Acid-catalyzed oxidative radical addition of ketones to olefins.
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.
Max-Planck-Institut für Kohlenforschung, Kaiser Wilhelm-Platz 1, 45479 Mülheim an der Ruhr (Germany) http://www.kofo.mpg.de.
Bertrand
B
Schweitzer-Chaput
Joachim
J
Demaerel
Hauke
H
Engler
Martin
M
Klussmann
ketones; multicomponent reactions; organocatalysis; peroxides; radicals