DBU-Catalyzed Michael Reaction of Enones with 1,3-Diketones and the Subsequent Iodine-Mediated Transformation of the Adducts to Polysubstituted Phenols

Abstract

An efficient DBU-catalyzed Michael reaction of enones with 1,3-diketones has been developed for the gram-scale preparation of the Michael adducts. It is attractive that most of the adducts can be obtained with high purity through simple filtration. A convenient I2-mediated transformation of the adducts to polysubstituted phenols has also been exploited. This conversion is remarkable with the cyclization and aromatization processes by using DBU as the base and I2 as the oxidant. Furthermore, hydroxylated (E)-stilbene derivatives can be easily prepared by using this method. The readily available starting materials, metal-free and mild conditions make this approach simple and practical.