Diethyl Ether → 7-Bromo-4-fluoro-2-methylbenzofuran

HRID 618720Notes

Reaction equation

HRID 618720 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([F:8])=[CH:4][C:3]=1[O:9][CH2:10][C:11]#C.[F-].[Cs+].[CH2:15](OCC)C>CCN(C1C=CC=CC=1)CC>[Br:1][C:2]1[C:3]2[O:9][C:10]([CH3:11])=[CH:15][C:4]=2[C:5]([F:8])=[CH:6][CH:7]=1

Participants

5

Reactant 3

HCID 3283Diethyl EtherHCID 25953Cesium fluorideHCID 224828471-Bromo-4-fluoro-2-[(prop-2-yn-1-yl)oxy]benzene

Product 1

HCID 218483217-Bromo-4-fluoro-2-methylbenzofuranYield 89%

Reagents, catalysts & solvents 1

HCID 7061N,N-DiethylanilineSolvent

Procedure

A suspension of 57 g (250 mmol) of 1-bromo-4-fluoro-2-prop-2-ynyloxy-benzene and 53 g (350 mmol) of caesium fluoride in 400 ml of diethylaniline was heated at reflux in a metal bath for 4 hours. After cooling to room temperature 1500 ml of diethyl ether were added thereto and the insoluble constituents were filtered off. The diethyl ether phase was washed three times with 600 ml of 1N hydrochloric acid, dried over sodium sulfate and concentrated in a vacuum. The crude product obtained was purified by column chromatography on silica gel (hexane). 51.4 g (89%) of 7-bromo-4-fluoro-2-methylbenzofuran were obtained as a pale yellow oil.

Workup

  1. temperaturewas heated
  2. temperatureat reflux in a metal bath for 4 hours
  3. additionwere added
  4. filtrationthe insoluble constituents were filtered off
  5. washThe diethyl ether phase was washed three times with 600 ml of 1N hydrochloric acid
  6. dry with materialdried over sodium sulfate
  7. concentrationconcentrated in a vacuum
  8. customThe crude product obtained
  9. customwas purified by column chromatography on silica gel (hexane)

Sources & evidence

ORD record
ord-ee0faf0845964a68bfd79996e2fda81f
Source dataset
uspto-grants-1999_09
Patent number
US05955495

Reaction notes

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