Iodoethane → Ethyl 4-ethoxy-1-ethyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylate

HRID 1576817Notes

Reaction equation

HRID 1576817 reaction equation
[CH2:1]([O:3][C:4]([C:6]1[C:7]([OH:17])=[C:8]2[CH:14]=[N:13][N:12]([CH2:15][CH3:16])[C:9]2=[N:10][CH:11]=1)=[O:5])[CH3:2].C(=O)([O-])[O-].[K+].[K+].[CH2:24](I)[CH3:25]>CN(C)C=O>[CH2:1]([O:3][C:4]([C:6]1[C:7]([O:17][CH2:24][CH3:25])=[C:8]2[CH:14]=[N:13][N:12]([CH2:15][CH3:16])[C:9]2=[N:10][CH:11]=1)=[O:5])[CH3:2]

Participants

5

Reactant 3

HCID 6340IodoethaneHCID 11430Potassium CarbonateHCID 178469631HCID 178469631, compound

Product 1

HCID 13072976Ethyl 4-ethoxy-1-ethyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylate

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

In a solution of 259 g. 1-ethyl-4-hydroxy-1H-pyrazolo[3,4-b]pyridine-5-carboxylic acid ethyl ester (1.1 mol.) in 1700 ml. dimethylformamide, 400 g. of well pulverized potassium carbonate and 300 g. of ethyl iodide are introduced. The reaction mixture is stirred for 7 hours at 65° and filtered under suction, while hot, to remove excess potassium carbonate. Upon standing over night, 165 g. of 4-ethoxy-1-ethyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylic acid ethyl ester crystallize out of the solution, m.p. 112°-115°. After evaporation of the mother liquor, an additional 80 g. are obtained. The total yield amounts to 85% of theory. The compound is recrystallized from ligroin (90°-100°), m.p. 113°-115°.

Workup

  1. filtrationfiltered under suction
  2. customwhile hot, to remove excess potassium carbonate
  3. waitUpon standing over night
  4. customof 4-ethoxy-1-ethyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylic acid ethyl ester crystallize out of the solution, m.p. 112°-115°
  5. customAfter evaporation of the mother liquor
  6. customare obtained
  7. customThe total yield
  8. customThe compound is recrystallized from ligroin (90°-100°), m.p. 113°-115°

Sources & evidence

ORD record
ord-3222698d642f450db90561b9692eb657
Source dataset
uspto-grants-1976_09
Patent number
US03983128

Reaction notes

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