Reaktion #332327

Reaktionsgleichung

6-bromo-3-methyl-2-[3-(trifluoromethyl)phenyl]-4-quinolinecarboxylic acid

oxalyl chloride

Methanol

→

methyl 6-bromo-3-(methyl)-2-[3-(trifluoromethyl)phenyl]-4-quinolinecarboxylate

Ausbeute 152.6%

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwas warmed to room temperature overnight
2. 2
   SonstigeThe solvent was removed under reduced pressure
3. 3
   workup.ADDITIONThe residue was treated with water (200 mL) and saturated aqueous NaHCO3 (300 mL)
4. 4
   Extraktionextracted with methylene chloride (500 mL)
5. 5
   ExtraktionThe aqueous phase was extracted with methylene chloride (300 mL)
6. 6
   WaschenThe organic phase was washed with saturated aqueous NaHCO3 and brine
7. 7
   Sonstigedried
8. 8
   Filtrationfiltered
9. 9
   Einengenconcentrated
10. 10
    TemperaturThe mixture was heated to 75° C. until the solid
11. 11
    workup.DISSOLUTIONcompletely dissolved
12. 12
    TemperaturThe mixture was cooled
13. 13
    Filtrationthe resulting precipitate was collected by filtration
14. 14
    Sonstigedried
15. 15
    EinengenThe filtrate was concentrated
16. 16
    Sonstigethe recrystallization procedure
17. 17
    Sonstigeto give additional product

Vorschrift

A solution of 6-bromo-3-methyl-2-[3-(trifluoromethyl)phenyl]-4-quinolinecarboxylic acid (50 g, 122 mmol) in dichloromethane (700 mL) was cooled to 0° C., and DMF (1.416 mL, 18.28 mmol) was added. To the cooled solution, oxalyl chloride (16.01 mL, 183 mmol) was added dropwise (slowly) and the mixture was stirred at 0° C. for 1 h. Methanol was added and after 2 h the mixture was warmed to room temperature overnight. The solvent was removed under reduced pressure. The residue was treated with water (200 mL) and saturated aqueous NaHCO3 (300 mL) and extracted with methylene chloride (500 mL). The aqueous phase was extracted with methylene chloride (300 mL). The organic phase was washed with saturated aqueous NaHCO3 and brine, dried, filtered, and concentrated. The resulting solid was combined with material from a separate experiment (51 g) and the material was suspended in 400-500 mL of acetonitrile. The mixture was heated to 75° C. until the solid completely dissolved. The mixture was cooled, and the resulting precipitate was collected by filtration and dried. The filtrate was concentrated and the recrystallization procedure was repeated to give additional product. Both batches were combined to afford methyl 6-bromo-3-(methyl)-2-[3-(trifluoromethyl)phenyl]-4-quinolinecarboxylate (79 g, 73% overall yield). MS (m/z) 426.0 (M+H+).

Quelle