Studies On Copper-Catalyzed Esterification Of N-Heteroaryl Methanes With Acids By Oxidative Dehydrogenation

N-heteroaryl esters are widely used in biomedicine,natural products chemistry and fine chemicals such as cosmetics,flavors and fragrances,food additi ves because of their special physicochemical properties.At present,it ha d been reported that many methods for synthesizing N-heteroaryl esters have disadvantages such as expensive catalysts,pre-activation of substrates,and poor compatibility of functio nal groups.and poor compatibility of functional groups.In this dissertation,we realized the copper catalyzed dehydrogenative-cross-coupling esterification of methyl group sp~3C-H bond(s)with O-H bond of acids.This catalytic transformation promoted N-heteroaryl esters synthesis chemistry utilizing the readily available N-heteroaryl methane derivatives with simple and cheap acid compounds,which presented high atomic utilization and good economy properties.This dissertation mainly concerns about the facile activation of mono(dual)sp~3C-H bond(s)to methyl group o f N-heteroarylmethans,coupled with acids.The detailed research contents and results are summarized as follows:1.Copper-catalyzed cross-dehydrogenative mono-esterification of readily available N-heteroarylmethanes with acidsCopper-catalyzed cross-dehydrogenative mono-esterification of readily available N-heteroaryl methanes with acids has been realized in good yields of target products.The catalytic transformation shows good functional group t olerance and wide scope of substrates,of which involving aromatic acid and aliphatic acid such as cyclic acids and chain acids exhibiting certain reaction properties,and the highest yield up to 98%.The reaction system presents high efficiency,good atomic economy and simple operation.The reaction can be scaled up to the gram scale(100 mmol),providing new methods and new ideas for the synthesis of drug molecules and natural products;2.Copper-catalyzed cross-dehydrogenative di-esterification of readily available N-heteroaryl methanes with acidsCopper-catalyzed cross-dehydrogenative di-esterification of readily available N-heteroaryl methanes with acids has been realized in good yields of target products.Through simple regulation of acid loading,it is possible to achieve di-esterification of the methyl group with high chemoselectivity,and the highest yield up to 78%.The protocol is suitable for a high chemical selectivity and exhibits high step efficiency and atom economy.It is envisaged that this r adical-promoted one-pot dual functionalization of C(sp~3)-H bond is a general and facile strategy that would enrich the applications of N-heteroaryl methanes.