New Method Synthesis Push-pull3,4-Diaryl-Substituted Maleimide And The Design And Synthesis Of Its Probe

In this paper，Bromophenyl acetonitrile and ethyl chloroformylformate were used as rawmaterials, we explore a new method for the synthesis of diphenyl maleimide. Design andsynthesize a fluorescent probe that diphenyl maleimide were used as the light-emittingsubstrate.In recent year, as the light-emitting part of the fluorescent dye molecules, diphenylmaleimide has attracted a growing number of reseacher’s interesting. Its character andsynthesis method has been made plenty of reseach. In this paper, we briefly introduces theprinciple of fluorescent molecules, the relation between structure and character, severalinfluencing factors, principles of fluorescent probes’ design and the development offluorescent probes in recent years.1. Based on this, Some rasearchs of the synthesis method were made, we discover twosafer, milder, simpler isolate synthesis method. It may be used for mass production.Road1: In the condition of AlCl3/CH2Cl2, bromobenzene and Ethylchloroformylformate be connected by acylation reaction, then hydrolyzed by NaOH solution,and acidize by HCl solution, at last, the keto acid be reflux in KOH solution to get its formate.On the other hand, bromophenyl acetonitrile be hydrolysis by NaOH solution, and acidizedby HCl solution, then closing ring with ketone formate in the exist of acetic anhydride to getthe maleic anhydride. Reflux the maleic anhydride in HMDS/MeCN/MeOH condition can getthe diphenyl maleimide.Road2: The same as road1, bromobenzene and Ethyl chloroformylformate be connectedby acylation reaction. Bromophenyl acetonitrile be reflux in the AlCl3/CH2Cl2condition andthen converted to bromobenzene acetamide. While bromobenzene acetamide and keto ester bereflux in the exist of anhydride under100℃to get the diphenyl maleimide product.2. According to the principle of emitting of push-pull system fluorescent molecules, Themolecular were modified to make its characteristic spectrum more aproach the visiable red region that we wanted. We synthesis red molecule named3,4-bis (4-(diphenylamino) phenyl)-1-methyl-1H-pyrrole-2,5–dione. Its conjugated system and the push-electronic effect allbe increased and it is an excellent molecule as fluorescent materials and the non-doped redemitting materials.3. We get a single crystal of compound2-14. We can see from the X-ray single crystaldiffraction patterns that the structure of the molecule is not a planar as we imagined. Instead,the three plane all form certain angle between each other, this reduce the conjugate propertiesand electronic conductivity of the molecules. That is the reason why the fluorescence intensityweaken and the color change.