Construction Of The Quinoxaline With New Carbon Source Reagents And Arylanilines Via[5+1] Cyclization Reaction

Quinoxaline derivatives have important research significance in the synthesis of functionalized drug molecules and applied materials.In recent years,developing efficient synthetic methods or novel carbon source reagents to construct quinoxaline molecular skeletons have gradually become a research hotspot.However,at the current stage,there are many synthesis strategies still require the intervention of various catalysts and additives,or relatively harsh reaction conditions before proceeding.Therefore,the design of many efficient and environmentally friendly catalytic systems,and the development of novel carbon source reagents that can be used to construct quinoxaline derivatives,this still have great research prospects and extremely important research significance.In this thesis,based on a large amount of experimental research,we developed two novel carbon source reagents were used for the construction of quinoxaline molecules,as well as efficient and simple reaction systems.Simultaneously,in order to further enrich the synthetic strategies of quinoxaline derivatives,which provides a certainly theoretical reference significance for the effective synthesis of quinoxaline derivatives.The main contents are as follows:Firstly,the tertiary amine of containing α-H(triethylamine)was choosed as a new carbon source reagent that be used for the construction of nitrogen-containing quinoxaline heterocycles.A reaction system for dehydrogenation or hydrogen transfer of high-valent state ruthenium trichloride(RuCl3)for the cleavage of the C-N bond was designed.At the same time,aromatic amine substrates of different substituents and different types amines of containing a-H in this system were investigated.The most noteworthy aspect is that the direct C-NO2 cleavage of nitroalkanes and nitroaromatic hydrocarbons of containing α-H was firstly discovered via RuCl3 catalyzed involving cyclization.In addition,the synthesis of an antileishmanian drug was achieved with excellent yields under this transformation.The OLEDs material can also be synthesized through chemical coupling methods based on quinoxaline derivatives,the photoelectric properties and DFT theoretical calculations of this OLEDs molecule were discussed tentatively.Secondly,we designed an efficient assembly strategy for constructing quinoxaline structures via HFIP-promoted the cleavage of difluorocarbene reagents to give C1 synthons.Based on the[5+1]cyclization reaction of acidpromoted difluorocarbene C-N bond cleavage effectively avoids the problem of excessive consumption of precious metals or excessive use of oxidants.Moreover,this synthesis strategy exhibits good substrate range and group tolerance.Besides,in the subsequent large-scale synthesis stage,the obvious advantages of this reaction system was further illustrated by recycling and applying for the solvent,this efficient and environmentally friendly design strategy is expected to achieve the synthesis of OLEDs monomeric molecules,which has great research significance in both theoretical design and synthetic applications.