反应详情

To 50 ml of chloroform was added 7-methylcoumarin (10 g, 62.4 mmol) and N-bromosuccinimide (11.1 g, 62.4 mmol). The suspension was then refluxed for 24 hours at which time a clear solution resulted. Reflux was continued for five days. At this point a spherical lump of crystals had formed. The reaction mixture was cooled to room temperature and was then placed in the refrigerator at 0° C. for 24 hrs. The crystals were collected by filtration and washed with a small amount of cold chloroform. After brief evacuation to remove chloroform, the crystals were dissolved in a minimum amount of boiling acetone and allowed to crystallize for several days. The crystals were collected by filtration and washed with a little cold acetone. After drying in vacuo the yield was , 7.15 g (48% of theory). The melting point was 179.5°-181.5° C.

1. temperatureThe suspension was then refluxed for 24 hours at which time a clear solution
2. customresulted
3. temperatureReflux
4. customAt this point a spherical lump of crystals had formed
5. waitwas then placed in the refrigerator at 0° C. for 24 hrs
6. filtrationThe crystals were collected by filtration
7. washwashed with a small amount of cold chloroform
8. customAfter brief evacuation to remove chloroform
9. dissolutionthe crystals were dissolved in a minimum amount of boiling acetone
10. customto crystallize for several days
11. filtrationThe crystals were collected by filtration
12. washwashed with a little cold acetone
13. customAfter drying in vacuo the yield