Mechanistic study on silver(I)-catalyzed aminofluorination of unactivated alkenes

Abstract

A study has been performed on the mechanism for the Ag(I)‐catalyzed intramolecular aminofluorination of N‐arylpent‐4‐enamides with Selectfluor by means of density functional theory. According to the calculations, the whole catalytic cycle consists of a series of elementary reactions, including formation of the complex (IMC) of the substrate and Ag(H2O)+ (derived from the ligation of H2O to Ag(I)), oxidation of the complex IMC by Selectfluor, deprotonation, homolytic cleavage of the N–Ag(II) bond, intramolecular radical cyclization, and fluorine abstraction. It is suggested that the oxidation of the complex IMC should be the rate‐determining step and that the intramolecular radical cyclization determines the regioselectivity of the reaction. Different from that in the decarboxylative fluorination, herein, the deprotonation of the amide is initiated by Ag(II) rather than Ag(I).

Recent Advances in Silver‐Catalyzed Transformations of Electronically Unbiased Alkenes and Alkynes

“…Interestingly, the key Ag(III)-F intermediate proposed by Li was observed to be less possible from the perspective of computa-tional chemistry. [19] Duan et al then reported a decarboxylative acylfluorination of styrene derivatives using α-oxocarboxylic acid as an acyl radical precursor in 2014 (Scheme 8a). [20] Later, the Li group reported a concise carbofluorination reaction of alkenes using acetic acid as radical source, affording a wide range of γ-fluorinated carboxylic acids with good functional group tolerance (Scheme 8b).…”