Trimethylsilyldiazomethane → methyl 1H-indazole-4-carboxylate

HRID 2172954Notes

Reaction equation

HRID 2172954 reaction equation
[NH:1]1[C:9]2[CH:8]=[CH:7][CH:6]=[C:5]([C:10]([OH:12])=[O:11])[C:4]=2[CH:3]=[N:2]1.[CH3:13][Si](C=[N+]=[N-])(C)C>CO.C1(C)C=CC=CC=1>[CH3:13][O:11][C:10]([C:5]1[C:4]2[CH:3]=[N:2][NH:1][C:9]=2[CH:8]=[CH:7][CH:6]=1)=[O:12]

Participants

5

Reactant 2

HCID 167693TrimethylsilyldiazomethaneHCID 219823231H-indazole-4-carboxylic acid

Product 1

HCID 6623327methyl 1H-indazole-4-carboxylate

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 1140TolueneSolvent2×

Procedure

Indazole-4-carboxylic acid (2.00 g, 12.3 mmol) is suspended in methanol (20 mL) and toluene (30 mL) at room temperature. A solution of 2M trimethylsilyl diazomethane (12 mL, 24 mmol) in toluene is added slowly and the mixture is stirred at room temperature until the solution turned yellow. The reaction is quenched with concentrated acetic acid (5 mL) and the solvent is removed in vacuo. The residue is purified by silica gel chromatography eluting with a gradient of 0-30% ethyl acetate in hexanes to afford 1H-indazole-4-carboxylic acid methyl ester.

Workup

  1. customat room temperature
  2. customThe reaction is quenched with concentrated acetic acid (5 mL)
  3. customthe solvent is removed in vacuo
  4. customThe residue is purified by silica gel chromatography
  5. washeluting with a gradient of 0-30% ethyl acetate in hexanes

Sources & evidence

ORD record
ord-efcd8f5ef1d6441ea583842ef338f8dc
Source dataset
uspto-grants-2015_06
Patent number
US09056858B2

Reaction notes

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