Synthesis of a Novel Functionalized Dibenzo[hi,st]ovalene (DBOV) and Study of its Optical properties

Abstract

Polycyclic aromatic hydrocarbons (PAHs) with zigzag edges have been investigated in recent years because of their fascinating optoelectronic properties; however, the number of the reported PAHs with zigzag edges in the literature is limited, and several of them suffer from low stability, obstructing their in-depth characterization and application. Dibenzo[hi, st]ovalene (DBOV) is one of the stable PAHs having a combination of zigzag and armchair edges, which has intriguing properties such as strong red-luminescence, high fluorescence quantum yield, stimulated emission, and closed-shell character, and is promising for applications in light-emitting diodes, organic lasers, and sensing. Narita and co-workers have previously reported a few DBOV derivatives, but other DBOV derivatives at different peripheral positions, such as 4, 12-positions, have not been explored yet. In this project, a novel functionalized DBOV, namely Cl-DBOV 10 (4,12- dichloro-dibenzo[hi,st]ovalene), was designed and synthesized through a multistep reactions which include Sonogashira coupling, Borylation via Lithiation, n-BuLi/DMF Formylation reaction, Suzuki coupling, TIPS deprotection using TBAF, Glaser coupling, ICl-promoted iodinationbenzannulation, photochemical cyclodehydroiodination reaction, Grignard reaction, and acid-catalyzed oxidative cyclization reactions.