Furfural → (5-Bromo-2-ethylphenyl)furan-2-ylmethanol

HRID 339463Notes

Reaction equation

HRID 339463 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([CH2:8][CH2:9]I)=[CH:4][CH:3]=1.C([Mg]Cl)(C)C.[O:16]1[CH:20]=[CH:19][CH:18]=[C:17]1[CH:21]=[O:22].[Cl-].[NH4+]>O1CCCC1>[Br:1][C:2]1[CH:7]=[CH:6][C:5]([CH2:8][CH3:9])=[C:4]([CH:21]([C:17]2[O:16][CH:20]=[CH:19][CH:18]=2)[OH:22])[CH:3]=1

Participants

6

Reactant 4

HCID 7362FurfuralHCID 25517Ammonium ChlorideHCID 197022221-Bromo-4-(2-iodoethyl)benzeneHCID 178418918HCID 178418918, compound

Product 1

HCID 58061495(5-Bromo-2-ethylphenyl)furan-2-ylmethanolYield 90%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
-70 °C

Procedure

4-Bromo-2-iodoethyl benzene (50.0 g, 160.8 mmol) is dissolved in anhydrous tetrahydrofuran (250 ml) and cooled to −70° C. under an atmosphere of nitrogen. Isopropylmagnesium chloride (2M solution in THF, 100 ml, 200 mmol) is added dropwise with vigorous stirring over 40 minutes, maintaining the internal temp below −60° C. by external cooling. When the addition is complete, the reaction is stirred at −70° C. for 20 minutes then allowed to warm to room temperature over 1 h 20 minutes. The reaction mixture is then cooled to −70° C. and a solution of 2-furaldehyde (16 ml, 18.6 g, 190 mmol) in tetrahydrofuran (50 ml) is added dropwise over 40 minutes. On completion of the addition, the reaction is allowed to warm to room temperature and stirred at room temperature for 3 hours. Saturated aqueous ammonium chloride solution (−500 ml) is added and the mixture is extracted into ethyl acetate. The organic solutions are combined, washed with brine, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue is further purified by column chromatography on silica gel to give (5-bromo-2-ethylphenyl)furan-2-ylmethanol (40.7 g).

Workup

  1. temperaturemaintaining the internal temp below −60° C. by external cooling
  2. additionWhen the addition
  3. stirringthe reaction is stirred at −70° C. for 20 minutes
  4. temperatureto warm to room temperature over 1 h 20 minutes
  5. temperatureThe reaction mixture is then cooled to −70° C.
  6. additionOn completion of the addition
  7. temperatureto warm to room temperature
  8. stirringstirred at room temperature for 3 hours
  9. extractionthe mixture is extracted into ethyl acetate
  10. washwashed with brine
  11. dry with materialdried over anhydrous magnesium sulfate
  12. concentrationconcentrated under reduced pressure
  13. customThe residue is further purified by column chromatography on silica gel

Sources & evidence

ORD record
ord-8c64dfb6a5324071b9acdc03df3cdb66
Source dataset
uspto-grants-2014_11
Patent number
US08895474B2

Reaction notes

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