Palladium-Catalyzed Three-Component Diaryl Sulfone Synthesis Exploiting the Sulfur Dioxide Surrogate DABSO

摘要

Aryl, heteroaryl, and alkenyl sulfones play a prominent role in organic and medicinal chemistry. Not only are they versatile intermediates in organic synthesis, but they are also of particular pharmaceutical relevance, and exhibit an extensive and broad range of biological activities (Scheme l). In addition, sulfone-containing polymers dis- play novel properties as materials. Although there are a variety of methods known for the preparation of sulfones, the majority of these processes feature associated limitations. For example, oxidation of the corresponding sulfide relies on functional-group compatibility with oxidizing agents and the availability of catalysts to promote selectivity for sulfone formation over sulfoxide formation; in addition, the preparation of the required sulfide substrate often involves the use of foul-smelling thiols.Friedel-Crafts-type sulfonylation of arenes is limited not only by the generally harsh reaction conditions, but also by the inherent regioselective bias imposed by the electronic and steric properties of the arene substrate.