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Cation Radical-Accelerated Nucleophilic Aromatic Substitution for Amination of Alkoxyarenes.

ABSTRACT: Nucleophilic aromatic substitution (S_NAr) is a common method for arene functionalization; however, reactions of this type are typically limited to electron-deficient aromatic halides. Herein, we describe a mild, metal-free, cation-radical accelerated nucleophilic aromatic substitution (CRA-S_NAr) using a potent, highly oxidizing acridinium photoredox catalyst. Selective substitution of arene C-O bonds on a wide array of aryl ether substrates was shown with a variety of primary amine nucleophiles. Mechanistic evidence is also presented that supports the proposed CRA-S_NAr pathway.

SUBMITTER: Venditto NJ

PROVIDER: S-EPMC7476680 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Cation Radical-Accelerated Nucleophilic Aromatic Substitution for Amination of Alkoxyarenes.

Venditto Nicholas J NJ Nicewicz David A DA

Organic letters 20200602 12

Nucleophilic aromatic substitution (S<sub>N</sub>Ar) is a common method for arene functionalization; however, reactions of this type are typically limited to electron-deficient aromatic halides. Herein, we describe a mild, metal-free, cation-radical accelerated nucleophilic aromatic substitution (CRA-S<sub>N</sub>Ar) using a potent, highly oxidizing acridinium photoredox catalyst. Selective substitution of arene C-O bonds on a wide array of aryl ether substrates was shown with a variety of prima ...[more]

PMID: 32484681

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