Synthesis of Dibenzo[g,p]Chrysenes via Organophotocatalytic Sequential Single‐Electron Oxidation

Polycyclic aromatic hydrocarbons such as dibenzo[g,p]chrysenes (DBCs) have recently attracted much attention in synthetic organic chemistry and materials chemistry, particularly as important structural motifs in functional materials for electronic and optoelectronic devices. However, the preparation of DBCs and its derivatives generally requires multistep syntheses and the use of transition metal catalysts. This report describes a highly efficient method comprising a sequential single‐electron oxidative spirocyclization and 1,2‐aryl migration for the construction of DBCs. The combination of Mes‐Acr+ and diphenyldisulfide in the photocatalytic system enables a first single‐electron oxidation to occur preferentially at the more electron‐rich alkene moiety of a readily available starting material, followed by a second single‐electron oxidation after intramolecular spirocyclization. A variety of DBCs have been readily synthesized using the present methodology. Dibenzo[g,p]chrysenes (DBCs), a type of PAHs, can be synthesized from easily synthesizable starting materials by using acridinium salt as an organophotocatalyst. In this method, DBCs can be synthesized by the photocatalytic reaction of acridinium salt without the use of metal catalysts.