CH-activated Tandem Reactions Involving Alcohols

Alcohols are abundant,cheap and easy to obtain,and are ideal synthons.In recent years,transition-metal catalyzed C–H activation/tandem reactions involving alcohols have been widely used in the synthesis of pharmaceuticals,pesticides,natural products and new materials,and have also gradually become an important synthetic tool in modern organic chemistry.In this thesis,a series of nitrogen-and oxygen-containing heterocyclic compounds have been synthesized efficiently with high selectivity using alcohols as substrates and transition metals as catalysts through a C–H activation/cyclization strategy.This thesis is divided into three chapters as follows:(1)In chapter 1,we summarized the recent development of transition-metal catalyzed C–H activation reactions using alcohols as substrates,highlighting the C–H activation reactions involving allyl alcohol,cyclopropanol,propargyl alcohol and other simple alcohols,and clarifying the subject matter of this thesis.(2)In chapter 2,an efficient Rh(III)-catalyzed oxidative annulation of isoquinolinone with allyl alcohol has been developed.This tandem reaction utilized allyl alcohol as C1 synthons,copper salts and air as oxidants,and sodium acetate as base additives to efficiently and selectively construct a series of potentially biologically active isoindolo[2,1-b]isoquinolin-5(7H)-one derivatives.The cascade reaction features simple operation,readily available starting materials,high atom economy and good functional group tolerance.In addition,we have found that isoquinolinone can be in situ generated by cyclization of alkyne from readily available N-methoxybenzamides via Rh(III)catalyst,which then proceed oxidative annulation with allyl alcohol.The practicality of this methodology was further demonstrated by achieving one-pot reaction of isoindo[2,1-b]isoquinolin-5(7H)-one.(3)In Chapter 3,we have developed a one-pot three-component tandem cyclization reaction using salicylaldehyde,cyclopropanol and alkyl alcohols to construct a series of benzofuran-3(2H)-ones with quaternary carbon centers via Rh(III)-catalyzed C–H/C–C bond activation and tandem cyclization reactions.This reaction has the advantages of a wide range of substrates,high atomic economy and simple initial raw materials,and provides a novel route for the synthesis of benzofuran-3(2H)-one derivatives.In terms of the study of the reaction mechanism,we have proposed two possible reaction courses through extensive controlled experiments and reported literature.