Remote Hydroarylation Of Alkenes Using Borate As An Orientating Group And The Preliminary Investigation Of The Asymmetric Version

Remote functionalization is defined as functionalization at an unactive site,which is remote from the initial functional group.Transition-metal-catalyzed remote functionalization of alkenes is initiated from the original C=C double bond while selectively functionalized at a distal position/In contrast,traditional cross-coupling reaction only happened at the original site.Remote functionalization is generally realized by alkene isomerization(also known as chain walking or metal walking)and sequential functionalization.It offers a new strategy for the selective functionalization of remote inert sp3 C-H bonds.More importantly,isomeric mixtures of olefins can be transformed into the value-added products in a regioconvergent way.Remote functionalization,especially initiated by the abundant nickel catalyst,has received great attention during the last few years.Benzylic borates are important and versatile building blocks in organic synthesis,natural products,medicines,materials,etc.Especially,chiral benzylic borate moieties can be transformed into a series of functional groups while retaining the original sterocenters.In this thesis,we mainly focus on NiH-catalyzed remote hydroarylation of alkenes with a borate at the distal position along the alkyl chain.We also explored the asymmetric transformation while using chiral ligands.The proposed reaction mechanism is through NiH catalyzed iterative migration insertion and ?-H elimination,generating the most reactive alkylnickel species at a position of borate for arylation to produce the final benzylic borate.The charter 1 is the background of metal-hydride-catalyzed remote functionalization of alkenes and the synthesis and transformation of benzylic borate.In charter 2,we presented our work on NiH-catalyzed remote hydroarylation of alkenes linking a borate group.Under mild conditions,a broad scope of both alkenes and aryl halides is found to be suitable for this transformation.In charter 3,we reported our preliminary investigation on the asymmetric remote hydroarylation of vinyl-boronic acid pinacol cyclic ester derivative based on the result of charter 2.