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Mechanistic Pathways in Amide Activation: Flexible Synthesis of Oxazoles and Imidazoles.

ABSTRACT: The preparation of substituted aminooxazoles and aminoimidazoles from ?-arylamides and ?-aminoamides through triflic anhydride-mediated amide activation is reported. These reactions proceed via the intermediacy of nitrilium adducts and feature N-oxide-promoted umpolung of the ?-position of amides as well as a mechanistically intriguing sequence that results in sulfonyl migration from nitrogen to carbon. Quantum-chemical mechanistic analysis sheds light on the intricacies of the process.

SUBMITTER: Di Mauro G

PROVIDER: S-EPMC5525102 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Mechanistic Pathways in Amide Activation: Flexible Synthesis of Oxazoles and Imidazoles.

Di Mauro Giovanni G Maryasin Boris B Kaiser Daniel D Shaaban Saad S González Leticia L Maulide Nuno N

Organic letters 20170713 14

The preparation of substituted aminooxazoles and aminoimidazoles from α-arylamides and α-aminoamides through triflic anhydride-mediated amide activation is reported. These reactions proceed via the intermediacy of nitrilium adducts and feature N-oxide-promoted umpolung of the α-position of amides as well as a mechanistically intriguing sequence that results in sulfonyl migration from nitrogen to carbon. Quantum-chemical mechanistic analysis sheds light on the intricacies of the process. ...[more]

PMID: 28703599

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