The New Reaction Of ?-methyl Ketone Pyridine Ylide As The Synthetic Blocks In The Construction Of Heterocyclic Compounds

Heterocyclic compounds are a class of the important physiologically active molecule structure which widely exists in nature in the living body.Human currently used drugs,the majority contained heterocyclic skeleton.Therefore,the study to synthesize heterocyclic compounds has always attracted much attention of chemists.As extensive and convenient readily available chemicals,a-methyl ketone pyridine ylide has widespread chemical properties,which not only can participate in nucleophilic addition/substitution,?-migration rearrangement,Michael addition and 1,3-dipolar cycloaddition reaction.It but also have became a hot topic using ?-methyl ketone pyridine ylide as synthesis blocks to synthesize heterocyclic compounds.In this paper,we utilised pharmacological active heterocyclic compounds as a basic skeleton,which mainly studied the 2-hydroxy-2,3-dihydrofuran and 2,3-substituted indole compounds synthesis strategies and discussed their reaction mechanism.Subsequently,2-hydroxy-2,3-dihydrofuran compounds were used to further synthesize potential biological activie 4-(1H-pyrazol-4-yl)pyridazine derivatives.The main content is as follows:The chapter 1,we summarized ?-methyl ketone pyridine ylide as synthesis blocks to synthesize heterocyclic compounds and the synthesis of 2-hydroxy-2,3-dihydrofuran in recent years.In view of this,we proposed the research topic of this thesis.The chapter 2,based on our previous study to the 2-ene-1,4-diones and the awareness of the 2-hydroxy-2,3-dihydro-furan compounds,we studied the promotion of K2CO3 to efficient synthesize the 2-hydroxy-2,3-dihydrofuran compounds from a-methyl ketone pyridine ylide and 2-ene-1,4-diones.Through a series of experiments and supporting literature,we propose a possible reaction mechanism via Michael addition/intramolecular cyclization/elimination a self-sorting property during the reaction process.In order to verify the reaction practical value,we use 2-hydroxy-2,3-dihydrofuran compound reacted with hydrazine hydrate in ethanol to obtain 4-(1H-pyrazol-4-yl)pyridazine derivatives.The chapter 3,based on having excellent pharmacological active 2,3-substituted indole compounds.We used Cs2CO3 as base to one-pot directly synthesize 2,3-disubstituted indoles from 2-aminobenzaldehyde/2-amino aryl ketones,tosylhydrazine,and aromatic aldehydes via sequential condensation,nucleophilic addition,elimination,and intramolecular cyclization.