Development of Selective Remote Functionalization Reactions Using Chain Walking of Palladium Catalysts

Remote functionalization of organic molecules has been attracting increasing attention, because it provides a unique way to introduce or convert functional groups at unconventional positions. Chain walking of metal catalysts on alkyl chains is one of the powerful strategies to achieve effective remote functionalization by migrating reactive groups to positions distant from where the reactive functional groups in the substrates are originally present. Since we reported the use of nondissociative chain walking of the metal catalyst for selective conversion of remote unreactive C (sp3)-H bonds, by developing the palladium-catalyzed cycloisomerization of 1,n-dienes to form five-membered rings, we have been working on the use of nondissociative chain walking for various remote functionalization reactions such as hydrofunctionalizative and diborylative cyclizations of 1,n-dienes, asymmetric cycloisomerization, and selective long-distance isomerization of alkenes via chain walking. In this account, I would like to describe our efforts in the reaction developments as well as the features of the nondissociative chain walking mechanism beneficial for organic synthesis.