Hydrochloric Acid → 6-amino-5-methyl-2H-indazole-7-carboxylic acid

HRID 1907134Notes

Reaction equation

HRID 1907134 reaction equation
[CH3:1][C:2]1[CH:3]=[C:4]2[C:8](=[C:9]3[C:13](=[O:14])C(=O)[NH:11][C:10]=13)[NH:7][N:6]=[CH:5]2.[OH:16]O.Cl>[OH-].[Na+]>[NH2:11][C:10]1[C:9]([C:13]([OH:14])=[O:16])=[C:8]2[C:4]([CH:5]=[N:6][NH:7]2)=[CH:3][C:2]=1[CH3:1]

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 784Hydrogen PeroxideHCID 1358740205-methyl-1H,6H,7H,8H-pyrrolo[2,3-g]indazole-7,8-dione

Product 1

HCID 468557186-amino-5-methyl-2H-indazole-7-carboxylic acid

Reagents, catalysts & solvents 1

HCID 14798Sodium HydroxideSolvent

Procedure

To a solution of 5-methyl-1,6-dihydro-pyrrolo[2,3-g]indazole-7,8-dione (23 g, 114.3 mmol) in 4N aqueous sodium hydroxide solution (160 ml) at ambient temperature, was added dropwise 30% aqueous hydrogen peroxide solution (27 ml) maintaining the temperature <30° C. with external cooling. The resulting reaction mixture was stirred at ambient temperature for 2 hours. According to TLC, the reaction was complete after 2 hours. The pH was adjusted to pH 3.5 by addition of concentrated hydrochloric acid. The resulting brown suspension was filtered and the filtercake washed with cold water and dried in vacuo at 50° C. to afford the desired product as brown solid. LC/MS: 192 (M+H)+.

Workup

  1. temperaturemaintaining the temperature <30° C. with external cooling
  2. customThe resulting reaction mixture
  3. waitthe reaction was complete after 2 hours
  4. filtrationThe resulting brown suspension was filtered
  5. washthe filtercake washed with cold water
  6. customdried in vacuo at 50° C.

Sources & evidence

ORD record
ord-a3cf34dbe8094bce807e18fb46fbdc02
Source dataset
uspto-grants-2013_12
Patent number
US08598078B2

Reaction notes

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