Benzyl Bromide → 4-Benzyloxy-5-(4-fluorophenoxy)-1-pentene

HRID 328792Notes

Reaction equation

HRID 328792 reaction equation
[F:1][C:2]1[CH:14]=[CH:13][C:5]([O:6][CH2:7][CH:8]([OH:12])[CH2:9][CH:10]=[CH2:11])=[CH:4][CH:3]=1.[H-].[Na+].[H][H].[CH2:19](Br)[C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1>CN(C)C=O.CO.O.CCCCCC>[CH2:19]([O:12][CH:8]([CH2:7][O:6][C:5]1[CH:13]=[CH:14][C:2]([F:1])=[CH:3][CH:4]=1)[CH2:9][CH:10]=[CH2:11])[C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1

Participants

9

Reactant 4

HCID 7498Benzyl BromideHCID 24758Sodium hydrideHCID 213175735-(4-Fluorophenoxy)-1-penten-4-olHCID 178418361HCID 178418361, compound

Product 1

HCID 213176584-Benzyloxy-5-(4-fluorophenoxy)-1-penteneYield 92%

Reagents, catalysts & solvents 4

HCID 887MethanolCatalystHCID 962WaterSolventHCID 6228DimethylformamideSolvent3×HCID 8058HexaneSolvent

Procedure

A solution of 5-(4-fluorophenoxy)-1-penten-4-ol (9.81 g., 50 mmoles) in dimethylformamide (15 ml.) is added dropwise to a suspension of hexane (2 × 10 ml.) prewashed sodium hydride (50% oil dispersion, 2.64 g., 55mmoles) in dimethylformamide (45 ml.). The resulting mixture is stirred until gas evolution ceases. (A few drops of methanol may be needed to initiate the evolution of hydrogen). The reaction mixture is chilled in an ice bath and treated with a solution of benzyl bromide (10.30 g., 60 mmoles) in dimethylformamide (10 ml.). The reaction mixture is then stirred at room temperature overnight (ca. 16 hours), and then heated on a steam bath for 1 hour. The reaction mixture is diluted with cold water (50 ml.), and extracted with ether four times. The combined extracts are washed with 2N hydrochloric acid and saturated brine and finally dried over anhydrous magnesium sulfate. After the removal of the solvent, the oil residue is vacuum distilled at 112°~6° C./0.025 mm. to give the title compound (13.1 g., 45.7 mmoles, 92%). ir (neat) 3.3~3.5, 6.08, 6.21, 6.65, 8.01, 8.28, 9.13, 10.90, 12.10, 13.18, 13.60, 14.40μ; pmr (CCl4)δ 2.37 (2H, t, J-5Hz), 3.5-4.0 (3H, m), 4.57 (2H, s), 4.8-5.05 (1H, m), 5.05-5.25 (1H, m), 5.4-6.2 (1H, m), 6.6-7.1 (4H, m), 7.19 (5H, s).

Workup

  1. temperatureThe reaction mixture is chilled in an ice bath
  2. stirringThe reaction mixture is then stirred at room temperature overnight (ca. 16 hours)
  3. temperatureheated on a steam bath for 1 hour
  4. extractionextracted with ether four times
  5. washThe combined extracts are washed with 2N hydrochloric acid and saturated brine
  6. dry with materialfinally dried over anhydrous magnesium sulfate
  7. customAfter the removal of the solvent
  8. distillationdistilled at 112°~6° C./0.025 mm

Sources & evidence

ORD record
ord-229575318a9b47ae83ab0fb29b497969
Source dataset
uspto-grants-1977_04
Patent number
US04018802

Reaction notes

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