Carbon Dioxide → 3-Amino-1H-indazol-4-ol

HRID 484913Notes

Reaction equation

HRID 484913 reaction equation
[Mg].[NH2:2][C:3]1[C:11]2[C:6](=[CH:7][CH:8]=[CH:9][C:10]=2Cl)[NH:5][N:4]=1.C(Br)(C)C.O=O.C(=O)=[O:20].S(=O)(=O)(O)O>O.C(OCC)C>[NH2:2][C:3]1[C:11]2[C:6](=[CH:7][CH:8]=[CH:9][C:10]=2[OH:20])[NH:5][N:4]=1

Participants

9

Reactant 6

HCID 280Carbon DioxideHCID 977OxygenHCID 1118Sulfuric AcidHCID 63582-BromopropaneHCID 3134443-Amino-4-chloroindazoleHCID 5462224Magnesium

Product 1

HCID 1355831063-Amino-1H-indazol-4-olYield 42%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 3283Diethyl EtherSolvent2×

Procedure

To 20 ml of diethyl ether solution containing 600 mg of magnesium powder was added dropwise a mixed solution consisting of 1.68 g of 3-amino-4-chloroindazole prepared by the method as described in Beck. Gunkther et al., Justus Liebigs Ann. Chem., 716, 47(1968), 2.06 g of isopropyl bromide and 20 ml of diethyl ether. Into the solution were introduced dried oxygen gas and dried carbon dioxide gas for 10 hours so as to reflux the solution, and the solution was left to stand for 12 hours. The pH of the solution was adjusted to 4.0 by adding dropwise sulfuric acid to the solution at 0° C. The solution was added with 50 ml of water and filtered. To the aqueous layer of the filtrate was added an aqueous potassium carbonate solution to separate crystals. The crystals were obtained by filtration and dried to give 0.626 g of 3-amino-4-hydroxyindazole having the following analytical values in a yield of 42%.

Workup

  1. additionwas added dropwise a mixed solution
  2. customprepared by the method
  3. temperatureto reflux the solution
  4. waitthe solution was left
  5. filtrationfiltered
  6. additionTo the aqueous layer of the filtrate was added an aqueous potassium carbonate solution
  7. customto separate crystals
  8. customThe crystals were obtained by filtration
  9. customdried

Sources & evidence

ORD record
ord-546df044b020431c9bda4f6819bc250c
Source dataset
uspto-grants-1985_08
Patent number
US04533731

Reaction notes

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