2-Aminopyridine → HCID 19610851, compound

HRID 1602212Notes

Reaction equation

HRID 1602212 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][N:3]=1.Br[C:9]1[C:10](=[O:22])[C:11]2[C:16]([C:17](=[O:20])[C:18]=1Br)=[CH:15][C:14]([F:21])=[CH:13][CH:12]=2>C(O)C>[O:20]=[C:17]1[C:18]2[N:1]=[C:2]3[CH:7]=[CH:6][CH:5]=[CH:4][N:3]3[C:9]=2[C:10](=[O:22])[C:11]2[CH:12]=[CH:13][C:14]([F:21])=[CH:15][C:16]1=2

Participants

4

Reactant 2

HCID 104392-AminopyridineHCID 21184406HCID 21184406, compound

Product 1

HCID 19610851HCID 19610851, compoundYield 42%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

1.4 g (15 mmol, 2 eq) of 2-aminopyridine are added to a suspension of 2.5 g (7.5 mmol, 1.0 eq) of 2,3-dibromo-1,4-dihydro-1,4-dioxo-6-fluoronaphthalene in 50 mL of ethanol. The reaction mixture is brought to reflux of the solvent for 20 h, then brought to ambient temperature. The tan precipitate formed is filtered and washed profusely with ethanol. The solid obtained is purified by flash chromatography on a column of silica gel (support: silica 6-35 mm; (10 cm φ, 25 cm h; eluant: dichloromethane/ethyl acetate, 70/30). 494 mg of 6,11-dihydro-6,11-dioxo-8-fluoronaphtho[2',3':4,5]imidazo[1,2-a]pyridine or 6,11-dihydro-6,11-dioxo-9-fluoronaphtho[2',3':4,5]imidazo-[1,2-a] pyridine or 5,6-dihydro-5,6-dioxo-3-fluoronaphtho[1',2':4,5] imidazo[1,2-a]pyridine are obtained in the form of yellow crystals.

Workup

  1. temperatureto reflux of the solvent for 20 h
  2. custombrought to ambient temperature
  3. customThe tan precipitate formed
  4. filtrationis filtered
  5. washwashed profusely with ethanol
  6. customThe solid obtained
  7. customis purified by flash chromatography on a column of silica gel (support

Sources & evidence

ORD record
ord-622890355f1d4b5cbbe11754d373588b
Source dataset
uspto-grants-1999_11
Patent number
US05981544

Reaction notes

Loading…