2-Chlorobenzoyl chloride → 5-(2-Chlorobenzamido)-4-(2-chlorobenzoyl)-3-methyl-1-(2,4,6-trichlorophenyl)pyrazole

Participants

Reaction Steps

A suspension of 2.34 g (17.50 mmol) of aluminum trichloride in 20 mL of 1,1,2,2-tetrachloroethane was treated with 2.02 mL (2.78 g, 15.9 mmol) of 2-chlorobenzoyl chloride and the resulting solution was stirred for 20 minutes at room temperature. Then 2.00 g (7.23 mmol) of the product of Step A was added and the reaction mixture was refluxed for 16 hours. The cooled reaction mixture was poured over ice and the insolubles were filtered off and washed with ethyl acetate. The organic layer was separated and the aqueous was washed twice with ethyl acetate. The combined organic layers were dried over magnesium sulfate and evaporated. The residues were chromatographed on silica gel, eluting with 4:1 hexane ethyl acetate to give 2.05 g (51%) of the title product, an amorphous foam.

Provenance & Evidence