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meta-Selective olefination of fluoroarenes with alkynes using CO₂ as a traceless directing group.

ABSTRACT: Over the last few decades C-H olefination has received significant interest, due to the importance and usefulness of aryl olefins both as synthetic targets and intermediates. While a wide range of ortho-olefination protocols have been developed, only a small number of meta-olefinations are currently available. Importantly, the most common approach to meta-olefination, using a large meta-directing template, is not suitable for substrates such as fluorobenzenes, which cannot be derivatised. We report that the meta-selective olefination of fluoroarenes can be achieved via the use of CO₂ as a traceless directing group, which can be easily installed and removed in a one-pot process. Furthermore, this approach avoids the use of stoichiometric Ag(i)-salts, commonly used in C-H olefinations, and affords complete meta- over ortho/para-regioselectivity.

SUBMITTER: Spencer ARA

PROVIDER: S-EPMC8152615 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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meta-Selective olefination of fluoroarenes with alkynes using CO2 as a traceless directing group.

Spencer Andrew R A ARA Korde Rishi R Font Marc M Larrosa Igor I

Chemical science 20200331 16

Over the last few decades C-H olefination has received significant interest, due to the importance and usefulness of aryl olefins both as synthetic targets and intermediates. While a wide range of ortho-olefination protocols have been developed, only a small number of meta-olefinations are currently available. Importantly, the most common approach to meta-olefination, using a large meta-directing template, is not suitable for substrates such as fluorobenzenes, which c ...[more]

PMID: 34122883

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