Ethyl 4-methyl-3-nitrobenzoate → Ethyl 1H-indazole-6-carboxylate

HRID 258261Notes

Reaction equation

HRID 258261 reaction equation
[CH3:1][C:2]1[CH:12]=[CH:11][C:5]([C:6]([O:8][CH2:9][CH3:10])=[O:7])=[CH:4][C:3]=1[N+:13]([O-])=O.[N:16]([O-])=O.[Na+]>C(O)(=O)C.O>[NH:13]1[C:3]2[C:2](=[CH:12][CH:11]=[C:5]([C:6]([O:8][CH2:9][CH3:10])=[O:7])[CH:4]=2)[CH:1]=[N:16]1

Participants

5

Reactant 2

HCID 14945864Ethyl 4-methyl-3-nitrobenzoateHCID 23668193Sodium Nitrite

Product 1

HCID 19737203Ethyl 1H-indazole-6-carboxylateYield 102%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 962WaterSolvent

Procedure

Ethyl 4-methyl-3-nitrobenzoate (105 g) was dissolved in glacial acetic acid (4 1), followed by stirring. To the solution, a solution of sodium nitrite (32 g) in water (80 ml) was added at once at a temperature of 10° C. to 15° C., and the resultant mixture was stirred at room temperature for 3 days. After completion of the reaction, the reaction mixture was evaporated under reduced pressure to remove acetic acid. Water was added to the residue, and the precipitated crystals were collected by filtration. The collected crystals were washed with water and dried. The obtained crystals was further washed with methanol and diethyl ether, and dried to give ethyl indazol-6-yl carboxylate (90 g), m.p. 125°-126° C.

Workup

  1. customAfter completion of the reaction
  2. customthe reaction mixture was evaporated under reduced pressure
  3. customto remove acetic acid
  4. additionWater was added to the residue
  5. filtrationthe precipitated crystals were collected by filtration
  6. washThe collected crystals were washed with water
  7. customdried
  8. washThe obtained crystals was further washed with methanol and diethyl ether
  9. customdried

Sources & evidence

ORD record
ord-4e1966ecea50402686aeb40aa4016c67
Source dataset
uspto-grants-1993_11
Patent number
US05266556

Reaction notes

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