Synthesis Research Of Benzothiazine And Epoxy Ethane Derivatives Catalyzed By Tertiary Amine

Heterocyclic compounds are these carbocyclic compounds in whichone or more carbon atom are substituted by O、S、N、Se、P、As、Sb andother non-carbon atoms. Heterocyclic compounds have a wide range ofapplications in molecular biology, organic chemistry, pharmaceuticalchemistry, dye chemistry, pesticide chemistry and so on. Therefore, thestudy of heterocyclic compounds has attracted more and more people’sattention, and has become one of the active research field. Protectingenvironment is an eternal pursuit, and chemical workers engaging inscientific research work have always paid attention to this pursuit. In orderto find recycling, environmental friendly catalyst, scientists developorganocatalysts. We know organocatalysts have the advantages of simpleoperation, environmental friendliness, mimic enzyme catalysischaracteristics, and they also have the advantages of simple structure, stableperformance, less expenses. Organocatalysts have attracted more attention inrecent years. This thesis draw out from the two aspects above. We mainlystudied multicomponent reaction catalyzed by DABCO （1,4-diazabicyclo[2.2.2]octane） and synthesized benzothiazine derivatives. Secondly, wesynthesized α, β-epoxy ketone derivatives catalyzed by triethylamine.Specific work is as follows:Initially, DABCO catalyzed one-pot, three-component reaction for thesynthesis of3,4-dihydro-2H-1,4-benzo[b]thiazines with good to excellentyields from easily available2-aminobenzenethiol, aromatic aldehydes andα-bromo ketones. The operation of the experiment was convenient, and theproducts can be easily separated. Then, we choosed DABCO as catalyst to synthesize α, β-epoxy ketone derivatives from aromatic aldehydes and2-bromo-1-phenylethanones. The optimization of the reaction conditionswere found to be20mol%catalyst of triethylamine, with H₂O as the solventin the presence of K₂CO₃at room temperature for6h. The yield reached95%and higher.