1,3-Dibromo-5,5-dimethylhydantoin → 2-Bromo-5-methoxybenzyl bromide

HRID 1006053Notes

Reaction equation

N(C(C)(C)C#N)=NC(C)(C)C#N.[Br:13][C:14]1[CH:19]=[CH:18][C:17]([O:20][CH3:21])=[CH:16][C:15]=1[CH3:22].CC1(C)N([Br:29])C(=O)N(Br)C1=O.S([O-])([O-])(=O)=S.[Na+].[Na+]>ClC1C=CC=CC=1>[Br:13][C:14]1[CH:19]=[CH:18][C:17]([O:20][CH3:21])=[CH:16][C:15]=1[CH2:22][Br:29]

Participants

Conditions

Temperature: 70 °C

Procedure

Azobisisobutyronitrile (0.60 g) was added to a mixture of 2-bromo-5-methoxytoluene (77.38 g, 384 mmol), 5,5-dimethy-1,3-dibromohydantoin (57.5 g, 200 mmol) and chlorobenzene (1500 mL), followed by stirring at 70° C. for 2 hours. Azobisisobutyronitrile (0.60 g) was added thereto again and stirred for another 1 hour. A 10% aqueous sodium thiosulfate solution (500 mL) was added to the reaction mixture, and the resulting mixture was washed with a saturated aqueous sodium chloride solution. The mixture washed was dried over anhydrous magnesium sulfate and then concentrated to dryness to obtain a crude product of 2-bromo-5-methoxybenzyl bromide. Thereto was added 100 mL of ice-cooled hexane to obtain a homogeneous slurry, which was filtered. The residue was washed with 100 mL of ice-cooled hexane and then dried under reduced pressure to obtain 65.75 g (235 mmol, 61.1%) of 2-bromo-5-methoxybenzyl bromide.

Workup

stirringagain and stirred for another 1 hour
washthe resulting mixture was washed with a saturated aqueous sodium chloride solution
washThe mixture washed
dry with materialwas dried over anhydrous magnesium sulfate
concentrationconcentrated to dryness

Sources & evidence

ORD record: ord-a23d7b4c65964adf9739fa92310232e5
Source dataset: uspto-grants-2004_09
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US06787560B2

Reaction notes

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