Synthesis Of Five-membered Nitrogen Heterocyclic Compounds Via Cucatalyzed [3+2] Cyclic Oxidation

Nitrogen-containing heterocyclic compounds are important components of organic compounds and are widely present in many natural products.Among them,pyrrole and pyrazole compounds are an important class of fine chemical intermediates.Due to their special structure and good biological activity,they can be used not only in medicine,pesticides and dyes,but also in the synthesis of some photovoltaic materials.Important role.Due to its broad prospects and great application value,research on pyrrole and pyrazole compounds has become a hot topic,and novel synthetic methods have been reported continuously.Based on this background,the subject during graduate school was: copper-catalyzed [3+2] cyclic oxidation of five-membered nitrogen heterocyclic compounds.In this thesis,a total of 70 fused heterocyclic target compounds of three major classes were synthesized through efficient and novel cyclization oxidation processes using catalytic amounts of catalysts,of which 46 were new compounds.The main research contents are as follows:1.A series of multi-component synthesis of phenylindole with 1,3-dipolar cycloaddition and oxidation reaction was carried out with pyridine,benzyl bromide and chalcone as the raw materials and promoted by catalytic amount of copper acetate Phenylketones.By exploring and optimizing the reaction conditions,the conditions of catalyst,solvent,temperature,reactant feed ratio and feed order were screened,and the best reaction conditions were obtained: potassium carbonate as base,0.25 equivalent copper acetate as catalyst,and DMF As a solvent,the reaction temperature was 120 ?.Under the protection of oxygen,33 phenylindolophenone compounds were synthesized in a yield of 44?89%,of which 28 were new compounds.The method is simple in operation,does not need to separate intermediate products,and is efficient and cheap.2.A series of middle nitrogen indene compounds were synthesized by pyridine,benzyl bromide and 1,4-naphthoquinone as raw materials and catalyzed by copper chloride in a one-pot multi-component reaction.After exploring and optimizing a series of experimental conditions,the effects of the conditions such as solvent,temperature,additives,feeding order,and the ratio of the reaction substrate were investigated.The optimal conditions for the reaction were: cesium carbonate as the base and DMF as Solvent,at a temperature of 110 ?,0.5 equivalent of copper chloride catalyzed the reaction for 4 h,and 17 middle indene compounds were synthesized in a yield of55?85%,6 of which were new compounds.3.Benzene hydrazine and 2-cyclohexen-1-one were studied as raw materials.A series of 1,3-diamines were synthesized by nucleophilic addition,cyclization and oxidation under the catalysis of copper chloride.Phenyltetrahydroindoles.The investigation optimized the reaction conditions,and screened the catalyst,temperature,solvent,additives and reactant ratios.The optimal reaction conditions were: copper chloride as the catalyst,potassium carbonate as the base,and the reaction temperature was 50 ?.After reacting in tetrahydrofuran for 8 h,21 1,3-diphenyltetrahydroindole compounds were synthesized in a yield of 55?90%,of which 12 were new compounds.