Synthesis And Research Of 9, 10-Dimethyl-9, 10-Ethanoanthracene-Based Diazoles And Quinoxalines

As a class of organic molecules rich in carbon atoms and possessing large π-conjugated systems,the structural properties of polycyclic aromatic hydrocarbons(PAHs)lead to their potential applications in the fields of organic optoelectronic materials such as organic light-emitting diodes,organic field-effect transistors,and organic photovoltaic cells.The application value of polycyclic aromatic hydrocarbons is one of the hot spots in the field of materials chemistry.One of the most common methods to improve the performance of organic electronic devices is to dope polycyclic aromatic hydrocarbons with elements such as nitrogen and sulfur.In this paper,9,10-dimethyl-9,10-ethanoanthracene,which is a rigid anthracene linked by an ethylene bridge,is used as the core.The synthesis of fused heterocycles(quinoxalines and diazoles)from 9,10-dimethyl-9,10-ethanoanthracene and their properties have shown that these compounds have potential applications in the fields of organic optoelectronic materials and supramolecular chemistry.The first part of this paper designed and synthesized a series of quinoxaline and diazole derivatives based on 2,3,6,7-tetraamino-9,10-dimethyl-9,10-ethanoanthracene and Their properties were studied.Our synthesis started with the scalable reaction of2,5-hexanedione with phenylmagnesium bromide in THF,which formed the 2,5-diphenylhexane-2,5-diol.The subsequent ring-closure by the Friedel-Crafts alkylation in the presence of aluminum chloride afforded 9,10-dimethyl-9,10-ethanoanthracene.It was subsequently brominated with liquid bromine in 1,2-dichloroethane to form2,3,6,7-tetrabromo-9,10-dimethyl-9,10-ethanoanthracene.Then the utilization of multi-fold amination synthetic strategy between benzophenone imine and 2,3,6,7-tetrabromo-9,10-dimethyl-9,10-ethanoanthracene furnished the formation of 2,3,6,7-tetraamino-9,10-dimethyl-9,10-ethanoanthracene.This amine salt reacts with diketone compounds in potassium acetate and acetic acid system to obtain quinoxaline derivatives;Tetrahydrochloride reacts with selenium dioxide at room temperature to obtain selenodiazole derivatives,and reacts with thionyl chloride under mild conditions to obtain thiadiazole derivatives.This series of quinoxaline and oxadiazole compounds were tested with the relevant ultraviolet absorption spectrum and fluorescence emission spectrum,and the results showed that when the quinoxaline derivatives were introduced into aromatic heterocyclic functional groups under the same test conditions,the fluorescence intensity would increase.When the aromatic ring has different substituents,the UV absorption and fluorescence intensity of the target product will change accordingly.For diazole compounds,under the same test concentration,the introduction of sulfur element compared with selenium element,the fluorescence intensity will be stronger,and the ultraviolet absorption will also change accordingly.The second part of this paper mainly completed the synthesis and properties of quinoxaline derivatives based on 2,3,6,7-tetrabromo-9,10-dimethyl-9,10-ethanoanthracene.On the basis of the first part of the paper,2,3,6,7-tetrabromo-9,10-dimethyl-9,10-ethanoanthracene and diamines were coupled under the catalysis of Ru Phos Pd G2 to obtain the imine product.The target product quinoxaline derivatives can be obtained by oxidation in acetic acid and potassium acid system.The UV and fluorescence tests on them at the same time show that when the conjugated system is extended,the fluorescence intensity is stronger,and the UV will also produce a corresponding red-shift phenomenon.Therefore,such quinoxaline derivatives can also be identified as potential organic light-emitting materials.