Construction Of Nitrogen-containing Heterocycles Through Oxidative Coupling-cyclization Cascade

The synthesis and bioassessment of diverse N-heterocycles have attracted a lot of attention in recent decades as a result of the enormous advancements in medicinal chemistry.Hence,one ongoing research area for organic chemists is the development of new techniques for the effective synthesis of nitrogen heterocyclic molecules.Cascade reactions,which are among the many synthetic transformations,are regarded as potent methods for the synthesis of heterocyclic compounds because they enable the direct synthesis of complex molecules from readily accessible starting materials under the same conditions and all at once.Due to their capacity to accelerate reaction times,minimize waste,and improve reaction conditions,transition metalcatalyzed cascade reactions in particular have grown in popularity as a research area in recent years.In this research,a three-step process to prepare various nitrogen-containing heterocycles is described.For the effective synthesis of heterocycles containing nitrogen,a new technique is presented.The study of heterocycles containing nitrogen is organized into three main sections in this thesis:(1)In the first chapter,a copper-catalyzed cascade cyclization reaction enabling one-pot synthesis of acridine compounds was reported.By using copper nitrate trihydrate as a catalyst and hydrochloric acid as an additive in an air-conditioned environment at 100 ℃ for 12 hours,we have created a straightforward and straightforward process from arylboronic acids and anthranil as starting materials to achieve a simple and effective amination/cyclization to obtain acridine compounds.This one-pot reaction offers a straightforward method to create the acridine skeleton because to its straightforward operation,lack of precious metal requirements,and strong functional group compatibility.This is a helpful addition to the current synthetic techniques.(2)In the second chapter,the quinoline skeleton was created via a copper-catalyzed cascade cyclization procedure.Using isopropenyl boronic acid pinacol ester and substituted anthranil as starting materials,copper acetate as catalyst,magnesium sulfate as additive,in MeOH: TFE(1:1)mixed solvent,in argon atmosphere at 100 ℃,reaction for 48 hours,and successfully obtained multi-substituted quinoline compounds.A new method for the synthesis of polysubstituted quinoline compounds is shown by the straightforward reaction that produced a number of quinoline compounds in high yield.(3)The third chapter describes the creation of an intramolecular acceptorless oxidative dehydrogenation coupling process using clean,green visible light energy.Using tetrabutylammonium bromide as a catalyst and 2-(benzylamino)benzamide under visible light irradiation,different quinazolinone compounds were produced in good yields without the use of any extra additions.This research significantly advances the field of newly discovered green oxidation systems and advances the field of green chemistry.