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N-Heterocyclic carbene based catalytic platform for Hauser-Kraus annulations.

ABSTRACT: The venerable Hauser-Kraus annulation is an effective and convergent method for generating oxygenated polycyclic aromatic compounds. Despite its application in complex molecule synthesis, the harsh and strongly basic conditions can limit its utility in more functionalized molecular settings. We have developed the first catalytic Hauser-Kraus annulation based on N-heterocyclic carbene catalysis that proceeds under milder conditions. We demonstrate the scope of the transformation in the presence of several functional groups. We also propose a concerted mechanism for the annulation that proceeds through a non-canonical Breslow intermediate.

SUBMITTER: Sharique M

PROVIDER: S-EPMC8159274 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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N-Heterocyclic carbene based catalytic platform for Hauser-Kraus annulations.

Sharique Mohammed M Tambar Uttam K UK

Chemical science 20200630 27

The venerable Hauser-Kraus annulation is an effective and convergent method for generating oxygenated polycyclic aromatic compounds. Despite its application in complex molecule synthesis, the harsh and strongly basic conditions can limit its utility in more functionalized molecular settings. We have developed the first catalytic Hauser-Kraus annulation based on N-heterocyclic carbene catalysis that proceeds under milder conditions. We demonstrate the scope of the transformation in the presence o ...[more]

PMID: 34123009

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