Improved laboratory protocols for convenient and rapid transformations are highly desired in modern synthetic chemistry. Microwave irradiated reactions have received considerable attention in recent years and it is a subject of intense discussion in the scientific community. Microwave heating is more efficient in terms of the energy used, produces higher temperature homogeneity and is considerably more rapid than conventional heating methods. This technique as an alternative to conventional energy sources for introduction of energy into reactions has become a recognized practical method in various fields of chemistry. Microwave-assisted organic synthesis (MAOS) is known for the spectacular accelerations produced in many reactions as a consequence of the increased heating rate, a phenomenon that cannot be easily reproduced by classical heating means. As a result, higher yields, milder reaction conditions and shorter reaction times can often be attained. Its specific heating method attracts extensive interest not only because of rapid volumetric heating, but also for suppressed side reactions, energy saving, decreased environmental pollutions and safe operations. In this review, we will try to represent an overview on origin and fundamental features of microwave ovens and its usefulness in MAOS.
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