- meta-Selective olefination of fluoroarenes with alkynes using CO2as a traceless directing group
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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 ofortho-olefination protocols have been developed, only a small number ofmeta-olefinations are currently available. Importantly, the most common approach tometa-olefination, using a largemeta-directing template, is not suitable for substrates such as fluorobenzenes, which cannot be derivatised. We report that themeta-selective olefination of fluoroarenes can be achievedviathe use of CO2as 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 completemeta- overortho/para-regioselectivity.
- Font, Marc,Korde, Rishi,Larrosa, Igor,Spencer, Andrew R. A.
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p. 4204 - 4208
(2020/05/13)
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- A simple, multidimensional approach to high-throughput discovery of catalytic reactions
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Transition metal complexes catalyze many important reactions that are employed in medicine, materials science, and energy production. Although high-throughput methods for the discovery of catalysts that would mirror related approaches for the discovery of medicinally active compounds have been the focus of much attention, these methods have not been sufficiently general or accessible to typical synthetic laboratories to be adopted widely. We report a method to evaluate a broad range of catalysts for potential coupling reactions with the use of simple laboratory equipment. Specifically, we screen an array of catalysts and ligands with a diverse mixture of substrates and then use mass spectrometry to identify reaction products that, by design, exceed the mass of any single substrate. With this method, we discovered a copper-catalyzed alkyne hydroamination and two nickel-catalyzed hydroarylation reactions, each of which displays excellent functional-group tolerance.
- Robbins, Daniel W.,Hartwig, John F.
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p. 1423 - 1427
(2012/01/03)
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