Title: New Transformations of Organosulfone through Carbon–Sulfonyl Bond Activation

Sulfur is found in diverse functional materials, natural products, and biologically active molecules. Among organosulfur compounds, organosulfones stand out as having high chemical stability and strong electronwithdrawing ability, which can dramatically change reactivities and electronic properties of molecules. However, Compared with (pseudo)halides, the sulfonyl group has been recognized to be less reactive, thereby receiving sparse attention as a leaving group in organic synthesis. Since 2013, we have focused on sulfones as new reacting templates for straightforward synthesis of

organic molecules through a-functionalization followed by carbon–sulfonyl bond activation. Transiton-metal catalysts were found to be effective to promote crosscouplings and radical reactions using sulfones, providing a structurally diverse products in a modular manner. We demonstrated that not only the development of new catalysts and reagents but also the design of sulfonyl group is critically important to activate carbon–sulfonyl

bonds. This work highlights the unique property of sulfonyl group as a transient directing group to construct valuable molecules by sequential functionalizations of sp3 carbon centers.