2-Thiophenecarboxaldehyde → Thiophene, 2-(2-phenylethenyl)-

HRID 2081751Notes

Reaction equation

HRID 2081751 reaction equation
[Li][CH2:2][CH2:3][CH2:4]C.[S:6]1[CH:10]=[CH:9][CH:8]=[C:7]1[CH:11]=O.[CH2:13]1[CH2:17]O[CH2:15][CH2:14]1>>[C:13]1(/[CH:17]=[CH:11]/[C:7]2[S:6][CH:10]=[CH:9][CH:8]=2)[CH:4]=[CH:3][CH:2]=[CH:15][CH:14]=1

Participants

4

Conditions

Temperature
-78 °C

Procedure

Benzyldiethylphosphonate (5.7 g, 25 mmol) was dissolved in THF (50 mL) and cooled to -78° C. and nBuLi (2.5 M in hexane, 25 mmol) was added dropwise and the mixture was stirred for 30 min. Then a solution of thiophene-2-carboxaldehyde (2.8 g, 25 mmol) in THF (10 mL) was added dropwise at -78° C. The cold bath was removed and the reaction was warmed to room temperature, heated for 2 h at reflux and the reaction was then cooled and saturated aqueous NH4Cl was added. The mixture was diluted with water and extracted with ether. The organic extract was washed with brine, dried over MgSO4, filtered, and concentrated to provide a solid which was purified by recrystallization from hexane to give 2.6 g of intermediate.

Workup

  1. customThe cold bath was removed
  2. temperaturethe reaction was warmed to room temperature
  3. temperatureheated for 2 h
  4. temperatureat reflux
  5. temperaturethe reaction was then cooled
  6. additionsaturated aqueous NH4Cl was added
  7. additionThe mixture was diluted with water
  8. extractionextracted with ether
  9. extractionThe organic extract
  10. washwas washed with brine
  11. dry with materialdried over MgSO4
  12. filtrationfiltered
  13. concentrationconcentrated
  14. customto provide a solid which
  15. customwas purified by recrystallization from hexane

Sources & evidence

ORD record
ord-0423dced8b9145b5868e72e2f3a01599
Source dataset
uspto-grants-1993_02
Patent number
US05185363

Reaction notes

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