Research On Rhodium-catalyzed Asymmetric Cascade Cyclization Of Oxabenzonorbornadienes

The chiral di-and tetrahydronaphthalene skeletons are found in many biologically active natural products and drug molecules,and transition metal-catalyzed asymmetric reaction of oxa-and azabenzonorborneadienes is an important method to synthesize these two types of units with highly enantioselectivity.Therefore,asymmetric reaction of oxa-and azabenzonorborneadienes have attracted continuous interest and extensive study by a lot of chemists.In this dissertation,we had realized the rhodium-catalyzed asymmetric ring opening/cyclization of oxabenzonorbornadienes with phosphorus ylides or vinylnaphthols.This dissertation was divided into three chapters:Chapter 1: Research progress of transition metal-catalyzed asymmetric reaction of oxabenzonorborneadienes were detailedly reviewed.Chapter 2: Rhodium-catalyzed asymmetric ring opening/cyclopropanation of oxabenzonorbornadienes with phosphorus ylides was first achieved to synthesize benzonorcaradienes with excellent diastereoselectivity and highly enantioselectivity.Various P-ylides including ester-,ketone-and amide-style P-ylides were all applicable.This asymmetric reaction occurs through the cleavage of two bridgehead C-O bonds and the formation of two C-C bonds to provide enantioenriched benzonorcaradienes bearing three contiguous stereocenters.Chapter 3: Rhodium-catalyzed asymmetric ring opening/cyclization of oxabenzonorbornadienes with 1-styrylnaphthols was first achieved to synthesize tetra-substituted tetrahydrofuran derivatives,providing a new possibility for the synthesis of polysubstituted tetrahydrofuran skeletons.