Functionalized Quinazolines and Pyrimidines for Optoelectronic Materials

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 pi-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 pi-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.