Iodoethane → Ethyl 4-ethyl-6-fluoro-3,4-dihydro-3-oxo-2-quinoxalinecarboxylate

HRID 1973379Notes

Reaction equation

HRID 1973379 reaction equation
[F:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[N:8]=[C:7]([C:12]([O:14][CH2:15][CH3:16])=[O:13])[C:6](=[O:17])[NH:5]2.F[C:19]1C=C2C(NC(=O)C(C(OCC)=O)=N2)=C[CH:20]=1.C(I)C.C(=O)([O-])[O-].[K+].[K+]>CC(=O)CC>[CH2:19]([N:5]1[C:4]2[C:9](=[CH:10][CH:11]=[C:2]([F:1])[CH:3]=2)[N:8]=[C:7]([C:12]([O:14][CH2:15][CH3:16])=[O:13])[C:6]1=[O:17])[CH3:20]

Participants

6

Reactant 4

HCID 6340IodoethaneHCID 11430Potassium CarbonateHCID 10752268HCID 10752268, compoundHCID 10823684HCID 10823684, compound

Product 1

HCID 86734255Ethyl 4-ethyl-6-fluoro-3,4-dihydro-3-oxo-2-quinoxalinecarboxylate

Reagents, catalysts & solvents 1

HCID 6569Methyl Ethyl KetoneSolvent

Procedure

The mixture of 6-fluoro-3,4-dihydro-3-oxo-2-quinoxalinecarboxylic acid, ethyl ester and 7-fluoro-3,4-dihydro-3-oxo-2-quinoxalinecarboxylic acid, ethyl ester (Example 22a) (2 g), ethyl iodide (4 g) and anhydrous potassium carbonate (5.9 g) in 2-butanone (200 ml) were heated under reflux for 5 hours. The mixture was filtered and the filtrate was evaporated. The residual oil was chromatographed on silica using a mixture of petroleum ether (b.p. 60°-80°) and ethyl acetate (3:1) as eluent to give the required product, on evaporation of the later fractions, m.p. 99°-101.5°, (50%).

Workup

  1. temperaturewere heated
  2. temperatureunder reflux for 5 hours
  3. filtrationThe mixture was filtered
  4. customthe filtrate was evaporated
  5. customThe residual oil was chromatographed on silica using
  6. additiona mixture of petroleum ether (b.p. 60°-80°) and ethyl acetate (3:1) as eluent

Sources & evidence

ORD record
ord-7dd95d4a2a0b42f9b8a0209babd1e711
Source dataset
uspto-grants-1976_12
Patent number
US03997535

Reaction notes

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