Benzoyl Peroxide → 4-Bromo-7-hydroxy-2-phenyl-oxazolo[4,5-c]pyridine-6-carboxylic acid methyl ester

HRID 2388137Notes

Reaction equation

HRID 2388137 reaction equation
[CH3:1][O:2][C:3]([C:5]1[N:10]=[CH:9][C:8]2[N:11]=[C:12]([C:14]3[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=3)[O:13][C:7]=2[C:6]=1[OH:20])=[O:4].[Br:21]N1C(=O)CCC1=O.C(OOC(=O)C1C=CC=CC=1)(=O)C1C=CC=CC=1>C1C=CC=CC=1>[CH3:1][O:2][C:3]([C:5]1[N:10]=[C:9]([Br:21])[C:8]2[N:11]=[C:12]([C:14]3[CH:15]=[CH:16][CH:17]=[CH:18][CH:19]=3)[O:13][C:7]=2[C:6]=1[OH:20])=[O:4]

Participants

5

Reactant 3

HCID 7187Benzoyl PeroxideHCID 67184N-bromobutanimideHCID 675295697-Hydroxy-2-phenyl-oxazolo[4,5-c]pyridine-6-carboxylic acid methyl ester

Product 1

HCID 866481114-Bromo-7-hydroxy-2-phenyl-oxazolo[4,5-c]pyridine-6-carboxylic acid methyl esterYield 61%

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent

Procedure

A suspension of 7-hydroxy-2-phenyl-oxazolo[4,5-c]pyridine-6-carboxylic acid methyl ester (3.57 g, 13.2 mmol; example 1d), N-bromosuccinimide (2.47 g, 13.9 mmol), and benzoyl peroxide (320 mg, 1.32 mmol) in 43 mL of benzene was heated at reflux temperature for 5 hours. The reaction mixture was washed successively with saturated sodium bicarbonate, brine, saturated ammonium chloride solution, and brine. The organic solution was dried, filtered, and concentrated. The residue was purified by flash chromatography eluting from silica gel with a gradient of 0-25% methanol in methylene chloride to give 2.81 g of the title compound as a light yellow solid. MS: (+) m/z 348.9, 350.9 (M+1, 79Br/81Br).

Workup

  1. temperaturewas heated
  2. temperatureat reflux temperature for 5 hours
  3. washThe reaction mixture was washed successively with saturated sodium bicarbonate, brine, saturated ammonium chloride solution, and brine
  4. customThe organic solution was dried
  5. filtrationfiltered
  6. concentrationconcentrated
  7. customThe residue was purified by flash chromatography
  8. washeluting from silica gel with a gradient of 0-25% methanol in methylene chloride

Sources & evidence

ORD record
ord-2861dd26dd344c899dda14ad950df6e6
Source dataset
uspto-grants-2012_09
Patent number
US08269008B2

Reaction notes

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