1,4-Dibromobenzene → HCID 14518743, compound

HRID 1723068Notes

Reaction equation

HRID 1723068 reaction equation
Br[C:2]1[CH:7]=[CH:6][C:5]([Br:8])=[CH:4][CH:3]=1.C([Li])CCC.[F:14][C:15]1[CH:24]=[CH:23][C:18]([C:19](=[O:22])[CH2:20]Cl)=[CH:17][CH:16]=1.[Cl-].[NH4+]>O1CCCC1>[F:14][C:15]1[CH:24]=[CH:23][C:18]([C:19]2([C:2]3[CH:7]=[CH:6][C:5]([Br:8])=[CH:4][CH:3]=3)[CH2:20][O:22]2)=[CH:17][CH:16]=1

Participants

6

Reactant 4

HCID 78041,4-DibromobenzeneHCID 25517Ammonium ChlorideHCID 1202482-Chloro-4'-fluoroacetophenoneHCID 178418339Butyllithium

Product 1

HCID 14518743HCID 14518743, compoundYield 45%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

Part A. A solution of 1,4-dibromobenzene (20.0 g, 0.08 mole) in tetrahydrofuran (200 mL) was cooled to -70+ and treated dropwise with n-butyllithium (1.6 M in hexane; 50 mL, 0.08 mole). The solution was stirred at this temperature for 60 minutes, then was treated dropwise with 4-fluorophenacyl chloride (13.8 g, 0.08 mole). The reaction was stirred at -70° overnight, then warmed to 0° for 3 hours. Saturated aqueous ammonium chloride was added, and the aqueous phase was separated. The aqueous phase was extracted with dichloromethane, and the combined organic phases were washed with saturated brine, then dried (Na2SO4) and concentrated under reduced pressure. The crude product was chromatographed on silica gel with 9:1 hexane/ethyl acetate to provide 2-(4-fluorophenyl)-2-(4-bromophenyl)-oxirane as an oil (10.5 g, 45% yield). NMR (CDCl3) 7.5-6.9(8H), 3.3-3.1(2H).

Workup

  1. stirringThe reaction was stirred at -70° overnight
  2. temperaturewarmed to 0° for 3 hours
  3. customthe aqueous phase was separated
  4. extractionThe aqueous phase was extracted with dichloromethane
  5. washthe combined organic phases were washed with saturated brine
  6. dry with materialdried (Na2SO4)
  7. concentrationconcentrated under reduced pressure
  8. customThe crude product was chromatographed on silica gel with 9:1 hexane/ethyl acetate

Sources & evidence

ORD record
ord-5402cfc0e5ba4907bf54f14d126e4a14
Source dataset
uspto-grants-1989_08
Patent number
US04859693

Reaction notes

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