Multi-Component Reactions (MCRs) have emerged as an excellent tool in organic chemistry
for the synthesis of various bioactive molecules. Among these, one-pot MCRs are included, in
which organic reactants react with domino in a single-step process. This has become an alternative
platform for the organic chemists, because of their simple operation, less purification methods, no side
product and faster reaction time. One of the important applications of the MCRs can be drawn in carbon-
carbon (C-C) and carbon-heteroatom (C-X; X = N, O, S) bond formation, which is extensively
used by the organic chemists to generate bioactive or useful material synthesis. Some of the key carbon-
carbon bond forming reactions are Grignard, Wittig, Enolate alkylation, Aldol, Claisen condensation,
Michael and more organic reactions. Alternatively, carbon-heteroatoms containing C-N, C-O,
and C-S bond are also found more important and present in various heterocyclic compounds, which
are of biological, pharmaceutical, and material interest. Thus, there is a clear scope for the discovery
and development of cleaner reaction, faster reaction rate, atom economy and efficient one-pot synthesis
for sustainable production of diverse and structurally complex organic molecules. Reactions that
required hours to run completely in a conventional method can now be carried out within minutes.
Thus, the application of microwave (MW) radiation in organic synthesis has become more promising
considerable amount in resource-friendly and eco-friendly processes. The technique of microwaveassisted
organic synthesis (MAOS) has successfully been employed in various material syntheses,
such as transition metal-catalyzed cross-coupling, dipolar cycloaddition reaction, biomolecule synthesis,
polymer formation, and the nanoparticle synthesis. The application of the microwave-technique in
carbon-carbon and carbon-heteroatom bond formations via MCRs with major reported literature examples
are discussed in this review.
Bimetallic copper and zinc-catalyzed oxidative cycloaddition of 3-aminopyridazines and nitriles: a direct synthesis of 1,2,4-triazolo[1,5-b]pyridazines via C–N and N–N bond-forming process