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Updated: Nov 2, 2025
Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
meta-Selective olefination of fluoroarenes with alkynes using CO2 as a traceless directing group
Andrew R A Spencer1, Rishi Korde1, Marc Font1
1School of Chemistry, University of Manchester Oxford Road Manchester M13 9PL UK igor.larrosa@manchester.ac.uk.
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.
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