Utilization of palladium-catalyzed C-C and C-N bond formation reactions in the synthesis of six-membered oxygen heterocycles

摘要

In this contribution a brief overview will be given on the recent results of our research group achieved in the fields of cross-coupling reactions of chromones, flavones and coumarins. Efficient methods have been developed to alkenylation and alkynylation of both Ring A and B of chromones and flavones by Heck and Sonogashira reaction, respectively. These approaches were successfully applied for the synthesis of hydroxylated derivatives with resacetophenone- or floracetophenone-type substitution pattern which are typical for naturally occurring compounds. Moreover, the ring closure of double or triple bonds and the adjacent hydroxyl group allows the synthesis of various interesting tricyclic compounds.