Studies On The Multicomponent Synthesis Of Nitrogen-containing Heterocycles

The nitrogen-containing heterocyclic compounds with a range of physiological and pharmacological activities widely exist in natural products. They have been widely used not only in medicine, herbicides, but also in dye, multifunctional materials and many other areas. And multicomponent reactions(MCRs) have gained quite popularity in the field of organic synthesis and pharmaceutical chemistry on account of its high atom economy, convergence, excellent yield and easy execution. In this dissertation, a series of nitrogen-containing derivatives has been synthesized by MCRs and the structures of all compounds have been characterized. The research includes four parts as follows:In part one, the progress of the constructions of nitrogen-containing heterocycles by MCRs in recent years has been briefly introduced.In part two, an efficient and stereoselective synthetic procedure for highly functionalized tetrahydroacenaphtho[1,2-b]indolone derivatives has been successfully developed by the three-component reaction of acenaphthequinone, enaminones and barbituric acid in the presence of a catalytic amount of L-proline. We also studied the reusable efficiency of the catalyst. This method has the advantages of readily available starting materials, mild reaction conditions and operational simplicity. The structures of all products were characterized by IR, 1H NMR, 13 C NMR and HRMS. The structures of the product 4d was further comfirmed by single crystal X-ray diffraction analysis.In part three, the development of the synthesis for 3-aminopyrazolone derivatives and chromeno[3,4-c]pyridin derivatives via the multicomponent reaction of malononitrile、ethyl cyanoacetate、hydrazine hydrate and aldehyde(or salicylaldehyde) in ethanol is described. It has a series of features including convenient operations, environmental friendliness and short reaction time. The structures of all products were characterized by IR, 1H NMR, 13 C NMR and HRMS. The structure of the product 11 c was further comfirmed by single crystal X-ray diffraction analysis.In part four, a series of chromeno[4,3-b]pyridin derivatives has been synthesized via the multicomponent reaction of 4-oxe-4H-chromene-3-carbaldehyde, ethyl cyanoacetate(or malononitrile) and aromatic amines efficiently with the mixture of ethanol and water(ethanol: water= 3:1) as solvent. This protocol has the advantages of convient operation, excellent yields, environmental friendliness and wide substract diversity. The structures of all products were characterized by IR, 1H NMR, 13 C NMR and HRMS. The structure of the product 14 e was further comfirmed by single crystal X-ray diffraction analysis.