Rh(?)-catalyzed Imine-directed C-H Activation And Its Application In The Synthesis Of Heterocyclic Compounds

Organic reations that involves the direct functionalization of non-activated C-H bonds represent an attractive class of transformations which maxize atom-and step-economy,and simplify chemical synthesis.Due to the high stability of the C-H bond,however,these processes have most often required harsh reaction conditions,mild C-H activation can be achieved through judicious selection of directing groups,reation coupling partners and catalytic systems.In this paper,we mainly discuss the activation of C-H bonds under mild conditions and the application for synthesis of heterocyclic compounds based on Rh???catalyzed imine as directing group C-H bond activation.The main contents include:In the first chapter,we present mild metal-catalyzed C-H activation:examples and concepts.In the second chapter,we report the preliminary result of an efficient double C-N bond formation sequence to prepare highly substituted quinazolines utilizing benzimidates and dioxazolones under the catalytic redox-neutral[Cp^*RhCl₂]₂/AgBF₄ system,where dioxazolone could work as an internal oxidant to maintain the catalytic cycle meanwhile as a coupling partner for access to the heterocycle.In the third chapter,we developed an efficient route for the synthesis of isoquinolines from readily available benzimidates and diazodiesters via Rh?III?-catalyzed C-H bond activation,followed by intramolecular cyclization.diazodiesters as a C=C double bond source into the newly formed heterocycles were first demonstrated.Additionally,the Rh???-catalyzed direct C-H activation/cyclization of benzimidates with diazoketoesters is also described.