Researchers of the ZIOC published a review on [4+1]-annulation reactions
Five-membered heterocycles containing one or more heteroatoms are important intermediates in organic synthesis on the way to bioactive and natural compounds. In recent years, the [4+1]-annulation approach has been actively developed for the construction of such cycles, which allows stereoselective assembly of polysubstituted five-membered rings from available starting compounds in one synthetic step. It should also be noted that this methodology is compatible with asymmetric catalysis, which allows the process to be carried out enantioselectively.
Scientists from the Laboratory of Organic and Metal-Organic Nitrogen-Oxygen Systems of the Zelinsky Institute published a review on the latest achievements in the field of [4+1]-annulation reactions. The material is divided into chapters in accordance with the structure of the starting substances: sulfonium, sulfoxonium, and ammonium ylides; diazo compounds, and carbenes. In addition to traditional ionic transformations, the review considers transformations proceeding through the radical pathway under conditions of photoredox catalysis and in the coordination sphere of metals. Special attention is paid to organocatalytic reactions using chiral starting structures.
Pavel Yu. Ushakov, Sema L. Ioffe, Alexey Yu. Sukhorukov Recent advances in the application of ylide-like species in [4 + 1]-annulation reactions: an updated review Org. Chem. Front., 2022, accepted manuscript. DOI: 10.1039/d2qo00698g.