Microwave assisted organic synthesis

Synthesis of arylimidazoles [-145] in dry media in domestic oven [].
Photo provided by Flickr

Figure 5: Synthesis of arylimidazoles [146].

This Account describes the current status of MW-assisted synthesis highlighting the introduction of various prototypes of equipment, classes of organic reactions pursued using nanomaterials, and the synthesis of unique and multifunctional nanomaterials; the ensuing nanomaterials possess zero-dimensional to three-dimensional shapes, such as spherical, hexagonal, nanoprisms, star shapes, and nanorods. The synthesis of well-defined nanomaterials and nanocatalysts is an integral part of nanotechnology and catalysis science, because it is imperative to control their size, shape, and compositional engineering for unique deployment in the field of nanocatalysis and organic synthesis.

New synthesis of some pyrido[1,2-α]benzimidazoles and related derivative
Photo provided by Flickr

Synthesis and biological activity of benzimidazoles

The removal of polymer support and exposure of quinoxalines for auto-oxidation finally produce the benzimidazole linked quinoxalinone derivatives with high purity and yields.

Sriram, “Microwave assisted one-pot synthesis of highly potent novel isoniazid analogues,” Bioorg.
Photo provided by Flickr

There various methods adopted in synthetic organic chemistry including microwave assisted synthesis, sonochemistry and green chemistry. Applications of all microwaves in the synthesis of chemical moieties which are biologically active have been discussed with a short briefing of advantages of these techniques over the conventional approaches.

Pregosin, “Stable platinum(II) complexed α-aminoethers derived from benzimidazole and benzoxazole,”Inorg.
Photo provided by Flickr


Microwave assisted organic synthesis.

MW-assisted methods have been employed for the convenient and reproducible synthesis of well-defined noble and transition core–shell metallic nanoparticles with tunable shell thicknesses. Some of the distinctive attributes of MW-selective heating in the synthesis and applications of magnetic nanocatalysts in organic synthesis under benign reaction conditions are highlighted. Sustainable nanomaterials and their applications in benign media are an ideal blend for the development of greener methodologies in organic synthesis; MW heating provides superb value to the overall sustainable process development via process intensification including the flow systems.

Conventional and microwave-assisted synthesis of new …

Keywords: Benzimidazole salt, N-heterocyclic carbenes, palladium nanoparticles, cross-coupling reaction, Suzuki--Miyaura coupling, microwave

PART I: MICROWAVE-ASSISTED SYNTHESIS OF BENZIMIDAZOLES…

“That process intensification at high temperature and pressure is the essence of microwave synthesis,” Kappe emphasizes. “That is why a microwave reactor can be a powerful tool in organic synthesis.”

Microwave-assisted synthesis of new ..

Another benefit of microwave-assisted chemistry is its versatility—it can be applied to nearly any type of chemistry, Banik points out. For example, he worked on β-lactam antibiotic chemistry in Bose’s lab, and since that time, he has taken microwave β-lactam synthesis in a new direction by preparing the first β-lactam anticancer agents.

on conventional and microwave synthesis of some benzimidazole, ..

Kappe’s group has demonstrated that microwave-assisted methods work for many types of organic reactions, including Diels-Alder reactions, palladium-catalyzed cross-couplings, and aromatic substitutions. For example, in 2010, Kappe’s group carried out a set of experiments to compare microwave-assisted reactions with conventional reflux reactions. In one experiment, the researchers synthesized 2-methylbenzimidazole from -phenylenediamine and acetic acid, a common synthesis in pharmaceutical process chemistry ( DOI: ).