Structure of anisole derivatives by total neutron and X-ray scattering: Evidences of weak C–H⋯O and C–H⋯π interactions in the liquid state

Abstract High resolution, total neutron and X-ray scattering data have been used in synergy with Molecular Dynamics simulations to access atomistic scale insight into the structure of anisole and 2,3,5-trimethylanisole, two aromatic compounds bearing an electron-donating methoxy group. A detailed description is provided for the main interactions occurring in these systems, including π-π stacking and weak hydrogen bonding correlations: C H⋯O and C H⋯π. The existence of preferential orientations of the first shell coordinating molecules and the specific nature of the interactions involving the π cloud and the polar methoxy group have been reported and discussed.

A magnetic self-contained thermochromic system with convenient temperature range

A new ionic liquid with sugar-based ligand has been prepared and used to coordinate cobalt(II), at low loading, in an ionic liquid solution. The system obtained reveals magnetic switching and marked thermochromism in solution/polymer films over a convenient temperature range (20–60 °C). This system is self-contained, devoid of any volatile substances, and reproducible over multiple thermal cycles. The colour change can be attributed to a change in the coordination geometry from octahedral (pink) at room temperature to tetrahedral (blue) on warming, monitored by 59Co NMR spectroscopy, which was used for the first time to study the change. This material may find applications in stimuli-respon…

“Sweet” ionic liquid gels: materials for sweetening of fuels

The search for new materials to be used in desulfurisation (sweetening) of fuels is one of the main topics of current research. In this paper, we explored the possibility of using supramolecular gels obtained from the gelation of ionic liquid binary mixtures. Indeed, some ionic liquids are generally known as efficient extraction phases for desulfurisation of fuels. In rare cases, one of their main drawbacks is their partial solubility in the fuel, leading to contamination. Then, their immobilisation due to the formation of a gelatinous network may be a challenge. Ionic liquid gels were obtained by mixing certain [NTf2]−-based ionic liquids (solvents) with the ones of gluconate-based ionic l…

Mesoscopic organization in ionic liquids.

We discuss some published results and provide new observations concerning the high level of structural complexity that lies behind the nanoscale correlations in ionic liquids (ILs) and their mixtures with molecular liquids. It turns out that this organization is a consequence of the hierarchical construction on both spatial (from ångström to several nanometer) and temporal (from fraction of picosecond to hundreds of nanosecond) scales, which requires joint use of experimental and computational tools. © 2017, Springer International Publishing Switzerland.

When the functionalisation comes in useful: ionic liquids with a “sweet” appended moiety demonstrate drastically reduced toxicological effects

The growing number of applications of ionic liquids (ILs) in industry have brought attention to the green credentials of synthesis, as well as their cytotoxicities and ecotoxicities both for their use and accidental leakage into the environment. With the abovementioned properties in mind, we designed a class of ILs with either cations bearing a gluconamide motif and aliphatic side chains or the anion incorporating a gluconic acid (derived from food waste) moiety. An IL with an imidazolium cation with an appended gluconic amide (bearing five hydroxyl groups) moiety was also synthesized for a useful comparison. Different structural features were considered, placing emphasis on the nature and …

Emerging Evidences of Mesoscopic-Scale Complexity in Neat Ionic Liquids and Their Mixtures

Ionic liquids (ILs) represent a blooming class of continuously developing advanced materials, with the aiming of a green chemical industry. Their appealing physical and chemical properties are largely influenced by their micro- and mesoscopic structure that is known to possess a high degree of hierarchical organization. High-impact application fields are largely affected by the complex morphology of neat ionic liquids and their mixtures. This Perspective highlights new arising research directions that point to an enhanced level of structural complexity in several IL-based systems, including mixtures. The latter represent a change in paradigm in the approach to formulate new, task-specific I…

Ionic Liquids-Cobalt (II) Thermochromic Complexes: How the Structure Tunability Affects "Self-contained" Systems

With the aim of obtaining thermochromic systems with potential applications in solar energy storage, we evaluated the behavior of some sugar-based ionic liquids (ILs)–Co(NTf₂)₂ complexes, in IL solution, as a function of temperature. Different structural changes on the cation, the nature of the anion, and the nature of the IL used as the solvent were considered. The analysis of the above factors was carried out through a combined approach of different techniques, that is, variable temperature UV–vis and NMR spectroscopies, conductivity, and thermal gravimetric analysis. The thermochromic systems were analyzed both as solutions and as thin films, and the data collected highlight the defining…

Sweet Ionic Liquid based Materials for Environmental Applications