Reaktion #6774

Reaktionsgleichung

2,6-dichloro-3-aminotoluene

dimethyl acetylenedicarboxylate

→

2-(methoxycarbonyl)-4-oxo-6,8-dichloro-7-methylquinoline

Ausbeute 90.6%

Lösungsmittel

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe reaction mixture was refluxed for 2 hours
2. 2
   EinengenThe reaction mixture was concentrated under reduced pressure to a yellow solid
3. 3
   TemperaturDiphenyl ether (350 mL) was heated to 230–240° C.
4. 4
   workup.ADDITIONthe yellow solid was added to it
5. 5
   TemperaturThe temperature was maintained at 230–240° C. for 20 minutes
6. 6
   workup.ADDITIONdiluted with petroleum ether (1L)
7. 7
   FiltrationThe solid was filtered
8. 8
   Waschenwashed with hot ethyl acetate

Vorschrift

To a solution of 2,6-dichloro-3-aminotoluene (20.5 g, 0.11 mol) in methanol (300 mL) was added dimethyl acetylenedicarboxylate (15 mL, 0.12 mol) and the reaction mixture was refluxed for 2 hours. The reaction mixture was concentrated under reduced pressure to a yellow solid. Diphenyl ether (350 mL) was heated to 230–240° C., and the yellow solid was added to it. The temperature was maintained at 230–240° C. for 20 minutes and the reaction mixture was cooled slowly to ambient temperature and diluted with petroleum ether (1L). The solid was filtered and washed with hot ethyl acetate to afford a brown solid, 2-(methoxycarbonyl)-4-oxo-6,8-dichloro-7-methylquinoline (28.5 g, 85%); NMR (CDCl3) 2.62 (s, 3), 4.04 (s, 3), 7.02 (s, 1), 8.24 (s, 1) ppm.

Quelle