Research On The Synthesis Process Of Two OLED Materials With DPHA Structure

Organic light-emitting diode(OLED)has unique capability of dynamic display and full contrast.What’s more important is that it is thin and flexible,which meets the requirements of various communication equipment and displays expected in the future.Anthracene is a star blue light molecule in OLED.It is often used as the basic skeleton structure of fluorescent molecules.However,the unmodified anthracene molecule has low fluorescence quantum efficiency and poor film-forming performance.Therefore,almost all anthracene molecules will be modified by other functional groups to improve its performance.DPHA is an excellent luminescent material when benzene ring is introduced into anthracene molecule at position 9 and 10.11,11-dimethyl-3-(2-(10-pheny-lanthracen-9-yl)phenyl)-11H-benzo[b]fluorene(DPHA-F)was prep-ared by modifying DPHA with 11,11-dimethylbenzofluorene;1,6-bis(3-(10-phenylanth-racen-9-yl)phenyl)-1,5-dihydropyrene(DPHA-P-DPHA)can be obtained by modifying dpha with pyrene.Through literature consult,it is found that there are some reports on the synthesis of these two structures,but the laboratory is needed more stringent conditions,and the yield is lower.In order to overcome the shortcomings of the existing methods,a feasible and economical synthetic route was selected,and each step of the reaction was optimized by response surface method,which laid a foundation for the pilot production of these two materials.In this paper,the synthesis of DPHA-F,DPHA-P-DPHA and its intermediate DPHA boric acid were studied:(1)For the intermediate DPHA boric acid,the only reported synthesis route was investigated.It was found that there was one step which was difficult to realize.Therefore,the route was optimized from 5 steps to 4 steps based on the actual experiment.The reaction was studied by single factor and response surface methodology.Finally,9-Bromoanthracene,Suzuki Miyaura and substitution reactions were selected to obtain dpha boric acid.The results showed that the reaction time,temperature and catalyst had obvious effects on the yield of DPHA boric acid.The total yield was57.22%,which was higher than 49.86%reported in the literature.(2)For two target compounds DPHA-F and DPHA-P-DPHA,the reaction solvent,monomer dosage,reaction time and temperature were determined by single factor method,and their yields were optimized by response surface methodology.The total yields were 50.74%and 44.37%respectively,and the purity of the products was more than 99%.Compared with the reported route,this route has the advantages of short reaction period,simple operation,low cost and high efficiency.(3)The structures of DPHA-F,DPHA-P-DPHA,DPHA boric acid and their intermediates were confirmed by ~1H NMR and MS,and their structures were determined by DSC-TGA and UV fluorescence spectra.The decomposition temperatures of DPHA boric acid,DPHA-F and DPHA-P-DPHA were 146℃,337℃and 320℃,respectively.The strongest fluorescence emission wavelengths were at 454nm,450nm and 489nm,respectively.