Reaktion #607455

Reaktionsgleichung

HCl

2-Furoyl chloride

3,4-diaminoquinoline

dichloromethane

Water

→

2-Furyl-1H-Imidazo[4,5-c]quinoline

Lösungsmittel

pyridine

NaOH

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeto quench
2. 2
   Sonstigethe reaction
3. 3
   Sonstigethe solvent was evaporated under reduced pressure
4. 4
   Sonstigeto afford an orange solid
5. 5
   TemperaturAfter cooling on ice the pH
6. 6
   SonstigeThe solid that precipitated
7. 7
   Filtrationwas filtered off
8. 8
   Waschenwashed with water and ether
9. 9
   ExtraktionThen extracted with ethyl acetate (3 times 15 ml)
10. 10
    Waschenwashed with water (3 time 15 ml)
11. 11
    Trocknendried over MgSO4
12. 12
    SonstigeThe solvent was evaporated
13. 13
    Sonstigethe residue was dried

Vorschrift

2-Furoyl chloride (1.1 g, 0.8 ml, 8.1 mmol) in dry dichloromethane (15 ml) was added dropwise to a solution of to 3,4-diaminoquinoline 8 (1.0 g, 6.0 mmol) in dry pyridine (6.2 ml) under nitrogen. The solution was stirred for 2 hours at room temperature. Water (15 ml) was added to quench the reaction and the solvent was evaporated under reduced pressure to afford an orange solid. This crude solid in 2N NaOH (15 ml) was refluxed for 2 hours. After cooling on ice the pH was adjusted to 7 using concentrated HCl. The solid that precipitated was filtered off and washed with water and ether. Then extracted with ethyl acetate (3 times 15 ml) and washed with water (3 time 15 ml) and dried over MgSO4. The solvent was evaporated and the residue was dried. Eluent for column chromatography was 1-5% methanol in dichloromethane. Yield: 0.62 g (44%). Mp.: 236-238° C. 1H NMR (DMSO-d6): δ 6.74 (s, 1H, Ar); 7.35 (d, 1H, J=3.7 Hz, Ar); 7.69-7.73 (m, 2H, Ar); 7.83 (s, 1H, Ar); 8.09 (s, 1H, Ar); 8.46 (s, 1H, Ar); 9.09 (s, 1H, Ar). 13C NMR (DMSO-d6): δ 111.4, 112.6, 120.7, 121.8, 126.5, 127.2, 129.5, 138.2, 143.6, 144.3, 145.1, 147.2, 155.4.

Quelle