Water → 1-ethyl-4-chloro-7-carboxy-1H-pyrazolo[3,4-b]quinoline

HRID 1586160Notes

Reaction equation

HRID 1586160 reaction equation
[CH2:1]([N:3]1[C:7]([NH:8][C:9]2[C:10](=[CH:14][CH:15]=[C:16]([C:18]([OH:20])=[O:19])[CH:17]=2)[C:11](O)=O)=[CH:6][CH:5]=[N:4]1)[CH3:2].O=P(Cl)(Cl)[Cl:23].O>C(O)(=O)C>[CH2:1]([N:3]1[C:7]2=[N:8][C:9]3[C:10]([C:11]([Cl:23])=[C:6]2[CH:5]=[N:4]1)=[CH:14][CH:15]=[C:16]([C:18]([OH:20])=[O:19])[CH:17]=3)[CH3:2]

Participants

5

Reactant 3

HCID 962WaterHCID 24813Phosphorus oxychlorideHCID 21217714N-(1-ethylpyrazol-5-yl)-4-carboxyanthranilic acid

Product 1

HCID 212177041-ethyl-4-chloro-7-carboxy-1H-pyrazolo[3,4-b]quinoline

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

A mixture of N-(1-ethylpyrazol-5-yl)-4-carboxyanthranilic acid (2.5 g) and POCl3 (20 ml) is refluxed overnight. The reaction mixture is poured into water, acidified with acetic acid, and the solids which form are collected by filtration. The solid is taken up in 10% NaOH, washed with ether and then the aqueous layer is acidified with concentrated HCl. The mixture is extracted with ether, the ether layer is dried over MgSO4 filtered and evaporated to afford 1 g of 1-ethyl-4-chloro-7-carboxy-1H-pyrazolo[3,4-b]quinoline, as a yellow powder.

Workup

  1. temperatureis refluxed overnight
  2. filtrationthe solids which form are collected by filtration
  3. washwashed with ether
  4. extractionThe mixture is extracted with ether
  5. dry with materialthe ether layer is dried over MgSO4
  6. filtrationfiltered
  7. customevaporated

Sources & evidence

ORD record
ord-a5e3ed1e265449028f28dc3804e27863
Source dataset
uspto-grants-1999_08
Patent number
US05942520

Reaction notes

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