Nitric Acid → 7-Chloro-3-nitroindole-2-carboxylic acid

HRID 379911Notes

Reaction equation

HRID 379911 reaction equation
[N+:1]([O-:4])(O)=[O:2].C(OC(=O)C)(=O)C.[Cl:12][C:13]1[CH:14]=[CH:15][CH:16]=[C:17]2[C:21]=1[NH:20][C:19]([C:22]([OH:24])=[O:23])=[CH:18]2>>[Cl:12][C:13]1[CH:14]=[CH:15][CH:16]=[C:17]2[C:21]=1[NH:20][C:19]([C:22]([OH:24])=[O:23])=[C:18]2[N+:1]([O-:4])=[O:2]

Participants

4

Reactant 3

HCID 944Nitric AcidHCID 7918Acetic AnhydrideHCID 1200877-Chloro-1H-indole-2-carboxylic acid

Product 1

HCID 183678907-Chloro-3-nitroindole-2-carboxylic acid

Procedure

Seventy percent nitric acid (3.4 ml) was added to dropwise to acetic anhydride (35 ml) with stirring at room temperature. The mixture was then cooled in an ice bath and 7-chloroindole-2-carboxylic acid (EP 0 622 356 A1, 1.71 g, 8.74 mmol) was added carefully. After stirring for an additional 1.5 h, the suspension was filtered and the filter cake washed with hexane and air-dried. The yield of 7-chloro-3-nitroindole-2-carboxylic acid , yellow solids, was 283 mg (14%). 1H-NMR (DMSO-d6) δ: 13.66 (1H, br s), 8.04 (1H, dd, J=1.1, 8.1 Hz), 7.53 (1H, dd, J=1.1, 7.7 Hz), 7.42 (1H, dd, J=7.7, 8.1 Hz).

Workup

  1. temperatureThe mixture was then cooled in an ice bath
  2. stirringAfter stirring for an additional 1.5 h
  3. filtrationthe suspension was filtered
  4. washthe filter cake washed with hexane
  5. customair-dried

Sources & evidence

ORD record
ord-00edd50cc26d4722b3cb939559d01a14
Source dataset
uspto-grants-2001_10
Patent number
US06300363B1

Reaction notes

Loading…