ABSTRACT
This chapter reviews a large variety of multicomponent reactions (MCRs) for the synthesis of polysubstituted pyridine. It describes an efficient signal pot MCR for polysubstituted pyridine through a condensation of malononitrile, aldehyde, and thiols via conventional as well as microwave irradiation. The chapter also describes a simple protocol for the effective synthesis of 2-(1H-Indol-3-yl)-6-methoxy-4-arylpyridine-3,5-dicarbonitrile through one-pot, multicomponent reaction under reflux conditions in the presence of basic conditions. It discusses the basic ionic liquid (such as [bmim]OH) feasible for promoting a one-pot, three-component condensation reaction for the highly substituted pyridines in high yields at ambient temperature. The effects of an ionic base such as tetrabutylammoniumhydroxide (TBAH), and an amine base such as piperidine, on the direct synthesis of pyridine-3,5-dicarbonitriles through a multicomponent reaction of malononitrile, aldehydes, and thiols was systematically investigated by Chen and co-workers. The one-pot, multicomponent reaction approach for the synthesis of indenopyridines has attracted the attention of the synthetic organic community.
