Iron-Catalyzed Aminative Cyclization/Intermolecular Homolytic Aromatic Substitution Using Oxime Esters and Simple Arenes.

Chem Asian J

Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan.

Published: February 2018

AI Article Synopsis

  • A novel method allows for the intermolecular C-H alkylation of simple arenes using an iron catalyst, triggered by breaking an N-O bond in a specific setup involving oxime esters.
  • Various types of arenes, such as electron-rich, electron-poor, and heteroarenes, can participate in this reaction.
  • The process involves alkyl radicals and a mechanism known as homolytic aromatic substitution (HAS) to produce the final arylation products.

Article Abstract

Intermolecular C-H alkylation of simple arenes in the presence of an iron catalyst has been achieved in a cascade manner with an aminative cyclization triggered by N-O bond cleavage of an alkene-tethered oxime ester. Various arenes, including electron-rich and electron-poor arenes, and heteroarenes can be employed in the reaction system. Regioselectivity and radical trapping experiments support the involvement of alkyl radical species, which undergo a homolytic aromatic substitution (HAS) to afford the arylation products.

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http://dx.doi.org/10.1002/asia.201701634DOI Listing

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