Rhodium-Catalyzed Heck-Type Coupling of Boronic Acids with Activated Alkenes in an Aqueous Emulsion

Abstract

Intermolecular couplings between arylboronic acids and activated alkenes catalyzed by a water-soluble tert-butyl amphos-rhodium complex were found to progress at room temperature and generated Heck-type products with high yields and excellent selectivity. Substitution on the alkene component encouraged the formation of products arising from a conjugate addition-protonation process. In the case of Heck product formation, it was necessary to add two equivalents of the alkene component whereby one equivalent is believed to act as a sacrificial hydride acceptor.

rhodium - Heck reaction - boron - olefination - alkylations

References

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Present address: Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA

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