Dehvdrogenative Cross-coupling Reaction Via The Activation Of C-H Bond Adjacent To Oxygen Atom And Nitrogen Atom

Over the past few decades, Carbon-Carbon (C-C) and carbon-heteroatom (C-Y) bond formation are among the most important processes in chemistry because they widely exist in natural products, pharmaceutical industry, and materials science and provide key steps in building more complex molecules from simple precursors.The C-C bond formation via deyhrogenative cross-coupling (DCC) reactions has emerged as one of the most important topics in the field of metal-catalyzed C-H bond activation. It provides the pillar for the next-generation of chemical synthesis with an eye on green chemistry due to various benefits, such as eliminating prefunctionaliza-tion step of coupling substrates, lower cost and minimized waste.This dissertation mainly contains the following sections.The first chapter is a review of a-C(sp3)-H bond functionalization adjacent to oxygen and nitrogen atom with carbon and heteroatom pronucleophile through DCC methods.These reactions are arranged on the base of oxidative coupling between a-C(sp3)-H bonds adjacent to an oxygen and nitrogen atom with other C-H bond including (sp3, sp2 and sp) and heteroatom(C-X) include (N, O and P) and categorized by metal and non-metal catalyzed DCC reactions respectively.The second chapter describes a C(sp3)-C(sp2) bond formation between pyridines and ethers via DCC reaction in the presences of Sc(OTf)2 and oxidant DTBP. A highly chemoselective and regioselective DCC reaction of unactivated pyridines with cyclic or acyclic ethers has been developed to give the corresponding coupled pyridines in satisfactory yields.The DCC reaction affords an efficient and greener synthesis for a range of new pyridines derivatives. A possible mechanism involving radical substitution is proposed.The third chapter is about synthesis of a-aryl a-amino acid ester from oxidative coupling between N-aryl glycine esters and phenols or phenol derivatives under the conditions of using Cu(OAc)2 and DTBP as catalyst and oxidant respectively. A series of new compound of N-aryl glycine esters containing phenols or its derivatives can be synthesized with highly ortho regioselectivities in moderate to excellent yields.A possible mechanism involving aromatic electrophilic substitution is proposed.