Transition Metal Catalyzed Functional Group Directed C-H Bond Functionalization

Transition-metal-catalyzed functionalization of carbon-hydrogen bonds is a topic of recent intense interest. Chelation-assisted C-H bond activation is currently in widespread use in such transformations. Various transition metal complexes, in particular those of Ru, Rh, Pd, and Ir have been used as catalysts in chelation-assisted transformations of ortho C-H bonds.This dissertation mainly focused on the studies of relatively low-priced transition metal Ru, Co catalyzed C-H bond activation, which include:We used CONH(OMe) of N-methoxybenzamides as an oxidizing directing group with selective formation of the isoquinolone motif via [RuCl2(p-cymene)]2catalyzed C-H bond activation under mild reaction conditions in high yield without using any external oxidant. Many important functional groups on the aromatic ring of benzamides were compatible. The reaction showed broad substrate tolerance with internal alkynes. This reaction provides a convenient and practical method on the topic of isoquinolone synthesis for using the inexpensive Ru as the catalyst.We developed a method using [RuCl2(p-cymene)]2as the catalyst to construct polycyclic amides through oxidative C-H bond activation, cyclo-addition of alkynes to isoquinolones. More significantly, we obtained the intermediates of each reaction steps including cyclo-metalation, insertion of alkynes and reductive elimination for the first time which helps us to have a good understanding of the reaction mechanism.We developed a method for the arylation of alkenes. Arylation of2-Alkenylpyridines with Phenyl Grignard Reagents through cobalt catalyzed C-H bond activation was realized under mild reaction conditions. This methodology adds to the rapidly growing cobalt catalyzed C-H activaton reactions.