Recent Advances in the Assembly of Organoselenyl-Substituted (Thio)Chromones and 4-Quinolones

Organoselenylated chromones, thiochromones, and 4-quinolones, as an important members of selenyl-bearing heterocycles, present significant biological activities. A variety of methods for the facile synthesis of selenyl-substituted chromones, thiochromones, and 4-quinolones, employ chromones, 2-hydroxyaryl enaminones, alknyl aryl ketones, and 4-quinolones as the starting material via transition-metal-catalyzed, oxidant-promoted, electrocatalytic, and photo-induced selenylation or selenocyanation, and cascade selenylation or selenocyanation/cyclization involving a radical pathway or cationic pathway, which are mainly summarized in this review. The detailed mechanism and the existed limitations of the reported strategies are also discussed here. Additionally, future prospects in the construction of organoselenyl-substituted chromones, thiochromones, and 4-quinolones, is showed to encourage chemists to push the development of heterocyclic chemistry and organoselenium chemistry.