Dearomative Dual Functionalization of Aryl Iodanes

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.

Intermolecular Dearomative 1,2‐Amination/Carbonylation via Nucleophilic Addition of Simple Amines to Arene π‐Bonds

“…In contrast to the significant advances in intermolecular aminofunctionalizations of alkenes, [3] alkynes, [4] and conjugated olefins, [5] much less success has been achieved in dearomative aminofunctionalizations of arenes due to the formidable challenges in overcoming the inherently low reactivity of aromatic systems and selectivity problems (Scheme 1A) [6] . Based on covalent modifications on arene rings, specific classes of arenes such as oxazoline‐substituted naphthalenes, [7] naphthylsulfilimines, [8] naphthamides, [9] aryl iodanes, [10] aryl sulfoxides [11] were successfully applied in dearomative aminofunctionalization reactions. Regarding simple and nonactivated benzene derivatives, breakthroughs have been made by Sarlah and co‐workers, giving a series of unprecedented dearomative aminofunctionalizations based on visible‐light‐mediated arene‐arenophile [4+2] cycloadditions (Scheme 1B) [12] .…”

Catalytic Three-component C–C Bond Forming Dearomatization of Bromoarenes with Malonates and Diazo Compounds

“…[5] Although a few dearomative reactions of inactive arenes as a limiting agent (including catalytic fashion) have recently emerged, the development of dearomative methods of a new class of arenes is still highly valuable. [6,7] Dearomative dicarbofunctionalization of benzenoids is a useful and step-economical methodology to build three-dimensional carbon frameworks. As representative examples using benzenoids as a limiting reagent, photo-induced intramolecular cycloadditions, [8] reactions of metal-arene complexes, [9] and nucleophilic dearomatizations [7,10] have been developed.…”

“…[6,7] Dearomative dicarbofunctionalization of benzenoids is a useful and step-economical methodology to build three-dimensional carbon frameworks. As representative examples using benzenoids as a limiting reagent, photo-induced intramolecular cycloadditions, [8] reactions of metal-arene complexes, [9] and nucleophilic dearomatizations [7,10] have been developed. Despite these advances, they still require the tedious preparation of metal-arene complexes and the presence of specific substituents such as oxazolines and iodanes.…”

Dearomative Allylation of Aromatic Cyanohydrins by Palladium Catalysis: Catalyst-Enhanced Site-Selectivity

“…Although electron-rich and electron-poor arenes can mostly be utilized as a limiting agent, [3] electron-neutral arenes are regarded as inactive arenes, usually requiring excess amounts in a reaction. [4,5] Generally, only nitroarenes [6] , aryl malonates [7] , and aryl iodanes [8] can be utilized for dearomative functionalizations as the limiting reagent.…”