The present work aims at understanding the role of viscosity or solvent friction in ionic liquids for an intramolecular Diels-Alder (IMDA) reaction of (E)-1-phenyl-4-[2-(3-methyl-2-butenyloxy)benzylidene]-5-pyrazolone (1). The results have been analyzed on the basis of the current theoretical models, and their failure to account for the observed trends is discussed in terms of "effective" viscosity or microviscosity. The rates of the reaction decrease with the increasing viscosity of the ionic liquids. As evident from the anionic effect, the solute-solvent specific interactions play a role in governing the kinetics of the reaction. The lower viscosities of the bistrifluoromethanesulfonimide [NTf2](-) based ionic liquids as compared to those based on tetrafluoroborate [BF4](-) anion fail to result in a corresponding acceleration in the rates of the reaction. These contradictory results indicate that solvent microviscosity, rather than the bulk macroscopic viscosity, should be the criteria for selecting the ionic liquids as reaction media.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/jo801802q | DOI Listing |
Acc Chem Res
January 2025
Helmholtz Institute Ulm (HIU) Electrochemical Energy Storage, Helmholtzstrasse 11, 89081 Ulm, Germany.
ConspectusLithium-ion batteries (LIBs) based on graphite anodes are a widely used state-of-the-art battery technology, but their energy density is approaching theoretical limits, prompting interest in lithium-metal batteries (LMBs) that can achieve higher energy density. In addition, the limited availability of lithium reserves raises supply concerns; therefore, research on postlithium metal batteries is underway. A major issue with these metal anodes, including lithium, is dendritic formation and insufficient reversibility, which leads to safety risks due to short circuits and the use of flammable electrolytes.
View Article and Find Full Text PDFPharmaceutics
December 2024
Faculty of Pharmaceutical Sciences, Josai International University, 1 Gumyo, Togane 283-8555, Chiba, Japan.
: Laurocapram (Azone) attracted attention 40 years ago as a compound with the highest skin-penetration-enhancing effect at that time; however, its development was shelved due to strong skin irritation. We had already prepared and tested an ante-enhancer (IL-Azone), an ionic liquid (IL) with a similar structure to Azone, consisting of ε-caprolactam and myristic acid, as an enhancer candidate that maintains the high skin-penetration-enhancing effect of Azone with low skin irritation. In the present study, fatty acids with different carbon numbers (caprylic acid: C8, capric acid: C10, lauric acid: C12, myristic acid: C14, and oleic acid: C18:1) were selected and used with ε-caprolactam to prepare various IL-Azones in the search for a more effective IL-Azone.
View Article and Find Full Text PDFMolecules
January 2025
CNR-STIIMA, Italian National Research Council, Institute of Intelligent Industrial Technologies and Systems for Advanced Manufacturing, 13900 Biella, Italy.
Thanks to their unique physicochemical properties, ionic liquids (ILs) have moved from niche academic interest to critical components in various industrial applications. The textile industry, facing significant environmental and economic pressures, has begun to explore ILs as sustainable alternatives to traditional solvents and chemicals. This review summarizes research on the use of ILs in various textile processes, including dyeing, finishing, and fiber recycling, where their high thermal stability, tunable solubility, and low volatility are exploited to reduce resource consumption and environmental impact.
View Article and Find Full Text PDFMolecules
January 2025
Department of Chemical Engineering, Louisiana Tech University, 600 Dan Reneau Drive, P.O. Box 10348, Ruston, LA 71272, USA.
Adequate water supplies are crucial for missions to the Moon, since water is essential for astronauts' health. Ionic liquids (ILs) have been investigated for processing metal oxides, the main components of lunar regolith, to separate oxygen and metals. The IL must be diluted in the process.
View Article and Find Full Text PDFInorg Chem
January 2025
Center for Hierarchical Waste Form Materials, University of South Carolina, Columbia, South Carolina 29208, United States.
Ionic liquids were used as low temperature solvents for the synthesis of new lanthanide and transuranic-element (TRU) borate cluster structures. Ionothermal synthesis with the ionic liquid [BMIm]Cl (1-butyl-3-methylimidazolium chloride) yielded the La, Nd, and Am containing phases LaBOCl, NdBOCl, and AmBOCl. The structures of the La, Nd, and Am borate clusters were determined by single crystal X-ray diffraction (SCXRD) and found to be cubic, in the chiral space group 23.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!