p-Toluenesulfonic acid monohydrate → 7-Bromo-2-tert-butyl-6-iodo-5-methyl-1,3-benzoxazole-4-carbonitrile

HRID 17266

Reaction equation

HRID 17266 reaction equation
O.C1(C)C=CC(S(O)(=O)=O)=CC=1.[Br:13][C:14]1[C:15]([OH:31])=[C:16]([NH:24][C:25](=O)[C:26]([CH3:29])([CH3:28])[CH3:27])[C:17]([C:22]#[N:23])=[C:18]([CH3:21])[C:19]=1[I:20].O.C(=O)(O)[O-].[Na+]>C1(C)C=CC=CC=1>[Br:13][C:14]1[C:19]([I:20])=[C:18]([CH3:21])[C:17]([C:22]#[N:23])=[C:16]2[C:15]=1[O:31][C:25]([C:26]([CH3:27])([CH3:28])[CH3:29])=[N:24]2

Participants

5

Reactant 3

HCID 521998p-Toluenesulfonic acid monohydrateHCID 86585896Sodium bicarbonate waterHCID 86630797N-(3-bromo-6-cyano-2-hydroxy-4-iodo-5-methylphenyl)-2,2-dimethylpropionamide

Product 1

HCID 685859347-Bromo-2-tert-butyl-6-iodo-5-methyl-1,3-benzoxazole-4-carbonitrileYield 94%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

Toluene (25 ml), p-toluenesulfonic acid monohydrate (10.9 mg, 57.2 μmol) were added to N-(3-bromo-6-cyano-2-hydroxy-4-iodo-5-methylphenyl)-2,2-dimethylpropionamide (I-7) (250 mg, 572 μmol), followed by refluxing with a Dean-Stark condenser for 3 hours. After cooling, saturated sodium bicarbonate water (30 ml) was added to the reaction liquid, the product was extracted with ethyl acetate (50 ml×2). The organic layer was washed with saturated brine (50 ml), dried over anhydrous magnesium sulfate, concentrated under reduced pressure, the residue was purified by silica gel column chromatography (n-hexane:ethyl acetate=6:1) to obtain the entitled compound (225 mg, 94%) as a pale yellow solid.

Workup

  1. temperatureby refluxing with a Dean-Stark condenser for 3 hours
  2. temperatureAfter cooling
  3. extractionthe product was extracted with ethyl acetate (50 ml×2)
  4. washThe organic layer was washed with saturated brine (50 ml)
  5. dry with materialdried over anhydrous magnesium sulfate
  6. concentrationconcentrated under reduced pressure
  7. customthe residue was purified by silica gel column chromatography (n-hexane:ethyl acetate=6:1)

Sources & evidence

ORD record
ord-d082ca65db004cb3a7b902cc333cd858
Source dataset
uspto-grants-2010_06
Patent number
US07737166B2

Linked notes

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