Dearomative Dual Functionalization of Aryl Iodanes

Angew Chem Int Ed Engl. 2019 Nov 25;58(48):17210-17214. doi: 10.1002/anie.201909019. Epub 2019 Oct 15.

Abstract

Herein we describe the dearomatization of aryl iodanes through an unprecedented "rearrangement/addition" sequence. The process consists of two stages. First, a rapid [3,3] sigmatropic rearrangement of the aryl iodane with an α-stannyl nitrile affords a highly electrophilic dearomatized intermediate at -78 °C. A low-temperature rearrangement then enables the unstable dearomatized species to be trapped in situ with various nucleophiles. As a consequence, the reaction not only breaks the aromaticity of the aryl iodane but also sequentially installs two different functional groups, thus resulting in a polysubstituted alicyclic product.

Keywords: dearomatization; electrophilic activation; hypervalent compounds; iodine; sigmatropic rearrangement.