Asymmetric Tandem Michael Addition/Oxidation of Pyrazolones with p-Benzoquinone Using Cinchona Alkaloid Catalysts

Wang et al. have reported the cinchona alkaloid catalysts-promoted asymmetric tandem Michael addition/oxidation of pyrazolones with p-benzoquinone. According to their results, a cinchona alkaloid catalyst of quinine is effective for the reaction to proceed and a wide range of 4,4-disubstituted pyrazol-5-ones are formed with high yields and enantioselectivities. Since pyrazolones are an important class of structural motifs found in a diverse range of biologically active compounds such as antibacterials, this synthetic approach is expected to be applied in the field of drug development.