Structural, Optical Properties, and Biological Activity of Complexes Based on Derivatives of Quinoline, Quinoxaline, and Quinazoline with Metal Centers from Across the Periodic Table

This review is focused on consideration of the influence of ligands and synthetic conditions on the structure and optical properties of a variety of metal complexes based on derivatives of quinoline, quinoxaline, and quinazoline. It has been established that changing of substituents in a given ligand provides an opportunity to tune color and intensity of the photoluminescence of the corresponding Al(III) and Zn(II) complexes, while variation of auxiliary ligands in cyclometalated complexes leads to emission emergence at ambient temperature. Difluoroboron complexes of metals with N,O-bidentate ligands proved to exhibit a strong photoluminescence in both solutions and the solid state. Some complexes of this type are useful for electroluminescent or solar cell devices. Biological activity of quinoline complexes is governed mainly by the metal nature.