.29 (m, 2H), 1.71-1.93 (m, 2H), 1.45 (s, 9H), 0.93 (d, 9H), 0.11-0.14 (m, 6H).

Aufarbeitung

  1. stirringAfter stirring at 0° C. for an additional 30 minutes
  2. extractionextracted with EtOAc (2×50 mL)
  3. washThe combined organic layers were washed with brine
  4. dry with materialdried over MgSO4
  5. filtrationfiltered
  6. concentrationconcentrated under reduced pressure
  7. customto give the crude material which
  8. customwas purified by silica column chromatography
  9. washeluting with 0-2% MeOH/DCM

Quellen und Nachweise

ORD-Eintrag
ord-a7681bb770df4267815091bb557307cc
Quelldatensatz
uspto-grants-2015_01
Patentnummer
US08933084B2

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