Iodine-catalyzed C-H Bond Functionalization Of Azaarenes

N-heterocycles as an essential structural motif existing in a variety of biologically active substances has stimulated the development of new strategies and technologies for their synthesis. The field of C-H activation in organic chemistry has flourished during the last decade, which is especially attractive to organic chemists because C-H activation is “greener” than conventional methods. Therefore, the C-H functionalization of pyridine and quinoline derivatives has received significant attention from researchers engaged in drug synthesis and heterocyclic methodology development.With the advantages of high atomic economy, mild reaction conditions, easy separation, etc., iodine catalyzed C-H activation of azaarenes is “greener” than metal catalysts, and it also solves the problem of metal residual in drug synthesis.As the ongoing interest of our groups, we proposed the iodine-catalyzed functionalization of azaarenes.This dissertation is consisted of two parts: the first part is mainly about iodine-catalyzed oxidative benzylic C-H bond amination of azaarenes. With the reaction of anthranilamide with 2- methylquinoline as the model reaction, systematic optimization was carried out to establish the best reaction conditions as: catalyzed by iodine in DMSO under oxygen atmosphere. This reaction utilizes un-prefunctionalized alkylazaarenes as starting materials and proceeds under metal-free conditions with dioxygen as the terminal oxidant, thus is much “greener”than the previous reports.The second part involved iodine-catalyzed benzylation of azaarenes with(substituted) toluene. The best yield was obtained when the reaction proceeded with iodine as catalyst and TBP as the final oxidant. This method provided a complimentary approach for the Minisci type alkylation of N-heterocycles.