Visible‐Light‐Catalyzed N‐Radical‐Enabled Cyclization of Alkenes for the Synthesis of Five‐Membered N‐Heterocycles

Abstract

Five-membered N-heterocycles play an important role in organic synthesis and material chemistry, as they are widespread through pharmaceutical molecules and natural products. Chemists have developed many synthetic strategies for constructing five-membered N-heterocycles from N-centered radicals, but the availability of mild and green methods for these transformations is still limited. The cyclization of visible-lightgenerated N-centered radicals with alkenes has emerged as a powerful tool to enable these chemical transformations in recent years. Through chosen representative examples, the significant developments in this promising field were outlined, including the selection of catalysts, substrate scope, mechanistic understanding (especially density functional theory calculations), and applications. The contents of this Minireview are categorized by intramolecular cyclization and intermolecular Ncentered radical addition/cyclization reactions.

Trifunctionalization of Cinnamyl Alcohols Provides Access to Brominated α,α-Difluoro-γ-lactones via a Photoinduced Radical–Polar–Radical Mechanism

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Asymmetric synthesis of chiral imidazolidines by merging copper and visible light-induced photoredox catalysis

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