Photocatalytic C–H Activation and Amination of Arenes with Nonactivated N-Hydroxyphthalimides Involving Phosphine-Mediated N–O Bond Scission

Abstract

Herein, we reported a metal-free photoredox/phosphine-catalyzed C–H amination of arenes. This allows for concise synthesis of highly functionalized N-arylphthalimides from readily available N-hydroxyphthalimides directly, without the preparation of activated N-hydroxyphthalimide intermediates. Mechanistic studies reveal that the radical is produced via phosphine-mediated N–O bond scission.

Visible-Light-Driven C–H Imidation of Arenes and Heteroarenes by a Phosphonium Ylide Organophotoredox Catalyst: Application to C–H Functionalization of Alkenes

“…In particular, since the N -phthaloyl group can be readily derivatized to the corresponding anilines, there are several reports on catalytic arene C–H phthalimidation with the use of transition metals. , Aromatic substitution reactions by nitrogen-centered radicals are also well-known approaches toward the direct C–H amination . Due to growing interest in sustainable chemistry, photocatalytic imidation involving the radical has emerged recently. , In 2014, Sanford et al successfully revealed that a phthalimidyl radical could be generated from N -acyloxyphthalimide via the single electron transfer mechanism in the presence of Ir­(ppy) 3 under visible-light irradiation . The electrophilic radical undergoes addition to arenes to afford the C–H imidated products.…”

Visible Light-Driven α-Diazoketones as Denitrogenated Synthons: Synthesis of Fluorinated N-Heterocycles via Multicomponent Cyclization Reactions

“…On the basis of the experimental results presented above and the literature, , we have proposed the plausible reaction mechanism of this multicomponent cyclization reaction (Scheme ). The excited state [Ir III ]* reduces (ICF 2 CF 3 ) 3a to (•CF 2 CF 3 ) 3a′ and [Ir IV ].…”