1,3,5-Tribromobenzene → 3,5-Dibromo-alpha-(4-fluorophenyl)benzenemethanol

HRID 53323

Reaction equation

HRID 53323 reaction equation
C([Li])CCC.Br[C:7]1[CH:12]=[C:11]([Br:13])[CH:10]=[C:9]([Br:14])[CH:8]=1.[F:15][C:16]1[CH:23]=[CH:22][C:19]([CH:20]=[O:21])=[CH:18][CH:17]=1>CCCCCC.CCOCC>[Br:14][C:9]1[CH:8]=[C:7]([CH:20]([C:19]2[CH:22]=[CH:23][C:16]([F:15])=[CH:17][CH:18]=2)[OH:21])[CH:12]=[C:11]([Br:13])[CH:10]=1

Participants

6

Reactant 3

HCID 122791,3,5-TribromobenzeneHCID 680234-FluorobenzaldehydeHCID 178418339Butyllithium

Product 1

HCID 199623533,5-Dibromo-alpha-(4-fluorophenyl)benzenemethanolYield 87.2%

Reagents, catalysts & solvents 2

HCID 3283Diethyl EtherSolventHCID 8058HexaneSolvent

Procedure

A 2.5M solution of n-butyllithium in hexane (44.0 ml) was added dropwise to a stirred suspension of 1,3,5-tribromobenzene (31.5 g) in dry ether (1000 ml) at -78° C. under an atmosphere of dry nitrogen. The resulting mixture was stirred at this temperature for 30 minutes and the 4-fluorobenzaldehyde (13.65 g) was added dropwise. Stirring at -78° C. was continued for a further 30 minutes and then the reaction was quenched by the addition of water. The temperature was allowed to reach room temperature and the organic layer was separated and dried (MgSO4). Evaporation of the solvent gave an oil which was chromatographed on silica gel. The column was eluted with dichloromethane/hexane (1:5), gradually increasing the ratio of solvents to 2:3. The product fractions were combined, evaporated and the residue was triturated with hexane to give the title compound (31.42 g), m.p. 92°-93° C. Found: C,43.75; H,2.43. C13H9Br2OF requires C,43.37; H,2.52%.

Workup

  1. stirringStirring at -78° C.
  2. waitwas continued for a further 30 minutes
  3. customthe reaction was quenched by the addition of water
  4. customto reach room temperature
  5. customthe organic layer was separated
  6. dry with materialdried (MgSO4)
  7. customEvaporation of the solvent
  8. customgave an oil which
  9. customwas chromatographed on silica gel
  10. washThe column was eluted with dichloromethane/hexane (1:5)
  11. temperaturegradually increasing the ratio of solvents to 2:3
  12. customevaporated
  13. customthe residue was triturated with hexane

Sources & evidence

ORD record
ord-b4e48c84258f420eb82815a11ed661a9
Source dataset
uspto-grants-1997_04
Patent number
US05618941

Linked notes

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