Abstract
The overwhelming potential of heterocyclic compounds in pharmaceutical sector continuously demands the development of new synthetic approaches. The beginning of 19th century witnessed an era of development of various condensation reactions for the development of new heterocyclic scaffolds. Most of the developed classical reactions still hold great value while the field is inundated in 21st century with the advent of catalysis. The activation of unsaturated functionalities of acyclic compounds to undergo intramolecular cyclization via metal catalyzed approaches or the transformation of azetidin-2-ones to functionally enriched compounds have occupied a prominent place in heterocyclic synthesis.
Keywords: Aza-Michael Addition, Biological Activities, β-Amino Ester, β- Lactam-Synthon Protocol, Cross-Dehydrogenative-Coupling, Cyclo- Isomerisation, Cycloaddition, Diastereoselective, Enatioselective, Enatiomeric Excess, Fries Rearrangement, Heterocycles, Intramolecular Amidolysis, Intermolecular Amidolysis, Intramolecular Cyclization, Intramolecular Ullmann, Metal-Catalyzed Reactions, Photocatalyst.