Reaction #1442519

Reaction equation

3-(4-chlorophenyl)furan-2,5-dione

thionyl chloride

pyridine

→

3-Chloro-4-(4-chlorophenyl)furan-2,5-dione

Conditions

Workup

1. 1
   TemperatureWith ice-cooling
2. 2
   Temperatureheated at 75° C. for 10 min
3. 3
   Temperatureto cool
4. 4
   Otherexcess thionyl chloride was removed at 60° C. under reduced pressure
5. 5
   Filtrationfiltered
6. 6
   Filtrationfiltered whilst still hot
7. 7
   ConcentrationThe filtrate was concentrated under reduced pressure
8. 8
   Temperaturecooled
9. 9
   Filtrationfiltered off
10. 10
    Washwashed once more with petroleum ether
11. 11
    Otherdried under reduced pressure

Procedure

With ice-cooling, 15.0 g (72 mmol) of 3-(4-chlorophenyl)furan-2,5-dione were added to 72 ml of thionyl chloride, and the mixture was admixed dropwise over a period 10 min with 11.5 g (145 mmol) of pyridine, the temperature being maintained at 10-12° C. The mixture was stirred at 10-12° C. for 30 min, heated at 75° C. for 10 min using a preheated heating bath and allowed to cool, and excess thionyl chloride was removed at 60° C. under reduced pressure. The residue was boiled with 200 ml of toluene and filtered, and the residue was again boiled with 100 ml of toluene and filtered whilst still hot. The filtrate was concentrated under reduced pressure and the residue was boiled with 100 ml of petroleum ether, cooled, filtered off, washed once more with petroleum ether and dried under reduced pressure. Yield: 16.2 g, m.p. 110-112° C.

Source