Synthesis of Allylic Sulfones via Generation of Metal Π‐Allyl Complexes in Metal‐Catalyzed Sulfonylation

Allyl sulfones are common motifs in many drugs and natural products, exhibiting a wide range of biological activities such as anticancer and antibacterial properties, etc. An overview is provided on the synthesis of allylic sulfones via generation of metal π-allyl complexes in metal-catalyzed sulfonylation over the period from 2020 to the present. The generation process of metal π-allyl complexes is introduced from the perspective of reaction mechanism and the reaction processes such as nucleophilic substitution, insertion of SO₂, and reductive elimination involving metal π-allyl complexes is discussed. In order to effectively organize this study, several metal π-allyl intermediates will be reviewed and can be divided into i) generation of palladium π-allyl complexes in palladium-catalyzed sulfonylation and ii) generation of other metal π-allyl complexes in other metal-catalyzed sulfonylation.