Synthesis of Hexahydromdoles by Intramolecular C_(sp~3)-H Alkenylation: Application to the Synthesis of the Core of Aeruginosas

摘要

The functionalization of C—H bonds has recently emerged as an atom- and step-economical alternative to more traditional synthetic methods based on functional group transformation, which often require multistep sequences.In particular, transition metal catalysis has been shown to be a powerful tool to functionalize otherwise unreactive C~(sp~2)—H and C_(sp~3)-H bonds. These advances have enabled the construction of a variety of carbon-carbon and carbon-heteroatom bonds with great efficiency and selectivity, even in structurally complex organic molecules.In this context, our recent research has focused on the intramolecular arylation of unactivated C_(sp~3)—H bonds with aryl halides under palladium(0) catalysis/31 to give synthetically useful polycylic molecules such as benzocyclobutenes (Scheme 1a). Unlike C_(sp~3)—H arylations with aryl halides, C_(sp~3)—H alkenylations with alkenyl halides are very scarce.