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Nondirected, Cu-Catalyzed sp3 C-H Aminations with Hydroxylamine-Based Amination Reagents: Catalytic and Mechanistic Studies.

ABSTRACT: This work demonstrates the use of hydroxylamine-based amination reagents RSO2NH-OAc for the nondirected, Cu-catalyzed amination of benzylic C-H bonds. The amination reagents can be prepared on a gram scale, are benchtop stable, and provide benzylic C-H amination products with up to 86% yield. Mechanistic studies of the established reactivity with toluene as substrate reveal a ligand-promoted, Cu-catalyzed mechanism proceeding through Ph-CH2(NTsOAc) as a major intermediate. Stoichiometric reactivity of Ph-CH2(NTsOAc) to produce Ph-CH2-NHTs suggests a two-cycle, radical pathway for C-H amination, in which the decomposition of the employed diimine ligands plays an important role.

SUBMITTER: Wang A

PROVIDER: S-EPMC6585460 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Nondirected, Cu-Catalyzed sp3 C-H Aminations with Hydroxylamine-Based Amination Reagents: Catalytic and Mechanistic Studies.

Wang Anqi A Venditto Nicholas J NJ Darcy Julia W JW Emmert Marion H MH

Organometallics 20170323 7

This work demonstrates the use of hydroxylamine-based amination reagents RSO2NH-OAc for the nondirected, Cu-catalyzed amination of benzylic C-H bonds. The amination reagents can be prepared on a gram scale, are benchtop stable, and provide benzylic C-H amination products with up to 86% yield. Mechanistic studies of the established reactivity with toluene as substrate reveal a ligand-promoted, Cu-catalyzed mechanism proceeding through Ph-CH2(NTsOAc) as a major intermediate. ...[more]

PMID: 31223182

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