Deep Eutectic Solvent as a Recyclable Catalyst for Three-Component Synthesis of β-Amino Carbonyls

Deep Eutectic Solvents as à-la-Carte Medium for Transition-Metal-Catalyzed Organic Processes

Our society is facing a tremendous challenge to become more sustainable in every sphere of life. Regarding the chemical industry, one of the most significant issues to be addressed is the use of volatile organic compounds (VOCs) as solvents because they are petrol-derived and most of them are toxic and flammable. Among the possible solutions, deep eutectic solvents (DESs) have emerged as sustainable alternatives to VOCs in organic catalyzed transformations and other fields. The advantages of these new reaction media are not only related to their more benign physical and chemical properties and, for most of them, their renewable sources but also due to the possibility of being recycled after their use, increasing the sustainability of the catalyzed process in which they are involved. However, their use as media in catalytic transformations introduces new challenges regarding the compatibility and activity of known catalysts. Therefore, designed catalysts and "à-la-carte" DESs systems have been developed to overcome this problem, to maximize the reaction outcomes and to allow the recyclability of the catalyst/media system. Over the last decade, the popularity of these solvents has steadily increased, with several examples of efficient metal-catalyzed organic transformations, showing the efficiency of the catalysts/DES system, compared to the related transformations carried out in VOCs. Additionally, due to the inherent properties of the DES, unknown transformations can be carried out using the appropriated catalyst/DES system. All these examples of sustainable catalytic processes are compiled in this review.

Recent Advances in Utilization of Deep Eutectic Solvents: An Environmentally Friendly Pathway for Multi-component Synthesis

Abstract:

With the increasing analysis of saving environment, the researchers demonstrated much effort to replace toxic chemicals with environmentally benign ones. Eutectic mixtures are those solvents that fulfill the criteria of green solvents. The synthesis of organic compounds in the chemical and pharmaceutical industries makes it necessary to find unconventional solvents that cause no harmful impact on health parameters. This review showed that using deep eutectic mixture-based solvents to overcome the hazardous effects of harmful volatile organic solvents over the past few years has gained much more appeal. In most applications, deep eutectic mixtures aRecent Advances in Utilization of Deep Eutectic Solvents: An Environmentally Friendly Pathway for Multi-component Synthesisre used for a solvent or co- solvent role, as they are easy to use, easy dissolution of reactants, and non-evaporative nature. However, deep eutectic mixtures have also been investigated as catalysts, and this dual functionality has much scope in the future, as a significantly less range of deep eutectic mixtures is utilized for this.

Expedient multicomponent synthesis of a small library of some novel highly substituted pyrido[2,3-d]pyrimidine derivatives mediated and promoted by deep eutectic solvent and in vitro and quantum mechanical study of their antibacterial and antifungal activities

A facile and efficient catalyst- and oxidant-free multicomponent synthesis of a small library of highly substituted pyrido[2,3-d]pyrimidine derivatives is reported. The products were obtained within relatively short reaction times in good to excellent yields in the presence of deep eutectic solvents as media and promoters. Simple purification and reusability of the deep eutectic solvent were the other beneficial factors of the reported protocol. All of the synthesized derivatives were thoroughly screened for possible in vitro antibacterial and antifungal effects against twenty-two bacterial and three fungal pathogens. Some of the prepared pyrido[2,3-d]pyrimidine derivatives showed remarkable antibacterial and antifungal activities in comparison with some typical known antibacterial and antifungal agents. Finally, the derivatives possessing bioactivity effects were subjected to quantum chemical computational studies in order to reveal the probable structural and electronic effects governing the spotted bioactivities. It was found that the observed bioactivities could be best devoted to the HOMO-LUMO energy gap and para delocalization index of the corresponding derivatives.

Recent advances in the application of deep eutectic solvents as sustainable media as well as catalysts in organic reactions

This review highlights the recent advances using deep eutectic solvents (DESs), deep eutectic ionic liquids (DEILs), low-melting mixtures (LMMs) or low transition temperature mixtures (LTTMs) as green media as well as catalysts in organic reactions.