1,720,961 research outputs found
Mechanochemistry: Unravelling the Impact of Metal Leaching in Organic Synthesis
Full text linkSolvent-free techniques have gained considerable attention in recent years due to their environmental advantages and potential to enable chemical reactivities beyond the reach of traditional solution-based methods. Mechanochemistry has emerged as a groundbreaking approach to drive sustainable chemical processes. Despite its promise, some challenges still need to be explored, including the overlooked issue of material leaching during grinding, a phenomenon in which components from milling media or reaction vessels, such as stainless steel, unintentionally alter reaction outcomes. This study investigates the role of metal leaching in reducing arylnitrosamines by using a poorly soluble solid reagent, thiourea dioxide (TDO), focusing on stainless steel vessels. By comparing conventional mechanochemical methods with innovative solvent-free vibratory techniques, we assess the extent of metal contamination and its impact on reaction efficiency. These findings provide new insights into how material leaching influences chemical processes and offer valuable guidance for optimizing these forward-looking and green methodologies
Mechanochemistry for Healthcare: Revealing the Nitroso Derivatives Genesis in the Solid State
Full text linkNitroso derivatives with unique characteristics have been extensively studied in various fields, including biology and clinical research. Although there has been substantial investigation of “nitrosable” components in many drugs and commonly consumed nutrients, there is still a need for a higher awareness about their formation and characterization. This study demonstrates how these derivatives can be produced through a mechanochemical procedure under solid-state conditions. The results include synthesizing previously unknown compounds with potential biological and pharmaceutical applications, such as a nitrosamine derived from a Diclofenac-like structure
Mechanochemistry in Organic Synthesis: An Italian Journey through Innovations
Full text linkMechanochemistry, as an enabling technology, harnesses mechanical force to drive chemical reactions, presenting compelling advantages in organic synthesis within the principles of green chemistry. This review explores how its unique advantages and alignment with sustainable practices have been widely developed in different scientific fields in Italy. As a transformative strategy for organic synthesis, mechanochemistry has been portrayed in this review as a valuable synthetic alternative due to the various advantages, such as solvent reduction and new reaction pathways, that its use brings. Nonetheless, the improvements brought about by its use have also been crucial in other fields of chemistry described by Italian scientists. In this whole context, Italian researchers have analysed both already optimised processes and new feasible pathways, paving the way for new avenues previously hampered by all the limitations that belong to in-solution chemistry
Mechanically accelerated catalytic hydrogenation: correlating physical state, reaction rate, and interface area
No full textThis study thoroughly examines the role of mechanochemistry in organic synthesis by analysing the factors affecting the mechanochemical reduction process of unsaturated and oxidized compounds. Hydride species and hydrogen gas are generated in situ by mixing a diboron compound with a stoichiometric amount of water. The process is tested against several substrates to determine how the physical state of the reagents influences the reduction technique. The study aims to thoroughly investigate the correlation between the mixing process, reaction rate, and interface area
Mechanically processed Sardinian wool promotes C-C bond synthesis under solvent-free conditions
No full textThe tangible environmental concerns of the last few decades are prompting science to a new sustainable paradigm for chemical reactions and a circular economy. In the present manuscript, complying with this dichotomy, Sardinian wool is presented as a promising material for organic synthesis. Aldol and nitro-aldol additions, and Knoevenagel reactions were demonstrated with high efficiency under wool-promoted and solvent-free conditions, paving the way to novel approaches for converting wool biomass waste into value-added products for C-C bond formation
Oxidized thiourea derivatives: uncovering new frontiers with resonant acoustic mixing (RAM)
No full textNitrogen-containing compounds are essential for producing active pharmaceutical ingredients. However, traditional synthesis methods for these compounds often involve environmentally harmful practices, such as high temperatures, long reaction times, and using toxic reagents and large amounts of solvents. Recently, solvent-free techniques have gained attention as effective and more sustainable alternatives. A significant advancement in this field is resonance acoustic mixing (RAM), a technology that enhances the reactivity of the reaction components without the need for grinding media. RAM operates through vertical oscillations at a constant frequency of 60 Hz, with the G factor adjustable up to 100G. This study investigates the reactivity of thiourea trioxide (TTO), an oxidized thiourea derivative, for preparing 2-amino benzoxazoles. This process efficiently yields the desired aza-heterocycles, with the products easily recovered by simple filtration of the crude reaction mixture. This research highlights the potential of RAM and mechanochemistry to create a more sustainable and efficient synthetic pathway for nitrogen-containing pharmaceutical compounds, promoting greener chemistry practices. Additionally, we evaluated the reactivity of another oxidized derivative of thiourea, thiourea dioxide (TDO), allowing for a comparison between these two compounds
Appealing Renewable Materials in Green Chemistry
No full textIn just a few years, chemists have significantly changed their approach to the synthesis of organic molecules in the laboratory and industry. Researchers are encouraged to approach “greener” reagents, solvents, and methodologies, to go hand in hand with the world’s environmental matter, such as water, soil, and air pollution. The employment of plant and animal derivates that are commonly regarded as “waste material” has paved the way for the development of new green strategies. In this review, the most important innovations in this field have been highlighted, paying due attention to those materials that have played a crucial role in organic reactions: wool, silk, and feather. Moreover, we decided to focus on the other most important supports and catalysts in green syntheses, such as proteins and their derivates. Different materials have shown prominent activity in the adsorption of metals and organic dyes, which has constituted a relevant scope in the last two decades. We intend to furnish a complete screening of the application given to these materials and contribute to their potential future utilization
Application of Bertagnini's Salts in a Mechanochemical Approach Toward Aza-Heterocycles and Reductive Aminations via Imine Formation
Full text linkOur research has demonstrated that mechanochemical activation is more effective with solid reagents. We have showcased the practicality of Bertagnini's salts, also called aldehyde-bisulfite adducts, which are crystalline, simplifying preparation and storage. These salts are stable substitutes for liquid aldehydes and ketones that have been employed in reductive amination, synthesizing aza-heterocycles and hydrazones within mechanochemistry. The technique‘s effectiveness broadens the substrate scopes, simplifies purification, reduces reaction times, and yields the desired products ranging from 38–91%. Additionally, the thermal stability of the bisulfite adducts has been confirmed through TGA (Thermogravimetric analysis) analysis
Mechanochemistry Frees Thiourea Dioxide (TDO) from the ‘Veils’ of Solvent, Exposing All Its Reactivity
Full text linkThe synthesis of nitrogen-based heterocycles has always been considered essential in developing pharmaceuticals in medicine and agriculture. This explains why various synthetic approaches have been proposed in recent decades. However performing as methods, they often imply harsh conditions or the employment of toxic solvents and dangerous reagents. Mechanochemistry is undoubtedly one of the most promising technologies currently used for reducing any possible environmental impact, addressing the worldwide interest in counteracting environmental pollution. Following this line, we propose a new mechanochemical protocol for synthesizing various heterocyclic classes by exploiting thiourea dioxide (TDO)'s reducing proprieties and electrophilic nature. Simultaneously exploiting the low cost of a component of the textile industry such as TDO and all the advantages brought by a green technique such as mechanochemistry, we plot a route towards a more sustainable and eco-friendly methodology for preparing heterocyclic moieties
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