7-Methylcoumarin → 7-(Bromomethyl)-2h-chromen-2-one

HRID 1090759Notes

Reaction equation

HRID 1090759 reaction equation
[CH3:1][C:2]1[CH:11]=[C:10]2[C:5]([CH:6]=[CH:7][C:8](=[O:12])[O:9]2)=[CH:4][CH:3]=1.[Br:13]N1C(=O)CCC1=O>C(Cl)(Cl)Cl>[Br:13][CH2:1][C:2]1[CH:11]=[C:10]2[C:5]([CH:6]=[CH:7][C:8](=[O:12])[O:9]2)=[CH:4][CH:3]=1

Participants

4

Reactant 2

HCID 171317-MethylcoumarinHCID 67184N-bromobutanimide

Product 1

HCID 2641197-(Bromomethyl)-2h-chromen-2-one

Reagents, catalysts & solvents 1

HCID 6212ChloroformSolvent

Procedure

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.

Workup

  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

Sources & evidence

ORD record
ord-a7fdfb5556684816b68121f54a0735f6
Source dataset
uspto-grants-1992_01
Patent number
US05082934

Reaction notes

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