Triethylamine → 3-Acetyl-6-bromo-4-phenylisochromen-1-one

Participants

Reaction Steps

[Step 1] To a solution of 6-bromo-4-phenyl-3-isocoumarincarboxylic acid (10.3 g), 2,2-dimethyl-[1,3]dioxane-4,6-dione (4.76 g), dimethylpyridin-4-yl-amine (5.50 g) and triethylamine (6.3 ml) in dichloromethane (100 ml) was added 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (8.6 g) at room temperature and the mixture was stirred at room temperature for 15 hrs. The mixture was diluted with dichloromethane, washed with 1N hydrochloric acid and saturated brine and dried by adding sodium sulfate. The solvent was evaporated under reduced pressure and the obtained residue dissolved in water (200 ml) and acetic acid (100 ml) and the mixture was heated under reflux for 10 hrs. The solvent was evaporated under reduced pressure, water was added and the mixture was extracted with ethyl acetate. The extract was washed with saturated sodium hydrogen carbonate solution and saturated brine and dried by adding sodium sulfate. The obtained residue was crystallized from diisopropyl ether to give 3-acetyl-6-bromo-4-phenyl-isochromen-1-one (8.29 g, 81%).

Provenance & Evidence