Polycyclic Benzimidazole: Synthesis and Photophysical Properties

Benzimidazole has tremendous application in medicinal chemistry and material science. The fusion of ring/substitution to benzimidazole nucleus produce polycyclic benzimidazole e. g., pyrido[1,2-a]benzimidazole, benzimidazo[1,2-a]quinoline, pyrrolo[1,2-c]benzimidazolequinones (PBIs) and benzimidazo[2,1-a]isoquinolines and these are the important synthetic strategies in drug discovery. Benzimidazole analogues have versatile therapeutic properties which encouraged the researchers to develop new therapeutic agents. Hence, the synthetic literature survey towards the polycyclic benzimidazole is paramount important. Due to the beautiful fluorescent properties of fused benzimidazole moiety, they are also used in optoelectronics, optical lasers, and organic luminophores. In addition, this scaffold has broad applications in organometallic catalysis, co-ordination chemistry, and asymmetric catalysis. Herein, we report a vast synthetic route of benzimidazole embedded polyhetrocycles in the last eight years and their photophysical application in the modern research field.