Catalytic Dehydrogenative C–H Imidation of Arenes Enabled by Photo-generated Hole Donation to Sulfonimide

Abstract

In light of the importance of arylamine derivatives in organic materials, pharmaceuticals, and agrochemicals, the development of efficient aromatic C–H amination has long been sought after. Although many attempts have been made to achieve dehydrogenative C–H amination, the low reactivity of simple arenes renders equimolar coupling with amine derivatives a formidable task in synthetic chemistry. Herein, we report equimolar C–H/N–H coupling of arenes and sulfonimides through dehydrogenative aromatic imidation. This was accomplished by means of a ruthenium-based photoredox mediator that employed the arene as the limiting reagent. A wide range of arenes, such as polycyclic aromatic hydrocarbons and heteroarenes, as well as a variety of sulfonimides, were applicable to the reaction. This electrochemistry-based mechanistic study has uncovered that the coupling reaction is initiated by the oxidation of sulfonimides by the ruthenium catalyst.