Recent Advances in the MCRs Synthesis of Chromenes: A Review

Considering highly important biological and medicinal properties of chromenes, synthesis of these heterocycles has attracted the interest of medicinal and organic chemists. This review includes the recent investigation in the multicomponent synthesis of chromene systems and describes the literature reports for the period of 2000 to early 2018. These reported strategies carried out in the classical and non-classical conditions particularly under a green condition such as using green solvents, catalyst and solvent-free conditions.