1,3-Dibromo-5,5-dimethylhydantoin → Methyl 3-bromo-6-bromomethyl-2-methoxybenzoate

HRID 2177754Notes

Reaction equation

HRID 2177754 reaction equation
[Br:1][C:2]1[C:3]([O:13][CH3:14])=[C:4]([C:9]([CH3:12])=[CH:10][CH:11]=1)[C:5]([O:7][CH3:8])=[O:6].CC(N=NC(C#N)(C)C)(C#N)C.[Br:27]N1C(C)(C)C(=O)N(Br)C1=O.C(Br)C1C=CC=CC=1>ClCCCl.[W]>[Br:1][C:2]1[C:3]([O:13][CH3:14])=[C:4]([C:9]([CH2:12][Br:27])=[CH:10][CH:11]=1)[C:5]([O:7][CH3:8])=[O:6]

Participants

7

Reactant 4

HCID 64791,3-Dibromo-5,5-dimethylhydantoinHCID 6547AzobisisobutyronitrileHCID 7498Benzyl BromideHCID 66685292Methyl 3-bromo-2-methoxy-6-methylbenzoate2×

Product 1

HCID 66685947Methyl 3-bromo-6-bromomethyl-2-methoxybenzoateYield 68.9%

Reagents, catalysts & solvents 2

HCID 23964TungstenCatalystHCID 111,2-DichloroethaneSolvent

Procedure

A solution of methyl 3-bromo-2-methoxy-6-methylbenzoate (Intermediate 91, 20 g) in 1,2-dichloroethane (400 ml) was stirred and illuminated with a 500 W tungsten filament lamp and treated with a catalytic amount of AIBN. Solid 1,3-dibromo-5,5-dimethylhydantoin (20 g) was gradually added over 3 hours until NMR analysis indicated complete conversion to the desired benzyl bromide. After cooling, the mixture was evaporated to dryness and the residue was triturated with cyclohexane and filtered. The filtrate was evaporated to dryness and the residue was purified by chromatography on silica, eluting with a mixture of DCM and cyclohexane with a gradient of 1-25% to give methyl 3-bromo-6-bromomethyl-2-methoxybenzoate (16.3 g) as an orange solid.

Workup

  1. temperatureAfter cooling
  2. customthe mixture was evaporated to dryness
  3. customthe residue was triturated with cyclohexane
  4. filtrationfiltered
  5. customThe filtrate was evaporated to dryness
  6. customthe residue was purified by chromatography on silica
  7. washeluting with a mixture of DCM and cyclohexane with a gradient of 1-25%

Sources & evidence

ORD record
ord-9dfc8d0d3be941f9b76f14b176ce410a
Source dataset
uspto-grants-2015_06
Patent number
US09067905B2

Reaction notes

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