Nickel Catalyzed Reductive Alkylation And Amidation Reactions Of Alkenyl Acetates

Transition metal catalyzed reductive cross-coupling have become an important,rapid and precise protocol for forging C–C or C-X bonds.The advantageous of this method includes the excellent functionality tolerance,high step-economy and unique chemical selectivity that is complementary to traditional coupling methods.Currently,this method is mainly limited to the conversion of halogenated hydrocarbons or halogenated hydrocarbon analogs,which has restricted the further development for cross-electrophile coupling reaction.Owing to nitrogen-or oxygen-containing compounds widespread availability and easy preparation,thus transition metalcatalyzed reductive cross-coupling involving C-O electrophiles or C-N electrophiles were particularly fascinating.If this reaction can be successfully realized,it will greatly expand the scope of reductive cross-coupling reaction in organic synthesis.Alkenyl acetates can be easy preparation from ketones by a transesterification method.The compound has many advantages such as easy preparation,high stability,small leaving group and eco-friendly.At presently,transition metal-catalyzed coupling reactions involving alkenyl acetates mainly include: Suzuki-Miyaura coupling,Negishi coupling,Kumada-Tamao-Corriu coupling and C-H alkenylation reactions.However,transition metal-catalyzed(asymmetric)reductive coupling reactions involving alkenyl acetates are rarely reported.This thesis has focused on the studies for(asymmetric)reductive coupling reaction of alkenyl acetates by nickel catalysis,and it includes the following sections:Chapter 1.This chapter briefly introduces the properties of nickel and nickel complexes.And then,the progress of nickel catalyzed reductive cross-coupling involving alkenyl electrophiles are detailed summarized.Chapter 2.This chapter focuses on the reductive benzylation/arylation of alkenyl acetetes by nickel catalysis.A series of allyl compounds,alkenyl-aryl compounds and diarylmethane compounds were easily prepared for this reaction.Subsequently,preliminary mechanistic experiments revealed that benzylic ammonium salts was activated by radical mechanism.Chapter 3.This chapter focuses on the reductive alkylation of alkenyl acetetes by nickel catalysis.To the best of our knowledge,this is the first nickel-catalyzed reductive cross-coupling of alkenyl acetates with alkyl halohydrocarbons.The reaction is compatible with primary alkyl halohydrocarbons and secondary alkyl halohydrocarbons.Further mechanistic studies revealed that the monovalent nickel species was the active catalyst for this reaction.Chapter 4.This chapter focuses on the(asymmetric)reductive conjugated addition of alkenyl acetetes by nickel catalysis.A series of unsaturated diketone compounds were prepared for this reaction.Owing to the unsaturated diketone compounds widely exists in pharmaceutical molecules and natural products,there is no doubt that its has important synthetic value.To the best of our knowledge,this is the first transition metalcatalyzed asymmetric cross-coupling involving alkenyl acetates.Preliminary mechanistic studies indicated that the reaction underwent a reductive Heck process.Chapter 5.This chapter focuses on the reductive amidation of alkenyl acetetes by nickel catalysis.And a series of acrylamide were constructed for this reaction.Owing to the acrylamide widely exists in pharmaceutical molecules,biological proteins,functional materials and natural products,there is no doubt that its has important synthetic value.Except that,the reaction has a broad substrate scope.And then,we also synthesis of AG analogs drug molecules.