Dimethylformamide → 2-Benzofurancarboxaldehyde

Temperature

-50 °C

2.18 g of benzofuran was dissolved in 40 ml of anhydrous tetrahydrofuran. Thereto was dropwise added 12.3 ml of 1.5 M n-butyllithium hexane solution, in 5 minutes with stirring at -50° C. The mixture was stirred at 0° C. for 30 minutes and then cooled to -60° C. Thereto was added 1.61 g of N,N-dimethylformamide, and the resulting mixture was stirred at room temperature for 1 hour. The solvent was removed by distillation under reduced pressure. The residue was mixed with 50 ml of ethyl acetate and 20 ml of water to dissolve the residue. The organic layer was separated, washed with an aqueous saturated sodium chloride solution, and dried over anhydrous magnesium sulfate. The solvent was removed by distillation under reduced pressure. The residue was purified by column chromatography (eluant: n-hexane/ethyl acetate =20/1 to 10/1) to obtain 1.70 g (yield: 63%) of 2-benzofurancarbaldehyde as a colorless oily material.

1. stirringThe mixture was stirred at 0° C. for 30 minutes
2. temperaturecooled to -60° C
3. stirringthe resulting mixture was stirred at room temperature for 1 hour
4. customThe solvent was removed by distillation under reduced pressure
5. additionThe residue was mixed with 50 ml of ethyl acetate and 20 ml of water
6. dissolutionto dissolve the residue
7. customThe organic layer was separated
8. washwashed with an aqueous saturated sodium chloride solution
9. dry with materialdried over anhydrous magnesium sulfate
10. customThe solvent was removed by distillation under reduced pressure
11. customThe residue was purified by column chromatography (eluant: n-hexane/ethyl acetate =20/1 to 10/1)

ORD record

ord-976e5eb212ef48bc92aa0493f3450e99

Source dataset

uspto-grants-1992_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05166204