Photogenerated Neutral Nitrogen Radical Catalyzed Bifunctionalization of Alkenes

Chemistry. 2019 Jun 18;25(34):8024-8029. doi: 10.1002/chem.201901665. Epub 2019 May 21.

Abstract

Alkene bifunctionalizations are powerful tools for the rapid construction of structurally complex and valuable scaffolds, and such reactions typically involve the use of transition-metal catalysts or organocatalysts. Here, we report for the first time a photogenerated neutral nitrogen radical catalyzed intermolecular alkene bifunctionalization by using allyl sulfones as the source of both the carbon and the sulfone functionalities under mild conditions. The key to the success of this protocol involves the visible-light-mediated photocatalytic in situ generation of a nitrogen-centered radical from the N-(2-acetylphenyl) benzenesulfonamide catalyst, and its activation of the allyl sulfones to generate reactive species. The preliminary control experiments supported the postulated mechanism.

Keywords: alkene bifunctionalization; nitrogen radicals; photocatalysis; sulfones; visible light.