Azapyrene-based fluorophores: synthesis and photophysical properties

Abstract

Azapyrenes are the nitrogen isosteres of pyrene. Based on theoretical and experimental studies, electron–acceptor azapyrene domains may be considered as convenient scaffolds for constructing a large variety of “push–pull” π-conjugated chromophores with pronounced ICT properties. Over the past decade, due to the unrelenting interest in functional materials and modern methodologies such as cross-coupling, peri-annulation, direct C–H-functionalization, etc., methods for the synthesis of aryl(alkyl) K-functionalized azapyrenes and other derivatives have been developed, and their photophysical and electrochemical properties have been studied. This short review aims at critical analysis of the best known/modern methods for the preparation of functionalized azapyrene derivatives, as well as an assessment of their photophysical/electrochemical properties in comparison with the structural and electronic properties of the parent pyrene.