Pyran-2-ones as a Versatile Synthon for the Synthesis of Diverse Arenes and Heteroarenes

The importance of pyran-2-one as synthon has been significantly realized due to its unique structural features that fascinated organic chemists for extensive investigation. These compounds are endowed with electrophilic and nucleophilic centers in their molecular make up that responsible for substitution, addition, photochemical and ring transformation reactions. The past reviews have mostly covered the addition, photochemical and some substitution reactions. This review provides the comprehensive updated literature on the chemistry of pyran-2-one with special emphasis on ring transformation reactions.