One-Pot Synthesis of Trifluoromethylated Pyrazol-4-yl-pyrrole-2,5-dione Derivatives

Abstract

Efficient and convenient one-pot, three-component reactions of pyrrolidone, aromatic aldehydes and 1-phenyl-3-trifluoromethyl-5-pyrazolone afforded highly functionalized trifluoromethylated pyrazol-4-ylpyrrole-2,5-dione derivatives in good yields. The effect of solvents on the reaction efficiency and yield was briefly investigated. The structures of products were determined by spectral methods and X-ray diffraction analysis. The latter showed that the products formed have a strong intramolecular hydrogen bond, which made them particularly stable and the corresponding annulated products were not obtained by treatment with dehydrating reagents.