Green Chemistry: Microwave Synthesis, Latest Approaches towards Sustainable Processes

Dear Colleagues,

The search for energy alternatives to activate chemical reactions has become one of the main goals of research and development in synthetic chemistry. The use of microwaves has optimized classical heating methods such as Bunsen burners, hot plates, oil baths and electric heating ovens, which involve slow processes of energy transfer through reactor materials and solvents to finally reach the molecules, generating side processes such as loss of energy to the surroundings and the activation of secondary reactions. In the last two decades, the production of pharmaceuticals, food additives, cosmetics, excipients, polymers, materials, nanoparticles, building blocks and fine chemicals, the use of microwaves as an energy source has been one of the most efficient and sustainable alternatives because it is possible to carry out transformation quickly, with high yield and efficient selectivity, and it will surely become one of the modern areas in green chemistry. 

The use of microwaves in chemical synthesis generates benefits at different levels of performance: 

1. At an academic and scientific level, it allows us to better understand the energy activation mechanisms of transformations, giving the possibility of proposing and optimizing theoretical and semi-empirical models at the quantum, physicochemical and kinetic level.
2. At an experimental level, it allows us to dispense with strenuous and expensive transformation protocols. With the use of microwaves, it is possible to save on resources such as reaction time, proportion of solvents, as well as stoichiometric equivalents of activators and reagents. It is also possible to generate reaction crudes with a smaller quantity and variety of alternate products, which facilitates the isolation and purification of the desired products.
3. Regarding environmental care, the microwave activation of chemical reactions is one of the most robust alternatives in terms of energy savings and minimal waste generation, which is undeniably a great advancement in the efforts to prevent natural resources from damage, thus allowing them to be reestablished and remedied to save our planet.
4. A fourth level of benefits provided by microwave synthesis is the saving of institutional and financial resources. With the use of this methodology, it is possible to optimize reagents, laboratory space, electricity consumption and waste disposal services.

Within the areas of opportunity for microwave synthesis, it is possible to mention that scaling up to industrial proportions still has room for development, since the requirements of processes at the chemical plant or pilot plant level imply the transfer of energy to high-volume reaction matrices in which chemical engineering is necessary. It should be recognized, however, that the first multidisciplinary efforts to bring microwave synthesis to large-scale use are already beginning to be documented on this topic.

This Special Issue on “Green Chemistry: Microwave Synthesis, Latest Approaches Towards Sustainable Processes” will document the most recent and significant advances in microwave synthesis. In order for each collaboration to have a significant impact on the scientific community, each author may include in their work their immediate background, reasoning, justifications, data, graphs, interpretations, and complementary experimental evidence that allow their observations to be evaluated, compared, and reproduced. The topics covered in this Special Issue include, but are not limited to:

1. Experimental development of general synthesis methodologies;
2. Optimization of previously documented synthesis processes without the use of microwaves;
3. Production of compounds, either as final products or reactive intermediates, which are of interest for health, food or technology;
4. Development of theoretical, predictive, calculus or semi-empirical models that explain the use and interaction mechanics of microwaves in chemical transformation systems;
5. Proposals for scaling up processes from the laboratory to a pilot plant or chemical plant using microwaves;
6. Prototypes of microwave reactors, focusing on the publication of the results of the chemical transformations carried out within them;
7. Development of software, commercial or open source, for use in items (d) and (f) of this list.

Sincerely,

Prof. Dr. Jaime Escalante
Prof. Dr. Eusebio Juaristi
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Processes is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• MAOS
• microwave synthesis
• energy optimization
• microwave activation
• process systems engineering
• activation of reactions