Phosphorus oxychloride → 4-Benzyloxy-benzofuran-7-carbaldehyde

Participants

Reaction Conditions

Reaction Steps

Dry N,N-dimethylformamide (12.1 g, 166 mmol) was added dropwise with stirring and cooling under an argon atmosphere to phosphorous oxychloride (11.4 g, 75 mmol) at such a rate that the temperature did not exceed 10° C. After 30 min at 10° C., a solution of 4-benzyloxy-benzofuran (9.3 g, 41 mmol) in N,N-dimethylformamide (9 ml) was added dropwise within 30 min. The reaction mixture was stirred 30 min at ambient temperature and then continuously heated to 100° C. After 10 min at 100° C. the mixture was heated at 85° C. for 3 h, cooled to 10° C., neutralized with 25% aqueous sodium acetate, with cooling, and extracted with diethyl ether. The extract was washed with saturated aqueous sodium bicarbonate and water and dried over sodium sulfate. Removal of the solvent under reduced pressure gave a brown oil which was purified by column chromatography (silica gel, hexane/AcOEt=19/1) to give 1.8 g (7 mmol, 17%) of the title compound as yellow oil.

Provenance & Evidence