Energy-efficient Approach to Multicomponent Reaction for the Synthesis of Therapeutically Relevant Heterocycles

Multi-component reactions have been used as an important synthetic strategy for the synthesis of diverse varieties of therapeutically useful heterocyclic scaffolds. High atom economy, one-pot reaction, and involvement of synthetically simple steps are some of the interesting features that make MCRs greener compared to conventional methods. The development of environmentally benign and eco-friendly synthetic methods has been a very demanding area of research in the past few decades. In particular, the development of energyefficient methods has attracted the attention of the research community due to heavy dependence on non-renewable energy resources, which is depleting fast. Therefore, the present review has highlighted the multi-component reactions developed under the energy efficient protocol, which mainly include the reactions developed under the microwave, ultra-sonication, mechanochemical, and photochemical reaction conditions for the synthesis of therapeutically relevant heterocycles.