Nitric Acid → 5-Fluoro-7-nitro-1,3-dihydro-indol-2-one

HRID 2191434Notes

Reaction equation

HRID 2191434 reaction equation
[F:1][C:2]1[CH:3]=[C:4]2[C:8](=[CH:9][CH:10]=1)[NH:7][C:6](=[O:11])[CH2:5]2.[N+:12]([O-:15])([OH:14])=[O:13]>S(=O)(=O)(O)O>[F:1][C:2]1[CH:10]=[C:9]([N+:12]([O-:14])=[O:13])[C:8]2[C:4](=[CH:5][C:6](=[O:11])[N:7]=2)[CH:3]=1.[F:1][C:2]1[CH:3]=[C:4]2[C:8](=[C:9]([N+:12]([O-:15])=[O:13])[CH:10]=1)[NH:7][C:6](=[O:11])[CH2:5]2

Participants

5

Reactant 2

HCID 944Nitric AcidHCID 37310125-fluoro-1,3-dihydro-2H-indol-2-one

Product 2

HCID 592500625-Fluoro-7-nitro-1,3-dihydro-indol-2-oneYield 62.5%HCID 685262775-Fluoro-7-nitro-indol-2-one

Reagents, catalysts & solvents 1

HCID 1118Sulfuric AcidSolvent

Conditions

Temperature
-5 °C

Procedure

5-Fluoro-1,3-dihydro-indol-2-one 4a (5.0 g, 33 mmol) was dissolved in sulfuric acid (17.6 ml, 98%) under stirring at −5° C., and nitric acid (2.1 ml, 65%-68%) was added to the solution while maintaining the temperature below 0° C. Upon completion of the addition, the mixture was stirred at room temperature for 1 hour. After thin lay chromatography showed the disappearance of starting materials, the reaction mixture was poured into ice water and filtered after ice-out. The filter cake was washed with water for three times, and the resulting solid was recrystallized to obtain the title compound 5-fluoro-7-nitro-1,3-dihydro-indol-2-one 20a (4.0 g, yield 62.5%) as an orange solid.

Workup

  1. temperaturewhile maintaining the temperature below 0° C
  2. additionUpon completion of the addition
  3. stirringthe mixture was stirred at room temperature for 1 hour
  4. filtrationfiltered after ice-out
  5. washThe filter cake was washed with water for three times
  6. customthe resulting solid was recrystallized

Sources & evidence

ORD record
ord-ffcaafb9acd74514a62fa620c69ab6d6
Source dataset
uspto-grants-2012_12
Patent number
US08329682B2

Reaction notes

Loading…