Cerium‐Catalyzed Reaction of β‐Dicarbonyl Compounds with Styrene and Atmospheric Oxygen
The cerium-catalyzed C−C coupling reaction of carbo- and heterocyclic β-dicarbonyl compounds 1 with styrenes 4, using oxygen (air) as the oxidant, at ambient temperature, is reported. The reaction afforded a mixture of diastereoisomeric hydroperoxides 5 which could be transformed into the unique dioxo compounds 6 by disproportionation of the peroxo function under treatment with acetyl chloride/pyridine. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)