Functionalized Quinazolines and Pyrimidines for Optoelectronic Materials

Abstract

Background: Quinazolines, the important group of benzodiazines, are widely known in medicinal chemistry due to their broad spectrum of biological activities. Notably, extensive research on the synthesis and application of quinazoline derivatives for electronic devices, luminescent elements, photoelectric conversion elements, and image sensors has been published recently. Objective: This review reports luminescent small molecules and chelate compounds including a quinazoline or pyrimidine ring in their scaffold highlighting their applications related to photo- and electroluminescence. Conclusion: It is clear from the review of the topic that the incorporation of quinazoline and pyrimidine fragments into π-extended conjugated systems is of great value for the creation of novel optoelectronic materials. Polyhalogen derivatives represent the major starting materials for polysubstituted fluorescent quinazolines. Electroluminescent properties of aryl(hetaryl)substituted quinazolines with π-extended conjugated systems proved to be the most important. Incorporation of benzimidazole, carbazole, triphenylene or triphenylamine fragments into quinazoline scaffold allows fabricating materials for organic light-emitting diodes, including white OLEDs and highly efficient red phosphorescent organic light-emitting diodes. Moreover, arylvinylsubstituted quinazolines are of great interest as potential structures for nonlinear optical materials and for colorimetric pH sensors. Iridium complexes based on 2-aryl(thienyl) quinazoline or pyrimidine derivatives represent high-efficiency phosphorescent materials for OLEDs. Pyrimidine push-pull systems are of considerable importance as potential photosensitizers for dye-sensitized solar cells. Pyrimidine derivatives bearing phenylacridine or phenylphenoxazine fragments at the positions 4 and 6 are capable to function as thermally activated delayed fluorescence emitters.

The effect of protonation on the excited state dynamics of pyrimidine chromophores

“…These heterocycles constitute electron accepting groups in D-π-A structures which result in efficient Intramolecular Charge Transfer (ICT) and are potential candidates for application in optoelectronics, sensors and non-linear optics. [38][39][40][41][42][43][44][45][46][47][48][49] Protonation strengthens their electron accepting ability, enhancing the ICT.…”

Study of methylation reactions of 2-phenylquinazoline-4-tion with “soft” and “hard” methylation agents and determination of its biological activity

“…Rf-values were determined on plates "Silyfol" UV-254 (ChSSR), Disclosure: iodine vapors. Solvents (ethanol, acetonitrile, dioxane-1.4, dimethylformamide) were purified and absolute according to the standard method [7,[9][10]…”

“…It allows to find compounds with different properties among the synthesized substances and to use them successfully in various sectors of the economy, including medicine, agriculture, food and light industry and other fields. 5-Methyluracil is widely used in medicine as a biologically active compound found in cancer, as well as among heterocyclic compounds, and has been successfully used as a pesticide herbicide, fungicide, insecticide, attractant, repellent, and plant-repellent [4,[6][7]. The number of chemicals has now reached 13 million in the period of the continuous development of organic chemistry and rising to the supramolecular level.…”

Effect of protonation on the photophysical properties of 4-substituted and 4,7-disubstituted quinazoline push-pull chromophores

“…During the past decade there has been great interest in the design of push-pull azaheterocyclic chromophores due to their high tunability and the sensitivity of their photophysical properties to the environment. [1][2][3][4][5] In these structures, the nitrogen heterocycles are generally used as the electron-withdrawing part. These compounds exhibit intense positive emission solvatochromism, which is characteristic of compounds that undergo an intramolecular charge transfer (ICT) upon excitation.…”