Reaktion #165244
ord-b8f4346876a346f1a158cb653600e3d9
Reaktionsgleichung
Reagenzien
Lösungsmittel
Reaktionsbedingungen
Aufarbeitung
- 1workup.ADDITIONwas then added dropwise
- 2workup.STIRRINGstirred for 10 minutes at −78° C
- 3Sonstigewas allowed to room temperature
- 4Extraktionfollowed by extraction with ethyl acetate
- 5WaschenThe organic layer was washed with saturated aqueous sodium chloride
- 6Sonstigethe solvent was evaporated under a reduced pressure
- 7SonstigeThe residue was purified by NH silica gel column chromatography (ethyl acetate:heptane=1:5→1:1)
Vorschrift
To an anhydrous tetrahydrofuran (70.0 mL) solution of 2,5-dibromothiophene (5.00 g, 19.6 mmol) was added dropwise n-butyl lithium (2.55 M n-hexane solution, 7.69 mL, 19.6 mmol) on a dry ice-ethanol bath (−78° C.) under nitrogen atmosphere, which was stirred for 20 minutes at −78° C. p-Tolaldehyde (2.35 g, 19.6 mmol) was then added dropwise and stirred for 10 minutes at −78° C. The reaction mixture was allowed to room temperature and water was added, followed by extraction with ethyl acetate. The organic layer was washed with saturated aqueous sodium chloride, and the solvent was evaporated under a reduced pressure. The residue was purified by NH silica gel column chromatography (ethyl acetate:heptane=1:5→1:1) to obtain the title compound (4.30 g, 77.5%).