反应详情

Phenylrimethylammonium tribromide (2.0 g, 5.3 mmol) was added to a solution of 2-acetyl-7-methoxybenzofuran (1.0 g, 5.3 mmol) in anhydrous tetrahydrofuran (25 mL), and the mixture was stirred at room temperature for 4 hours. After the insoluble solid was filtered out, the filtrate was concentrated in vacuo to give a mixture including 2-bromoacetyl-7-methoxybenzofuran. Malonamamidine hydrochloride (1.5 g, 11 mmol) and potassium carbonate (1.5 g, 11 mmol) were added to a solution of this mixture in anhydrous N,N-dimethylformamide (40 mL) and the whole was stirred at 60° C. overnight. After cooling, the reaction mixture was diluted with water (200 mL), and the whole was extracted with ethyl acetate (100 mL, twice). The organic layer was washed with brine (100 mL) and dried over anhydrous magnesium sulfate. The solvent was removed in vacuo, and the obtained residue was purified by silica gel column chromatography to give the title reference compound (0.33 g) as a dark green solid (Yield 23%).

1. filtrationAfter the insoluble solid was filtered out
2. concentrationthe filtrate was concentrated in vacuo
3. customto give a mixture
4. stirringthe whole was stirred at 60° C. overnight
5. temperatureAfter cooling
6. extractionthe whole was extracted with ethyl acetate (100 mL
7. washThe organic layer was washed with brine (100 mL)
8. dry with materialdried over anhydrous magnesium sulfate
9. customThe solvent was removed in vacuo
10. customthe obtained residue was purified by silica gel column chromatography