Isoquinoline derivatives have attracted great interest for their wide biological and fluorescent properties. In the current study, we focused on the synthesis of a series of novel isoquinoline derivatives substituted at position 3 of the heteroaromatic ring. Compounds were obtained in a Goldberg-Ullmann-type coupling reaction with appropriate amides in the presence of copper(I) iodide, N,N-dimethylethylenediamine (DMEDA), and potassium carbonate. The structures of novel isoquinolines were confirmed by IR, NMR, and elemental analysis, as well as X-ray crystallography. In the course of our research work, the visible fluorescence of this class of compounds was observed. The above findings prompted us to investigate the optical properties of the selected compounds.
Keywords: X-ray crystallography; copper-catalyzed coupling; fluorescence; isoquinoline derivatives.