Ethanol → N-Acetyl-4-(2,3-dichlorophenyl)-3-trifluoromethylpyrrole

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Reaction Conditions

Reaction Steps

2.7 g of glycine and 2.0 g of potassium hydroxide are dissolved in 160 ml of ethanol, and the mixture is heated to 45° C. There are then added at this temperature 9.9 g of the α-trifluoroacetyl-β-methoxy-2,3-dichlorostyrene produced according to Example P2, and the reaction mixture is refluxed for 90 minutes. The mixture is subsequently concentrated in vacuo; to the residue are afterwards added 150 ml of acetic anhydride, and the new mixture is heated at 100° C. for 45 minutes. After the evolution of CO2 has subsided, the solvent is removed by evaporation, and the residue is taken up in toluene, and filtered through SiO2. The filtrate is again concentrated by evaporation, and the oily residue is covered with hexane, in the course of which N-acetyl-4-(2,3-dichlorophenyl)-3-trifluoromethylpyrrole precipitates in the form of beige crystals, m.p. 65°-66° C.

Provenance & Evidence