反应详情

10 g (62.4 mmol) of 7-methyl-coumarin were suspended in 115 ml of carbon tetrachloride. After the addition of 12.2 g (68.7 mmol) of N-bromosuccinimide and 0.122 g (0.5 mmol) of benzoyl peroxide the reaction mixture was boiled under reflux for 7 hours. After cooling to room temperature the mixture was filtered. The residue was washed in succession with carbon tetrachloride and a small amount of diethyl ether and subsequently digested in 500 ml of water. The crude product was filtered off, dried and recrystallized from about 150 ml of acetone. After drying in a water-jet vacuum at 60° C. there were obtained 11 g of 7-bromomethyl-2H-1-benzopyran-2-one as white crystals.

1. temperatureunder reflux for 7 hours
2. filtrationwas filtered
3. washThe residue was washed in succession with carbon tetrachloride
4. filtrationThe crude product was filtered off
5. customdried
6. customrecrystallized from about 150 ml of acetone
7. dry with materialAfter drying in a water-jet vacuum at 60° C.