Study On The Intramolecular Asymmetric C-H Insertion Reaction Based On Enynones As Carbene Precursors

Due to its abundant reaction characteristics,metal carbene has attracted widely attention by synthetic chemists.In recent years,metal carbene,which is generated by transition-metalcatalyzed via enynones,is getting more and more attention.Compared to traditional diazo compouds as precursors of metal carbene,enynones as precuesors of metal carbene has the following advantages.1.no risk of explosion;2.low toxicity;3.the reaction can be carried out in a one-pot process without slow addition;4.no nitrogen elimination;5.the metal carbene generated by enynones unually has a slower rate of self-dimerization;6.the carbene produced via enynones is donor-/donor-donor carbene,it is safer than the strategy by diazo compouds as precursors.In the background of the study on the production of oxyenium based on acetylcarbonyl compounds,our group studied the reaction of intramolecular asymmetric carbene-transfer under transition metal catalyzed with enynones as carbene precusors.This thesis is divided into the following parts.The first chapter briefly outlines the metal carbene and the precursors which are often used to generate metal carbene.Then,some chemical reactions of enynones as precursors of metal carbene are introduced,which leads to the specific research contents of this paper.In the second chapter,we mainly studied the use of enynone as precursors of metal carbene and under the catalysis of chiral carboxylic acid rhodium dimer,for the first time realized the intramolecular C-H insertion and cyclopropanation by the non-diazo strategy to produce donor-/donor-donor carbene.The reaction condition was simple and mild and has wide substrate scope,furthermore,it can be highly efficient synthesis of a series of chiral indoline,dihydrobenzofuran,tetrahydrofuran and tetrahydropyrrole derivatives.Among the product of this reaction,the diastereoselectivity could be greater than 99:1 and the enantioselectivity could be up to 99%.The resulting C-H insertion product could be further derivatized,and the derivatives’ enantioselectivity could be well maintained.In the end,the above method provided a new way to produce donor-/donor-donor carbene.