Nitric Acid → 5-Nitro-2-oxindole

HRID 1386287Notes

Reaction equation

HRID 1386287 reaction equation
[N+:1]([O-:4])(O)=[O:2].[NH:5]1[C:13]2[C:8](=[CH:9][CH:10]=[CH:11][CH:12]=2)[CH2:7][C:6]1=[O:14].O>S(=O)(=O)(O)O>[N+:1]([C:10]1[CH:9]=[C:8]2[C:13](=[CH:12][CH:11]=1)[NH:5][C:6](=[O:14])[CH2:7]2)([O-:4])=[O:2]

Participants

5

Reactant 3

HCID 944Nitric AcidHCID 962WaterHCID 321710Oxindole

Product 1

HCID 2303665-Nitro-2-oxindoleYield 48%

Reagents, catalysts & solvents 1

HCID 1118Sulfuric AcidSolvent

Conditions

Temperature
0 °C

Procedure

Fuming nitric acid (1.58 ml, 39.4 mmol) was added dropwise to a solution of oxindole (5 g, 37.5 mmol) in concentrated sulphuric acid (25 ml) cooled by an ice bath and maintained below 5° C. The mixture was stirred for 30 minutes at 0° C. and then poured into water. The precipitate was collected by filtration and thoroughly washed with water. The solid was suspended in 50% acetic acid (100 ml) and heated at 90° C. for 1 hour. The mixture was allowed to cool, the solid product was collected by filtration, washed with water and dried under vacuum over phosphorus pentoxide at 40° C. to give 5-nitrooxindole (3.2 g, 48%).

Workup

  1. temperaturecooled by an ice bath
  2. temperaturemaintained below 5° C
  3. filtrationThe precipitate was collected by filtration
  4. washthoroughly washed with water
  5. temperatureheated at 90° C. for 1 hour
  6. temperatureto cool
  7. filtrationthe solid product was collected by filtration
  8. washwashed with water
  9. dry with materialdried under vacuum over phosphorus pentoxide at 40° C.

Sources & evidence

ORD record
ord-6c60100a11b74fa4a7f46abe942fe93c
Source dataset
uspto-grants-2001_07
Patent number
US06265411B1

Reaction notes

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