2-Aminopyridine → HCID 19610850, compound

HRID 1602211Notes

Reaction equation

HRID 1602211 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][N:3]=1.Cl[C:9]1[C:10](=[O:24])[C:11]2[C:16]([C:17](=[O:20])[C:18]=1Cl)=[C:15]([N+:21]([O-:23])=[O:22])[CH:14]=[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:24])[C:11]2[CH:12]=[CH:13][CH:14]=[C:15]([N+:21]([O-:23])=[O:22])[C:16]1=2

Participants

4

Reactant 2

HCID 104392-AminopyridineHCID 43814362,3-Dichloro-5-nitro-1,4-naphthoquinone

Product 1

HCID 19610850HCID 19610850, compoundYield 4.5%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

1.73 g (18 mmol, 1 eq) of 2-aminopyridine are added to a suspension of 5.00 g (18 mmol), 1 eq) of 2,3-dichloro-1,4-dihydro-1,4-dioxo-5-nitronaphthalene in 400 mL of ethanol. The mixture is brought to reflux for 5 h. After an orange precipitate appears, the reaction is allowed to cool to ambient temperature and the precipitate is filtered and purified on a flash column (support: silica 6-35 μm, h=45 cm, δ=16 cm; conditioning: heptane/ethyl acetate, 50/50; eluant: heptane/ethyl acetate, 50/50 to 70/30) to obtain 0.54 g of 6,11-dihydro-6,11-dioxo-7-nitronaphtho[2',3':4,5]imidazo[1,2-a]pyridine or 6,11-dihydro-6,11-dioxo-10-nitronaphtho[2',3':4,5]imidazo[1,2-a]pyridine, which after recrystallization in 1,2-dichlorobenzene produces 0.24 g of the expected product in the form of orange crystals.

Workup

  1. temperatureto reflux for 5 h
  2. filtrationthe precipitate is filtered
  3. custompurified on a flash column (support: silica 6-35 μm, h=45 cm, δ=16 cm; conditioning: heptane/ethyl acetate, 50/50; eluant: heptane/ethyl acetate, 50/50 to 70/30)

Sources & evidence

ORD record
ord-e4555df707764fbea9abffd386504ac1
Source dataset
uspto-grants-1999_11
Patent number
US05981544

Reaction notes

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