Nickel-Catalyzed Electrophilic Asymmetric Arylalkylation And Arylacylation Of Alkenes

In the synthesis of natural products and pharmaceuticals,difunctionalizations of alkenes provide convenient and effective ways to construct complex molecules.In recent years,organic chemists have developed a series of difunctionalizations of alkenes through redox-neutral strategy,oxidative cross-nucleophile strategy and reductive cross-electrophile strategy.However,prior to our work,asymmetric difunctionalization of the alkenes via reductive cross-electrophile strategy has not been reported.Thus it is of enormous interest to develop this type of reaction.This dissertation is divided into three chapters.Chapter 1:Development of transition metal-catalyzed dicarbofuntionalizations of alkenes.Dicarbofuntionalizations of alkenes via transition metal catalysis is a direct and efficient method for introducing two different carbon moieties across a carbon-carbon double bond.In this section,we have reviewed the progress in this area in recent years.Among these reactions,redox-neutral strategy finds the most applications,wherein numerous two-component and three-component reactions have been developed,most of which are racemic versions with a few exceptions of asymmetric variants.In addition,rapid progress has been achieved in oxidative cross-nucleophile strategy in recent years.However,this strategy suffers from substrate scope limitation and difficulty to achieve asymmetric induction.In comparison to the two strategies aforementioned,reductive cross-electrophile variant merits the virtues of high step-economy and functional group tolerance via avoidance of the use of pregenerated organometallics.Chapter 2:Nickel-catalyzed reductive electrophilic asymmetric aryl-alkylation of unactivated alkenes.Herein,we accomplished two-component asymmetric aryl-alkylation reaction of unactivated alkenes via a reductive cross-electrophile strategy under the catalysis of a chiral nickel complex,wherein alkyl halides or NHP esters are employed as the alkyl source.By using this method,we synthesized a series of benzene-fused cyclic compounds containing a quaternary stereocenter.Chapter 3:Nickel-catalyzed reductive electrophilic asymmetric aryl-acylation of unactivated alkenes.Carbonyl is a ubiquitous functional group in pharmaceuticals and natural products.On the basis of our previous work,we successfully applied the cross-electrophile strategy in the asymmetric two-component aryl-acylation of unactivated alkenes.In this method,2-pyridiny esters and isocyanates are utilized as the acylating agents under the catalysis of a chiral nickel complex,providing a novel entry to synthesize chiral ketones and amides bearing a quaternary stereocenter.