4-Chlorobenzoyl chloride → 2-Chloro-1-[4-(4-chlorobenzoyl )-1-methyl-1H-pyrrol-2-yl]-ethanone

Participants

Reaction Steps

A solution of 30 g (0.19 mole) of 2-chloro-1-(1-methyl-1H-pyrrol-2-yl)-ethanone (10) in 180 mL 1,2-dichloroethane (DCE) under an argon atmosphere was cooled in an ice bath and 60 g AlCl3 (0.45 mole) was added in portions. After stirring for 10 minutes, a solution of 24 mL (0.19 mole) 4-chlorobenzoyl chloride in 110 mL DCE was added dropwise. The ice bath was removed and the reaction was stirred at room temperature overnight. The reaction was poured into 1N HCl/ice and the aqueous layer was extracted three times with methylene chloride. The organics solutions were combined, washed with water, 1N NaOH, water, brine, and dried (MgSO4). Evaporation of the solvent in vacuo gave a solid which was recrystallized from ethyl acetate/methylcyclohexane to give 27.67 g of a solid: mp 130°-132° C.; NMR 300 MHz (CDCl3) d 7.8 (m, 2H); 7.6-7.4 (m, 4H); 4.5 (s, 2H); 4.0 (s, 3H). Anal Calcd for C14H11Cl2NO2 : C, 56.78; H, 3.74; N, 4.73. Found: C, 56.72; H, 3.76; N, 4.73.

Provenance & Evidence