Potassium Carbonate → methyl 6-amino-5-methyl-2H-indazole-7-carboxylate

HRID 245614Notes

Reaction equation

HRID 245614 reaction equation
[CH3:1][O:2][C:3]([C:5]1[C:6]([NH2:15])=[C:7](Br)[CH:8]=[C:9]2[C:13]=1[NH:12][N:11]=[CH:10]2)=[O:4].[C:16]([O-])([O-])=O.[K+].[K+].CB1OB(C)OB(C)O1>O1CCOCC1>[CH3:1][O:2][C:3]([C:5]1[C:6]([NH2:15])=[C:7]([CH3:16])[CH:8]=[C:9]2[C:13]=1[NH:12][N:11]=[CH:10]2)=[O:4]

Participants

5

Reactant 3

HCID 11430Potassium CarbonateHCID 574072TrimethylboroxineHCID 57990193HCID 57990193, compound

Product 1

HCID 57990198methyl 6-amino-5-methyl-2H-indazole-7-carboxylateYield 43%

Reagents, catalysts & solvents 1

HCID 312751,4-DioxaneSolvent

Conditions

Temperature
180 °C

Procedure

To a solution of 500 mg (1.85 mmol) of 6-amino-5-bromo-1H-indazole-7-carboxylic acid methyl ester, prepared as in step a in example 16, in 10 mL of dioxane under an atmosphere of argon is added 767 mg (5.55 mmol) of K2CO3, 106 mg (0.09 mmol) of tetrakis(triphenylphsophine)palladium and 232 mg (1.85 mmol) of trimethylboroxine. The reaction mixture is stirred in a microwave oven at 180° C. for 5 minutes. After filtration over Celite and concentration in vacuo, the residue is purified sequentially by flash chromatography (SiO2, hexanes/ethyl acetate 6:4) and reverse phase chromatography to afford 163 mg of product (43% over two steps) as a pale yellowish solid; LC/MS:206/207 (M+H)+.

Workup

  1. filtrationAfter filtration
  2. concentrationover Celite and concentration in vacuo
  3. customthe residue is purified sequentially by flash chromatography (SiO2, hexanes/ethyl acetate 6:4)

Sources & evidence

ORD record
ord-cd934c002a61467d8c2b57b6afe546f2
Source dataset
uspto-grants-2014_02
Patent number
US08658801B2

Reaction notes

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