Reacción #6774

Ecuación de reacción

2,6-dichloro-3-aminotoluene

dimethyl acetylenedicarboxylate

→

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

Rendimiento 90.6%

Disolventes

methanol

Condiciones de reacción

Tratamiento posterior

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

Procedimiento

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.

Fuente