N-bromobutanimide → Methyl 4-bromomethyl-2,6-diacetoxybenzoate

HRID 1274530Notes

Reaction equation

HRID 1274530 reaction equation
[CH3:1][C:2]1[CH:11]=[C:10]([O:12][C:13](=[O:15])[CH3:14])[C:5]([C:6]([O:8][CH3:9])=[O:7])=[C:4]([O:16][C:17](=[O:19])[CH3:18])[CH:3]=1.[Br:20]N1C(=O)CCC1=O>C(Cl)(Cl)(Cl)Cl.C(OOC(=O)C1C=CC=CC=1)(=O)C1C=CC=CC=1.BrN1C(=O)CCC1=O>[Br:20][CH2:1][C:2]1[CH:3]=[C:4]([O:16][C:17](=[O:19])[CH3:18])[C:5]([C:6]([O:8][CH3:9])=[O:7])=[C:10]([O:12][C:13](=[O:15])[CH3:14])[CH:11]=1

Participants

6

Reactant 2

HCID 67184N-bromobutanimideHCID 22121076Methyl 4-methyl-2,6-diacetoxybenzoate

Product 1

HCID 22556044Methyl 4-bromomethyl-2,6-diacetoxybenzoateYield 62%

Reagents, catalysts & solvents 3

HCID 7187Benzoyl PeroxideCatalystHCID 67184N-bromobutanimideCatalystHCID 5943Carbon TetrachlorideSolvent

Procedure

Methyl 4-methyl-2,6-diacetoxybenzoate (14.9 grams, 56.0 mmoles) was dissolved in carbon tetrachloride (200 mL), and N-bromosuccinimide (11.1 grams, 62.2 mmoles) and benzoyl peroxide (0.2 grams, 0.8 mmoles) were added. The mixture was refluxed under nitrogen. After 3.5 hours, an additional portion (0.2 grams) of N-bromosuccinimide was added. Reflux was continued for an additional hour. The reaction mixture was cooled to room temperature and then in ice for 1 hour, and the solid removed by filtration. The filtrate was evaporated to dryness. Hexanes (250 mL) was added to the residue, and the mixture was boiled until dissolution was obtained. The hexanes solution was concentrated to about 75 mL when a solid just began to precipitate. The mixture was heated to dissolve the solid, and the solution was allowed to cool slowly to room temperature. White crystals formed slowly, and the mixture was chilled in ice for 2 hours to complete crystallization. The solid was filtered, washed with cold hexanes (100 mL), and dried in vacuo to afford 11.9 grams (62% yield) of methyl 4-bromomethyl-2,6-diacetoxy-benzoate (m.p. 93-95° C., open capillary, uncorrected). The product was contaminated with a small amount of methyl 2,6-diacetoxy-4-dibromomethylbenzoate, which did not interfere with subsequent reactions.

Workup

  1. temperatureThe mixture was refluxed under nitrogen
  2. temperatureReflux
  3. waitwas continued for an additional hour
  4. waitin ice for 1 hour
  5. customthe solid removed by filtration
  6. customThe filtrate was evaporated to dryness
  7. additionHexanes (250 mL) was added to the residue
  8. dissolutionthe mixture was boiled until dissolution
  9. customwas obtained
  10. concentrationThe hexanes solution was concentrated to about 75 mL when a solid
  11. customto precipitate
  12. temperatureThe mixture was heated
  13. dissolutionto dissolve the solid
  14. temperatureto cool slowly to room temperature
  15. customWhite crystals formed slowly
  16. temperaturethe mixture was chilled in ice for 2 hours
  17. customcrystallization
  18. filtrationThe solid was filtered
  19. washwashed with cold hexanes (100 mL)
  20. customdried in vacuo

Sources & evidence

ORD record
ord-03a25a1a7e1641ccb74efa31f4c5409b
Source dataset
uspto-grants-2000_12
Patent number
US06156884

Reaction notes

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