Acid-catalyzed oxidative radical addition of ketones to olefins.

Angew Chem Int Ed Engl

Max-Planck-Institut für Kohlenforschung, Kaiser Wilhelm-Platz 1, 45479 Mülheim an der Ruhr (Germany) http://www.kofo.mpg.de.

Published: August 2014

Based on a mechanistic study, we have discovered a Brønsted acid catalyzed formation of ketone radicals. This is believed to proceed via thermally labile alkenyl peroxides formed in situ from ketones and hydroperoxides. The discovery could be utilized to develop a multicomponent radical addition of unactivated ketones and tert-butyl hydroperoxide to olefins. The resulting γ-peroxyketones are synthetically useful intermediates that can be further transformed into 1,4-diketones, homoaldol products, and alkyl ketones. A one-pot reaction yielding a pharmaceutically active pyrrole is also described.

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http://dx.doi.org/10.1002/anie.201401062DOI Listing

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