Nitrogen-containing heterocyclic compounds have consistently been a noticeable center of attention due to their significant utilization in the domain of synthetic organic chemistry, agrochemicals, and pharmaceuticals. α,β-Unsaturated imines or conjugated imines provide a lot of significant cyclic as well as acyclic products through reacting with a versatile family of compounds. This review summarizes the recent advances in enantioselective reactions of α,β-unsaturated imines by using synthetic methodologies for synthesizing various nitrogencontaining heterocycles that contain four to six-membered rings. The synthesis of rarely found seven-, eight-and ninemembered nitrogen-containing heterocycles have also been reported.

A simple and mild metal free cascade reaction has been developed for the construction of highly functionalized olefines. The approach relies on the initial formation of [3+2] cycloadducts from in-situ generated pyridinium ylide (from polymer bounded DMAP) with N-substituted maleimides/α,β-unsaturated β-keto esters. The cycloadducts decompose to regenerate supported DMAP and yield functionalized itaconimides/olefines. The methodology has broad substrates scope. The alkene has been further transformed to trisubstituted furan. PS-DMAP is reused for five cycles.

Polymer-supported catalysts have emerged as one of the sustainable and cost-effective alternatives in organic synthetic chemistry. We have developed the first polymer-supported DMAP catalyzed one-pot synthesis of diversely substituted α-pyrones. The cascade approach involves C5 conjugate addition of 5H-oxazol-4-ones to α,β-unsaturated-β-ketoesters followed by lactonization/elimination.