Propylene Oxide → Imidazo1,2-aquinoline-2-carboxylic acid, 8-bromo-5-chloro-, ethyl ester

HRID 1277974Notes

Reaction equation

HRID 1277974 reaction equation
[NH2:1][C:2]1[CH:11]=[C:10]([Cl:12])[C:9]2[C:4](=[CH:5][C:6]([Br:13])=[CH:7][CH:8]=2)[N:3]=1.Br[CH2:15][C:16](=O)[C:17]([O:19][CH2:20][CH3:21])=[O:18].C1OC1C>C(COC)OC>[Br:13][C:6]1[CH:5]=[C:4]2[C:9]([C:10]([Cl:12])=[CH:11][C:2]3[N:3]2[CH:15]=[C:16]([C:17]([O:19][CH2:20][CH3:21])=[O:18])[N:1]=3)=[CH:8][CH:7]=1

Participants

5

Reactant 3

HCID 6378Propylene OxideHCID 66144Ethyl bromopyruvate2×HCID 140674317-Bromo-4-chloro-2-quinolinamine

Product 1

HCID 12763986Imidazo1,2-aquinoline-2-carboxylic acid, 8-bromo-5-chloro-, ethyl ester

Reagents, catalysts & solvents 1

HCID 80711,2-DimethoxyethaneSolvent2×

Procedure

1 g of 2-amino-7-bromo-4-chloroquinoline was suspended in 10 ml of dimethoxyethane and then a solution of 1 g of ethyl bromopyruvate and 300 mg of propylene oxide in 10 ml of dimethoxyethane was added. The mixture was stirred at room temperature for 2 days and 300 mg of ethyl bromopyruvate were then added. Stirring was continued for a further day and the precipitated quaternary salt was filtered off, washed with ether and then was suspended in 20 ml of ethanol. The mixture was heated at reflux for 2 hours and the solvent was removed under vacuum. The residue was partitioned between CHCl3 /Na2CO3 solution and the organic solution was dried over MgSO4 and the solvent was removed to leave a cream solid. This was purified by chromatography over silica with 5% methanol in chloroform as eluent and the product was crystallized from chloroform/ether to obtain pale cream needles of ethyl 8-bromo-5-chloroimidazo-[1,2-a]-quinoline-2-carboxylate melting at 206° to 207° C.

Workup

  1. stirringStirring
  2. waitwas continued for a further day
  3. filtrationthe precipitated quaternary salt was filtered off
  4. washwashed with ether
  5. temperatureThe mixture was heated
  6. temperatureat reflux for 2 hours
  7. customthe solvent was removed under vacuum
  8. customThe residue was partitioned between CHCl3 /Na2CO3 solution
  9. dry with materialthe organic solution was dried over MgSO4
  10. customthe solvent was removed
  11. customto leave a cream solid
  12. customThis was purified by chromatography over silica with 5% methanol in chloroform as eluent
  13. customthe product was crystallized from chloroform/ether

Sources & evidence

ORD record
ord-92845cb97f374e8988b0e5b7372ae5f5
Source dataset
uspto-grants-1981_07
Patent number
US04279912

Reaction notes

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