In 2019,ACS Omega included an article by Chen, Zhicai; Li, Huanhuan; Tao, Ye; Chen, Lingfeng; Chen, Cailin; Jiang, He; Xu, Shen; Zhou, Xinhui; Chen, Runfeng; Huang, Wei. Electric Literature of C5H3Br2N. The article was titled 《Tuning Intramolecular Conformation and Packing Mode of Host Materials through Noncovalent Interactions for High-Efficiency Blue Electrophosphorescence》. The information in the text is summarized as follows:
Mol. conformation plays an important role in tuning the packing modes of organic optoelectronic materials to achieve enhanced and/or balanced charge transport. Here, we introduce the noncovalent intramol. interactions to the host materials of phosphorescent organic light-emitting diodes (PhOLEDs). Different numbers and/or positions of intramol. CH···N noncovalent interactions were constructed by using different N-heterocycles of pyridine, pyrimidine, and pyrazine as acceptor units and carbazole as the donor unit in a donor-acceptor-donor (D-A-D) motif. Thus, designed D-A-D mols. were synthesized facilely through a one-step Ullmann reaction in high yields, showing varied intramol. interactions to regulate the mol. conformation significantly. Impressively, owing to the quasi-parallel mol. conformation, which is beneficial for forming facile transporting channels of both holes and electrons, the newly designed host material of 9,9′-(pyridine-2,5-diyl)bis(9H-carbazole) exhibits good device performance of blue PhOLEDs with current, power, and external quantum efficiencies up to 33.0 cd A-1, 32.1 lm W-1, and 16.3%, resp. This work highlights the significant importance of the noncovalent interactions in designing advanced organic semiconductors for high-performance optoelectronic devices. After reading the article, we found that the author used 2,5-Dibromopyridine(cas: 624-28-2Electric Literature of C5H3Br2N)
2,5-Dibromopyridine(cas: 624-28-2) belongs to pyridine. Pyridine is very deactivated towards electrophilic substitution with respect to benzene. For this reason classical formylation, using methods such as the Gattermann or Vilsmeier reactions, are not generally successful. Electric Literature of C5H3Br2N