スルホニル基の特性を活かした逐次的分子構築法の開発と応用

抄録

Organosulfone is a chemically-stable and versatile reagent in organic synthesis. The sulfonyl group is a strong electron-withdrawing substituent that permits the rapid functionalization of adjacent positions via deprotonation/alkylation, arylation, or conjugation addition reactions. However, after these reactions, removal of the sulfonyl group using highly reducing reagents is virtually the main choice. Therefore, the development of new methods to introduce various functional groups in the place of sulfonyl group will provide tremendous opportunities for straightforward synthesis of complex molecules. Recently our group has developed several new transformations of sulfone derivatives as reacting templates through α-functionalization followed by carbon-sulfonyl (C-SO₂) bond activation. To activate C-SO₂ bonds, we have established a new strategy focusing on the development of new catalysis/reagents and the design of sulfonyl groups. These methods could provide facile access to a variety of multiply-arylated structures such as di-, tri-, and tetraarylmethanes from stable and readily available reagents. In addition, the rapid preparation of α-fluorinated arylmethane derivatives by combination with selective α-fluorination of benzyl triflones was achieved, which opens up avenues for the development of unexplored biomolecules. Importantly, this work highlights the unique property of organosulfone to functionalize sp³ carbon centers in a modular manner.