Butyryl chloride → Propionyl chloride

Participants

Reaction Steps

46.9 g (0.44 tool) of butyryl chloride are added dropwise to a suspension of 93.3 g (0.7 tool) of AlCl3 in 100 ml of methylene chloride in the course of 30 minutes, while stirring and cooling to -10° to -5°. A solution of 22.3 g (0.1 tool) of N-butylcarbazole in 50 ml of CH2Cl2 is then added dropwise at -10° to -5° in the course of 2 hours. The suspension is stirred at 0° to 20° for 16 hours and then poured onto ice. The emulsion formed is extracted twice with CHCl3 and the extract is washed with water, dried over MgSO4 and evaporated. The crude 3,6-dibutyryl-9-butyl-9H-carbazole is re-crystallized from 80 ml of ethanol. The resulting crystals have a melting point of 107°-109°. 3,6-Dipropionyl-9-butyl-9H-carbazole, which has a melting point of 142°-144° is obtained in an analogous manner from 81.4 g of propionyl chloride and 44.7 g of N-butylcarbazole.

Provenance & Evidence