Recent advances in chalcogenative annulation strategies for the synthesis of chalcogen-substituted polycyclic (hetero)aromatics.

Chalcogen-containing polycyclic aromatic hydrocarbons (PAHs) and polycyclic heteroaromatics (PHAs) have numerous applications across many fields, including medicinal, material, and polymer chemistry. Given their importance, synthetic chemists are interested in developing synthetic strategies that yield these compounds in an environmentally benign manner at lower cost. To access these compounds, the chalcogenative annulation strategy is considered one of the most atom-economical methods, introducing an organochalcogen functional group along with ring formation. This process can be achieved under various conditions, such as chemical and metal-catalysed methods; however, our main focus is on synthetic strategies, including photochemical and electrochemical methods, and we highlight the mechanistic pathways by which these compounds are synthesised.