Sodium hydride → cis-1-(2-Fluorobenzyloxy)-cyclopentan-2-ol

HRID 894151

Reaktionsgleichung

Reaktionsgleichung von HRID 894151
[C@@H:1]1([OH:7])[CH2:5][CH2:4][CH2:3][C@@H:2]1[OH:6].[H-].[Na+].[H][H].[F:12][C:13]1[CH:20]=[CH:19][CH:18]=[CH:17][C:14]=1[CH2:15]Br>O1CCOCC1.CO>[F:12][C:13]1[CH:20]=[CH:19][CH:18]=[CH:17][C:14]=1[CH2:15][O:6][C@@H:2]1[CH2:3][CH2:4][CH2:5][C@@H:1]1[OH:7]

Komponenten

7

Edukt 4

HCID 24758Sodium hydrideHCID 67968alpha-Bromo-o-fluorotolueneHCID 2733293(1R,2S)-cyclopentane-1,2-diolHCID 178418361HCID 178418361, Verbindung

Produkt 1

HCID 53647391cis-1-(2-Fluorobenzyloxy)-cyclopentan-2-olAusbeute 46,1 %

Reagenzien, Katalysatoren, Lösungsmittel 2

HCID 887MethanolLösungsmittelHCID 312751,4-DioxaneLösungsmittel2×

Reaktionsbedingungen

Temperatur
70 °C

Versuchsvorschrift

19.4 g (0.19 mol) of cis-1,2-cyclopentanediol were added dropwise to a suspension of 4.8 g (0.2 mol) of sodium hydride (6.0 g of 80% pure sodium hydride in toluene) in 200 ml of dioxan at 5° C. under a nitrogen atmosphere, whilst stirring. After the evolution of hydrogen had ended, the mixture was warmed to 70° C. for 45 minutes and then brought to room temperature and 359 g (0.19 mol) of 2-fluorobenzyl bromide in absolute dioxan were added. After stirring the mixture for 30 minutes, it was heated to the boil for a further 4 hours and cooled and about 10 ml of methanol were added. The mixture was concentrated to dryness on a rotary evaporator, the residue was taken up in water and the mixture was extracted with methylene chloride. The organic phase was dried over sodium sulphate and filtered and the solvent was stripped off from the filtrate on a rotary evaporator. The oily residue was distilled under an oil pump vacuum. 18.4 g (46% of theory) of cis-1-(2-fluorobenzyloxy)-cyclopentan-2-ol of boiling point 95°-100° C./0.1 mm Hg were obtained.

Aufarbeitung

  1. custombrought to room temperature
  2. stirringAfter stirring the mixture for 30 minutes
  3. temperatureit was heated to the boil for a further 4 hours
  4. temperaturecooled
  5. concentrationThe mixture was concentrated to dryness on a rotary evaporator
  6. extractionthe mixture was extracted with methylene chloride
  7. dry with materialThe organic phase was dried over sodium sulphate
  8. filtrationfiltered
  9. customthe solvent was stripped off from the filtrate on a rotary evaporator
  10. distillationThe oily residue was distilled under an oil pump vacuum

Quellen und Nachweise

ORD-Eintrag
ord-a7b7b0b0759a4810b0febff831ab4776
Quelldatensatz
uspto-grants-1981_08
Patentnummer
US04282388

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