Addition reaction of pyrazolone with high regioselectivity and stereoselectivity by Lanzhou Chemical Institute

In the field of synthesis of chiral compounds and drug molecules, the development of new strategies to achieve high regioselectivity and stereoselectivity can provide an efficient way for the synthesis of various chiral molecules In recent decades, although the research of chiral catalysis has made great progress, it is still very difficult to use the same substrate to achieve high regioselectivity and stereoselectivity through the regulation of catalysts, especially in this process to achieve effective control of chiral quaternary carbon centers at the same time Pyrazolone compounds are five membered heterocyclic compounds with two adjacent nitrogen atoms As active structural units, pyrazolone compounds are widely used in drug molecules and natural products Recently, based on the understanding of reaction mechanism and electronic structure of substrate, Jiang Gaoxi, National Key Laboratory of carbonyl synthesis and selective oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences / Suzhou Research Institute, designed and realized the addition reaction of pyrazolone with high regionally high stereoselectivity diene Ether Catalyzed by transition metal palladium and organic small molecule phosphonic acid respectively In the palladium catalyst system, the branched chain addition products with two adjacent chiral centers can be obtained with high stereoselectivity under very mild conditions, while in the organic small molecule phosphonic acid catalyst system, the straight chain addition products can be obtained with high stereoselectivity For the branched chain addition products, the relative configuration of the products was confirmed by single crystal diffraction This method provides a very effective way for the chiral derivatization of pyrazolone compounds Relevant work was published in German Applied Chemistry (angew Chem., int ed 2016, DOI: 10.1002/anie.201610473), and was selected as the cover article.