RECENT PROGRESS IN MICROWAVE-ASSISTED ORGANIC SYNTHESIS: A REVIEW OF APPLICATIONS, LIMITATIONS, AND EMERGING TRENDS
Abstract
Microwave (MW) irradiation has emerged as one of the most prominent non-conventional heating methods in modern synthetic chemistry. Over the past ten years microwave-assisted organic synthesis (MAOS) has evolved from a rapid but inconsistent technique used mostly in academic laboratories, to a robust, well-instrumented technique with reproducible methods and a defined role in the green chemistry arena. This review presents the main advances from 2015 to 2024, focusing on the practical questions that a synthetic chemist actually asks. Which reactions are most improved by microwave dielectric heating? What equipment is available now? How do reaction times, yields, selectivities and energy footprints really compare to conventional heating? We discuss heterocyclic and multicomponent reactions, transition metal-catalyzed coupling reactions, solvent-free and on-water reactions, the synthesis of nanoparticles and metal-organic frameworks, biomass valorisation and a selection of cases from medicinal chemistry. Trends in publications and representative comparisons are explored. We strive to offer a balanced view: while the productivity benefits are substantial and well proven, some of the claims that have been made in the literature, especially concerning so-called "non-thermal" microwave effects, are still open to a cautious interpretation. The assessment concludes with a brief overview on continuous-flow microwave processing and a discussion of the remaining challenges to industrial scale-up.
Keywords:
Microwave-assisted organic synthesis, dielectric heating, green chemistry, multicomponent reactions, cross-coupling, nanomaterials, continuous flowDOI
https://doi.org/10.70604/jmtbas.v3i2.191References
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