Total Synthesis Of (–)-Berkelic Acid And Syntheses Of Novel Axially Chiral Biaryl Catalysts Via Pd/NBE Cooperative Catalysis

Since its discovery in 1997,the Catellani reaction has become an important organic synthesis methodology over the past two decades.With the efforts of many chemists,the intension and application of Catellani reaction has been greatly enriched and widely developed respectively.This reaction is a multi-components cascade reaction,features a modular synthesis,which is consistent with the concept of highly efficient synthesis in modern organic synthesis.This dissertation focuses on the efficient synthesis of bioactive natural products and other aromatic functional molecules,which mainly includes the following two parts:1.We developed a new Catellani reaction with chiral epoxide as a dualfunctionalized alkylation reagent.Using this Catellani reaction/oxa-Michael cascade reaction,we have quickly constructed isochroman scaffold in(–)-berkelic acid.In addition,a one-pot deprotection/spiroacetalization has been developed for the construction of the tetracyclic core of(–)-berkelic acid.Notably,four new stereocenters are established from one existing chiral center with excellent stereocontrol during this challenging process.Moreover,a late-stage Ni-catalyzed reductive coupling has been used to introduce the lateral chain.Finally,we have accomplished a concise total synthesis of(–)-berkelic acid in eight linear steps.2.We developed a Pd/chiral norbornene cooperatively catalyzed threecomponents Catellani reaction for the construction of novel axial chirality biaryl ligands,such as phosphine-alkene ligand,dicarboxylic acid ligand,pinacol ligand and diene ligand.At the same time,the catalytic performance of axially chiral P/olefin hybrid ligands have been evaluated.These novel axially chiral ligands have been demonstrated to be highly efficient in palladium-catalyzed asymmetric allylation reaction.This method features a wide variety of substrates,good functional group compatibility,excellent enantioselectivities,step economy and scalability.It also provides a new approach for the construction of diversified axial chirality biaryls.