Methylhydrazine → Ethyl 1,4,4-trimethyl-7-oxo-4,5,6,7-tetrahydro-1H-indazole-3-carboxylate

HRID 875095Notes

Reaction equation

HRID 875095 reaction equation
C[O:2][C:3]1[C:4](=O)[CH:5]([C:11](=O)[C:12]([O:14][CH2:15][CH3:16])=[O:13])[C:6]([CH3:10])([CH3:9])[CH2:7][CH:8]=1.[CH3:19][NH:20][NH2:21]>C(O)(=O)C.O>[CH3:19][N:20]1[C:4]2[C:3](=[O:2])[CH2:8][CH2:7][C:6]([CH3:10])([CH3:9])[C:5]=2[C:11]([C:12]([O:14][CH2:15][CH3:16])=[O:13])=[N:21]1

Participants

5

Reactant 2

HCID 6061MethylhydrazineHCID 57444091HCID 57444091, compound

Product 1

HCID 44235648Ethyl 1,4,4-trimethyl-7-oxo-4,5,6,7-tetrahydro-1H-indazole-3-carboxylateYield 47.7%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolvent2×HCID 962WaterSolvent

Procedure

A solution of ethyl (3-methoxy-6,6-dimethyl-2-oxocyclohex-3-en-1-yl)(oxo)acetate from the previous step (40.2 mmol theoretically) in acetic acid (65 mL) was treated dropwise with a solution of methyl hydrazine (2.14 mL, 40.2 mmol) in acetic acid (20 mL) and allowed to stand at room temperature overnight. The mixture was then diluted with water (800 mL) and extracted with ethyl acetate (500 mL×2). The organic extracts were washed with brine, dried on Na2SO4 and evaporated to dryness. The crude material was chromatographed on silica gel eluted with dichloromethane/ethyl acetate 100:5 to obtain the pure title compound (4.8 g, 47.7% yield).

Workup

  1. extractionextracted with ethyl acetate (500 mL×2)
  2. washThe organic extracts were washed with brine
  3. customdried on Na2SO4
  4. customevaporated to dryness
  5. customThe crude material was chromatographed on silica gel
  6. washeluted with dichloromethane/ethyl acetate 100:5

Sources & evidence

ORD record
ord-7d70f53f06774f309b5c00497e1d6955
Source dataset
uspto-grants-2015_03
Patent number
US08981089B2

Reaction notes

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