Ruthenium-catalyzed Double Directing Group Directed C-H Activation/Dearomatization Reaction

With the increasing demand for precise synthesis of compounds,the directing group directed C-H functionalization reactions has been rapidly developed in recent years.This new strategy can selectively functionalize the inert C-H bonds,and it is regarded as a elegant and efficient ways in synthetic chemistry.In the past decades,chemists applied this strategy to realize the C-H activation/dearomatization reaction of phenolic compounds.This strategy can synthesize a lot of spiral ring molecules,which are widely found in drug molecules,functional materials and natural products.In this thesis,a highly regioselective Ru(II)-catalyzed [3+2] spiroannulation of 1-aryl-2-naphthols with internal alkynes was developed by using a novel double directing group strategy.This method was compatible with many functional groups,thus affording a variety of sterically congested spirocyclic molecules in high yields.The specific content is as follows:The first chapter mainly summarizes the following two aspects:(1)The research progress of Ru-catalyzed directing group-directed C-H functionalization reaction,and the advantages or disadvantages of existing methods are introduced.(2)The progress of transition metal catalyzed C-H activation/dearomatization of phenolic compounds.The second chapter introduces the research of Ru-catalyzed double directing group-directed C-H bond activation/dearomatization reaction.This new reactions is characterised by the introduction of acetylamino group as a second directing group,which can reverse conventional regiochemistry of the previously reported [3+2] spiroannulations between 1-aryl-2-naphthols and internal alkynes.Besides,this method was compatible with many functional groups,and it can maintain high efficiency and regioselectivity at the same time.The control experiment clearly verified the power of this new double directing strategy for the target transformation...