Sodium hydride → 3-hydroxy-2,2-dimethyl-6-nitro-2H-1-benzopyran-4-carboxamide

HRID 36083Notes

Reaction equation

HRID 36083 reaction equation
[CH3:1][C:2]1([CH3:16])[C:7](=[O:8])[CH2:6][C:5]2[CH:9]=[C:10]([N+:13]([O-:15])=[O:14])[CH:11]=[CH:12][C:4]=2[O:3]1.[H-].[Na+].[C:19](C1NC=CN=1)(C1NC=CN=1)=[O:20].[Cl-].[NH4+:32]>C(N(CC)CC)C.CN(C)C=O>[OH:8][C:7]1[C:2]([CH3:16])([CH3:1])[O:3][C:4]2[CH:12]=[CH:11][C:10]([N+:13]([O-:15])=[O:14])=[CH:9][C:5]=2[C:6]=1[C:19]([NH2:32])=[O:20]

Participants

7

Reactant 4

HCID 24758Sodium hydrideHCID 25517Ammonium ChlorideHCID 5250894Bis-(1H-imidazol-2-YL)-methanoneHCID 15234740HCID 15234740, compound

Product 1

HCID 547196793-hydroxy-2,2-dimethyl-6-nitro-2H-1-benzopyran-4-carboxamideYield 46.8%

Reagents, catalysts & solvents 2

HCID 6228DimethylformamideSolventHCID 8471TriethylamineSolvent

Procedure

To a mixture of 41.5 g of 3,4-dihydro-2,2-dimethyl-6-nitro-2H-1-benzopyran-3-one and 500 ml of dried N,N-dimethylformamide was slowly added 8.2 g of sodium hydride (60%) in a nitrogen stream while stirring under cooling with ice. After stirring for 50 minutes, 33.5 g of carbonyl diimidazole was added thereto and the mixture stirred for 1 hour. To the reaction mixture were added 11.2 g of ammonium chloride and 29 ml of triethylamine, followed by stirring at 5° C. for 12 hours and then at room temperature for 14 hours. Ice-water was added to the reaction mixture, and the mixture was washed with diethyl ether. The aqueous layer was made acidic with hydrochloric acid and extracted with a mixed solvent of ethyl acetate and diethyl ether. The organic layer was washed with water and dried. The solvent was removed by distillation, and the residue was purified by silica gel column chromatography (developing solution: CH2Cl2 :MeOH=99:1) to obtain 23.2 g of 3-hydroxy-2,2-dimethyl-6-nitro-2H-1-benzopyran-4-carboxamide represented by formula shown below.

Workup

  1. temperatureunder cooling with ice
  2. stirringAfter stirring for 50 minutes
  3. stirringthe mixture stirred for 1 hour
  4. stirringby stirring at 5° C. for 12 hours
  5. washthe mixture was washed with diethyl ether
  6. extractionextracted with a mixed solvent of ethyl acetate and diethyl ether
  7. washThe organic layer was washed with water
  8. customdried
  9. customThe solvent was removed by distillation
  10. customthe residue was purified by silica gel column chromatography (developing solution: CH2Cl2 :MeOH=99:1)

Sources & evidence

ORD record
ord-47ea209da8ea4a15bad6151b5ba008ff
Source dataset
uspto-grants-1995_05
Patent number
US05412117

Reaction notes

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