Green and Sustainable Approaches in Multicomponent Reactions: Solar Energy, Ultrasound, Solid‐Phase, and Photochemical Methods: A Review

Sustainable or green chemistry has evolved as a valuable tool over the last few decades, giving environmentally friendly strategies for reducing the use of hazardous chemicals in both academic and industrial research, eliminating waste, and potentially recycling them for better results. In this context, the field of multicomponent reactions (MCRs) is growing tremendously for the construction of biologically active molecules with great structural complexity. To enhance the diversity of MCRs, various new methodologies are incorporated with MCR. In this review article, a collection of examples on recent development in MCRs in solar energy, ultrasound, solid‐phase/solvent free, and photochemical methods are described, which will serve as a guide for researchers developing novel green methodologies.